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2874c5fd | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
5fa29a17 MW |
2 | /* |
3 | * Driver for the Cirrus Logic EP93xx DMA Controller | |
4 | * | |
5 | * Copyright (C) 2011 Mika Westerberg | |
6 | * | |
7 | * DMA M2P implementation is based on the original | |
8 | * arch/arm/mach-ep93xx/dma-m2p.c which has following copyrights: | |
9 | * | |
10 | * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org> | |
11 | * Copyright (C) 2006 Applied Data Systems | |
12 | * Copyright (C) 2009 Ryan Mallon <rmallon@gmail.com> | |
13 | * | |
14 | * This driver is based on dw_dmac and amba-pl08x drivers. | |
5fa29a17 MW |
15 | */ |
16 | ||
17 | #include <linux/clk.h> | |
18 | #include <linux/init.h> | |
19 | #include <linux/interrupt.h> | |
20 | #include <linux/dmaengine.h> | |
2389d674 | 21 | #include <linux/module.h> |
ac316725 | 22 | #include <linux/mod_devicetable.h> |
5fa29a17 MW |
23 | #include <linux/platform_device.h> |
24 | #include <linux/slab.h> | |
25 | ||
a3b29245 | 26 | #include <linux/platform_data/dma-ep93xx.h> |
5fa29a17 | 27 | |
d2ebfb33 RKAL |
28 | #include "dmaengine.h" |
29 | ||
5fa29a17 MW |
30 | /* M2P registers */ |
31 | #define M2P_CONTROL 0x0000 | |
32 | #define M2P_CONTROL_STALLINT BIT(0) | |
33 | #define M2P_CONTROL_NFBINT BIT(1) | |
34 | #define M2P_CONTROL_CH_ERROR_INT BIT(3) | |
35 | #define M2P_CONTROL_ENABLE BIT(4) | |
36 | #define M2P_CONTROL_ICE BIT(6) | |
37 | ||
38 | #define M2P_INTERRUPT 0x0004 | |
39 | #define M2P_INTERRUPT_STALL BIT(0) | |
40 | #define M2P_INTERRUPT_NFB BIT(1) | |
41 | #define M2P_INTERRUPT_ERROR BIT(3) | |
42 | ||
43 | #define M2P_PPALLOC 0x0008 | |
44 | #define M2P_STATUS 0x000c | |
45 | ||
46 | #define M2P_MAXCNT0 0x0020 | |
47 | #define M2P_BASE0 0x0024 | |
48 | #define M2P_MAXCNT1 0x0030 | |
49 | #define M2P_BASE1 0x0034 | |
50 | ||
51 | #define M2P_STATE_IDLE 0 | |
52 | #define M2P_STATE_STALL 1 | |
53 | #define M2P_STATE_ON 2 | |
54 | #define M2P_STATE_NEXT 3 | |
55 | ||
56 | /* M2M registers */ | |
57 | #define M2M_CONTROL 0x0000 | |
58 | #define M2M_CONTROL_DONEINT BIT(2) | |
59 | #define M2M_CONTROL_ENABLE BIT(3) | |
60 | #define M2M_CONTROL_START BIT(4) | |
61 | #define M2M_CONTROL_DAH BIT(11) | |
62 | #define M2M_CONTROL_SAH BIT(12) | |
63 | #define M2M_CONTROL_PW_SHIFT 9 | |
64 | #define M2M_CONTROL_PW_8 (0 << M2M_CONTROL_PW_SHIFT) | |
65 | #define M2M_CONTROL_PW_16 (1 << M2M_CONTROL_PW_SHIFT) | |
66 | #define M2M_CONTROL_PW_32 (2 << M2M_CONTROL_PW_SHIFT) | |
67 | #define M2M_CONTROL_PW_MASK (3 << M2M_CONTROL_PW_SHIFT) | |
68 | #define M2M_CONTROL_TM_SHIFT 13 | |
69 | #define M2M_CONTROL_TM_TX (1 << M2M_CONTROL_TM_SHIFT) | |
70 | #define M2M_CONTROL_TM_RX (2 << M2M_CONTROL_TM_SHIFT) | |
2b3c83ef | 71 | #define M2M_CONTROL_NFBINT BIT(21) |
5fa29a17 MW |
72 | #define M2M_CONTROL_RSS_SHIFT 22 |
73 | #define M2M_CONTROL_RSS_SSPRX (1 << M2M_CONTROL_RSS_SHIFT) | |
74 | #define M2M_CONTROL_RSS_SSPTX (2 << M2M_CONTROL_RSS_SHIFT) | |
75 | #define M2M_CONTROL_RSS_IDE (3 << M2M_CONTROL_RSS_SHIFT) | |
76 | #define M2M_CONTROL_NO_HDSK BIT(24) | |
77 | #define M2M_CONTROL_PWSC_SHIFT 25 | |
78 | ||
79 | #define M2M_INTERRUPT 0x0004 | |
2b3c83ef RP |
80 | #define M2M_INTERRUPT_MASK 6 |
