Commit | Line | Data |
---|---|---|
e3b3d0f5 | 1 | // SPDX-License-Identifier: GPL-2.0+ |
1da177e4 | 2 | /* |
1da177e4 LT |
3 | * Driver for AMBA serial ports |
4 | * | |
5 | * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o. | |
6 | * | |
7 | * Copyright 1999 ARM Limited | |
8 | * Copyright (C) 2000 Deep Blue Solutions Ltd. | |
68b65f73 | 9 | * Copyright (C) 2010 ST-Ericsson SA |
1da177e4 | 10 | * |
1da177e4 LT |
11 | * This is a generic driver for ARM AMBA-type serial ports. They |
12 | * have a lot of 16550-like features, but are not register compatible. | |
13 | * Note that although they do have CTS, DCD and DSR inputs, they do | |
14 | * not have an RI input, nor do they have DTR or RTS outputs. If | |
15 | * required, these have to be supplied via some other means (eg, GPIO) | |
16 | * and hooked into this driver. | |
17 | */ | |
1da177e4 | 18 | |
1da177e4 LT |
19 | #include <linux/module.h> |
20 | #include <linux/ioport.h> | |
21 | #include <linux/init.h> | |
22 | #include <linux/console.h> | |
23 | #include <linux/sysrq.h> | |
24 | #include <linux/device.h> | |
25 | #include <linux/tty.h> | |
26 | #include <linux/tty_flip.h> | |
27 | #include <linux/serial_core.h> | |
28 | #include <linux/serial.h> | |
a62c80e5 RK |
29 | #include <linux/amba/bus.h> |
30 | #include <linux/amba/serial.h> | |
f8ce2547 | 31 | #include <linux/clk.h> |
5a0e3ad6 | 32 | #include <linux/slab.h> |
68b65f73 RK |
33 | #include <linux/dmaengine.h> |
34 | #include <linux/dma-mapping.h> | |
35 | #include <linux/scatterlist.h> | |
c16d51a3 | 36 | #include <linux/delay.h> |
258aea76 | 37 | #include <linux/types.h> |
32614aad ML |
38 | #include <linux/of.h> |
39 | #include <linux/of_device.h> | |
258e0551 | 40 | #include <linux/pinctrl/consumer.h> |
cb70706c | 41 | #include <linux/sizes.h> |
de609582 | 42 | #include <linux/io.h> |
3db9ab0b | 43 | #include <linux/acpi.h> |
1da177e4 | 44 | |
9f25bc51 RK |
45 | #include "amba-pl011.h" |
46 | ||
1da177e4 LT |
47 | #define UART_NR 14 |
48 | ||
49 | #define SERIAL_AMBA_MAJOR 204 | |
50 | #define SERIAL_AMBA_MINOR 64 | |
51 | #define SERIAL_AMBA_NR UART_NR | |
52 | ||
53 | #define AMBA_ISR_PASS_LIMIT 256 | |
54 | ||
b63d4f0f RK |
55 | #define UART_DR_ERROR (UART011_DR_OE|UART011_DR_BE|UART011_DR_PE|UART011_DR_FE) |
56 | #define UART_DUMMY_DR_RX (1 << 16) | |
1da177e4 | 57 | |
debb7f64 RK |
58 | static u16 pl011_std_offsets[REG_ARRAY_SIZE] = { |
59 | [REG_DR] = UART01x_DR, | |
debb7f64 | 60 | [REG_FR] = UART01x_FR, |
e4df9a80 RK |
61 | [REG_LCRH_RX] = UART011_LCRH, |
62 | [REG_LCRH_TX] = UART011_LCRH, | |
debb7f64 RK |
63 | [REG_IBRD] = UART011_IBRD, |
64 | [REG_FBRD] = UART011_FBRD, | |
debb7f64 RK |
65 | [REG_CR] = UART011_CR, |
66 | [REG_IFLS] = UART011_IFLS, | |
67 | [REG_IMSC] = UART011_IMSC, | |
68 | [REG_RIS] = UART011_RIS, | |
69 | [REG_MIS] = UART011_MIS, | |
70 | [REG_ICR] = UART011_ICR, | |
71 | [REG_DMACR] = UART011_DMACR, | |
debb7f64 RK |
72 | }; |
73 | ||
5926a295 AR |
74 | /* There is by now at least one vendor with differing details, so handle it */ |
75 | struct vendor_data { | |
439403bd | 76 | const u16 *reg_offset; |
5926a295 | 77 | unsigned int ifls; |
0e125a5f SG |
78 | unsigned int fr_busy; |
79 | unsigned int fr_dsr; | |
80 | unsigned int fr_cts; | |
81 | unsigned int fr_ri; | |
d8a4995b | 82 | unsigned int inv_fr; |
84c3e03b | 83 | bool access_32b; |
ac3e3fb4 | 84 | bool oversampling; |
38d62436 | 85 | bool dma_threshold; |
4fd0690b | 86 | bool cts_event_workaround; |
71eec483 | 87 | bool always_enabled; |
cefc2d1d | 88 | bool fixed_options; |
78506f22 | 89 | |
ea33640a | 90 | unsigned int (*get_fifosize)(struct amba_device *dev); |
5926a295 AR |
91 | }; |
92 | ||
ea33640a | 93 | static unsigned int get_fifosize_arm(struct amba_device *dev) |
78506f22 | 94 | { |
ea33640a | 95 | return amba_rev(dev) < 3 ? 16 : 32; |
78506f22 JK |
96 | } |
97 | ||
5926a295 | 98 | static struct vendor_data vendor_arm = { |
439403bd | 99 | .reg_offset = pl011_std_offsets, |
5926a295 | 100 | .ifls = UART011_IFLS_RX4_8|UART011_IFLS_TX4_8, |
0e125a5f SG |
101 | .fr_busy = UART01x_FR_BUSY, |
102 | .fr_dsr = UART01x_FR_DSR, | |
103 | .fr_cts = UART01x_FR_CTS, | |
104 | .fr_ri = UART011_FR_RI, | |
ac3e3fb4 | 105 | .oversampling = false, |
38d62436 | 106 | .dma_threshold = false, |
4fd0690b | 107 | .cts_event_workaround = false, |
71eec483 | 108 | .always_enabled = false, |
cefc2d1d | 109 | .fixed_options = false, |
78506f22 | 110 | .get_fifosize = get_fifosize_arm, |
5926a295 AR |
111 | }; |
112 | ||
d054b3ac | 113 | static const struct vendor_data vendor_sbsa = { |
439403bd | 114 | .reg_offset = pl011_std_offsets, |
0e125a5f SG |
115 | .fr_busy = UART01x_FR_BUSY, |
116 | .fr_dsr = UART01x_FR_DSR, | |
117 | .fr_cts = UART01x_FR_CTS, | |
118 | .fr_ri = UART011_FR_RI, | |
1aabf523 | 119 | .access_32b = true, |
0dd1e247 AP |
120 | .oversampling = false, |
121 | .dma_threshold = false, | |
122 | .cts_event_workaround = false, | |
123 | .always_enabled = true, | |
124 | .fixed_options = true, | |
125 | }; | |
126 | ||
37ef38f3 | 127 | #ifdef CONFIG_ACPI_SPCR_TABLE |
d054b3ac | 128 | static const struct vendor_data vendor_qdt_qdf2400_e44 = { |
d8a4995b CC |
129 | .reg_offset = pl011_std_offsets, |
130 | .fr_busy = UART011_FR_TXFE, | |
131 | .fr_dsr = UART01x_FR_DSR, | |
132 | .fr_cts = UART01x_FR_CTS, | |
133 | .fr_ri = UART011_FR_RI, | |
134 | .inv_fr = UART011_FR_TXFE, | |
135 | .access_32b = true, | |
136 | .oversampling = false, | |
137 | .dma_threshold = false, | |
138 | .cts_event_workaround = false, | |
139 | .always_enabled = true, | |
140 | .fixed_options = true, | |
141 | }; | |
37ef38f3 | 142 | #endif |
d8a4995b | 143 | |
bf69ff8a RK |
144 | static u16 pl011_st_offsets[REG_ARRAY_SIZE] = { |
145 | [REG_DR] = UART01x_DR, | |
146 | [REG_ST_DMAWM] = ST_UART011_DMAWM, | |
147 | [REG_ST_TIMEOUT] = ST_UART011_TIMEOUT, | |
148 | [REG_FR] = UART01x_FR, | |
e4df9a80 RK |
149 | [REG_LCRH_RX] = ST_UART011_LCRH_RX, |
150 | [REG_LCRH_TX] = ST_UART011_LCRH_TX, | |
bf69ff8a RK |
151 | [REG_IBRD] = UART011_IBRD, |
152 | [REG_FBRD] = UART011_FBRD, | |
bf69ff8a RK |
153 | [REG_CR] = UART011_CR, |
154 | [REG_IFLS] = UART011_IFLS, | |
155 | [REG_IMSC] = UART011_IMSC, | |
156 | [REG_RIS] = UART011_RIS, | |
157 | [REG_MIS] = UART011_MIS, | |
158 | [REG_ICR] = UART011_ICR, | |
159 | [REG_DMACR] = UART011_DMACR, | |
160 | [REG_ST_XFCR] = ST_UART011_XFCR, | |
161 | [REG_ST_XON1] = ST_UART011_XON1, | |
162 | [REG_ST_XON2] = ST_UART011_XON2, | |
163 | [REG_ST_XOFF1] = ST_UART011_XOFF1, | |
164 | [REG_ST_XOFF2] = ST_UART011_XOFF2, | |
165 | [REG_ST_ITCR] = ST_UART011_ITCR, | |
166 | [REG_ST_ITIP] = ST_UART011_ITIP, | |
167 | [REG_ST_ABCR] = ST_UART011_ABCR, | |
168 | [REG_ST_ABIMSC] = ST_UART011_ABIMSC, | |
169 | }; | |
170 | ||
ea33640a | 171 | static unsigned int get_fifosize_st(struct amba_device *dev) |
78506f22 JK |
172 | { |
173 | return 64; | |
174 | } | |
175 | ||
5926a295 | 176 | static struct vendor_data vendor_st = { |
bf69ff8a | 177 | .reg_offset = pl011_st_offsets, |
5926a295 | 178 | .ifls = UART011_IFLS_RX_HALF|UART011_IFLS_TX_HALF, |
0e125a5f SG |
179 | .fr_busy = UART01x_FR_BUSY, |
180 | .fr_dsr = UART01x_FR_DSR, | |
181 | .fr_cts = UART01x_FR_CTS, | |
182 | .fr_ri = UART011_FR_RI, | |
ac3e3fb4 | 183 | .oversampling = true, |
38d62436 | 184 | .dma_threshold = true, |
4fd0690b | 185 | .cts_event_workaround = true, |
71eec483 | 186 | .always_enabled = false, |
cefc2d1d | 187 | .fixed_options = false, |
78506f22 | 188 | .get_fifosize = get_fifosize_st, |
1da177e4 LT |
189 | }; |
190 | ||
7ec75871 RK |
191 | static const u16 pl011_zte_offsets[REG_ARRAY_SIZE] = { |
192 | [REG_DR] = ZX_UART011_DR, | |
193 | [REG_FR] = ZX_UART011_FR, | |
194 | [REG_LCRH_RX] = ZX_UART011_LCRH, | |
195 | [REG_LCRH_TX] = ZX_UART011_LCRH, | |
196 | [REG_IBRD] = ZX_UART011_IBRD, | |
197 | [REG_FBRD] = ZX_UART011_FBRD, | |
198 | [REG_CR] = ZX_UART011_CR, | |
199 | [REG_IFLS] = ZX_UART011_IFLS, | |
200 | [REG_IMSC] = ZX_UART011_IMSC, | |
201 | [REG_RIS] = ZX_UART011_RIS, | |
202 | [REG_MIS] = ZX_UART011_MIS, | |
203 | [REG_ICR] = ZX_UART011_ICR, | |
204 | [REG_DMACR] = ZX_UART011_DMACR, | |
205 | }; | |
206 | ||
9c267ddb SG |
207 | static unsigned int get_fifosize_zte(struct amba_device *dev) |
208 | { | |
209 | return 16; | |
210 | } | |
211 | ||
2426fbc7 | 212 | static struct vendor_data vendor_zte = { |
7ec75871 RK |
213 | .reg_offset = pl011_zte_offsets, |
214 | .access_32b = true, | |
215 | .ifls = UART011_IFLS_RX4_8|UART011_IFLS_TX4_8, | |
0e125a5f SG |
216 | .fr_busy = ZX_UART01x_FR_BUSY, |
217 | .fr_dsr = ZX_UART01x_FR_DSR, | |
218 | .fr_cts = ZX_UART01x_FR_CTS, | |
219 | .fr_ri = ZX_UART011_FR_RI, | |
9c267ddb | 220 | .get_fifosize = get_fifosize_zte, |
7ec75871 RK |
221 | }; |
222 | ||
68b65f73 | 223 | /* Deals with DMA transactions */ |
ead76f32 LW |
224 | |
225 | struct pl011_sgbuf { | |
226 | struct scatterlist sg; | |
227 | char *buf; | |
228 | }; | |
229 | ||
230 | struct pl011_dmarx_data { | |
231 | struct dma_chan *chan; | |
232 | struct completion complete; | |
233 | bool use_buf_b; | |
234 | struct pl011_sgbuf sgbuf_a; | |
235 | struct pl011_sgbuf sgbuf_b; | |
236 | dma_cookie_t cookie; | |
237 | bool running; | |
cb06ff10 CM |
238 | struct timer_list timer; |
239 | unsigned int last_residue; | |
240 | unsigned long last_jiffies; | |
241 | bool auto_poll_rate; | |
242 | unsigned int poll_rate; | |
243 | unsigned int poll_timeout; | |
ead76f32 LW |
244 | }; |
245 | ||
68b65f73 RK |
246 | struct pl011_dmatx_data { |
247 | struct dma_chan *chan; | |
248 | struct scatterlist sg; | |
249 | char *buf; | |
250 | bool queued; | |
251 | }; | |
252 | ||
c19f12b5 RK |
253 | /* |
254 | * We wrap our port structure around the generic uart_port. | |
255 | */ | |
256 | struct uart_amba_port { | |
257 | struct uart_port port; | |
debb7f64 | 258 | const u16 *reg_offset; |
c19f12b5 RK |
259 | struct clk *clk; |
260 | const struct vendor_data *vendor; | |
68b65f73 | 261 | unsigned int dmacr; /* dma control reg */ |
c19f12b5 RK |
262 | unsigned int im; /* interrupt mask */ |
263 | unsigned int old_status; | |
ffca2b11 | 264 | unsigned int fifosize; /* vendor-specific */ |
d8d8ffa4 | 265 | unsigned int old_cr; /* state during shutdown */ |
cefc2d1d | 266 | unsigned int fixed_baud; /* vendor-set fixed baud rate */ |
c19f12b5 | 267 | char type[12]; |
68b65f73 RK |
268 | #ifdef CONFIG_DMA_ENGINE |
269 | /* DMA stuff */ | |
ead76f32 LW |
270 | bool using_tx_dma; |
271 | bool using_rx_dma; | |
272 | struct pl011_dmarx_data dmarx; | |
68b65f73 | 273 | struct pl011_dmatx_data dmatx; |
1c9be310 | 274 | bool dma_probed; |
68b65f73 RK |
275 | #endif |
276 | }; | |
277 | ||
9f25bc51 RK |
278 | static unsigned int pl011_reg_to_offset(const struct uart_amba_port *uap, |
279 | unsigned int reg) | |
280 | { | |
debb7f64 | 281 | return uap->reg_offset[reg]; |
9f25bc51 RK |
282 | } |
283 | ||
b2a4e24c RK |
284 | static unsigned int pl011_read(const struct uart_amba_port *uap, |
285 | unsigned int reg) | |
75836339 | 286 | { |
84c3e03b RK |
287 | void __iomem *addr = uap->port.membase + pl011_reg_to_offset(uap, reg); |
288 | ||
3b78fae7 TT |
289 | return (uap->port.iotype == UPIO_MEM32) ? |
290 | readl_relaxed(addr) : readw_relaxed(addr); | |
75836339 RK |
291 | } |
292 | ||
b2a4e24c RK |
293 | static void pl011_write(unsigned int val, const struct uart_amba_port *uap, |
294 | unsigned int reg) | |
75836339 | 295 | { |
84c3e03b RK |
296 | void __iomem *addr = uap->port.membase + pl011_reg_to_offset(uap, reg); |
297 | ||
3b78fae7 | 298 | if (uap->port.iotype == UPIO_MEM32) |
f5ce6edd | 299 | writel_relaxed(val, addr); |
84c3e03b | 300 | else |
f5ce6edd | 301 | writew_relaxed(val, addr); |
75836339 RK |
302 | } |
303 | ||
29772c4e LW |
304 | /* |
305 | * Reads up to 256 characters from the FIFO or until it's empty and | |
306 | * inserts them into the TTY layer. Returns the number of characters | |
307 | * read from the FIFO. | |
308 | */ | |
309 | static int pl011_fifo_to_tty(struct uart_amba_port *uap) | |
310 | { | |
e73be92d | 311 | unsigned int ch, flag, fifotaken; |
534cf755 PZ |
312 | int sysrq; |
313 | u16 status; | |
29772c4e | 314 | |
e73be92d | 315 | for (fifotaken = 0; fifotaken != 256; fifotaken++) { |
9f25bc51 | 316 | status = pl011_read(uap, REG_FR); |
29772c4e LW |
317 | if (status & UART01x_FR_RXFE) |
318 | break; | |
319 | ||
320 | /* Take chars from the FIFO and update status */ | |
9f25bc51 | 321 | ch = pl011_read(uap, REG_DR) | UART_DUMMY_DR_RX; |
29772c4e LW |
322 | flag = TTY_NORMAL; |
323 | uap->port.icount.rx++; | |
29772c4e LW |
324 | |
325 | if (unlikely(ch & UART_DR_ERROR)) { | |
326 | if (ch & UART011_DR_BE) { | |
327 | ch &= ~(UART011_DR_FE | UART011_DR_PE); | |
328 | uap->port.icount.brk++; | |
329 | if (uart_handle_break(&uap->port)) | |
330 | continue; | |
331 | } else if (ch & UART011_DR_PE) | |
332 | uap->port.icount.parity++; | |
333 | else if (ch & UART011_DR_FE) | |
334 | uap->port.icount.frame++; | |
335 | if (ch & UART011_DR_OE) | |
336 | uap->port.icount.overrun++; | |
337 | ||
338 | ch &= uap->port.read_status_mask; | |
339 | ||
340 | if (ch & UART011_DR_BE) | |
341 | flag = TTY_BREAK; | |
342 | else if (ch & UART011_DR_PE) | |
343 | flag = TTY_PARITY; | |
344 | else if (ch & UART011_DR_FE) | |
345 | flag = TTY_FRAME; | |
346 | } | |
347 | ||
534cf755 PZ |
348 | spin_unlock(&uap->port.lock); |
349 | sysrq = uart_handle_sysrq_char(&uap->port, ch & 255); | |
350 | spin_lock(&uap->port.lock); | |
29772c4e | 351 | |
534cf755 PZ |
352 | if (!sysrq) |
353 | uart_insert_char(&uap->port, ch, UART011_DR_OE, ch, flag); | |
29772c4e LW |