81 | ||
82 | #define M2M_STATUS 0x000c | |
83 | #define M2M_STATUS_CTL_SHIFT 1 | |
84 | #define M2M_STATUS_CTL_IDLE (0 << M2M_STATUS_CTL_SHIFT) | |
85 | #define M2M_STATUS_CTL_STALL (1 << M2M_STATUS_CTL_SHIFT) | |
86 | #define M2M_STATUS_CTL_MEMRD (2 << M2M_STATUS_CTL_SHIFT) | |
87 | #define M2M_STATUS_CTL_MEMWR (3 << M2M_STATUS_CTL_SHIFT) | |
88 | #define M2M_STATUS_CTL_BWCWAIT (4 << M2M_STATUS_CTL_SHIFT) | |
89 | #define M2M_STATUS_CTL_MASK (7 << M2M_STATUS_CTL_SHIFT) | |
90 | #define M2M_STATUS_BUF_SHIFT 4 | |
91 | #define M2M_STATUS_BUF_NO (0 << M2M_STATUS_BUF_SHIFT) | |
92 | #define M2M_STATUS_BUF_ON (1 << M2M_STATUS_BUF_SHIFT) | |
93 | #define M2M_STATUS_BUF_NEXT (2 << M2M_STATUS_BUF_SHIFT) | |
94 | #define M2M_STATUS_BUF_MASK (3 << M2M_STATUS_BUF_SHIFT) | |
95 | #define M2M_STATUS_DONE BIT(6) | |
5fa29a17 MW |
96 | |
97 | #define M2M_BCR0 0x0010 | |
98 | #define M2M_BCR1 0x0014 | |
99 | #define M2M_SAR_BASE0 0x0018 | |
100 | #define M2M_SAR_BASE1 0x001c | |
101 | #define M2M_DAR_BASE0 0x002c | |
102 | #define M2M_DAR_BASE1 0x0030 | |
103 | ||
104 | #define DMA_MAX_CHAN_BYTES 0xffff | |
105 | #define DMA_MAX_CHAN_DESCRIPTORS 32 | |
106 | ||
107 | struct ep93xx_dma_engine; | |
4e3c4040 VK |
108 | static int ep93xx_dma_slave_config_write(struct dma_chan *chan, |
109 | enum dma_transfer_direction dir, | |
110 | struct dma_slave_config *config); | |
5fa29a17 MW |
111 | |
112 | /** | |
113 | * struct ep93xx_dma_desc - EP93xx specific transaction descriptor | |
114 | * @src_addr: source address of the transaction | |
115 | * @dst_addr: destination address of the transaction | |
116 | * @size: size of the transaction (in bytes) | |
117 | * @complete: this descriptor is completed | |
118 | * @txd: dmaengine API descriptor | |
119 | * @tx_list: list of linked descriptors | |
120 | * @node: link used for putting this into a channel queue | |
121 | */ | |
122 | struct ep93xx_dma_desc { | |
123 | u32 src_addr; | |
124 | u32 dst_addr; | |
125 | size_t size; | |
126 | bool complete; | |
127 | struct dma_async_tx_descriptor txd; | |
128 | struct list_head tx_list; | |
129 | struct list_head node; | |
130 | }; | |
131 | ||
132 | /** | |
133 | * struct ep93xx_dma_chan - an EP93xx DMA M2P/M2M channel | |
134 | * @chan: dmaengine API channel | |
135 | * @edma: pointer to to the engine device | |
136 | * @regs: memory mapped registers | |
137 | * @irq: interrupt number of the channel | |
138 | * @clk: clock used by this channel | |
139 | * @tasklet: channel specific tasklet used for callbacks | |
140 | * @lock: lock protecting the fields following | |
141 | * @flags: flags for the channel | |
142 | * @buffer: which buffer to use next (0/1) | |
5fa29a17 MW |
143 | * @active: flattened chain of descriptors currently being processed |
144 | * @queue: pending descriptors which are handled next | |
145 | * @free_list: list of free descriptors which can be used | |
146 | * @runtime_addr: physical address currently used as dest/src (M2M only). This | |
b2be07d0 | 147 | * is set via .device_config before slave operation is |
5fa29a17 MW |
148 | * prepared |
149 | * @runtime_ctrl: M2M runtime values for the control register. | |
150 | * | |
151 | * As EP93xx DMA controller doesn't support real chained DMA descriptors we | |