354 | } |
355 | ||
356 | return fifotaken; | |
357 | } | |
358 | ||
359 | ||
68b65f73 RK |
360 | /* |
361 | * All the DMA operation mode stuff goes inside this ifdef. | |
362 | * This assumes that you have a generic DMA device interface, | |
363 | * no custom DMA interfaces are supported. | |
364 | */ | |
365 | #ifdef CONFIG_DMA_ENGINE | |
366 | ||
367 | #define PL011_DMA_BUFFER_SIZE PAGE_SIZE | |
368 | ||
ead76f32 LW |
369 | static int pl011_sgbuf_init(struct dma_chan *chan, struct pl011_sgbuf *sg, |
370 | enum dma_data_direction dir) | |
371 | { | |
cb06ff10 CM |
372 | dma_addr_t dma_addr; |
373 | ||
374 | sg->buf = dma_alloc_coherent(chan->device->dev, | |
375 | PL011_DMA_BUFFER_SIZE, &dma_addr, GFP_KERNEL); | |
ead76f32 LW |
376 | if (!sg->buf) |
377 | return -ENOMEM; | |
378 | ||
cb06ff10 CM |
379 | sg_init_table(&sg->sg, 1); |
380 | sg_set_page(&sg->sg, phys_to_page(dma_addr), | |
381 | PL011_DMA_BUFFER_SIZE, offset_in_page(dma_addr)); | |
382 | sg_dma_address(&sg->sg) = dma_addr; | |
c64be923 | 383 | sg_dma_len(&sg->sg) = PL011_DMA_BUFFER_SIZE; |
ead76f32 | 384 | |
ead76f32 LW |
385 | return 0; |
386 | } | |
387 | ||
388 | static void pl011_sgbuf_free(struct dma_chan *chan, struct pl011_sgbuf *sg, | |
389 | enum dma_data_direction dir) | |
390 | { | |
391 | if (sg->buf) { | |
cb06ff10 CM |
392 | dma_free_coherent(chan->device->dev, |
393 | PL011_DMA_BUFFER_SIZE, sg->buf, | |
394 | sg_dma_address(&sg->sg)); | |
ead76f32 LW |
395 | } |
396 | } | |
397 | ||
1c9be310 | 398 | static void pl011_dma_probe(struct uart_amba_port *uap) |
68b65f73 RK |
399 | { |
400 | /* DMA is the sole user of the platform data right now */ | |
574de559 | 401 | struct amba_pl011_data *plat = dev_get_platdata(uap->port.dev); |
1c9be310 | 402 | struct device *dev = uap->port.dev; |
68b65f73 | 403 | struct dma_slave_config tx_conf = { |
9f25bc51 RK |
404 | .dst_addr = uap->port.mapbase + |
405 | pl011_reg_to_offset(uap, REG_DR), | |
68b65f73 | 406 | .dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE, |
a485df4b | 407 | .direction = DMA_MEM_TO_DEV, |
68b65f73 | 408 | .dst_maxburst = uap->fifosize >> 1, |
258aea76 | 409 | .device_fc = false, |
68b65f73 RK |
410 | }; |
411 | struct dma_chan *chan; | |
412 | dma_cap_mask_t mask; | |
413 | ||
1c9be310 | 414 | uap->dma_probed = true; |
61b37b04 | 415 | chan = dma_request_chan(dev, "tx"); |
1c9be310 JRO |
416 | if (IS_ERR(chan)) { |
417 | if (PTR_ERR(chan) == -EPROBE_DEFER) { | |
1c9be310 JRO |
418 | uap->dma_probed = false; |
419 | return; | |
420 | } | |
68b65f73 | 421 | |
787b0c1f AB |
422 | /* We need platform data */ |
423 | if (!plat || !plat->dma_filter) { | |
424 | dev_info(uap->port.dev, "no DMA platform data\n"); | |
425 | return; | |
426 | } | |
427 | ||
428 | /* Try to acquire a generic DMA engine slave TX channel */ | |
429 | dma_cap_zero(mask); | |
430 | dma_cap_set(DMA_SLAVE, mask); | |
431 | ||
432 | chan = dma_request_channel(mask, plat->dma_filter, | |
433 | plat->dma_tx_param); | |
434 | if (!chan) { | |
435 | dev_err(uap->port.dev, "no TX DMA channel!\n"); | |
436 | return; | |
437 | } | |
68b65f73 RK |
438 | } |
439 | ||
440 | dmaengine_slave_config(chan, &tx_conf); | |
441 | uap->dmatx.chan = chan; | |
442 | ||
443 | dev_info(uap->port.dev, "DMA channel TX %s\n", | |
444 | dma_chan_name(uap->dmatx.chan)); | |
ead76f32 LW |
445 | |
446 | /* Optionally make use of an RX channel as well */ | |
787b0c1f | 447 | chan = dma_request_slave_channel(dev, "rx"); |
0d3c673e | 448 | |
d9e105ca | 449 | if (!chan && plat && plat->dma_rx_param) { |
787b0c1f AB |
450 | chan = dma_request_channel(mask, plat->dma_filter, plat->dma_rx_param); |
451 | ||
452 | if (!chan) { | |
453 | dev_err(uap->port.dev, "no RX DMA channel!\n"); | |
454 | return; | |
455 | } | |
456 | } | |
457 | ||
458 | if (chan) { | |
ead76f32 | 459 | struct dma_slave_config rx_conf = { |
9f25bc51 RK |
460 | .src_addr = uap->port.mapbase + |
461 | pl011_reg_to_offset(uap, REG_DR), | |
ead76f32 | 462 | .src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE, |
a485df4b | 463 | .direction = DMA_DEV_TO_MEM, |
b2aeb775 | 464 | .src_maxburst = uap->fifosize >> 2, |
258aea76 | 465 | .device_fc = false, |
ead76f32 | 466 | }; |
2d3b7d6e AJ |
467 | struct dma_slave_caps caps; |
468 | ||
469 | /* | |
470 | * Some DMA controllers provide information on their capabilities. | |
471 | * If the controller does, check for suitable residue processing | |
472 | * otherwise assime all is well. | |
473 | */ | |
474 | if (0 == dma_get_slave_caps(chan, &caps)) { | |
475 | if (caps.residue_granularity == | |
476 | DMA_RESIDUE_GRANULARITY_DESCRIPTOR) { | |
477 | dma_release_channel(chan); | |
478 | dev_info(uap->port.dev, | |
479 | "RX DMA disabled - no residue processing\n"); | |
480 | return; | |
481 | } | |
482 | } | |
ead76f32 LW |
483 | dmaengine_slave_config(chan, &rx_conf); |
484 | uap->dmarx.chan = chan; | |
485 | ||
98267d33 | 486 | uap->dmarx.auto_poll_rate = false; |
8f898bfd | 487 | if (plat && plat->dma_rx_poll_enable) { |
cb06ff10 CM |
488 | /* Set poll rate if specified. */ |
489 | if (plat->dma_rx_poll_rate) { | |
490 | uap->dmarx.auto_poll_rate = false; | |
491 | uap->dmarx.poll_rate = plat->dma_rx_poll_rate; | |
492 | } else { | |
493 | /* | |
494 | * 100 ms defaults to poll rate if not | |
495 | * specified. This will be adjusted with | |
496 | * the baud rate at set_termios. | |
497 | */ | |
498 | uap->dmarx.auto_poll_rate = true; | |
499 | uap->dmarx.poll_rate = 100; | |
500 | } | |
501 | /* 3 secs defaults poll_timeout if not specified. */ | |
502 | if (plat->dma_rx_poll_timeout) | |
503 | uap->dmarx.poll_timeout = | |
504 | plat->dma_rx_poll_timeout; | |
505 | else | |
506 | uap->dmarx.poll_timeout = 3000; | |
98267d33 AJ |
507 | } else if (!plat && dev->of_node) { |
508 | uap->dmarx.auto_poll_rate = of_property_read_bool( | |
509 | dev->of_node, "auto-poll"); | |
510 | if (uap->dmarx.auto_poll_rate) { | |
511 | u32 x; | |
512 | ||
513 | if (0 == of_property_read_u32(dev->of_node, | |
514 | "poll-rate-ms", &x)) | |
515 | uap->dmarx.poll_rate = x; | |
516 | else | |
517 | uap->dmarx.poll_rate = 100; | |
518 | if (0 == of_property_read_u32(dev->of_node, | |
519 | "poll-timeout-ms", &x)) | |
520 | uap->dmarx.poll_timeout = x; | |
521 | else | |
522 | uap->dmarx.poll_timeout = 3000; | |
523 | } | |
524 | } | |
ead76f32 LW |
525 | dev_info(uap->port.dev, "DMA channel RX %s\n", |
526 | dma_chan_name(uap->dmarx.chan)); | |
527 | } | |
68b65f73 RK |
528 | } |
529 | ||
68b65f73 RK |
530 | static void pl011_dma_remove(struct uart_amba_port *uap) |
531 | { | |
68b65f73 RK |
532 | if (uap->dmatx.chan) |
533 | dma_release_channel(uap->dmatx.chan); | |
ead76f32 LW |
534 | if (uap->dmarx.chan) |
535 | dma_release_channel(uap->dmarx.chan); | |
68b65f73 RK |
536 | } |
537 | ||
734745ca | 538 | /* Forward declare these for the refill routine */ |
68b65f73 | 539 | static int pl011_dma_tx_refill(struct uart_amba_port *uap); |
734745ca | 540 | static void pl011_start_tx_pio(struct uart_amba_port *uap); |
68b65f73 RK |
541 | |
542 | /* | |
543 | * The current DMA TX buffer has been sent. | |
544 | * Try to queue up another DMA buffer. | |
545 | */ | |
546 | static void pl011_dma_tx_callback(void *data) | |
547 | { | |
548 | struct uart_amba_port *uap = data; | |
549 | struct pl011_dmatx_data *dmatx = &uap->dmatx; | |
550 | unsigned long flags; | |
551 | u16 dmacr; | |
552 | ||
553 | spin_lock_irqsave(&uap->port.lock, flags); | |
554 | if (uap->dmatx.queued) | |
555 | dma_unmap_sg(dmatx->chan->device->dev, &dmatx->sg, 1, | |
556 | DMA_TO_DEVICE); | |
557 | ||
558 | dmacr = uap->dmacr; | |
559 | uap->dmacr = dmacr & ~UART011_TXDMAE; | |
9f25bc51 | 560 | pl011_write(uap->dmacr, uap, REG_DMACR); |
68b65f73 RK |
561 | |
562 | /* | |
563 | * If TX DMA was disabled, it means that we've stopped the DMA for | |
564 | * some reason (eg, XOFF received, or we want to send an X-char.) | |
565 | * | |
566 | * Note: we need to be careful here of a potential race between DMA | |
567 | * and the rest of the driver - if the driver disables TX DMA while | |
568 | * a TX buffer completing, we must update the tx queued status to | |
569 | * get further refills (hence we check dmacr). | |
570 | */ | |
571 | if (!(dmacr & UART011_TXDMAE) || uart_tx_stopped(&uap->port) || | |
572 | uart_circ_empty(&uap->port.state->xmit)) { | |
573 | uap->dmatx.queued = false; | |
574 | spin_unlock_irqrestore(&uap->port.lock, flags); | |
575 | return; | |
576 | } | |
577 | ||
734745ca | 578 | if (pl011_dma_tx_refill(uap) <= 0) |
68b65f73 RK |
579 | /* |
580 | * We didn't queue a DMA buffer for some reason, but we | |
581 | * have data pending to be sent. Re-enable the TX IRQ. | |
582 | */ | |
734745ca DM |
583 | pl011_start_tx_pio(uap); |
584 | ||
68b65f73 RK |
585 | spin_unlock_irqrestore(&uap->port.lock, flags); |
586 | } | |
587 | ||
588 | /* | |
589 | * Try to refill the TX DMA buffer. | |
590 | * Locking: called with port lock held and IRQs disabled. | |
591 | * Returns: | |
592 | * 1 if we queued up a TX DMA buffer. | |
593 | * 0 if we didn't want to handle this by DMA | |
594 | * <0 on error | |
595 | */ | |
596 | static int pl011_dma_tx_refill(struct uart_amba_port *uap) | |
597 | { | |
598 | struct pl011_dmatx_data *dmatx = &uap->dmatx; | |
599 | struct dma_chan *chan = dmatx->chan; | |
600 | struct dma_device *dma_dev = chan->device; | |
601 | struct dma_async_tx_descriptor *desc; | |
602 | struct circ_buf *xmit = &uap->port.state->xmit; | |
603 | unsigned int count; | |
604 | ||
605 | /* | |
606 | * Try to avoid the overhead involved in using DMA if the | |
607 | * transaction fits in the first half of the FIFO, by using | |
608 | * the standard interrupt handling. This ensures that we | |
609 | * issue a uart_write_wakeup() at the appropriate time. | |
610 | */ | |
611 | count = uart_circ_chars_pending(xmit); | |
612 | if (count < (uap->fifosize >> 1)) { | |
613 | uap->dmatx.queued = false; | |
614 | return 0; | |
615 | } | |
616 | ||
617 | /* | |
618 | * Bodge: don't send the last character by DMA, as this | |
619 | * will prevent XON from notifying us to restart DMA. | |
620 | */ | |
621 | count -= 1; | |
622 | ||
623 | /* Else proceed to copy the TX chars to the DMA buffer and fire DMA */ | |
624 | if (count > PL011_DMA_BUFFER_SIZE) | |
625 | count = PL011_DMA_BUFFER_SIZE; | |
626 | ||
627 | if (xmit->tail < xmit->head) | |
628 | memcpy(&dmatx->buf[0], &xmit->buf[xmit->tail], count); | |
629 | else { | |
630 | size_t first = UART_XMIT_SIZE - xmit->tail; | |
e2a545a6 AJ |
631 | size_t second; |
632 | ||
633 | if (first > count) | |
634 | first = count; | |
635 | second = count - first; | |
68b65f73 RK |
636 | |
637 | memcpy(&dmatx->buf[0], &xmit->buf[xmit->tail], first); | |
638 | if (second) | |
639 | memcpy(&dmatx->buf[first], &xmit->buf[0], second); | |
640 | } | |
641 | ||
642 | dmatx->sg.length = count; | |
643 | ||
644 | if (dma_map_sg(dma_dev->dev, &dmatx->sg, 1, DMA_TO_DEVICE) != 1) { | |
645 | uap->dmatx.queued = false; | |
646 | dev_dbg(uap->port.dev, "unable to map TX DMA\n"); | |
647 | return -EBUSY; | |
648 | } | |
649 | ||
16052827 | 650 | desc = dmaengine_prep_slave_sg(chan, &dmatx->sg, 1, DMA_MEM_TO_DEV, |
68b65f73 RK |
651 | DMA_PREP_INTERRUPT | DMA_CTRL_ACK); |
652 | if (!desc) { | |
653 | dma_unmap_sg(dma_dev->dev, &dmatx->sg, 1, DMA_TO_DEVICE); | |
654 | uap->dmatx.queued = false; | |
655 | /* | |
656 | * If DMA cannot be used right now, we complete this | |
657 | * transaction via IRQ and let the TTY layer retry. | |
658 | */ | |
659 | dev_dbg(uap->port.dev, "TX DMA busy\n"); | |
660 | return -EBUSY; | |
661 | } | |
662 | ||
663 | /* Some data to go along to the callback */ | |
664 | desc->callback = pl011_dma_tx_callback; | |
665 | desc->callback_param = uap; | |
666 | ||
667 | /* All errors should happen at prepare time */ | |
668 | dmaengine_submit(desc); | |
669 | ||
670 | /* Fire the DMA transaction */ | |
671 | dma_dev->device_issue_pending(chan); | |
672 | ||
673 | uap->dmacr |= UART011_TXDMAE; | |
9f25bc51 | 674 | pl011_write(uap->dmacr, uap, REG_DMACR); |
68b65f73 RK |
675 | uap->dmatx.queued = true; |
676 | ||
677 | /* | |
678 | * Now we know that DMA will fire, so advance the ring buffer | |
679 | * with the stuff we just dispatched. | |
680 | */ | |
681 | xmit->tail = (xmit->tail + count) & (UART_XMIT_SIZE - 1); | |
682 | uap->port.icount.tx += count; | |
683 | ||
684 | if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) | |
685 | uart_write_wakeup(&uap->port); | |
686 | ||
687 | return 1; | |
688 | } | |
689 | ||
690 | /* | |
691 | * We received a transmit interrupt without a pending X-char but with | |
692 | * pending characters. | |
693 | * Locking: called with port lock held and IRQs disabled. | |
694 | * Returns: | |
695 | * false if we want to use PIO to transmit | |
696 | * true if we queued a DMA buffer | |
697 | */ | |
698 | static bool pl011_dma_tx_irq(struct uart_amba_port *uap) | |
699 | { | |
ead76f32 | 700 | if (!uap->using_tx_dma) |
68b65f73 RK |
701 | return false; |
702 | ||
703 | /* | |
704 | * If we already have a TX buffer queued, but received a | |
705 | * TX interrupt, it will be because we've just sent an X-char. | |
706 | * Ensure the TX DMA is enabled and the TX IRQ is disabled. | |
707 | */ | |
708 | if (uap->dmatx.queued) { | |
709 | uap->dmacr |= UART011_TXDMAE; | |
9f25bc51 | 710 | pl011_write(uap->dmacr, uap, REG_DMACR); |
68b65f73 | 711 | uap->im &= ~UART011_TXIM; |
9f25bc51 | 712 | pl011_write(uap->im, uap, REG_IMSC); |
68b65f73 RK |
713 | return true; |
714 | } | |
715 | ||
716 | /* | |
717 | * We don't have a TX buffer queued, so try to queue one. | |
25985edc | 718 | * If we successfully queued a buffer, mask the TX IRQ. |
68b65f73 RK |
719 | */ |
720 | if (pl011_dma_tx_refill(uap) > 0) { | |
721 | uap->im &= ~UART011_TXIM; | |
9f25bc51 | 722 | pl011_write(uap->im, uap, REG_IMSC); |
68b65f73 RK |
723 | return true; |
724 | } | |
725 | return false; | |
726 | } | |
727 | ||
728 | /* | |
729 | * Stop the DMA transmit (eg, due to received XOFF). | |
730 | * Locking: called with port lock held and IRQs disabled. | |
731 | */ | |
732 | static inline void pl011_dma_tx_stop(struct uart_amba_port *uap) | |
733 | { | |
734 | if (uap->dmatx.queued) { | |
735 | uap->dmacr &= ~UART011_TXDMAE; | |
9f25bc51 | 736 | pl011_write(uap->dmacr, uap, REG_DMACR); |
68b65f73 RK |
737 | } |
738 | } | |
739 | ||
740 | /* | |
741 | * Try to start a DMA transmit, or in the case of an XON/OFF | |
742 | * character queued for send, try to get that character out ASAP. | |
743 | * Locking: called with port lock held and IRQs disabled. | |
744 | * Returns: | |
745 | * false if we want the TX IRQ to be enabled | |
746 | * true if we have a buffer queued | |
747 | */ | |
748 | static inline bool pl011_dma_tx_start(struct uart_amba_port *uap) | |
749 | { | |
750 | u16 dmacr; | |
751 | ||
ead76f32 | 752 | if (!uap->using_tx_dma) |
68b65f73 RK |
753 | return false; |
754 | ||
755 | if (!uap->port.x_char) { | |
756 | /* no X-char, try to push chars out in DMA mode */ | |
757 | bool ret = true; | |
758 | ||
759 | if (!uap->dmatx.queued) { | |
760 | if (pl011_dma_tx_refill(uap) > 0) { | |
761 | uap->im &= ~UART011_TXIM; | |
9f25bc51 | 762 | pl011_write(uap->im, uap, REG_IMSC); |
734745ca | 763 | } else |
68b65f73 | 764 | ret = false; |
68b65f73 RK |
765 | } else if (!(uap->dmacr & UART011_TXDMAE)) { |
766 | uap->dmacr |= UART011_TXDMAE; | |
9f25bc51 | 767 | pl011_write(uap->dmacr, uap, REG_DMACR); |
68b65f73 RK |
768 | } |
769 | return ret; | |
770 | } | |
771 | ||
772 | /* | |
773 | * We have an X-char to send. Disable DMA to prevent it loading | |
774 | * the TX fifo, and then see if we can stuff it into the FIFO. | |
775 | */ | |
776 | dmacr = uap->dmacr; | |
777 | uap->dmacr &= ~UART011_TXDMAE; | |
9f25bc51 | 778 | pl011_write(uap->dmacr, uap, REG_DMACR); |
68b65f73 | 779 | |
9f25bc51 | 780 | if (pl011_read(uap, REG_FR) & UART01x_FR_TXFF) { |
68b65f73 RK |
781 | /* |
782 | * No space in the FIFO, so enable the transmit interrupt | |
783 | * so we know when there is space. Note that once we've | |
784 | * loaded the character, we should just re-enable DMA. | |
785 | */ | |
786 | return false; | |
787 | } | |
788 | ||
9f25bc51 | 789 | pl011_write(uap->port.x_char, uap, REG_DR); |
68b65f73 RK |
790 | uap->port.icount.tx++; |
791 | uap->port.x_char = 0; | |
792 | ||
793 | /* Success - restore the DMA state */ | |
794 | uap->dmacr = dmacr; | |
9f25bc51 | 795 | pl011_write(dmacr, uap, REG_DMACR); |
68b65f73 RK |
796 | |
797 | return true; | |
798 | } | |
799 | ||
800 | /* | |
801 | * Flush the transmit buffer. | |
802 | * Locking: called with port lock held and IRQs disabled. | |
803 | */ | |
804 | static void pl011_dma_flush_buffer(struct uart_port *port) | |
b83286bf FE |
805 | __releases(&uap->port.lock) |
806 | __acquires(&uap->port.lock) | |
68b65f73 | 807 | { |
a5820c24 DT |
808 | struct uart_amba_port *uap = |
809 | container_of(port, struct uart_amba_port, port); | |
68b65f73 | 810 | |
ead76f32 | 811 | if (!uap->using_tx_dma) |
68b65f73 RK |
812 | return; |
813 | ||
f6a19647 VW |
814 | dmaengine_terminate_async(uap->dmatx.chan); |
815 | ||
68b65f73 RK |
816 | if (uap->dmatx.queued) { |
817 | dma_unmap_sg(uap->dmatx.chan->device->dev, &uap->dmatx.sg, 1, | |
818 | DMA_TO_DEVICE); | |
819 | uap->dmatx.queued = false; | |
820 | uap->dmacr &= ~UART011_TXDMAE; | |
9f25bc51 | 821 | pl011_write(uap->dmacr, uap, REG_DMACR); |
68b65f73 RK |
822 | } |
823 | } | |
824 | ||
ead76f32 LW |
825 | static void pl011_dma_rx_callback(void *data); |
826 | ||
827 | static int pl011_dma_rx_trigger_dma(struct uart_amba_port *uap) | |
828 | { | |
829 | struct dma_chan *rxchan = uap->dmarx.chan; | |
ead76f32 LW |
830 | struct pl011_dmarx_data *dmarx = &uap->dmarx; |
831 | struct dma_async_tx_descriptor *desc; | |
832 | struct pl011_sgbuf *sgbuf; | |
833 | ||
834 | if (!rxchan) | |
835 | return -EIO; | |
836 | ||
837 | /* Start the RX DMA job */ | |
838 | sgbuf = uap->dmarx.use_buf_b ? | |
839 | &uap->dmarx.sgbuf_b : &uap->dmarx.sgbuf_a; | |
16052827 | 840 | desc = dmaengine_prep_slave_sg(rxchan, &sgbuf->sg, 1, |
a485df4b | 841 | DMA_DEV_TO_MEM, |
ead76f32 LW |
842 | DMA_PREP_INTERRUPT | DMA_CTRL_ACK); |
843 | /* | |
844 | * If the DMA engine is busy and cannot prepare a | |
845 | * channel, no big deal, the driver will fall back | |
846 | * to interrupt mode as a result of this error code. | |
847 | */ | |
848 | if (!desc) { | |
849 | uap->dmarx.running = false; | |
850 | dmaengine_terminate_all(rxchan); | |
851 | return -EBUSY; | |
852 | } | |
853 | ||
854 | /* Some data to go along to the callback */ | |
855 | desc->callback = pl011_dma_rx_callback; | |
856 | desc->callback_param = uap; | |
857 | dmarx->cookie = dmaengine_submit(desc); | |
858 | dma_async_issue_pending(rxchan); | |
859 | ||
860 | uap->dmacr |= UART011_RXDMAE; | |
9f25bc51 | 861 | pl011_write(uap->dmacr, uap, REG_DMACR); |
ead76f32 LW |
862 | uap->dmarx.running = true; |
863 | ||
864 | uap->im &= ~UART011_RXIM; | |
9f25bc51 | 865 | pl011_write(uap->im, uap, REG_IMSC); |
ead76f32 LW |
866 | |
867 | return 0; | |
868 | } | |
869 | ||
870 | /* | |
871 | * This is called when either the DMA job is complete, or | |
872 | * the FIFO timeout interrupt occurred. This must be called | |
873 | * with the port spinlock uap->port.lock held. | |
874 | */ | |
875 | static void pl011_dma_rx_chars(struct uart_amba_port *uap, | |
876 | u32 pending, bool use_buf_b, | |
877 | bool readfifo) | |
878 | { | |
05c7cd39 | 879 | struct tty_port *port = &uap->port.state->port; |
ead76f32 LW |
880 | struct pl011_sgbuf *sgbuf = use_buf_b ? |
881 | &uap->dmarx.sgbuf_b : &uap->dmarx.sgbuf_a; | |
ead76f32 LW |
882 | int dma_count = 0; |
883 | u32 fifotaken = 0; /* only used for vdbg() */ | |
884 | ||
cb06ff10 CM |
885 | struct pl011_dmarx_data *dmarx = &uap->dmarx; |
886 | int dmataken = 0; | |
887 | ||
888 | if (uap->dmarx.poll_rate) { | |
889 | /* The data can be taken by polling */ | |
890 | dmataken = sgbuf->sg.length - dmarx->last_residue; | |
891 | /* Recalculate the pending size */ | |
892 | if (pending >= dmataken) | |
893 | pending -= dmataken; | |
894 | } | |
895 | ||
896 | /* Pick the remain data from the DMA */ | |
ead76f32 | 897 | if (pending) { |
ead76f32 LW |
898 | |
899 | /* | |
900 | * First take all chars in the DMA pipe, then look in the FIFO. | |
901 | * Note that tty_insert_flip_buf() tries to take as many chars | |
902 | * as it can. | |
903 | */ | |
cb06ff10 CM |
904 | dma_count = tty_insert_flip_string(port, sgbuf->buf + dmataken, |
905 | pending); | |
ead76f32 LW |
906 | |
907 | uap->port.icount.rx += dma_count; | |
908 | if (dma_count < pending) | |
909 | dev_warn(uap->port.dev, | |
910 | "couldn't insert all characters (TTY is full?)\n"); | |
911 | } | |
912 | ||
cb06ff10 CM |
913 | /* Reset the last_residue for Rx DMA poll */ |
914 | if (uap->dmarx.poll_rate) | |
915 | dmarx->last_residue = sgbuf->sg.length; | |
916 | ||
ead76f32 LW |
917 | /* |
918 | * Only continue with trying to read the FIFO if all DMA chars have | |
919 | * been taken first. | |
920 | */ | |
921 | if (dma_count == pending && readfifo) { | |
922 | /* Clear any error flags */ | |
75836339 | 923 | pl011_write(UART011_OEIS | UART011_BEIS | UART011_PEIS | |
9f25bc51 | 924 | UART011_FEIS, uap, REG_ICR); |
ead76f32 LW |
925 | |
926 | /* | |
927 | * If we read all the DMA'd characters, and we had an | |
29772c4e LW |
928 | * incomplete buffer, that could be due to an rx error, or |
929 | * maybe we just timed out. Read any pending chars and check | |
930 | * the error status. | |
931 | * | |
932 | * Error conditions will only occur in the FIFO, these will | |
933 | * trigger an immediate interrupt and stop the DMA job, so we | |
934 | * will always find the error in the FIFO, never in the DMA | |
935 | * buffer. | |
ead76f32 | 936 | */ |
29772c4e | 937 | fifotaken = pl011_fifo_to_tty(uap); |
ead76f32 LW |
938 | } |
939 | ||
ead76f32 LW |
940 | dev_vdbg(uap->port.dev, |
941 | "Took %d chars from DMA buffer and %d chars from the FIFO\n", | |
942 | dma_count, fifotaken); | |
2e124b4a | 943 | tty_flip_buffer_push(port); |
ead76f32 LW |
944 | } |
945 | ||
946 | static void pl011_dma_rx_irq(struct uart_amba_port *uap) | |
947 | { | |
948 | struct pl011_dmarx_data *dmarx = &uap->dmarx; | |
949 | struct dma_chan *rxchan = dmarx->chan; | |
950 | struct pl011_sgbuf *sgbuf = dmarx->use_buf_b ? | |
951 | &dmarx->sgbuf_b : &dmarx->sgbuf_a; | |
952 | size_t pending; | |
953 | struct dma_tx_state state; | |
954 | enum dma_status dmastat; | |
955 | ||
956 | /* | |
957 | * Pause the transfer so we can trust the current counter, | |
958 | * do this before we pause the PL011 block, else we may | |
959 | * overflow the FIFO. | |
960 | */ | |
961 | if (dmaengine_pause(rxchan)) | |
962 | dev_err(uap->port.dev, "unable to pause DMA transfer\n"); | |
963 | dmastat = rxchan->device->device_tx_status(rxchan, | |
964 | dmarx->cookie, &state); | |
965 | if (dmastat != DMA_PAUSED) | |
966 | dev_err(uap->port.dev, "unable to pause DMA transfer\n"); | |
967 | ||
968 | /* Disable RX DMA - incoming data will wait in the FIFO */ | |
969 | uap->dmacr &= ~UART011_RXDMAE; | |
9f25bc51 | 970 | pl011_write(uap->dmacr, uap, REG_DMACR); |
ead76f32 LW |
971 | uap->dmarx.running = false; |
972 | ||
973 | pending = sgbuf->sg.length - state.residue; | |
974 | BUG_ON(pending > PL011_DMA_BUFFER_SIZE); | |
975 | /* Then we terminate the transfer - we now know our residue */ | |
976 | dmaengine_terminate_all(rxchan); | |
977 | ||
978 | /* | |
979 | * This will take the chars we have so far and insert | |
980 | * into the framework. | |
981 | */ | |
982 | pl011_dma_rx_chars(uap, pending, dmarx->use_buf_b, true); | |
983 | ||
984 | /* Switch buffer & re-trigger DMA job */ | |
985 | dmarx->use_buf_b = !dmarx->use_buf_b; | |
986 | if (pl011_dma_rx_trigger_dma(uap)) { | |
987 | dev_dbg(uap->port.dev, "could not retrigger RX DMA job " | |
988 | "fall back to interrupt mode\n"); | |
989 | uap->im |= UART011_RXIM; | |
9f25bc51 | 990 | pl011_write(uap->im, uap, REG_IMSC); |
ead76f32 LW |
991 | } |
992 | } | |
993 | ||
994 | static void pl011_dma_rx_callback(void *data) | |
995 | { | |
996 | struct uart_amba_port *uap = data; | |
997 | struct pl011_dmarx_data *dmarx = &uap->dmarx; | |
6dc01aa6 | 998 | struct dma_chan *rxchan = dmarx->chan; |
ead76f32 | 999 | bool lastbuf = dmarx->use_buf_b; |
6dc01aa6 CM |
1000 | struct pl011_sgbuf *sgbuf = dmarx->use_buf_b ? |
1001 | &dmarx->sgbuf_b : &dmarx->sgbuf_a; | |
1002 | size_t pending; | |
1003 | struct dma_tx_state state; | |
ead76f32 LW |
1004 | int ret; |
1005 | ||
1006 | /* | |
1007 | * This completion interrupt occurs typically when the | |
1008 | * RX buffer is totally stuffed but no timeout has yet | |
1009 | * occurred. When that happens, we just want the RX | |
1010 | * routine to flush out the secondary DMA buffer while | |
1011 | * we immediately trigger the next DMA job. | |
1012 | */ | |
1013 | spin_lock_irq(&uap->port.lock); | |
6dc01aa6 CM |
1014 | /* |
1015 | * Rx data can be taken by the UART interrupts during | |
1016 | * the DMA irq handler. So we check the residue here. | |
1017 | */ | |
1018 | rxchan->device->device_tx_status(rxchan, dmarx->cookie, &state); | |
1019 | pending = sgbuf->sg.length - state.residue; | |
1020 | BUG_ON(pending > PL011_DMA_BUFFER_SIZE); | |
1021 | /* Then we terminate the transfer - we now know our residue */ | |
1022 | dmaengine_terminate_all(rxchan); | |
1023 | ||
ead76f32 LW |
1024 | uap->dmarx.running = false; |
1025 | dmarx->use_buf_b = !lastbuf; | |
1026 | ret = pl011_dma_rx_trigger_dma(uap); | |
1027 | ||
6dc01aa6 | 1028 | pl011_dma_rx_chars(uap, pending, lastbuf, false); |
ead76f32 LW |
1029 | spin_unlock_irq(&uap->port.lock); |
1030 | /* | |
1031 | * Do this check after we picked the DMA chars so we don't | |
1032 | * get some IRQ immediately from RX. | |
1033 | */ | |
1034 | if (ret) { | |
1035 | dev_dbg(uap->port.dev, "could not retrigger RX DMA job " | |
1036 | "fall back to interrupt mode\n"); | |
1037 | uap->im |= UART011_RXIM; | |
9f25bc51 | 1038 | pl011_write(uap->im, uap, REG_IMSC); |
ead76f32 LW |
1039 | } |
1040 | } | |
1041 | ||
1042 | /* | |
1043 | * Stop accepting received characters, when we're shutting down or | |
1044 | * suspending this port. | |
1045 | * Locking: called with port lock held and IRQs disabled. | |
1046 | */ | |
1047 | static inline void pl011_dma_rx_stop(struct uart_amba_port *uap) | |
1048 | { | |
1049 | /* FIXME. Just disable the DMA enable */ | |
1050 | uap->dmacr &= ~UART011_RXDMAE; | |
9f25bc51 | 1051 | pl011_write(uap->dmacr, uap, REG_DMACR); |
ead76f32 | 1052 | } |
68b65f73 | 1053 | |
cb06ff10 CM |
1054 | /* |
1055 | * Timer handler for Rx DMA polling. | |
1056 | * Every polling, It checks the residue in the dma buffer and transfer | |
1057 | * data to the tty. Also, last_residue is updated for the next polling. | |
1058 | */ | |
f7f73096 | 1059 | static void pl011_dma_rx_poll(struct timer_list *t) |
cb06ff10 | 1060 | { |
f7f73096 | 1061 | struct uart_amba_port *uap = from_timer(uap, t, dmarx.timer); |
cb06ff10 CM |
1062 | struct tty_port *port = &uap->port.state->port; |