152 | * will have slightly different scheme here: @active points to a head of | |
153 | * flattened DMA descriptor chain. | |
154 | * | |
155 | * @queue holds pending transactions. These are linked through the first | |
156 | * descriptor in the chain. When a descriptor is moved to the @active queue, | |
157 | * the first and chained descriptors are flattened into a single list. | |
158 | * | |
159 | * @chan.private holds pointer to &struct ep93xx_dma_data which contains | |
160 | * necessary channel configuration information. For memcpy channels this must | |
161 | * be %NULL. | |
162 | */ | |
163 | struct ep93xx_dma_chan { | |
164 | struct dma_chan chan; | |
165 | const struct ep93xx_dma_engine *edma; | |
166 | void __iomem *regs; | |
167 | int irq; | |
168 | struct clk *clk; | |
169 | struct tasklet_struct tasklet; | |
170 | /* protects the fields following */ | |
171 | spinlock_t lock; | |
172 | unsigned long flags; | |
173 | /* Channel is configured for cyclic transfers */ | |
174 | #define EP93XX_DMA_IS_CYCLIC 0 | |
175 | ||
176 | int buffer; | |
5fa29a17 MW |
177 | struct list_head active; |
178 | struct list_head queue; | |
179 | struct list_head free_list; | |
180 | u32 runtime_addr; | |
181 | u32 runtime_ctrl; | |
4e3c4040 | 182 | struct dma_slave_config slave_config; |
5fa29a17 MW |
183 | }; |
184 | ||
185 | /** | |
186 | * struct ep93xx_dma_engine - the EP93xx DMA engine instance | |
187 | * @dma_dev: holds the dmaengine device | |
188 | * @m2m: is this an M2M or M2P device | |
189 | * @hw_setup: method which sets the channel up for operation | |
190 | * @hw_shutdown: shuts the channel down and flushes whatever is left | |
191 | * @hw_submit: pushes active descriptor(s) to the hardware | |
192 | * @hw_interrupt: handle the interrupt | |
193 | * @num_channels: number of channels for this instance | |
194 | * @channels: array of channels | |
195 | * | |
196 | * There is one instance of this struct for the M2P channels and one for the | |
197 | * M2M channels. hw_xxx() methods are used to perform operations which are | |
198 | * different on M2M and M2P channels. These methods are called with channel | |
199 | * lock held and interrupts disabled so they cannot sleep. | |
200 | */ | |
201 | struct ep93xx_dma_engine { | |
202 | struct dma_device dma_dev; | |
203 | bool m2m; | |
204 | int (*hw_setup)(struct ep93xx_dma_chan *); | |
98f9de36 | 205 | void (*hw_synchronize)(struct ep93xx_dma_chan *); |
5fa29a17 MW |
206 | void (*hw_shutdown)(struct ep93xx_dma_chan *); |
207 | void (*hw_submit)(struct ep93xx_dma_chan *); | |
208 | int (*hw_interrupt)(struct ep93xx_dma_chan *); | |
209 | #define INTERRUPT_UNKNOWN 0 | |
210 | #define INTERRUPT_DONE 1 | |
211 | #define INTERRUPT_NEXT_BUFFER 2 | |
212 | ||
213 | size_t num_channels; | |
214 | struct ep93xx_dma_chan channels[]; | |
215 | }; | |
216 | ||
217 | static inline struct device *chan2dev(struct ep93xx_dma_chan *edmac) | |
218 | { | |
219 | return &edmac->chan.dev->device; | |
220 | } | |
221 | ||
222 | static struct ep93xx_dma_chan *to_ep93xx_dma_chan(struct dma_chan *chan) | |
223 | { | |
224 | return container_of(chan, struct ep93xx_dma_chan, chan); | |
225 | } | |
226 | ||
227 | /** | |
228 | * ep93xx_dma_set_active - set new active descriptor chain | |
229 | * @edmac: channel | |
230 | * @desc: head of the new active descriptor chain | |
231 | * | |
232 | * Sets @desc to be the head of the new active descriptor chain. This is the | |
233 | * chain which is processed next. The active list must be empty before calling | |
234 | * this function. | |
235 | * | |
236 | * Called with @edmac->lock held and interrupts disabled. | |
237 | */ | |
238 | static void ep93xx_dma_set_active(struct ep93xx_dma_chan *edmac, | |
239 | struct ep93xx_dma_desc *desc) | |
240 | { | |
241 | BUG_ON(!list_empty(&edmac->active)); | |
242 | ||
243 | list_add_tail(&desc->node, &edmac->active); | |
244 | ||
245 | /* Flatten the @desc->tx_list chain into @edmac->active list */ | |
246 | while (!list_empty(&desc->tx_list)) { | |
247 | struct ep93xx_dma_desc *d = list_first_entry(&desc->tx_list, | |
248 | struct ep93xx_dma_desc, node); | |
249 | ||
250 | /* | |
251 | * We copy the callback parameters from the first descriptor | |
252 | * to all the chained descriptors. This way we can call the | |
253 | * callback without having to find out the first descriptor in | |
254 | * the chain. Useful for cyclic transfers. | |
255 | */ | |
256 | d->txd.callback = desc->txd.callback; | |
257 | d->txd.callback_param = desc->txd.callback_param; | |
258 | ||
259 | list_move_tail(&d->node, &edmac->active); | |
260 | } | |
261 | } | |
262 | ||
263 | /* Called with @edmac->lock held and interrupts disabled */ | |
264 | static struct ep93xx_dma_desc * | |
265 | ep93xx_dma_get_active(struct ep93xx_dma_chan *edmac) | |
266 | { | |
360af35b MY |
267 | return list_first_entry_or_null(&edmac->active, |
268 | struct ep93xx_dma_desc, node); | |
5fa29a17 MW |
269 | } |
270 | ||
271 | /** | |
272 | * ep93xx_dma_advance_active - advances to the next active descriptor | |
273 | * @edmac: channel | |
274 | * | |
275 | * Function advances active descriptor to the next in the @edmac->active and | |
276 | * returns %true if we still have descriptors in the chain to process. | |
277 | * Otherwise returns %false. | |
278 | * | |
279 | * When the channel is in cyclic mode always returns %true. | |
280 | * | |
281 | * Called with @edmac->lock held and interrupts disabled. | |
282 | */ | |
283 | static bool ep93xx_dma_advance_active(struct ep93xx_dma_chan *edmac) | |
284 | { | |
6d0709d2 MW |
285 | struct ep93xx_dma_desc *desc; |
286 | ||
5fa29a17 MW |
287 | list_rotate_left(&edmac->active); |
288 | ||
289 | if (test_bit(EP93XX_DMA_IS_CYCLIC, &edmac->flags)) | |
290 | return true; | |
291 | ||
6d0709d2 MW |
292 | desc = ep93xx_dma_get_active(edmac); |
293 | if (!desc) | |
294 | return false; | |
295 | ||
5fa29a17 MW |
296 | /* |
297 | * If txd.cookie is set it means that we are back in the first | |
298 | * descriptor in the chain and hence done with it. | |
299 | */ | |
6d0709d2 | 300 | return !desc->txd.cookie; |
5fa29a17 MW |
301 | } |
302 | ||
303 | /* | |
304 | * M2P DMA implementation | |
305 | */ | |
306 | ||
307 | static void m2p_set_control(struct ep93xx_dma_chan *edmac, u32 control) | |
308 | { | |
309 | writel(control, edmac->regs + M2P_CONTROL); | |
310 | /* | |