1063 | struct pl011_dmarx_data *dmarx = &uap->dmarx; | |
1064 | struct dma_chan *rxchan = uap->dmarx.chan; | |
1065 | unsigned long flags = 0; | |
1066 | unsigned int dmataken = 0; | |
1067 | unsigned int size = 0; | |
1068 | struct pl011_sgbuf *sgbuf; | |
1069 | int dma_count; | |
1070 | struct dma_tx_state state; | |
1071 | ||
1072 | sgbuf = dmarx->use_buf_b ? &uap->dmarx.sgbuf_b : &uap->dmarx.sgbuf_a; | |
1073 | rxchan->device->device_tx_status(rxchan, dmarx->cookie, &state); | |
1074 | if (likely(state.residue < dmarx->last_residue)) { | |
1075 | dmataken = sgbuf->sg.length - dmarx->last_residue; | |
1076 | size = dmarx->last_residue - state.residue; | |
1077 | dma_count = tty_insert_flip_string(port, sgbuf->buf + dmataken, | |
1078 | size); | |
1079 | if (dma_count == size) | |
1080 | dmarx->last_residue = state.residue; | |
1081 | dmarx->last_jiffies = jiffies; | |
1082 | } | |
1083 | tty_flip_buffer_push(port); | |
1084 | ||
1085 | /* | |
1086 | * If no data is received in poll_timeout, the driver will fall back | |
1087 | * to interrupt mode. We will retrigger DMA at the first interrupt. | |
1088 | */ | |
1089 | if (jiffies_to_msecs(jiffies - dmarx->last_jiffies) | |
1090 | > uap->dmarx.poll_timeout) { | |
1091 | ||
1092 | spin_lock_irqsave(&uap->port.lock, flags); | |
1093 | pl011_dma_rx_stop(uap); | |
c25a1ad7 | 1094 | uap->im |= UART011_RXIM; |
9f25bc51 | 1095 | pl011_write(uap->im, uap, REG_IMSC); |
cb06ff10 CM |
1096 | spin_unlock_irqrestore(&uap->port.lock, flags); |
1097 | ||
1098 | uap->dmarx.running = false; | |
1099 | dmaengine_terminate_all(rxchan); | |
1100 | del_timer(&uap->dmarx.timer); | |
1101 | } else { | |
1102 | mod_timer(&uap->dmarx.timer, | |
1103 | jiffies + msecs_to_jiffies(uap->dmarx.poll_rate)); | |
1104 | } | |
1105 | } | |
1106 | ||
68b65f73 RK |
1107 | static void pl011_dma_startup(struct uart_amba_port *uap) |
1108 | { | |
ead76f32 LW |
1109 | int ret; |
1110 | ||
1c9be310 JRO |
1111 | if (!uap->dma_probed) |
1112 | pl011_dma_probe(uap); | |
1113 | ||
68b65f73 RK |
1114 | if (!uap->dmatx.chan) |
1115 | return; | |
1116 | ||
4c0be45b | 1117 | uap->dmatx.buf = kmalloc(PL011_DMA_BUFFER_SIZE, GFP_KERNEL | __GFP_DMA); |
68b65f73 RK |
1118 | if (!uap->dmatx.buf) { |
1119 | dev_err(uap->port.dev, "no memory for DMA TX buffer\n"); | |
1120 | uap->port.fifosize = uap->fifosize; | |
1121 | return; | |
1122 | } | |
1123 | ||
1124 | sg_init_one(&uap->dmatx.sg, uap->dmatx.buf, PL011_DMA_BUFFER_SIZE); | |
1125 | ||
1126 | /* The DMA buffer is now the FIFO the TTY subsystem can use */ | |
1127 | uap->port.fifosize = PL011_DMA_BUFFER_SIZE; | |
ead76f32 LW |
1128 | uap->using_tx_dma = true; |
1129 | ||
1130 | if (!uap->dmarx.chan) | |
1131 | goto skip_rx; | |
1132 | ||
1133 | /* Allocate and map DMA RX buffers */ | |
1134 | ret = pl011_sgbuf_init(uap->dmarx.chan, &uap->dmarx.sgbuf_a, | |
1135 | DMA_FROM_DEVICE); | |
1136 | if (ret) { | |
1137 | dev_err(uap->port.dev, "failed to init DMA %s: %d\n", | |
1138 | "RX buffer A", ret); | |
1139 | goto skip_rx; | |
1140 | } | |
68b65f73 | 1141 | |
ead76f32 LW |
1142 | ret = pl011_sgbuf_init(uap->dmarx.chan, &uap->dmarx.sgbuf_b, |
1143 | DMA_FROM_DEVICE); | |
1144 | if (ret) { | |
1145 | dev_err(uap->port.dev, "failed to init DMA %s: %d\n", | |
1146 | "RX buffer B", ret); | |
1147 | pl011_sgbuf_free(uap->dmarx.chan, &uap->dmarx.sgbuf_a, | |
1148 | DMA_FROM_DEVICE); | |
1149 | goto skip_rx; | |
1150 | } | |
1151 | ||
1152 | uap->using_rx_dma = true; | |
68b65f73 | 1153 | |
ead76f32 | 1154 | skip_rx: |
68b65f73 RK |
1155 | /* Turn on DMA error (RX/TX will be enabled on demand) */ |
1156 | uap->dmacr |= UART011_DMAONERR; | |
9f25bc51 | 1157 | pl011_write(uap->dmacr, uap, REG_DMACR); |
38d62436 RK |
1158 | |
1159 | /* | |
1160 | * ST Micro variants has some specific dma burst threshold | |
1161 | * compensation. Set this to 16 bytes, so burst will only | |
1162 | * be issued above/below 16 bytes. | |
1163 | */ | |
1164 | if (uap->vendor->dma_threshold) | |
75836339 | 1165 | pl011_write(ST_UART011_DMAWM_RX_16 | ST_UART011_DMAWM_TX_16, |
9f25bc51 | 1166 | uap, REG_ST_DMAWM); |
ead76f32 LW |
1167 | |
1168 | if (uap->using_rx_dma) { | |
1169 | if (pl011_dma_rx_trigger_dma(uap)) | |
1170 | dev_dbg(uap->port.dev, "could not trigger initial " | |
1171 | "RX DMA job, fall back to interrupt mode\n"); | |
cb06ff10 | 1172 | if (uap->dmarx.poll_rate) { |
f7f73096 | 1173 | timer_setup(&uap->dmarx.timer, pl011_dma_rx_poll, 0); |
cb06ff10 CM |
1174 | mod_timer(&uap->dmarx.timer, |
1175 | jiffies + | |
1176 | msecs_to_jiffies(uap->dmarx.poll_rate)); | |
1177 | uap->dmarx.last_residue = PL011_DMA_BUFFER_SIZE; | |
1178 | uap->dmarx.last_jiffies = jiffies; | |
1179 | } | |
ead76f32 | 1180 | } |
68b65f73 RK |
1181 | } |
1182 | ||
1183 | static void pl011_dma_shutdown(struct uart_amba_port *uap) | |
1184 | { | |
ead76f32 | 1185 | if (!(uap->using_tx_dma || uap->using_rx_dma)) |
68b65f73 RK |
1186 | return; |
1187 | ||
1188 | /* Disable RX and TX DMA */ | |
0e125a5f | 1189 | while (pl011_read(uap, REG_FR) & uap->vendor->fr_busy) |
2f2fd089 | 1190 | cpu_relax(); |
68b65f73 RK |
1191 | |
1192 | spin_lock_irq(&uap->port.lock); | |
1193 | uap->dmacr &= ~(UART011_DMAONERR | UART011_RXDMAE | UART011_TXDMAE); | |
9f25bc51 | 1194 | pl011_write(uap->dmacr, uap, REG_DMACR); |
68b65f73 RK |
1195 | spin_unlock_irq(&uap->port.lock); |
1196 | ||
ead76f32 LW |
1197 | if (uap->using_tx_dma) { |
1198 | /* In theory, this should already be done by pl011_dma_flush_buffer */ | |
1199 | dmaengine_terminate_all(uap->dmatx.chan); | |
1200 | if (uap->dmatx.queued) { | |
1201 | dma_unmap_sg(uap->dmatx.chan->device->dev, &uap->dmatx.sg, 1, | |
1202 | DMA_TO_DEVICE); | |
1203 | uap->dmatx.queued = false; | |
1204 | } | |
1205 | ||
1206 | kfree(uap->dmatx.buf); | |
1207 | uap->using_tx_dma = false; | |
68b65f73 RK |
1208 | } |
1209 | ||
ead76f32 LW |
1210 | if (uap->using_rx_dma) { |
1211 | dmaengine_terminate_all(uap->dmarx.chan); | |
1212 | /* Clean up the RX DMA */ | |
1213 | pl011_sgbuf_free(uap->dmarx.chan, &uap->dmarx.sgbuf_a, DMA_FROM_DEVICE); | |
1214 | pl011_sgbuf_free(uap->dmarx.chan, &uap->dmarx.sgbuf_b, DMA_FROM_DEVICE); | |
cb06ff10 CM |
1215 | if (uap->dmarx.poll_rate) |
1216 | del_timer_sync(&uap->dmarx.timer); | |
ead76f32 LW |
1217 | uap->using_rx_dma = false; |
1218 | } | |
1219 | } | |
68b65f73 | 1220 | |
ead76f32 LW |
1221 | static inline bool pl011_dma_rx_available(struct uart_amba_port *uap) |
1222 | { | |
1223 | return uap->using_rx_dma; | |
68b65f73 RK |
1224 | } |
1225 | ||
ead76f32 LW |
1226 | static inline bool pl011_dma_rx_running(struct uart_amba_port *uap) |
1227 | { | |
1228 | return uap->using_rx_dma && uap->dmarx.running; | |
1229 | } | |
1230 | ||
68b65f73 RK |
1231 | #else |
1232 | /* Blank functions if the DMA engine is not available */ | |
68b65f73 RK |
1233 | static inline void pl011_dma_remove(struct uart_amba_port *uap) |
1234 | { | |
1235 | } | |
1236 | ||
1237 | static inline void pl011_dma_startup(struct uart_amba_port *uap) | |
1238 | { | |
1239 | } | |
1240 | ||
1241 | static inline void pl011_dma_shutdown(struct uart_amba_port *uap) | |
1242 | { | |
1243 | } | |
1244 | ||
1245 | static inline bool pl011_dma_tx_irq(struct uart_amba_port *uap) | |
1246 | { | |
1247 | return false; | |
1248 | } | |
1249 | ||
1250 | static inline void pl011_dma_tx_stop(struct uart_amba_port *uap) | |
1251 | { | |
1252 | } | |
1253 | ||
1254 | static inline bool pl011_dma_tx_start(struct uart_amba_port *uap) | |
1255 | { | |
1256 | return false; | |
1257 | } | |
1258 | ||
ead76f32 LW |
1259 | static inline void pl011_dma_rx_irq(struct uart_amba_port *uap) |
1260 | { | |
1261 | } | |
1262 | ||
1263 | static inline void pl011_dma_rx_stop(struct uart_amba_port *uap) | |
1264 | { | |
1265 | } | |
1266 | ||
1267 | static inline int pl011_dma_rx_trigger_dma(struct uart_amba_port *uap) | |
1268 | { | |
1269 | return -EIO; | |
1270 | } | |
1271 | ||
1272 | static inline bool pl011_dma_rx_available(struct uart_amba_port *uap) | |
1273 | { | |
1274 | return false; | |
1275 | } | |
1276 | ||
1277 | static inline bool pl011_dma_rx_running(struct uart_amba_port *uap) | |
1278 | { | |
1279 | return false; | |
1280 | } | |
1281 | ||
68b65f73 RK |
1282 | #define pl011_dma_flush_buffer NULL |
1283 | #endif | |
1284 | ||
b129a8cc | 1285 | static void pl011_stop_tx(struct uart_port *port) |
1da177e4 | 1286 | { |
a5820c24 DT |
1287 | struct uart_amba_port *uap = |
1288 | container_of(port, struct uart_amba_port, port); | |
1da177e4 LT |
1289 | |
1290 | uap->im &= ~UART011_TXIM; | |
9f25bc51 | 1291 | pl011_write(uap->im, uap, REG_IMSC); |
68b65f73 | 1292 | pl011_dma_tx_stop(uap); |
1da177e4 LT |
1293 | } |
1294 | ||
7d05587c | 1295 | static bool pl011_tx_chars(struct uart_amba_port *uap, bool from_irq); |
734745ca DM |
1296 | |
1297 | /* Start TX with programmed I/O only (no DMA) */ | |
1298 | static void pl011_start_tx_pio(struct uart_amba_port *uap) | |
1299 | { | |
7d05587c J |
1300 | if (pl011_tx_chars(uap, false)) { |
1301 | uap->im |= UART011_TXIM; | |
1302 | pl011_write(uap->im, uap, REG_IMSC); | |
1303 | } | |
734745ca DM |
1304 | } |
1305 | ||
b129a8cc | 1306 | static void pl011_start_tx(struct uart_port *port) |
1da177e4 | 1307 | { |
a5820c24 DT |
1308 | struct uart_amba_port *uap = |
1309 | container_of(port, struct uart_amba_port, port); | |
1da177e4 | 1310 | |
734745ca DM |
1311 | if (!pl011_dma_tx_start(uap)) |
1312 | pl011_start_tx_pio(uap); | |
1da177e4 LT |
1313 | } |
1314 | ||
1315 | static void pl011_stop_rx(struct uart_port *port) | |
1316 | { | |
a5820c24 DT |
1317 | struct uart_amba_port *uap = |
1318 | container_of(port, struct uart_amba_port, port); | |
1da177e4 LT |
1319 | |
1320 | uap->im &= ~(UART011_RXIM|UART011_RTIM|UART011_FEIM| | |
1321 | UART011_PEIM|UART011_BEIM|UART011_OEIM); | |
9f25bc51 | 1322 | pl011_write(uap->im, uap, REG_IMSC); |
ead76f32 LW |
1323 | |
1324 | pl011_dma_rx_stop(uap); | |
1da177e4 LT |
1325 | } |
1326 | ||
1327 | static void pl011_enable_ms(struct uart_port *port) | |
1328 | { | |
a5820c24 DT |
1329 | struct uart_amba_port *uap = |
1330 | container_of(port, struct uart_amba_port, port); | |
1da177e4 LT |
1331 | |
1332 | uap->im |= UART011_RIMIM|UART011_CTSMIM|UART011_DCDMIM|UART011_DSRMIM; | |
9f25bc51 | 1333 | pl011_write(uap->im, uap, REG_IMSC); |
1da177e4 LT |
1334 | } |
1335 | ||
7d12e780 | 1336 | static void pl011_rx_chars(struct uart_amba_port *uap) |
b83286bf FE |
1337 | __releases(&uap->port.lock) |
1338 | __acquires(&uap->port.lock) | |
1da177e4 | 1339 | { |
29772c4e | 1340 | pl011_fifo_to_tty(uap); |
1da177e4 | 1341 | |
2389b272 | 1342 | spin_unlock(&uap->port.lock); |
2e124b4a | 1343 | tty_flip_buffer_push(&uap->port.state->port); |
ead76f32 LW |
1344 | /* |
1345 | * If we were temporarily out of DMA mode for a while, | |
1346 | * attempt to switch back to DMA mode again. | |
1347 | */ | |
1348 | if (pl011_dma_rx_available(uap)) { | |
1349 | if (pl011_dma_rx_trigger_dma(uap)) { | |
1350 | dev_dbg(uap->port.dev, "could not trigger RX DMA job " | |
1351 | "fall back to interrupt mode again\n"); | |
1352 | uap->im |= UART011_RXIM; | |
9f25bc51 | 1353 | pl011_write(uap->im, uap, REG_IMSC); |
cb06ff10 | 1354 | } else { |
89fa28db | 1355 | #ifdef CONFIG_DMA_ENGINE |
cb06ff10 CM |
1356 | /* Start Rx DMA poll */ |
1357 | if (uap->dmarx.poll_rate) { | |
1358 | uap->dmarx.last_jiffies = jiffies; | |
1359 | uap->dmarx.last_residue = PL011_DMA_BUFFER_SIZE; | |
1360 | mod_timer(&uap->dmarx.timer, | |
1361 | jiffies + | |
1362 | msecs_to_jiffies(uap->dmarx.poll_rate)); | |
1363 | } | |
89fa28db | 1364 | #endif |
cb06ff10 | 1365 | } |
ead76f32 | 1366 | } |
2389b272 | 1367 | spin_lock(&uap->port.lock); |
1da177e4 LT |
1368 | } |
1369 | ||
1e84d223 DM |
1370 | static bool pl011_tx_char(struct uart_amba_port *uap, unsigned char c, |
1371 | bool from_irq) | |
734745ca | 1372 | { |
1e84d223 | 1373 | if (unlikely(!from_irq) && |
9f25bc51 | 1374 | pl011_read(uap, REG_FR) & UART01x_FR_TXFF) |
1e84d223 DM |
1375 | return false; /* unable to transmit character */ |
1376 | ||
9f25bc51 | 1377 | pl011_write(c, uap, REG_DR); |
734745ca DM |
1378 | uap->port.icount.tx++; |
1379 | ||
1e84d223 | 1380 | return true; |
734745ca DM |
1381 | } |
1382 | ||
7d05587c J |
1383 | /* Returns true if tx interrupts have to be (kept) enabled */ |
1384 | static bool pl011_tx_chars(struct uart_amba_port *uap, bool from_irq) | |
1da177e4 | 1385 | { |
ebd2c8f6 | 1386 | struct circ_buf *xmit = &uap->port.state->xmit; |
1e84d223 | 1387 | int count = uap->fifosize >> 1; |
734745ca | 1388 | |
1da177e4 | 1389 | if (uap->port.x_char) { |
1e84d223 | 1390 | if (!pl011_tx_char(uap, uap->port.x_char, from_irq)) |
7d05587c | 1391 | return true; |
1da177e4 | 1392 | uap->port.x_char = 0; |
734745ca | 1393 | --count; |
1da177e4 LT |
1394 | } |
1395 | if (uart_circ_empty(xmit) || uart_tx_stopped(&uap->port)) { | |
b129a8cc | 1396 | pl011_stop_tx(&uap->port); |
7d05587c | 1397 | return false; |
1da177e4 LT |
1398 | } |
1399 | ||
68b65f73 RK |
1400 | /* If we are using DMA mode, try to send some characters. */ |
1401 | if (pl011_dma_tx_irq(uap)) | |
7d05587c | 1402 | return true; |
68b65f73 | 1403 | |
1e84d223 DM |
1404 | do { |
1405 | if (likely(from_irq) && count-- == 0) | |
1da177e4 | 1406 | break; |
1e84d223 DM |
1407 | |
1408 | if (!pl011_tx_char(uap, xmit->buf[xmit->tail], from_irq)) | |
1409 | break; | |
1410 | ||
1411 | xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); | |
1412 | } while (!uart_circ_empty(xmit)); | |
1da177e4 LT |
1413 | |
1414 | if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) | |
1415 | uart_write_wakeup(&uap->port); | |
1416 | ||
7d05587c | 1417 | if (uart_circ_empty(xmit)) { |
b129a8cc | 1418 | pl011_stop_tx(&uap->port); |
7d05587c J |
1419 | return false; |
1420 | } | |
1421 | return true; | |
1da177e4 LT |
1422 | } |
1423 | ||
1424 | static void pl011_modem_status(struct uart_amba_port *uap) | |
1425 | { | |
1426 | unsigned int status, delta; | |
1427 | ||
9f25bc51 | 1428 | status = pl011_read(uap, REG_FR) & UART01x_FR_MODEM_ANY; |
1da177e4 LT |
1429 | |
1430 | delta = status ^ uap->old_status; | |
1431 | uap->old_status = status; | |
1432 | ||
1433 | if (!delta) | |
1434 | return; | |
1435 | ||
1436 | if (delta & UART01x_FR_DCD) | |
1437 | uart_handle_dcd_change(&uap->port, status & UART01x_FR_DCD); | |
1438 | ||
0e125a5f | 1439 | if (delta & uap->vendor->fr_dsr) |
1da177e4 LT |
1440 | uap->port.icount.dsr++; |
1441 | ||
0e125a5f SG |
1442 | if (delta & uap->vendor->fr_cts) |
1443 | uart_handle_cts_change(&uap->port, | |
1444 | status & uap->vendor->fr_cts); | |
1da177e4 | 1445 | |
bdc04e31 | 1446 | wake_up_interruptible(&uap->port.state->port.delta_msr_wait); |
1da177e4 LT |
1447 | } |
1448 | ||
9c4ef4b0 AP |
1449 | static void check_apply_cts_event_workaround(struct uart_amba_port *uap) |
1450 | { | |
9c4ef4b0 AP |
1451 | if (!uap->vendor->cts_event_workaround) |
1452 | return; | |
1453 | ||
1454 | /* workaround to make sure that all bits are unlocked.. */ | |
9f25bc51 | 1455 | pl011_write(0x00, uap, REG_ICR); |
9c4ef4b0 AP |
1456 | |
1457 | /* | |
1458 | * WA: introduce 26ns(1 uart clk) delay before W1C; | |
1459 | * single apb access will incur 2 pclk(133.12Mhz) delay, | |
1460 | * so add 2 dummy reads | |
1461 | */ | |
94345aee XW |
1462 | pl011_read(uap, REG_ICR); |
1463 | pl011_read(uap, REG_ICR); | |
9c4ef4b0 AP |
1464 | } |
1465 | ||
7d12e780 | 1466 | static irqreturn_t pl011_int(int irq, void *dev_id) |
1da177e4 LT |
1467 | { |
1468 | struct uart_amba_port *uap = dev_id; | |
963cc981 | 1469 | unsigned long flags; |
1da177e4 LT |
1470 | unsigned int status, pass_counter = AMBA_ISR_PASS_LIMIT; |
1471 | int handled = 0; | |
1472 | ||
963cc981 | 1473 | spin_lock_irqsave(&uap->port.lock, flags); |
d3a96c94 | 1474 | status = pl011_read(uap, REG_RIS) & uap->im; |
1da177e4 LT |
1475 | if (status) { |
1476 | do { | |
9c4ef4b0 | 1477 | check_apply_cts_event_workaround(uap); |
f11c9841 | 1478 | |
75836339 RK |
1479 | pl011_write(status & ~(UART011_TXIS|UART011_RTIS| |
1480 | UART011_RXIS), | |
9f25bc51 | 1481 | uap, REG_ICR); |
1da177e4 | 1482 | |
ead76f32 LW |
1483 | if (status & (UART011_RTIS|UART011_RXIS)) { |
1484 | if (pl011_dma_rx_running(uap)) | |
1485 | pl011_dma_rx_irq(uap); | |
1486 | else | |
1487 | pl011_rx_chars(uap); | |
1488 | } | |
1da177e4 LT |
1489 | if (status & (UART011_DSRMIS|UART011_DCDMIS| |
1490 | UART011_CTSMIS|UART011_RIMIS)) | |
1491 | pl011_modem_status(uap); | |
1e84d223 DM |
1492 | if (status & UART011_TXIS) |
1493 | pl011_tx_chars(uap, true); | |
1da177e4 | 1494 | |
4fd0690b | 1495 | if (pass_counter-- == 0) |
1da177e4 LT |
1496 | break; |
1497 | ||
d3a96c94 | 1498 | status = pl011_read(uap, REG_RIS) & uap->im; |
1da177e4 LT |
1499 | } while (status != 0); |
1500 | handled = 1; | |
1501 | } | |
1502 | ||
963cc981 | 1503 | spin_unlock_irqrestore(&uap->port.lock, flags); |
1da177e4 LT |
1504 | |
1505 | return IRQ_RETVAL(handled); | |
1506 | } | |
1507 | ||
e643f87f | 1508 | static unsigned int pl011_tx_empty(struct uart_port *port) |
1da177e4 | 1509 | { |
a5820c24 DT |
1510 | struct uart_amba_port *uap = |
1511 | container_of(port, struct uart_amba_port, port); | |
d8a4995b CC |
1512 | |
1513 | /* Allow feature register bits to be inverted to work around errata */ | |
1514 | unsigned int status = pl011_read(uap, REG_FR) ^ uap->vendor->inv_fr; | |
1515 | ||
0e125a5f SG |
1516 | return status & (uap->vendor->fr_busy | UART01x_FR_TXFF) ? |
1517 | 0 : TIOCSER_TEMT; | |
1da177e4 LT |
1518 | } |
1519 | ||
e643f87f | 1520 | static unsigned int pl011_get_mctrl(struct uart_port *port) |
1da177e4 | 1521 | { |
a5820c24 DT |
1522 | struct uart_amba_port *uap = |
1523 | container_of(port, struct uart_amba_port, port); | |
1da177e4 | 1524 | unsigned int result = 0; |
9f25bc51 | 1525 | unsigned int status = pl011_read(uap, REG_FR); |
1da177e4 | 1526 | |
5159f407 | 1527 | #define TIOCMBIT(uartbit, tiocmbit) \ |
1da177e4 LT |
1528 | if (status & uartbit) \ |
1529 | result |= tiocmbit | |
1530 | ||
5159f407 | 1531 | TIOCMBIT(UART01x_FR_DCD, TIOCM_CAR); |
0e125a5f SG |
1532 | TIOCMBIT(uap->vendor->fr_dsr, TIOCM_DSR); |
1533 | TIOCMBIT(uap->vendor->fr_cts, TIOCM_CTS); | |
1534 | TIOCMBIT(uap->vendor->fr_ri, TIOCM_RNG); | |
5159f407 | 1535 | #undef TIOCMBIT |
1da177e4 LT |
1536 | return result; |
1537 | } | |
1538 | ||
1539 | static void pl011_set_mctrl(struct uart_port *port, unsigned int mctrl) | |
1540 | { | |
a5820c24 DT |
1541 | struct uart_amba_port *uap = |
1542 | container_of(port, struct uart_amba_port, port); | |
1da177e4 LT |
1543 | unsigned int cr; |
1544 | ||
9f25bc51 | 1545 | cr = pl011_read(uap, REG_CR); |
1da177e4 | 1546 | |
5159f407 | 1547 | #define TIOCMBIT(tiocmbit, uartbit) \ |
1da177e4 LT |
1548 | if (mctrl & tiocmbit) \ |
1549 | cr |= uartbit; \ | |
1550 | else \ | |
1551 | cr &= ~uartbit | |
1552 | ||
5159f407 JS |
1553 | TIOCMBIT(TIOCM_RTS, UART011_CR_RTS); |
1554 | TIOCMBIT(TIOCM_DTR, UART011_CR_DTR); | |
1555 | TIOCMBIT(TIOCM_OUT1, UART011_CR_OUT1); | |
1556 | TIOCMBIT(TIOCM_OUT2, UART011_CR_OUT2); | |
1557 | TIOCMBIT(TIOCM_LOOP, UART011_CR_LBE); | |
3b43816f | 1558 | |
2a76fa28 | 1559 | if (port->status & UPSTAT_AUTORTS) { |
3b43816f RV |
1560 | /* We need to disable auto-RTS if we want to turn RTS off */ |
1561 | TIOCMBIT(TIOCM_RTS, UART011_CR_RTSEN); | |
1562 | } | |
5159f407 | 1563 | #undef TIOCMBIT |
1da177e4 | 1564 | |
9f25bc51 | 1565 | pl011_write(cr, uap, REG_CR); |
1da177e4 LT |
1566 | } |
1567 | ||
1568 | static void pl011_break_ctl(struct uart_port *port, int break_state) | |
1569 | { | |
a5820c24 DT |
1570 | struct uart_amba_port *uap = |
1571 | container_of(port, struct uart_amba_port, port); | |
1da177e4 LT |
1572 | unsigned long flags; |
1573 | unsigned int lcr_h; | |
1574 | ||
1575 | spin_lock_irqsave(&uap->port.lock, flags); | |
e4df9a80 | 1576 | lcr_h = pl011_read(uap, REG_LCRH_TX); |
1da177e4 LT |
1577 | if (break_state == -1) |
1578 | lcr_h |= UART01x_LCRH_BRK; | |
1579 | else | |
1580 | lcr_h &= ~UART01x_LCRH_BRK; | |
e4df9a80 | 1581 | pl011_write(lcr_h, uap, REG_LCRH_TX); |
1da177e4 LT |
1582 | spin_unlock_irqrestore(&uap->port.lock, flags); |
1583 | } | |
1584 | ||
84b5ae15 | 1585 | #ifdef CONFIG_CONSOLE_POLL |
5c8124a0 AV |
1586 | |
1587 | static void pl011_quiesce_irqs(struct uart_port *port) | |
1588 | { | |
a5820c24 DT |
1589 | struct uart_amba_port *uap = |
1590 | container_of(port, struct uart_amba_port, port); | |
5c8124a0 | 1591 | |
9f25bc51 | 1592 | pl011_write(pl011_read(uap, REG_MIS), uap, REG_ICR); |
5c8124a0 AV |
1593 | /* |
1594 | * There is no way to clear TXIM as this is "ready to transmit IRQ", so | |
1595 | * we simply mask it. start_tx() will unmask it. | |
1596 | * | |
1597 | * Note we can race with start_tx(), and if the race happens, the | |
1598 | * polling user might get another interrupt just after we clear it. | |
1599 | * But it should be OK and can happen even w/o the race, e.g. | |
1600 | * controller immediately got some new data and raised the IRQ. | |
1601 | * | |
1602 | * And whoever uses polling routines assumes that it manages the device | |
1603 | * (including tx queue), so we're also fine with start_tx()'s caller | |
1604 | * side. | |
1605 | */ | |
9f25bc51 RK |
1606 | pl011_write(pl011_read(uap, REG_IMSC) & ~UART011_TXIM, uap, |
1607 | REG_IMSC); | |
5c8124a0 AV |
1608 | } |
1609 | ||
e643f87f | 1610 | static int pl011_get_poll_char(struct uart_port *port) |
84b5ae15 | 1611 | { |
a5820c24 DT |
1612 | struct uart_amba_port *uap = |
1613 | container_of(port, struct uart_amba_port, port); | |
84b5ae15 JW |
1614 | unsigned int status; |
1615 | ||
5c8124a0 AV |
1616 | /* |
1617 | * The caller might need IRQs lowered, e.g. if used with KDB NMI | |
1618 | * debugger. | |
1619 | */ | |
1620 | pl011_quiesce_irqs(port); | |
1621 | ||
9f25bc51 | 1622 | status = pl011_read(uap, REG_FR); |
f5316b4a JW |
1623 | if (status & UART01x_FR_RXFE) |
1624 | return NO_POLL_CHAR; | |
84b5ae15 | 1625 | |
9f25bc51 | 1626 | return pl011_read(uap, REG_DR); |
84b5ae15 JW |
1627 | } |
1628 | ||
e643f87f | 1629 | static void pl011_put_poll_char(struct uart_port *port, |
84b5ae15 JW |
1630 | unsigned char ch) |
1631 | { | |
a5820c24 DT |
1632 | struct uart_amba_port *uap = |
1633 | container_of(port, struct uart_amba_port, port); | |
84b5ae15 | 1634 | |
9f25bc51 | 1635 | while (pl011_read(uap, REG_FR) & UART01x_FR_TXFF) |
2f2fd089 | 1636 | cpu_relax(); |
84b5ae15 | 1637 | |
9f25bc51 | 1638 | pl011_write(ch, uap, REG_DR); |
84b5ae15 JW |
1639 | } |
1640 | ||
1641 | #endif /* CONFIG_CONSOLE_POLL */ | |
1642 | ||
b3564c2c | 1643 | static int pl011_hwinit(struct uart_port *port) |
1da177e4 | 1644 | { |
a5820c24 DT |
1645 | struct uart_amba_port *uap = |
1646 | container_of(port, struct uart_amba_port, port); | |
1da177e4 LT |
1647 | int retval; |
1648 | ||
78d80c5a | 1649 | /* Optionaly enable pins to be muxed in and configured */ |
2b996fc5 | 1650 | pinctrl_pm_select_default_state(port->dev); |
78d80c5a | 1651 | |
1da177e4 LT |
1652 | /* |
1653 | * Try to enable the clock producer. | |
1654 | */ | |
1c4c4394 | 1655 | retval = clk_prepare_enable(uap->clk); |
1da177e4 | 1656 | if (retval) |
7f6d942a | 1657 | return retval; |
1da177e4 LT |
1658 | |
1659 | uap->port.uartclk = clk_get_rate(uap->clk); | |
1660 | ||
9b96fbac | 1661 | /* Clear pending error and receive interrupts */ |
75836339 RK |
1662 | pl011_write(UART011_OEIS | UART011_BEIS | UART011_PEIS | |
1663 | UART011_FEIS | UART011_RTIS | UART011_RXIS, | |
9f25bc51 | 1664 | uap, REG_ICR); |
9b96fbac | 1665 | |
b3564c2c AV |
1666 | /* |
1667 | * Save interrupts enable mask, and enable RX interrupts in case if | |
1668 | * the interrupt is used for NMI entry. | |
1669 | */ | |
9f25bc51 RK |
1670 | uap->im = pl011_read(uap, REG_IMSC); |
1671 | pl011_write(UART011_RTIM | UART011_RXIM, uap, REG_IMSC); | |
b3564c2c | 1672 | |
574de559 | 1673 | if (dev_get_platdata(uap->port.dev)) { |
b3564c2c AV |
1674 | struct amba_pl011_data *plat; |
1675 | ||
574de559 | 1676 | plat = dev_get_platdata(uap->port.dev); |
b3564c2c AV |
1677 | if (plat->init) |
1678 | plat->init(); | |
1679 | } | |
1680 | return 0; | |
b3564c2c AV |
1681 | } |
1682 | ||
7fe9a5a9 RK |
1683 | static bool pl011_split_lcrh(const struct uart_amba_port *uap) |
1684 | { | |
e4df9a80 RK |
1685 | return pl011_reg_to_offset(uap, REG_LCRH_RX) != |
1686 | pl011_reg_to_offset(uap, REG_LCRH_TX); | |
7fe9a5a9 RK |
1687 | } |
1688 | ||
b60f2f66 JM |
1689 | static void pl011_write_lcr_h(struct uart_amba_port *uap, unsigned int lcr_h) |
1690 | { | |
e4df9a80 | 1691 | pl011_write(lcr_h, uap, REG_LCRH_RX); |
7fe9a5a9 | 1692 | if (pl011_split_lcrh(uap)) { |
b60f2f66 JM |
1693 | int i; |
1694 | /* | |
1695 | * Wait 10 PCLKs before writing LCRH_TX register, | |
1696 | * to get this delay write read only register 10 times | |
1697 | */ | |
1698 | for (i = 0; i < 10; ++i) | |
9f25bc51 | 1699 | pl011_write(0xff, uap, REG_MIS); |
e4df9a80 | 1700 | pl011_write(lcr_h, uap, REG_LCRH_TX); |
b60f2f66 JM |
1701 | } |
1702 | } | |
1703 | ||
867b8e8e AP |
1704 | static int pl011_allocate_irq(struct uart_amba_port *uap) |
1705 | { | |
9f25bc51 | 1706 | pl011_write(uap->im, uap, REG_IMSC); |
867b8e8e | 1707 | |
9f20e884 | 1708 | return request_irq(uap->port.irq, pl011_int, IRQF_SHARED, "uart-pl011", uap); |
867b8e8e AP |
1709 | } |
1710 | ||
1711 | /* | |
1712 | * Enable interrupts, only timeouts when using DMA | |
1713 | * if initial RX DMA job failed, start in interrupt mode | |
1714 | * as well. | |
1715 | */ | |
1716 | static void pl011_enable_interrupts(struct uart_amba_port *uap) | |
1717 | { | |
4a7e625c DM |
1718 | unsigned int i; |
1719 | ||
867b8e8e AP |
1720 | spin_lock_irq(&uap->port.lock); |
1721 | ||
1722 | /* Clear out any spuriously appearing RX interrupts */ | |
9f25bc51 | 1723 | pl011_write(UART011_RTIS | UART011_RXIS, uap, REG_ICR); |
4a7e625c DM |
1724 | |
1725 | /* | |
1726 | * RXIS is asserted only when the RX FIFO transitions from below | |
1727 | * to above the trigger threshold. If the RX FIFO is already | |
1728 | * full to the threshold this can't happen and RXIS will now be | |
1729 | * stuck off. Drain the RX FIFO explicitly to fix this: | |
1730 | */ | |
1731 | for (i = 0; i < uap->fifosize * 2; ++i) { | |
1732 | if (pl011_read(uap, REG_FR) & UART01x_FR_RXFE) | |
1733 | break; | |
1734 | ||
1735 | pl011_read(uap, REG_DR); | |
1736 | } | |
1737 | ||
867b8e8e AP |
1738 | uap->im = UART011_RTIM; |
1739 | if (!pl011_dma_rx_running(uap)) | |
1740 | uap->im |= UART011_RXIM; | |
9f25bc51 | 1741 | pl011_write(uap->im, uap, REG_IMSC); |
867b8e8e AP |
1742 | spin_unlock_irq(&uap->port.lock); |
1743 | } | |
1744 | ||
b3564c2c AV |
1745 | static int pl011_startup(struct uart_port *port) |
1746 | { | |
a5820c24 DT |
1747 | struct uart_amba_port *uap = |
1748 | container_of(port, struct uart_amba_port, port); | |
734745ca | 1749 | unsigned int cr; |
b3564c2c AV |
1750 | int retval; |
1751 | ||
1752 | retval = pl011_hwinit(port); | |
1753 | if (retval) | |
1754 | goto clk_dis; | |
1755 | ||
867b8e8e | 1756 | retval = pl011_allocate_irq(uap); |
1da177e4 LT |
1757 | if (retval) |
1758 | goto clk_dis; | |
1759 | ||
9f25bc51 | 1760 | pl011_write(uap->vendor->ifls, uap, REG_IFLS); |