311 | * EP93xx User's Guide states that we must perform a dummy read after | |
312 | * write to the control register. | |
313 | */ | |
314 | readl(edmac->regs + M2P_CONTROL); | |
315 | } | |
316 | ||
317 | static int m2p_hw_setup(struct ep93xx_dma_chan *edmac) | |
318 | { | |
319 | struct ep93xx_dma_data *data = edmac->chan.private; | |
320 | u32 control; | |
321 | ||
322 | writel(data->port & 0xf, edmac->regs + M2P_PPALLOC); | |
323 | ||
324 | control = M2P_CONTROL_CH_ERROR_INT | M2P_CONTROL_ICE | |
325 | | M2P_CONTROL_ENABLE; | |
326 | m2p_set_control(edmac, control); | |
327 | ||
0037ae47 AS |
328 | edmac->buffer = 0; |
329 | ||
5fa29a17 MW |
330 | return 0; |
331 | } | |
332 | ||
333 | static inline u32 m2p_channel_state(struct ep93xx_dma_chan *edmac) | |
334 | { | |
335 | return (readl(edmac->regs + M2P_STATUS) >> 4) & 0x3; | |
336 | } | |
337 | ||
98f9de36 | 338 | static void m2p_hw_synchronize(struct ep93xx_dma_chan *edmac) |
5fa29a17 | 339 | { |
98f9de36 | 340 | unsigned long flags; |
5fa29a17 MW |
341 | u32 control; |
342 | ||
98f9de36 | 343 | spin_lock_irqsave(&edmac->lock, flags); |
5fa29a17 MW |
344 | control = readl(edmac->regs + M2P_CONTROL); |
345 | control &= ~(M2P_CONTROL_STALLINT | M2P_CONTROL_NFBINT); | |
346 | m2p_set_control(edmac, control); | |
98f9de36 | 347 | spin_unlock_irqrestore(&edmac->lock, flags); |
5fa29a17 MW |
348 | |
349 | while (m2p_channel_state(edmac) >= M2P_STATE_ON) | |
98f9de36 AS |
350 | schedule(); |
351 | } | |
5fa29a17 | 352 | |
98f9de36 AS |
353 | static void m2p_hw_shutdown(struct ep93xx_dma_chan *edmac) |
354 | { | |
5fa29a17 MW |
355 | m2p_set_control(edmac, 0); |
356 | ||
98f9de36 AS |
357 | while (m2p_channel_state(edmac) != M2P_STATE_IDLE) |
358 | dev_warn(chan2dev(edmac), "M2P: Not yet IDLE\n"); | |
5fa29a17 MW |
359 | } |
360 | ||
361 | static void m2p_fill_desc(struct ep93xx_dma_chan *edmac) | |
362 | { | |
6d0709d2 | 363 | struct ep93xx_dma_desc *desc; |
5fa29a17 MW |
364 | u32 bus_addr; |
365 | ||
6d0709d2 MW |
366 | desc = ep93xx_dma_get_active(edmac); |
367 | if (!desc) { | |
368 | dev_warn(chan2dev(edmac), "M2P: empty descriptor list\n"); | |
369 | return; | |
370 | } | |
371 | ||
db8196df | 372 | if (ep93xx_dma_chan_direction(&edmac->chan) == DMA_MEM_TO_DEV) |
5fa29a17 MW |
373 | bus_addr = desc->src_addr; |
374 | else | |
375 | bus_addr = desc->dst_addr; | |
376 | ||
377 | if (edmac->buffer == 0) { | |
378 | writel(desc->size, edmac->regs + M2P_MAXCNT0); | |
379 | writel(bus_addr, edmac->regs + M2P_BASE0); | |
380 | } else { | |
381 | writel(desc->size, edmac->regs + M2P_MAXCNT1); | |
382 | writel(bus_addr, edmac->regs + M2P_BASE1); | |
383 | } | |
384 | ||
385 | edmac->buffer ^= 1; | |
386 | } | |
387 | ||
388 | static void m2p_hw_submit(struct ep93xx_dma_chan *edmac) | |
389 | { | |
390 | u32 control = readl(edmac->regs + M2P_CONTROL); | |
391 | ||
392 | m2p_fill_desc(edmac); | |
393 | control |= M2P_CONTROL_STALLINT; | |
394 | ||
395 | if (ep93xx_dma_advance_active(edmac)) { | |
396 | m2p_fill_desc(edmac); | |
397 | control |= M2P_CONTROL_NFBINT; | |
398 | } | |
399 | ||
400 | m2p_set_control(edmac, control); | |
401 | } | |
402 | ||
403 | static int m2p_hw_interrupt(struct ep93xx_dma_chan *edmac) | |
404 | { | |
405 | u32 irq_status = readl(edmac->regs + M2P_INTERRUPT); | |