1da177e4 | 1761 | |
734745ca | 1762 | spin_lock_irq(&uap->port.lock); |
570d2910 | 1763 | |
d8d8ffa4 SKS |
1764 | /* restore RTS and DTR */ |
1765 | cr = uap->old_cr & (UART011_CR_RTS | UART011_CR_DTR); | |
1766 | cr |= UART01x_CR_UARTEN | UART011_CR_RXE | UART011_CR_TXE; | |
9f25bc51 | 1767 | pl011_write(cr, uap, REG_CR); |
1da177e4 | 1768 | |
fe433907 JM |
1769 | spin_unlock_irq(&uap->port.lock); |
1770 | ||
1da177e4 LT |
1771 | /* |
1772 | * initialise the old status of the modem signals | |
1773 | */ | |
9f25bc51 | 1774 | uap->old_status = pl011_read(uap, REG_FR) & UART01x_FR_MODEM_ANY; |
1da177e4 | 1775 | |
68b65f73 RK |
1776 | /* Startup DMA */ |
1777 | pl011_dma_startup(uap); | |
1778 | ||
867b8e8e | 1779 | pl011_enable_interrupts(uap); |
1da177e4 LT |
1780 | |
1781 | return 0; | |
1782 | ||
1783 | clk_dis: | |
1c4c4394 | 1784 | clk_disable_unprepare(uap->clk); |
1da177e4 LT |
1785 | return retval; |
1786 | } | |
1787 | ||
0dd1e247 AP |
1788 | static int sbsa_uart_startup(struct uart_port *port) |
1789 | { | |
1790 | struct uart_amba_port *uap = | |
1791 | container_of(port, struct uart_amba_port, port); | |
1792 | int retval; | |
1793 | ||
1794 | retval = pl011_hwinit(port); | |
1795 | if (retval) | |
1796 | return retval; | |
1797 | ||
1798 | retval = pl011_allocate_irq(uap); | |
1799 | if (retval) | |
1800 | return retval; | |
1801 | ||
1802 | /* The SBSA UART does not support any modem status lines. */ | |
1803 | uap->old_status = 0; | |
1804 | ||
1805 | pl011_enable_interrupts(uap); | |
1806 | ||
1807 | return 0; | |
1808 | } | |
1809 | ||
ec489aa8 LW |
1810 | static void pl011_shutdown_channel(struct uart_amba_port *uap, |
1811 | unsigned int lcrh) | |
1812 | { | |
f11c9841 | 1813 | unsigned long val; |
ec489aa8 | 1814 | |
b2a4e24c | 1815 | val = pl011_read(uap, lcrh); |
f11c9841 | 1816 | val &= ~(UART01x_LCRH_BRK | UART01x_LCRH_FEN); |
b2a4e24c | 1817 | pl011_write(val, uap, lcrh); |
ec489aa8 LW |
1818 | } |
1819 | ||
95166a3f AP |
1820 | /* |
1821 | * disable the port. It should not disable RTS and DTR. | |
1822 | * Also RTS and DTR state should be preserved to restore | |
1823 | * it during startup(). | |
1824 | */ | |
1825 | static void pl011_disable_uart(struct uart_amba_port *uap) | |
1da177e4 | 1826 | { |
d8d8ffa4 | 1827 | unsigned int cr; |
1da177e4 | 1828 | |
2a76fa28 | 1829 | uap->port.status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS); |
fe433907 | 1830 | spin_lock_irq(&uap->port.lock); |
9f25bc51 | 1831 | cr = pl011_read(uap, REG_CR); |
d8d8ffa4 SKS |
1832 | uap->old_cr = cr; |
1833 | cr &= UART011_CR_RTS | UART011_CR_DTR; | |
1834 | cr |= UART01x_CR_UARTEN | UART011_CR_TXE; | |
9f25bc51 | 1835 | pl011_write(cr, uap, REG_CR); |
fe433907 | 1836 | spin_unlock_irq(&uap->port.lock); |
1da177e4 LT |
1837 | |
1838 | /* | |
1839 | * disable break condition and fifos | |
1840 | */ | |
e4df9a80 | 1841 | pl011_shutdown_channel(uap, REG_LCRH_RX); |
7fe9a5a9 | 1842 | if (pl011_split_lcrh(uap)) |
e4df9a80 | 1843 | pl011_shutdown_channel(uap, REG_LCRH_TX); |
95166a3f AP |
1844 | } |
1845 | ||
1846 | static void pl011_disable_interrupts(struct uart_amba_port *uap) | |
1847 | { | |
1848 | spin_lock_irq(&uap->port.lock); | |
1849 | ||
1850 | /* mask all interrupts and clear all pending ones */ | |
1851 | uap->im = 0; | |
9f25bc51 RK |
1852 | pl011_write(uap->im, uap, REG_IMSC); |
1853 | pl011_write(0xffff, uap, REG_ICR); | |
95166a3f AP |
1854 | |
1855 | spin_unlock_irq(&uap->port.lock); | |
1856 | } | |
1857 | ||
1858 | static void pl011_shutdown(struct uart_port *port) | |
1859 | { | |
1860 | struct uart_amba_port *uap = | |
1861 | container_of(port, struct uart_amba_port, port); | |
1862 | ||
1863 | pl011_disable_interrupts(uap); | |
1864 | ||
1865 | pl011_dma_shutdown(uap); | |
1866 | ||
1867 | free_irq(uap->port.irq, uap); | |
1868 | ||
1869 | pl011_disable_uart(uap); | |
1da177e4 LT |
1870 | |
1871 | /* | |
1872 | * Shut down the clock producer | |
1873 | */ | |
1c4c4394 | 1874 | clk_disable_unprepare(uap->clk); |
78d80c5a | 1875 | /* Optionally let pins go into sleep states */ |
2b996fc5 | 1876 | pinctrl_pm_select_sleep_state(port->dev); |
c16d51a3 | 1877 | |
574de559 | 1878 | if (dev_get_platdata(uap->port.dev)) { |
c16d51a3 SKS |
1879 | struct amba_pl011_data *plat; |
1880 | ||
574de559 | 1881 | plat = dev_get_platdata(uap->port.dev); |
c16d51a3 SKS |
1882 | if (plat->exit) |
1883 | plat->exit(); | |
1884 | } | |
1885 | ||
36f339d1 PH |
1886 | if (uap->port.ops->flush_buffer) |
1887 | uap->port.ops->flush_buffer(port); | |
1da177e4 LT |
1888 | } |
1889 | ||
0dd1e247 AP |
1890 | static void sbsa_uart_shutdown(struct uart_port *port) |
1891 | { | |
1892 | struct uart_amba_port *uap = | |
1893 | container_of(port, struct uart_amba_port, port); | |
1894 | ||
1895 | pl011_disable_interrupts(uap); | |
1896 | ||
1897 | free_irq(uap->port.irq, uap); | |
1898 | ||
1899 | if (uap->port.ops->flush_buffer) | |
1900 | uap->port.ops->flush_buffer(port); | |
1901 | } | |
1902 | ||
ef5a9358 AP |
1903 | static void |
1904 | pl011_setup_status_masks(struct uart_port *port, struct ktermios *termios) | |
1905 | { | |
1906 | port->read_status_mask = UART011_DR_OE | 255; | |
1907 | if (termios->c_iflag & INPCK) | |
1908 | port->read_status_mask |= UART011_DR_FE | UART011_DR_PE; | |
1909 | if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK)) | |
1910 | port->read_status_mask |= UART011_DR_BE; | |
1911 | ||
1912 | /* | |
1913 | * Characters to ignore | |
1914 | */ | |
1915 | port->ignore_status_mask = 0; | |
1916 | if (termios->c_iflag & IGNPAR) | |
1917 | port->ignore_status_mask |= UART011_DR_FE | UART011_DR_PE; | |
1918 | if (termios->c_iflag & IGNBRK) { | |
1919 | port->ignore_status_mask |= UART011_DR_BE; | |
1920 | /* | |
1921 | * If we're ignoring parity and break indicators, | |
1922 | * ignore overruns too (for real raw support). | |
1923 | */ | |
1924 | if (termios->c_iflag & IGNPAR) | |
1925 | port->ignore_status_mask |= UART011_DR_OE; | |
1926 | } | |
1927 | ||
1928 | /* | |
1929 | * Ignore all characters if CREAD is not set. | |
1930 | */ | |
1931 | if ((termios->c_cflag & CREAD) == 0) | |
1932 | port->ignore_status_mask |= UART_DUMMY_DR_RX; | |
1933 | } | |
1934 | ||
1da177e4 | 1935 | static void |
606d099c AC |
1936 | pl011_set_termios(struct uart_port *port, struct ktermios *termios, |
1937 | struct ktermios *old) | |
1da177e4 | 1938 | { |
a5820c24 DT |
1939 | struct uart_amba_port *uap = |
1940 | container_of(port, struct uart_amba_port, port); | |
1da177e4 LT |
1941 | unsigned int lcr_h, old_cr; |
1942 | unsigned long flags; | |
c19f12b5 RK |
1943 | unsigned int baud, quot, clkdiv; |
1944 | ||
1945 | if (uap->vendor->oversampling) | |
1946 | clkdiv = 8; | |
1947 | else | |
1948 | clkdiv = 16; | |
1da177e4 LT |
1949 | |
1950 | /* | |
1951 | * Ask the core to calculate the divisor for us. | |
1952 | */ | |
ac3e3fb4 | 1953 | baud = uart_get_baud_rate(port, termios, old, 0, |
c19f12b5 | 1954 | port->uartclk / clkdiv); |
89fa28db | 1955 | #ifdef CONFIG_DMA_ENGINE |
cb06ff10 CM |
1956 | /* |
1957 | * Adjust RX DMA polling rate with baud rate if not specified. | |
1958 | */ | |
1959 | if (uap->dmarx.auto_poll_rate) | |
1960 | uap->dmarx.poll_rate = DIV_ROUND_UP(10000000, baud); | |
89fa28db | 1961 | #endif |
ac3e3fb4 LW |
1962 | |
1963 | if (baud > port->uartclk/16) | |
1964 | quot = DIV_ROUND_CLOSEST(port->uartclk * 8, baud); | |
1965 | else | |
1966 | quot = DIV_ROUND_CLOSEST(port->uartclk * 4, baud); | |
1da177e4 LT |
1967 | |
1968 | switch (termios->c_cflag & CSIZE) { | |
1969 | case CS5: | |
1970 | lcr_h = UART01x_LCRH_WLEN_5; | |
1971 | break; | |
1972 | case CS6: | |
1973 | lcr_h = UART01x_LCRH_WLEN_6; | |
1974 | break; | |
1975 | case CS7: | |
1976 | lcr_h = UART01x_LCRH_WLEN_7; | |
1977 | break; | |
1978 | default: // CS8 | |
1979 | lcr_h = UART01x_LCRH_WLEN_8; | |
1980 | break; | |
1981 | } | |
1982 | if (termios->c_cflag & CSTOPB) | |
1983 | lcr_h |= UART01x_LCRH_STP2; | |
1984 | if (termios->c_cflag & PARENB) { | |
1985 | lcr_h |= UART01x_LCRH_PEN; | |
1986 | if (!(termios->c_cflag & PARODD)) | |
1987 | lcr_h |= UART01x_LCRH_EPS; | |
bb70002c ES |
1988 | if (termios->c_cflag & CMSPAR) |
1989 | lcr_h |= UART011_LCRH_SPS; | |
1da177e4 | 1990 | } |
ffca2b11 | 1991 | if (uap->fifosize > 1) |
1da177e4 LT |
1992 | lcr_h |= UART01x_LCRH_FEN; |
1993 | ||
1994 | spin_lock_irqsave(&port->lock, flags); | |
1995 | ||
1996 | /* | |
1997 | * Update the per-port timeout. | |
1998 | */ | |
1999 | uart_update_timeout(port, termios->c_cflag, baud); | |
2000 | ||
ef5a9358 | 2001 | pl011_setup_status_masks(port, termios); |
1da177e4 LT |
2002 | |
2003 | if (UART_ENABLE_MS(port, termios->c_cflag)) | |
2004 | pl011_enable_ms(port); | |
2005 | ||
2006 | /* first, disable everything */ | |
9f25bc51 RK |
2007 | old_cr = pl011_read(uap, REG_CR); |
2008 | pl011_write(0, uap, REG_CR); | |
1da177e4 | 2009 | |
3b43816f RV |
2010 | if (termios->c_cflag & CRTSCTS) { |
2011 | if (old_cr & UART011_CR_RTS) | |
2012 | old_cr |= UART011_CR_RTSEN; | |
2013 | ||
2014 | old_cr |= UART011_CR_CTSEN; | |
2a76fa28 | 2015 | port->status |= UPSTAT_AUTOCTS | UPSTAT_AUTORTS; |
3b43816f RV |
2016 | } else { |
2017 | old_cr &= ~(UART011_CR_CTSEN | UART011_CR_RTSEN); | |
2a76fa28 | 2018 | port->status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS); |
3b43816f RV |
2019 | } |
2020 | ||
c19f12b5 RK |
2021 | if (uap->vendor->oversampling) { |
2022 | if (baud > port->uartclk / 16) | |
ac3e3fb4 LW |
2023 | old_cr |= ST_UART011_CR_OVSFACT; |
2024 | else | |
2025 | old_cr &= ~ST_UART011_CR_OVSFACT; | |
2026 | } | |
2027 | ||
c5dd553b LW |
2028 | /* |
2029 | * Workaround for the ST Micro oversampling variants to | |
2030 | * increase the bitrate slightly, by lowering the divisor, | |
2031 | * to avoid delayed sampling of start bit at high speeds, | |
2032 | * else we see data corruption. | |
2033 | */ | |
2034 | if (uap->vendor->oversampling) { | |
2035 | if ((baud >= 3000000) && (baud < 3250000) && (quot > 1)) | |
2036 | quot -= 1; | |
2037 | else if ((baud > 3250000) && (quot > 2)) | |
2038 | quot -= 2; | |
2039 | } | |
1da177e4 | 2040 | /* Set baud rate */ |
9f25bc51 RK |
2041 | pl011_write(quot & 0x3f, uap, REG_FBRD); |
2042 | pl011_write(quot >> 6, uap, REG_IBRD); | |
1da177e4 LT |
2043 | |
2044 | /* | |
2045 | * ----------v----------v----------v----------v----- | |
e4df9a80 | 2046 | * NOTE: REG_LCRH_TX and REG_LCRH_RX MUST BE WRITTEN AFTER |
9f25bc51 | 2047 | * REG_FBRD & REG_IBRD. |
1da177e4 LT |
2048 | * ----------^----------^----------^----------^----- |
2049 | */ | |
b60f2f66 | 2050 | pl011_write_lcr_h(uap, lcr_h); |
9f25bc51 | 2051 | pl011_write(old_cr, uap, REG_CR); |
1da177e4 LT |
2052 | |
2053 | spin_unlock_irqrestore(&port->lock, flags); | |
2054 | } | |
2055 | ||
0dd1e247 AP |
2056 | static void |
2057 | sbsa_uart_set_termios(struct uart_port *port, struct ktermios *termios, | |
2058 | struct ktermios *old) | |
2059 | { | |
2060 | struct uart_amba_port *uap = | |
2061 | container_of(port, struct uart_amba_port, port); | |
2062 | unsigned long flags; | |
2063 | ||
2064 | tty_termios_encode_baud_rate(termios, uap->fixed_baud, uap->fixed_baud); | |
2065 | ||
2066 | /* The SBSA UART only supports 8n1 without hardware flow control. */ | |
2067 | termios->c_cflag &= ~(CSIZE | CSTOPB | PARENB | PARODD); | |
2068 | termios->c_cflag &= ~(CMSPAR | CRTSCTS); | |
2069 | termios->c_cflag |= CS8 | CLOCAL; | |
2070 | ||
2071 | spin_lock_irqsave(&port->lock, flags); | |
2072 | uart_update_timeout(port, CS8, uap->fixed_baud); | |
2073 | pl011_setup_status_masks(port, termios); | |
2074 | spin_unlock_irqrestore(&port->lock, flags); | |
2075 | } | |
2076 | ||
1da177e4 LT |
2077 | static const char *pl011_type(struct uart_port *port) |
2078 | { | |
a5820c24 DT |
2079 | struct uart_amba_port *uap = |
2080 | container_of(port, struct uart_amba_port, port); | |
e8a7ba86 | 2081 | return uap->port.type == PORT_AMBA ? uap->type : NULL; |
1da177e4 LT |
2082 | } |
2083 | ||
2084 | /* | |
2085 | * Release the memory region(s) being used by 'port' | |
2086 | */ | |
e643f87f | 2087 | static void pl011_release_port(struct uart_port *port) |
1da177e4 LT |
2088 | { |
2089 | release_mem_region(port->mapbase, SZ_4K); | |
2090 | } | |
2091 | ||
2092 | /* | |
2093 | * Request the memory region(s) being used by 'port' | |
2094 | */ | |
e643f87f | 2095 | static int pl011_request_port(struct uart_port *port) |
1da177e4 LT |
2096 | { |
2097 | return request_mem_region(port->mapbase, SZ_4K, "uart-pl011") | |
2098 | != NULL ? 0 : -EBUSY; | |
2099 | } | |
2100 | ||
2101 | /* | |
2102 | * Configure/autoconfigure the port. | |
2103 | */ | |
e643f87f | 2104 | static void pl011_config_port(struct uart_port *port, int flags) |
1da177e4 LT |
2105 | { |
2106 | if (flags & UART_CONFIG_TYPE) { | |
2107 | port->type = PORT_AMBA; | |
e643f87f | 2108 | pl011_request_port(port); |
1da177e4 LT |
2109 | } |
2110 | } | |
2111 | ||
2112 | /* | |
2113 | * verify the new serial_struct (for TIOCSSERIAL). | |
2114 | */ | |
e643f87f | 2115 | static int pl011_verify_port(struct uart_port *port, struct serial_struct *ser) |
1da177e4 LT |
2116 | { |
2117 | int ret = 0; | |
2118 | if (ser->type != PORT_UNKNOWN && ser->type != PORT_AMBA) | |
2119 | ret = -EINVAL; | |
a62c4133 | 2120 | if (ser->irq < 0 || ser->irq >= nr_irqs) |
1da177e4 LT |
2121 | ret = -EINVAL; |
2122 | if (ser->baud_base < 9600) | |
2123 | ret = -EINVAL; | |
2124 | return ret; | |
2125 | } | |
2126 | ||
2331e068 | 2127 | static const struct uart_ops amba_pl011_pops = { |
e643f87f | 2128 | .tx_empty = pl011_tx_empty, |