406 | u32 control; | |
407 | ||
408 | if (irq_status & M2P_INTERRUPT_ERROR) { | |
409 | struct ep93xx_dma_desc *desc = ep93xx_dma_get_active(edmac); | |
410 | ||
411 | /* Clear the error interrupt */ | |
412 | writel(1, edmac->regs + M2P_INTERRUPT); | |
413 | ||
414 | /* | |
415 | * It seems that there is no easy way of reporting errors back | |
416 | * to client so we just report the error here and continue as | |
417 | * usual. | |
418 | * | |
419 | * Revisit this when there is a mechanism to report back the | |
420 | * errors. | |
421 | */ | |
422 | dev_err(chan2dev(edmac), | |
423 | "DMA transfer failed! Details:\n" | |
424 | "\tcookie : %d\n" | |
425 | "\tsrc_addr : 0x%08x\n" | |
426 | "\tdst_addr : 0x%08x\n" | |
427 | "\tsize : %zu\n", | |
428 | desc->txd.cookie, desc->src_addr, desc->dst_addr, | |
429 | desc->size); | |
430 | } | |
431 | ||
94901e1b AS |
432 | /* |
433 | * Even latest E2 silicon revision sometimes assert STALL interrupt | |
434 | * instead of NFB. Therefore we treat them equally, basing on the | |
435 | * amount of data we still have to transfer. | |
436 | */ | |
437 | if (!(irq_status & (M2P_INTERRUPT_STALL | M2P_INTERRUPT_NFB))) | |
438 | return INTERRUPT_UNKNOWN; | |
5fa29a17 | 439 | |
94901e1b AS |
440 | if (ep93xx_dma_advance_active(edmac)) { |
441 | m2p_fill_desc(edmac); | |
5fa29a17 MW |
442 | return INTERRUPT_NEXT_BUFFER; |
443 | } | |
444 | ||
94901e1b AS |
445 | /* Disable interrupts */ |
446 | control = readl(edmac->regs + M2P_CONTROL); | |
447 | control &= ~(M2P_CONTROL_STALLINT | M2P_CONTROL_NFBINT); | |
448 | m2p_set_control(edmac, control); | |
449 | ||
450 | return INTERRUPT_DONE; | |
5fa29a17 MW |
451 | } |
452 | ||
453 | /* | |
454 | * M2M DMA implementation | |
5fa29a17 MW |
455 | */ |
456 | ||
457 | static int m2m_hw_setup(struct ep93xx_dma_chan *edmac) | |
458 | { | |
459 | const struct ep93xx_dma_data *data = edmac->chan.private; | |
460 | u32 control = 0; | |
461 | ||
462 | if (!data) { | |
463 | /* This is memcpy channel, nothing to configure */ | |
464 | writel(control, edmac->regs + M2M_CONTROL); | |
465 | return 0; | |
466 | } | |
467 | ||
468 | switch (data->port) { | |
469 | case EP93XX_DMA_SSP: | |
470 | /* | |
471 | * This was found via experimenting - anything less than 5 | |
472 | * causes the channel to perform only a partial transfer which | |
473 | * leads to problems since we don't get DONE interrupt then. | |
474 | */ | |
475 | control = (5 << M2M_CONTROL_PWSC_SHIFT); | |
476 | control |= M2M_CONTROL_NO_HDSK; | |
477 | ||
db8196df | 478 | if (data->direction == DMA_MEM_TO_DEV) { |
5fa29a17 MW |
479 | control |= M2M_CONTROL_DAH; |
480 | control |= M2M_CONTROL_TM_TX; | |
481 | control |= M2M_CONTROL_RSS_SSPTX; | |
482 | } else { | |
483 | control |= M2M_CONTROL_SAH; | |
484 | control |= M2M_CONTROL_TM_RX; | |
485 | control |= M2M_CONTROL_RSS_SSPRX; | |
486 | } | |
487 | break; | |
488 | ||
489 | case EP93XX_DMA_IDE: | |
490 | /* | |
491 | * This IDE part is totally untested. Values below are taken | |
492 | * from the EP93xx Users's Guide and might not be correct. | |
493 | */ | |
db8196df | 494 | if (data->direction == DMA_MEM_TO_DEV) { |
5fa29a17 MW |
495 | /* Worst case from the UG */ |
496 | control = (3 << M2M_CONTROL_PWSC_SHIFT); | |
497 | control |= M2M_CONTROL_DAH; | |
498 | control |= M2M_CONTROL_TM_TX; | |
499 | } else { | |
500 | control = (2 << M2M_CONTROL_PWSC_SHIFT); | |
501 | control |= M2M_CONTROL_SAH; | |
502 | control |= M2M_CONTROL_TM_RX; | |
503 | } | |
b62cfc5e RP |
504 | |
505 | control |= M2M_CONTROL_NO_HDSK; | |
506 | control |= M2M_CONTROL_RSS_IDE; | |
507 | control |= M2M_CONTROL_PW_16; | |
5fa29a17 MW |
508 | break; |
509 | ||
510 | default: | |
511 | return -EINVAL; | |
512 | } | |
513 | ||
514 | writel(control, edmac->regs + M2M_CONTROL); | |
515 | return 0; | |
516 | } | |
517 | ||
518 | static void m2m_hw_shutdown(struct ep93xx_dma_chan *edmac) | |
519 | { | |
520 | /* Just disable the channel */ | |
521 | writel(0, edmac->regs + M2M_CONTROL); | |
522 | } | |
523 | ||
524 | static void m2m_fill_desc(struct ep93xx_dma_chan *edmac) | |
525 | { | |
6d0709d2 MW |
526 | struct ep93xx_dma_desc *desc; |
527 | ||
528 | desc = ep93xx_dma_get_active(edmac); | |
529 | if (!desc) { | |
530 | dev_warn(chan2dev(edmac), "M2M: empty descriptor list\n"); | |
531 | return; | |
532 | } | |
5fa29a17 MW |
533 | |
534 | if (edmac->buffer == 0) { | |
535 | writel(desc->src_addr, edmac->regs + M2M_SAR_BASE0); | |
536 | writel(desc->dst_addr, edmac->regs + M2M_DAR_BASE0); | |
537 | writel(desc->size, edmac->regs + M2M_BCR0); | |
538 | } else { | |
539 | writel(desc->src_addr, edmac->regs + M2M_SAR_BASE1); | |
540 | writel(desc->dst_addr, edmac->regs + M2M_DAR_BASE1); | |
541 | writel(desc->size, edmac->regs + M2M_BCR1); | |
542 | } | |
543 | ||
544 | edmac->buffer ^= 1; | |
545 | } | |
546 | ||
547 | static void m2m_hw_submit(struct ep93xx_dma_chan *edmac) | |
548 | { | |
549 | struct ep93xx_dma_data *data = edmac->chan.private; | |
550 | u32 control = readl(edmac->regs + M2M_CONTROL); | |
551 | ||
552 | /* | |
553 | * Since we allow clients to configure PW (peripheral width) we always | |
554 | * clear PW bits here and then set them according what is given in | |
555 | * the runtime configuration. | |
556 | */ | |
557 | control &= ~M2M_CONTROL_PW_MASK; | |
558 | control |= edmac->runtime_ctrl; | |
559 | ||
560 | m2m_fill_desc(edmac); | |
561 | control |= M2M_CONTROL_DONEINT; | |
562 | ||
2b3c83ef RP |
563 | if (ep93xx_dma_advance_active(edmac)) { |
564 | m2m_fill_desc(edmac); | |
565 | control |= M2M_CONTROL_NFBINT; | |
566 | } | |
567 | ||
5fa29a17 MW |
568 | /* |
569 | * Now we can finally enable the channel. For M2M channel this must be | |
570 | * done _after_ the BCRx registers are programmed. | |
571 | */ | |
572 | control |= M2M_CONTROL_ENABLE; | |
573 | writel(control, edmac->regs + M2M_CONTROL); | |
574 | ||
575 | if (!data) { | |
576 | /* | |
577 | * For memcpy channels the software trigger must be asserted | |
578 | * in order to start the memcpy operation. | |
579 | */ | |
580 | control |= M2M_CONTROL_START; | |
581 | writel(control, edmac->regs + M2M_CONTROL); | |
582 | } | |
583 | } | |
584 | ||
2b3c83ef RP |
585 | /* |
586 | * According to EP93xx User's Guide, we should receive DONE interrupt when all | |
587 | * M2M DMA controller transactions complete normally. This is not always the | |
588 | * case - sometimes EP93xx M2M DMA asserts DONE interrupt when the DMA channel | |