1da177e4 | 2129 | .set_mctrl = pl011_set_mctrl, |
e643f87f | 2130 | .get_mctrl = pl011_get_mctrl, |
1da177e4 LT |
2131 | .stop_tx = pl011_stop_tx, |
2132 | .start_tx = pl011_start_tx, | |
2133 | .stop_rx = pl011_stop_rx, | |
2134 | .enable_ms = pl011_enable_ms, | |
2135 | .break_ctl = pl011_break_ctl, | |
2136 | .startup = pl011_startup, | |
2137 | .shutdown = pl011_shutdown, | |
68b65f73 | 2138 | .flush_buffer = pl011_dma_flush_buffer, |
1da177e4 LT |
2139 | .set_termios = pl011_set_termios, |
2140 | .type = pl011_type, | |
e643f87f LW |
2141 | .release_port = pl011_release_port, |
2142 | .request_port = pl011_request_port, | |
2143 | .config_port = pl011_config_port, | |
2144 | .verify_port = pl011_verify_port, | |
84b5ae15 | 2145 | #ifdef CONFIG_CONSOLE_POLL |
b3564c2c | 2146 | .poll_init = pl011_hwinit, |
e643f87f LW |
2147 | .poll_get_char = pl011_get_poll_char, |
2148 | .poll_put_char = pl011_put_poll_char, | |
84b5ae15 | 2149 | #endif |
1da177e4 LT |
2150 | }; |
2151 | ||
0dd1e247 AP |
2152 | static void sbsa_uart_set_mctrl(struct uart_port *port, unsigned int mctrl) |
2153 | { | |
2154 | } | |
2155 | ||
2156 | static unsigned int sbsa_uart_get_mctrl(struct uart_port *port) | |
2157 | { | |
2158 | return 0; | |
2159 | } | |
2160 | ||
2161 | static const struct uart_ops sbsa_uart_pops = { | |
2162 | .tx_empty = pl011_tx_empty, | |
2163 | .set_mctrl = sbsa_uart_set_mctrl, | |
2164 | .get_mctrl = sbsa_uart_get_mctrl, | |
2165 | .stop_tx = pl011_stop_tx, | |
2166 | .start_tx = pl011_start_tx, | |
2167 | .stop_rx = pl011_stop_rx, | |
2168 | .startup = sbsa_uart_startup, | |
2169 | .shutdown = sbsa_uart_shutdown, | |
2170 | .set_termios = sbsa_uart_set_termios, | |
2171 | .type = pl011_type, | |
2172 | .release_port = pl011_release_port, | |
2173 | .request_port = pl011_request_port, | |
2174 | .config_port = pl011_config_port, | |
2175 | .verify_port = pl011_verify_port, | |
2176 | #ifdef CONFIG_CONSOLE_POLL | |
2177 | .poll_init = pl011_hwinit, | |
2178 | .poll_get_char = pl011_get_poll_char, | |
2179 | .poll_put_char = pl011_put_poll_char, | |
2180 | #endif | |
2181 | }; | |
2182 | ||
1da177e4 LT |
2183 | static struct uart_amba_port *amba_ports[UART_NR]; |
2184 | ||
2185 | #ifdef CONFIG_SERIAL_AMBA_PL011_CONSOLE | |
2186 | ||
d358788f | 2187 | static void pl011_console_putchar(struct uart_port *port, int ch) |
1da177e4 | 2188 | { |
a5820c24 DT |
2189 | struct uart_amba_port *uap = |
2190 | container_of(port, struct uart_amba_port, port); | |
1da177e4 | 2191 | |
9f25bc51 | 2192 | while (pl011_read(uap, REG_FR) & UART01x_FR_TXFF) |
2f2fd089 | 2193 | cpu_relax(); |
9f25bc51 | 2194 | pl011_write(ch, uap, REG_DR); |
1da177e4 LT |
2195 | } |
2196 | ||
2197 | static void | |
2198 | pl011_console_write(struct console *co, const char *s, unsigned int count) | |
2199 | { | |
2200 | struct uart_amba_port *uap = amba_ports[co->index]; | |
2f2fd089 | 2201 | unsigned int old_cr = 0, new_cr; |
ef605fdb RV |
2202 | unsigned long flags; |
2203 | int locked = 1; | |
1da177e4 LT |
2204 | |
2205 | clk_enable(uap->clk); | |
2206 | ||
ef605fdb RV |
2207 | local_irq_save(flags); |
2208 | if (uap->port.sysrq) | |
2209 | locked = 0; | |
2210 | else if (oops_in_progress) | |
2211 | locked = spin_trylock(&uap->port.lock); | |
2212 | else | |
2213 | spin_lock(&uap->port.lock); | |
2214 | ||
1da177e4 LT |
2215 | /* |
2216 | * First save the CR then disable the interrupts | |
2217 | */ | |
71eec483 | 2218 | if (!uap->vendor->always_enabled) { |
9f25bc51 | 2219 | old_cr = pl011_read(uap, REG_CR); |
71eec483 AP |
2220 | new_cr = old_cr & ~UART011_CR_CTSEN; |
2221 | new_cr |= UART01x_CR_UARTEN | UART011_CR_TXE; | |
9f25bc51 | 2222 | pl011_write(new_cr, uap, REG_CR); |
71eec483 | 2223 | } |
1da177e4 | 2224 | |
d358788f | 2225 | uart_console_write(&uap->port, s, count, pl011_console_putchar); |
1da177e4 LT |
2226 | |
2227 | /* | |
d8a4995b CC |
2228 | * Finally, wait for transmitter to become empty and restore the |
2229 | * TCR. Allow feature register bits to be inverted to work around | |
2230 | * errata. | |
1da177e4 | 2231 | */ |
d8a4995b CC |
2232 | while ((pl011_read(uap, REG_FR) ^ uap->vendor->inv_fr) |
2233 | & uap->vendor->fr_busy) | |
2f2fd089 | 2234 | cpu_relax(); |
71eec483 | 2235 | if (!uap->vendor->always_enabled) |
9f25bc51 | 2236 | pl011_write(old_cr, uap, REG_CR); |
1da177e4 | 2237 | |
ef605fdb RV |
2238 | if (locked) |
2239 | spin_unlock(&uap->port.lock); | |
2240 | local_irq_restore(flags); | |
2241 | ||
1da177e4 LT |
2242 | clk_disable(uap->clk); |
2243 | } | |
2244 | ||
27afac93 LW |
2245 | static void pl011_console_get_options(struct uart_amba_port *uap, int *baud, |
2246 | int *parity, int *bits) | |
1da177e4 | 2247 | { |
9f25bc51 | 2248 | if (pl011_read(uap, REG_CR) & UART01x_CR_UARTEN) { |
1da177e4 LT |
2249 | unsigned int lcr_h, ibrd, fbrd; |
2250 | ||
e4df9a80 | 2251 | lcr_h = pl011_read(uap, REG_LCRH_TX); |
1da177e4 LT |
2252 | |
2253 | *parity = 'n'; | |
2254 | if (lcr_h & UART01x_LCRH_PEN) { | |
2255 | if (lcr_h & UART01x_LCRH_EPS) | |
2256 | *parity = 'e'; | |
2257 | else | |
2258 | *parity = 'o'; | |
2259 | } | |
2260 | ||
2261 | if ((lcr_h & 0x60) == UART01x_LCRH_WLEN_7) | |
2262 | *bits = 7; | |
2263 | else | |
2264 | *bits = 8; | |
2265 | ||
9f25bc51 RK |
2266 | ibrd = pl011_read(uap, REG_IBRD); |
2267 | fbrd = pl011_read(uap, REG_FBRD); | |
1da177e4 LT |
2268 | |
2269 | *baud = uap->port.uartclk * 4 / (64 * ibrd + fbrd); | |
ac3e3fb4 | 2270 | |
c19f12b5 | 2271 | if (uap->vendor->oversampling) { |
9f25bc51 | 2272 | if (pl011_read(uap, REG_CR) |
ac3e3fb4 LW |
2273 | & ST_UART011_CR_OVSFACT) |
2274 | *baud *= 2; | |
2275 | } | |
1da177e4 LT |
2276 | } |
2277 | } | |
2278 | ||
27afac93 | 2279 | static int pl011_console_setup(struct console *co, char *options) |
1da177e4 LT |
2280 | { |
2281 | struct uart_amba_port *uap; | |
2282 | int baud = 38400; | |
2283 | int bits = 8; | |
2284 | int parity = 'n'; | |
2285 | int flow = 'n'; | |
4b4851c6 | 2286 | int ret; |
1da177e4 LT |
2287 | |
2288 | /* | |
2289 | * Check whether an invalid uart number has been specified, and | |
2290 | * if so, search for the first available port that does have | |
2291 | * console support. | |
2292 | */ | |
2293 | if (co->index >= UART_NR) | |
2294 | co->index = 0; | |
2295 | uap = amba_ports[co->index]; | |
d28122a5 RK |
2296 | if (!uap) |
2297 | return -ENODEV; | |
1da177e4 | 2298 | |
78d80c5a | 2299 | /* Allow pins to be muxed in and configured */ |
2b996fc5 | 2300 | pinctrl_pm_select_default_state(uap->port.dev); |
78d80c5a | 2301 | |
4b4851c6 RK |
2302 | ret = clk_prepare(uap->clk); |
2303 | if (ret) | |
2304 | return ret; | |
2305 | ||
574de559 | 2306 | if (dev_get_platdata(uap->port.dev)) { |
c16d51a3 SKS |
2307 | struct amba_pl011_data *plat; |
2308 | ||
574de559 | 2309 | plat = dev_get_platdata(uap->port.dev); |
c16d51a3 SKS |
2310 | if (plat->init) |
2311 | plat->init(); | |
2312 | } | |
2313 | ||
1da177e4 LT |
2314 | uap->port.uartclk = clk_get_rate(uap->clk); |
2315 | ||
cefc2d1d AP |
2316 | if (uap->vendor->fixed_options) { |
2317 | baud = uap->fixed_baud; | |
2318 | } else { | |
2319 | if (options) | |
2320 | uart_parse_options(options, | |
2321 | &baud, &parity, &bits, &flow); | |
2322 | else | |
2323 | pl011_console_get_options(uap, &baud, &parity, &bits); | |
2324 | } | |
1da177e4 LT |
2325 | |
2326 | return uart_set_options(&uap->port, co, baud, parity, bits, flow); | |
2327 | } | |
2328 | ||
10879ae5 AM |
2329 | /** |
2330 | * pl011_console_match - non-standard console matching | |
2331 | * @co: registering console | |
2332 | * @name: name from console command line | |
2333 | * @idx: index from console command line | |
2334 | * @options: ptr to option string from console command line | |
2335 | * | |
2336 | * Only attempts to match console command lines of the form: | |
2337 | * console=pl011,mmio|mmio32,<addr>[,<options>] | |
2338 | * console=pl011,0x<addr>[,<options>] | |
2339 | * This form is used to register an initial earlycon boot console and | |
2340 | * replace it with the amba_console at pl011 driver init. | |
2341 | * | |
2342 | * Performs console setup for a match (as required by interface) | |
2343 | * If no <options> are specified, then assume the h/w is already setup. | |
2344 | * | |
2345 | * Returns 0 if console matches; otherwise non-zero to use default matching | |
2346 | */ | |
27afac93 LW |
2347 | static int pl011_console_match(struct console *co, char *name, int idx, |
2348 | char *options) | |
10879ae5 AM |
2349 | { |
2350 | unsigned char iotype; | |
2351 | resource_size_t addr; | |
2352 | int i; | |
2353 | ||
37ef38f3 TT |
2354 | /* |
2355 | * Systems affected by the Qualcomm Technologies QDF2400 E44 erratum | |
2356 | * have a distinct console name, so make sure we check for that. | |
2357 | * The actual implementation of the erratum occurs in the probe | |
2358 | * function. | |
2359 | */ | |
2360 | if ((strcmp(name, "qdf2400_e44") != 0) && (strcmp(name, "pl011") != 0)) | |
10879ae5 AM |
2361 | return -ENODEV; |
2362 | ||
2363 | if (uart_parse_earlycon(options, &iotype, &addr, &options)) | |
2364 | return -ENODEV; | |
2365 | ||
2366 | if (iotype != UPIO_MEM && iotype != UPIO_MEM32) | |
2367 | return -ENODEV; | |
2368 | ||
2369 | /* try to match the port specified on the command line */ | |
2370 | for (i = 0; i < ARRAY_SIZE(amba_ports); i++) { | |
2371 | struct uart_port *port; | |
2372 | ||
2373 | if (!amba_ports[i]) | |
2374 | continue; | |
2375 | ||
2376 | port = &amba_ports[i]->port; | |
2377 | ||
2378 | if (port->mapbase != addr) | |
2379 | continue; | |
2380 | ||
2381 | co->index = i; | |
2382 | port->cons = co; | |
2383 | return pl011_console_setup(co, options); | |
2384 | } | |
2385 | ||
2386 | return -ENODEV; | |
2387 | } | |
2388 | ||
2d93486c | 2389 | static struct uart_driver amba_reg; |
1da177e4 LT |
2390 | static struct console amba_console = { |
2391 | .name = "ttyAMA", | |
2392 | .write = pl011_console_write, | |
2393 | .device = uart_console_device, | |
2394 | .setup = pl011_console_setup, | |
10879ae5 | 2395 | .match = pl011_console_match, |
7951ffc9 | 2396 | .flags = CON_PRINTBUFFER | CON_ANYTIME, |
1da177e4 LT |
2397 | .index = -1, |
2398 | .data = &amba_reg, | |
2399 | }; | |
2400 | ||
2401 | #define AMBA_CONSOLE (&amba_console) | |
0d3c673e | 2402 | |
d8a4995b CC |
2403 | static void qdf2400_e44_putc(struct uart_port *port, int c) |
2404 | { | |
2405 | while (readl(port->membase + UART01x_FR) & UART01x_FR_TXFF) | |
2406 | cpu_relax(); | |
2407 | writel(c, port->membase + UART01x_DR); | |
2408 | while (!(readl(port->membase + UART01x_FR) & UART011_FR_TXFE)) | |
2409 | cpu_relax(); | |
2410 | } | |
2411 | ||
2412 | static void qdf2400_e44_early_write(struct console *con, const char *s, unsigned n) | |
2413 | { | |
2414 | struct earlycon_device *dev = con->data; | |
2415 | ||
2416 | uart_console_write(&dev->port, s, n, qdf2400_e44_putc); | |
2417 | } | |
2418 | ||
0d3c673e RH |
2419 | static void pl011_putc(struct uart_port *port, int c) |
2420 | { | |
cdf091ca | 2421 | while (readl(port->membase + UART01x_FR) & UART01x_FR_TXFF) |
2f2fd089 | 2422 | cpu_relax(); |
3b78fae7 TT |
2423 | if (port->iotype == UPIO_MEM32) |
2424 | writel(c, port->membase + UART01x_DR); | |
2425 | else | |
2426 | writeb(c, port->membase + UART01x_DR); | |
e06690bf | 2427 | while (readl(port->membase + UART01x_FR) & UART01x_FR_BUSY) |
2f2fd089 | 2428 | cpu_relax(); |
0d3c673e RH |
2429 | } |
2430 | ||
2431 | static void pl011_early_write(struct console *con, const char *s, unsigned n) | |
2432 | { | |
2433 | struct earlycon_device *dev = con->data; | |
2434 | ||
2435 | uart_console_write(&dev->port, s, n, pl011_putc); | |
2436 | } | |
2437 | ||
195867ff SG |
2438 | #ifdef CONFIG_CONSOLE_POLL |
2439 | static int pl011_getc(struct uart_port *port) | |
2440 | { | |
2441 | if (readl(port->membase + UART01x_FR) & UART01x_FR_RXFE) | |
2442 | return NO_POLL_CHAR; | |
2443 | ||
2444 | if (port->iotype == UPIO_MEM32) | |
2445 | return readl(port->membase + UART01x_DR); | |
2446 | else | |
2447 | return readb(port->membase + UART01x_DR); | |
2448 | } | |
2449 | ||
2450 | static int pl011_early_read(struct console *con, char *s, unsigned int n) | |
2451 | { | |
2452 | struct earlycon_device *dev = con->data; | |
2453 | int ch, num_read = 0; | |
2454 | ||
2455 | while (num_read < n) { | |
2456 | ch = pl011_getc(&dev->port); | |
2457 | if (ch == NO_POLL_CHAR) | |
2458 | break; | |
2459 | ||
2460 | s[num_read++] = ch; | |
2461 | } | |
2462 | ||
2463 | return num_read; | |
2464 | } | |
2465 | #else | |
2466 | #define pl011_early_read NULL | |
2467 | #endif | |
2468 | ||
e53e597f TT |
2469 | /* |
2470 | * On non-ACPI systems, earlycon is enabled by specifying | |
2471 | * "earlycon=pl011,<address>" on the kernel command line. | |
2472 | * | |
2473 | * On ACPI ARM64 systems, an "early" console is enabled via the SPCR table, | |
2474 | * by specifying only "earlycon" on the command line. Because it requires | |
2475 | * SPCR, the console starts after ACPI is parsed, which is later than a | |
2476 | * traditional early console. | |
2477 | * | |
2478 | * To get the traditional early console that starts before ACPI is parsed, | |
2479 | * specify the full "earlycon=pl011,<address>" option. | |
2480 | */ | |
0d3c673e RH |
2481 | static int __init pl011_early_console_setup(struct earlycon_device *device, |
2482 | const char *opt) | |
2483 | { | |
2484 | if (!device->port.membase) | |
2485 | return -ENODEV; | |
2486 | ||
5a0722b8 | 2487 | device->con->write = pl011_early_write; |
195867ff | 2488 | device->con->read = pl011_early_read; |
e53e597f | 2489 | |
0d3c673e RH |
2490 | return 0; |
2491 | } | |
45e0f0f5 | 2492 | OF_EARLYCON_DECLARE(pl011, "arm,pl011", pl011_early_console_setup); |
fcb32159 | 2493 | OF_EARLYCON_DECLARE(pl011, "arm,sbsa-uart", pl011_early_console_setup); |
5a0722b8 TT |
2494 | |
2495 | /* | |
2496 | * On Qualcomm Datacenter Technologies QDF2400 SOCs affected by | |
2497 | * Erratum 44, traditional earlycon can be enabled by specifying | |
2498 | * "earlycon=qdf2400_e44,<address>". Any options are ignored. | |
2499 | * | |
2500 | * Alternatively, you can just specify "earlycon", and the early console | |
2501 | * will be enabled with the information from the SPCR table. In this | |
2502 | * case, the SPCR code will detect the need for the E44 work-around, | |
2503 | * and set the console name to "qdf2400_e44". | |
2504 | */ | |
2505 | static int __init | |
2506 | qdf2400_e44_early_console_setup(struct earlycon_device *device, | |
2507 | const char *opt) | |
2508 | { | |
2509 | if (!device->port.membase) | |
2510 | return -ENODEV; | |
2511 | ||
2512 | device->con->write = qdf2400_e44_early_write; | |
2513 | return 0; | |
2514 | } | |
2515 | EARLYCON_DECLARE(qdf2400_e44, qdf2400_e44_early_console_setup); | |
0d3c673e | 2516 | |
1da177e4 LT |
2517 | #else |
2518 | #define AMBA_CONSOLE NULL | |
2519 | #endif | |
2520 | ||
2521 | static struct uart_driver amba_reg = { | |
2522 | .owner = THIS_MODULE, | |
2523 | .driver_name = "ttyAMA", | |
2524 | .dev_name = "ttyAMA", | |
2525 | .major = SERIAL_AMBA_MAJOR, | |
2526 | .minor = SERIAL_AMBA_MINOR, | |
2527 | .nr = UART_NR, | |
2528 | .cons = AMBA_CONSOLE, | |
2529 | }; | |
2530 | ||
32614aad ML |
2531 | static int pl011_probe_dt_alias(int index, struct device *dev) |
2532 | { | |
2533 | struct device_node *np; | |
2534 | static bool seen_dev_with_alias = false; | |
2535 | static bool seen_dev_without_alias = false; | |
2536 | int ret = index; | |
2537 | ||
2538 | if (!IS_ENABLED(CONFIG_OF)) | |
2539 | return ret; | |
2540 | ||
2541 | np = dev->of_node; | |
2542 | if (!np) | |
2543 | return ret; | |
2544 | ||
2545 | ret = of_alias_get_id(np, "serial"); | |
287980e4 | 2546 | if (ret < 0) { |
32614aad ML |
2547 | seen_dev_without_alias = true; |
2548 | ret = index; | |
2549 | } else { | |
2550 | seen_dev_with_alias = true; | |
2551 | if (ret >= ARRAY_SIZE(amba_ports) || amba_ports[ret] != NULL) { | |
2552 | dev_warn(dev, "requested serial port %d not available.\n", ret); | |
2553 | ret = index; | |
2554 | } | |
2555 | } | |
2556 | ||
2557 | if (seen_dev_with_alias && seen_dev_without_alias) | |
2558 | dev_warn(dev, "aliased and non-aliased serial devices found in device tree. Serial port enumeration may be unpredictable.\n"); | |
2559 | ||
2560 | return ret; | |
2561 | } | |
2562 | ||
49bb3c86 AP |
2563 | /* unregisters the driver also if no more ports are left */ |
2564 | static void pl011_unregister_port(struct uart_amba_port *uap) | |
2565 | { | |
2566 | int i; | |
2567 | bool busy = false; | |
2568 | ||
2569 | for (i = 0; i < ARRAY_SIZE(amba_ports); i++) { | |
2570 | if (amba_ports[i] == uap) | |
2571 | amba_ports[i] = NULL; | |
2572 | else if (amba_ports[i]) | |
2573 | busy = true; | |
2574 | } | |
2575 | pl011_dma_remove(uap); | |
2576 | if (!busy) | |
2577 | uart_unregister_driver(&amba_reg); | |
2578 | } | |
2579 | ||
3873e2d7 | 2580 | static int pl011_find_free_port(void) |
1da177e4 | 2581 | { |
3873e2d7 | 2582 | int i; |
1da177e4 LT |
2583 | |
2584 | for (i = 0; i < ARRAY_SIZE(amba_ports); i++) | |
2585 | if (amba_ports[i] == NULL) | |
3873e2d7 | 2586 | return i; |
1da177e4 | 2587 | |
3873e2d7 AP |
2588 | return -EBUSY; |
2589 | } | |
1da177e4 | 2590 | |
3873e2d7 AP |
2591 | static int pl011_setup_port(struct device *dev, struct uart_amba_port *uap, |
2592 | struct resource *mmiobase, int index) | |
2593 | { | |
2594 | void __iomem *base; | |
32614aad | 2595 | |
3873e2d7 | 2596 | base = devm_ioremap_resource(dev, mmiobase); |
97a60eac KK |
2597 | if (IS_ERR(base)) |
2598 | return PTR_ERR(base); | |
1da177e4 | 2599 | |
3873e2d7 | 2600 | index = pl011_probe_dt_alias(index, dev); |
1da177e4 | 2601 | |
d8d8ffa4 | 2602 | uap->old_cr = 0; |
3873e2d7 AP |
2603 | uap->port.dev = dev; |
2604 | uap->port.mapbase = mmiobase->start; | |
1da177e4 | 2605 | uap->port.membase = base; |
ffca2b11 | 2606 | uap->port.fifosize = uap->fifosize; |
5f99fca9 | 2607 | uap->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_AMBA_PL011_CONSOLE); |
1da177e4 | 2608 | uap->port.flags = UPF_BOOT_AUTOCONF; |
3873e2d7 | 2609 | uap->port.line = index; |
1da177e4 | 2610 | |
3873e2d7 | 2611 | amba_ports[index] = uap; |
c3d8b76f | 2612 | |
3873e2d7 AP |
2613 | return 0; |
2614 | } | |
e8a7ba86 | 2615 | |
3873e2d7 AP |
2616 | static int pl011_register_port(struct uart_amba_port *uap) |
2617 | { | |
89efbe70 | 2618 | int ret, i; |
1da177e4 | 2619 | |
3873e2d7 | 2620 | /* Ensure interrupts from this UART are masked and cleared */ |
9f25bc51 RK |
2621 | pl011_write(0, uap, REG_IMSC); |
2622 | pl011_write(0xffff, uap, REG_ICR); | |
ef2889f7 TB |
2623 | |
2624 | if (!amba_reg.state) { | |
2625 | ret = uart_register_driver(&amba_reg); | |
2626 | if (ret < 0) { | |
3873e2d7 | 2627 | dev_err(uap->port.dev, |
1c9be310 | 2628 | "Failed to register AMBA-PL011 driver\n"); |
89efbe70 LW |
2629 | for (i = 0; i < ARRAY_SIZE(amba_ports); i++) |
2630 | if (amba_ports[i] == uap) | |
2631 | amba_ports[i] = NULL; | |
ef2889f7 TB |
2632 | return ret; |
2633 | } | |
2634 | } | |
2635 | ||
1da177e4 | 2636 | ret = uart_add_one_port(&amba_reg, &uap->port); |
49bb3c86 AP |
2637 | if (ret) |
2638 | pl011_unregister_port(uap); | |
7f6d942a | 2639 | |
1da177e4 LT |
2640 | return ret; |
2641 | } | |
2642 | ||
3873e2d7 AP |
2643 | static int pl011_probe(struct amba_device *dev, const struct amba_id *id) |
2644 | { | |
2645 | struct uart_amba_port *uap; | |
2646 | struct vendor_data *vendor = id->data; | |
2647 | int portnr, ret; | |
2648 | ||
2649 | portnr = pl011_find_free_port(); | |
2650 | if (portnr < 0) | |
2651 | return portnr; | |
2652 | ||
2653 | uap = devm_kzalloc(&dev->dev, sizeof(struct uart_amba_port), | |
2654 | GFP_KERNEL); | |
2655 | if (!uap) | |
2656 | return -ENOMEM; | |
2657 | ||
2658 | uap->clk = devm_clk_get(&dev->dev, NULL); | |
2659 | if (IS_ERR(uap->clk)) | |
2660 | return PTR_ERR(uap->clk); | |
2661 | ||
439403bd | 2662 | uap->reg_offset = vendor->reg_offset; |
3873e2d7 | 2663 | uap->vendor = vendor; |
3873e2d7 | 2664 | uap->fifosize = vendor->get_fifosize(dev); |
3b78fae7 | 2665 | uap->port.iotype = vendor->access_32b ? UPIO_MEM32 : UPIO_MEM; |
3873e2d7 AP |
2666 | uap->port.irq = dev->irq[0]; |
2667 | uap->port.ops = &amba_pl011_pops; | |
2668 | ||
2669 | snprintf(uap->type, sizeof(uap->type), "PL011 rev%u", amba_rev(dev)); | |
2670 | ||
2671 | ret = pl011_setup_port(&dev->dev, uap, &dev->res, portnr); | |
2672 | if (ret) | |
2673 | return ret; | |
2674 | ||
2675 | amba_set_drvdata(dev, uap); | |
2676 | ||
2677 | return pl011_register_port(uap); | |
2678 | } | |
2679 | ||
3fd269e7 | 2680 | static void pl011_remove(struct amba_device *dev) |
1da177e4 LT |
2681 | { |
2682 | struct uart_amba_port *uap = amba_get_drvdata(dev); | |
1da177e4 | 2683 | |
1da177e4 | 2684 | uart_remove_one_port(&amba_reg, &uap->port); |
49bb3c86 | 2685 | pl011_unregister_port(uap); |
1da177e4 LT |
2686 | } |
2687 | ||
d0ce850d UH |
2688 | #ifdef CONFIG_PM_SLEEP |
2689 | static int pl011_suspend(struct device *dev) | |
b736b89f | 2690 | { |
d0ce850d | 2691 | struct uart_amba_port *uap = dev_get_drvdata(dev); |
b736b89f LC |
2692 | |
2693 | if (!uap) | |
2694 | return -EINVAL; | |
2695 | ||
2696 | return uart_suspend_port(&amba_reg, &uap->port); | |
2697 | } | |
2698 | ||
d0ce850d | 2699 | static int pl011_resume(struct device *dev) |
b736b89f | 2700 | { |
d0ce850d | 2701 | struct uart_amba_port *uap = dev_get_drvdata(dev); |
b736b89f LC |
2702 | |
2703 | if (!uap) | |
2704 | return -EINVAL; | |
2705 | ||
2706 | return uart_resume_port(&amba_reg, &uap->port); | |
2707 | } | |
2708 | #endif | |
2709 | ||
d0ce850d UH |
2710 | static SIMPLE_DEV_PM_OPS(pl011_dev_pm_ops, pl011_suspend, pl011_resume); |
2711 | ||
0dd1e247 AP |
2712 | static int sbsa_uart_probe(struct platform_device *pdev) |
2713 | { | |
2714 | struct uart_amba_port *uap; | |
2715 | struct resource *r; | |
2716 | int portnr, ret; | |
2717 | int baudrate; | |
2718 | ||
2719 | /* | |
2720 | * Check the mandatory baud rate parameter in the DT node early | |
2721 | * so that we can easily exit with the error. | |
2722 | */ | |
2723 | if (pdev->dev.of_node) { | |
2724 | struct device_node *np = pdev->dev.of_node; | |
2725 | ||
2726 | ret = of_property_read_u32(np, "current-speed", &baudrate); | |
2727 | if (ret) | |
2728 | return ret; | |
2729 | } else { | |
2730 | baudrate = 115200; | |
2731 | } | |
2732 | ||
2733 | portnr = pl011_find_free_port(); | |
2734 | if (portnr < 0) | |
2735 | return portnr; | |
2736 | ||
2737 | uap = devm_kzalloc(&pdev->dev, sizeof(struct uart_amba_port), | |
2738 | GFP_KERNEL); | |
2739 | if (!uap) | |
2740 | return -ENOMEM; | |
2741 | ||
394a9e2c | 2742 | ret = platform_get_irq(pdev, 0); |
1df21786 | 2743 | if (ret < 0) |
394a9e2c | 2744 | return ret; |
394a9e2c JS |
2745 | uap->port.irq = ret; |
2746 | ||
37ef38f3 TT |
2747 | #ifdef CONFIG_ACPI_SPCR_TABLE |
2748 | if (qdf2400_e44_present) { | |
2749 | dev_info(&pdev->dev, "working around QDF2400 SoC erratum 44\n"); | |
2750 | uap->vendor = &vendor_qdt_qdf2400_e44; | |
2751 | } else | |
2752 | #endif | |
2753 | uap->vendor = &vendor_sbsa; | |
2754 | ||
2755 | uap->reg_offset = uap->vendor->reg_offset; | |
0dd1e247 | 2756 | uap->fifosize = 32; |
37ef38f3 | 2757 | uap->port.iotype = uap->vendor->access_32b ? UPIO_MEM32 : UPIO_MEM; |
0dd1e247 AP |
2758 | uap->port.ops = &sbsa_uart_pops; |
2759 | uap->fixed_baud = baudrate; | |
2760 | ||
2761 | snprintf(uap->type, sizeof(uap->type), "SBSA"); | |
2762 | ||
2763 | r = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
2764 | ||
2765 | ret = pl011_setup_port(&pdev->dev, uap, r, portnr); | |
2766 | if (ret) | |
2767 | return ret; | |
2768 | ||
2769 | platform_set_drvdata(pdev, uap); | |
2770 | ||
2771 | return pl011_register_port(uap); | |
2772 | } | |
2773 | ||
2774 | static int sbsa_uart_remove(struct platform_device *pdev) | |
2775 | { | |
2776 | struct uart_amba_port *uap = platform_get_drvdata(pdev); | |
2777 | ||
2778 | uart_remove_one_port(&amba_reg, &uap->port); | |
2779 | pl011_unregister_port(uap); | |
2780 | return 0; | |
2781 | } | |
2782 | ||
2783 | static const struct of_device_id sbsa_uart_of_match[] = { | |
2784 | { .compatible = "arm,sbsa-uart", }, | |
2785 | {}, | |
2786 | }; | |
2787 | MODULE_DEVICE_TABLE(of, sbsa_uart_of_match); | |
2788 | ||
7789c1f1 | 2789 | static const struct acpi_device_id __maybe_unused sbsa_uart_acpi_match[] = { |
3db9ab0b GG |
2790 | { "ARMH0011", 0 }, |
2791 | {}, | |
2792 | }; | |
2793 | MODULE_DEVICE_TABLE(acpi, sbsa_uart_acpi_match); | |
2794 | ||
0dd1e247 AP |
2795 | static struct platform_driver arm_sbsa_uart_platform_driver = { |
2796 | .probe = sbsa_uart_probe, | |
2797 | .remove = sbsa_uart_remove, | |
2798 | .driver = { | |
2799 | .name = "sbsa-uart", | |
2301ec36 | 2800 | .pm = &pl011_dev_pm_ops, |
0dd1e247 | 2801 | .of_match_table = of_match_ptr(sbsa_uart_of_match), |
3db9ab0b | 2802 | .acpi_match_table = ACPI_PTR(sbsa_uart_acpi_match), |
64609794 | 2803 | .suppress_bind_attrs = IS_BUILTIN(CONFIG_SERIAL_AMBA_PL011), |
0dd1e247 AP |
2804 | }, |
2805 | }; | |
2806 | ||
a704ddc2 | 2807 | static const struct amba_id pl011_ids[] = { |
1da177e4 LT |
2808 | { |
2809 | .id = 0x00041011, | |
2810 | .mask = 0x000fffff, | |
5926a295 AR |
2811 | .data = &vendor_arm, |
2812 | }, | |
2813 | { | |
2814 | .id = 0x00380802, | |
2815 | .mask = 0x00ffffff, | |
2816 | .data = &vendor_st, | |
1da177e4 | 2817 | }, |
2426fbc7 SG |
2818 | { |
2819 | .id = AMBA_LINUX_ID(0x00, 0x1, 0xffe), | |
2820 | .mask = 0x00ffffff, | |
2821 | .data = &vendor_zte, | |
2822 | }, | |
1da177e4 LT |
2823 | { 0, 0 }, |
2824 | }; | |
2825 | ||
60f7a33b DM |
2826 | MODULE_DEVICE_TABLE(amba, pl011_ids); |
2827 | ||
1da177e4 LT |
2828 | static struct amba_driver pl011_driver = { |
2829 | .drv = { | |
2830 | .name = "uart-pl011", | |
d0ce850d | 2831 | .pm = &pl011_dev_pm_ops, |
64609794 | 2832 | .suppress_bind_attrs = IS_BUILTIN(CONFIG_SERIAL_AMBA_PL011), |
1da177e4 LT |
2833 | }, |
2834 | .id_table = pl011_ids, | |
2835 | .probe = pl011_probe, | |
2836 | .remove = pl011_remove, | |
2837 | }; | |
2838 | ||
2839 | static int __init pl011_init(void) | |
2840 | { | |
1da177e4 LT |
2841 | printk(KERN_INFO "Serial: AMBA PL011 UART driver\n"); |
2842 | ||
0dd1e247 AP |
2843 | if (platform_driver_register(&arm_sbsa_uart_platform_driver)) |
2844 | pr_warn("could not register SBSA UART platform driver\n"); | |
062a68a5 | 2845 | return amba_driver_register(&pl011_driver); |
1da177e4 LT |
2846 | } |
2847 | ||
2848 | static void __exit pl011_exit(void) | |
2849 | { | |
0dd1e247 | 2850 | platform_driver_unregister(&arm_sbsa_uart_platform_driver); |
1da177e4 | 2851 | amba_driver_unregister(&pl011_driver); |
1da177e4 LT |
2852 | } |
2853 | ||
4dd9e742 AR |
2854 | /* |
2855 | * While this can be a module, if builtin it's most likely the console | |
2856 | * So let's leave module_exit but move module_init to an earlier place | |
2857 | */ | |
2858 | arch_initcall(pl011_init); | |
1da177e4 LT |
2859 | module_exit(pl011_exit); |
2860 | ||
2861 | MODULE_AUTHOR("ARM Ltd/Deep Blue Solutions Ltd"); | |
2862 | MODULE_DESCRIPTION("ARM AMBA serial port driver"); | |
2863 | MODULE_LICENSE("GPL"); |