589 | * is still running (channel Buffer FSM in DMA_BUF_ON state, and channel | |
590 | * Control FSM in DMA_MEM_RD state, observed at least in IDE-DMA operation). | |
591 | * In effect, disabling the channel when only DONE bit is set could stop | |
592 | * currently running DMA transfer. To avoid this, we use Buffer FSM and | |
593 | * Control FSM to check current state of DMA channel. | |
594 | */ | |
5fa29a17 MW |
595 | static int m2m_hw_interrupt(struct ep93xx_dma_chan *edmac) |
596 | { | |
2b3c83ef RP |
597 | u32 status = readl(edmac->regs + M2M_STATUS); |
598 | u32 ctl_fsm = status & M2M_STATUS_CTL_MASK; | |
599 | u32 buf_fsm = status & M2M_STATUS_BUF_MASK; | |
600 | bool done = status & M2M_STATUS_DONE; | |
601 | bool last_done; | |
5fa29a17 | 602 | u32 control; |
2b3c83ef | 603 | struct ep93xx_dma_desc *desc; |
5fa29a17 | 604 | |
2b3c83ef RP |
605 | /* Accept only DONE and NFB interrupts */ |
606 | if (!(readl(edmac->regs + M2M_INTERRUPT) & M2M_INTERRUPT_MASK)) | |
5fa29a17 MW |
607 | return INTERRUPT_UNKNOWN; |
608 | ||
2b3c83ef RP |
609 | if (done) { |
610 | /* Clear the DONE bit */ | |
611 | writel(0, edmac->regs + M2M_INTERRUPT); | |
612 | } | |
5fa29a17 | 613 | |
2b3c83ef RP |
614 | /* |
615 | * Check whether we are done with descriptors or not. This, together | |
616 | * with DMA channel state, determines action to take in interrupt. | |
617 | */ | |
618 | desc = ep93xx_dma_get_active(edmac); | |
619 | last_done = !desc || desc->txd.cookie; | |
5fa29a17 MW |
620 | |
621 | /* | |
2b3c83ef RP |
622 | * Use M2M DMA Buffer FSM and Control FSM to check current state of |
623 | * DMA channel. Using DONE and NFB bits from channel status register | |
624 | * or bits from channel interrupt register is not reliable. | |
5fa29a17 | 625 | */ |
2b3c83ef RP |
626 | if (!last_done && |
627 | (buf_fsm == M2M_STATUS_BUF_NO || | |
628 | buf_fsm == M2M_STATUS_BUF_ON)) { | |
629 | /* | |
630 | * Two buffers are ready for update when Buffer FSM is in | |
631 | * DMA_NO_BUF state. Only one buffer can be prepared without | |
632 | * disabling the channel or polling the DONE bit. | |
633 | * To simplify things, always prepare only one buffer. | |
634 | */ | |
635 | if (ep93xx_dma_advance_active(edmac)) { | |
636 | m2m_fill_desc(edmac); | |
637 | if (done && !edmac->chan.private) { | |
638 | /* Software trigger for memcpy channel */ | |
639 | control = readl(edmac->regs + M2M_CONTROL); | |
640 | control |= M2M_CONTROL_START; | |
641 | writel(control, edmac->regs + M2M_CONTROL); | |
642 | } | |
643 | return INTERRUPT_NEXT_BUFFER; | |
644 | } else { | |
645 | last_done = true; | |
646 | } | |
5fa29a17 MW |
647 | } |
648 | ||
2b3c83ef RP |
649 | /* |
650 | * Disable the channel only when Buffer FSM is in DMA_NO_BUF state | |
651 | * and Control FSM is in DMA_STALL state. | |
652 | */ | |
653 | if (last_done && | |
654 | buf_fsm == M2M_STATUS_BUF_NO && | |
655 | ctl_fsm == M2M_STATUS_CTL_STALL) { | |
656 | /* Disable interrupts and the channel */ | |
657 | control = readl(edmac->regs + M2M_CONTROL); | |
658 | control &= ~(M2M_CONTROL_DONEINT | M2M_CONTROL_NFBINT | |
659 | | M2M_CONTROL_ENABLE); | |
660 | writel(control, edmac->regs + M2M_CONTROL); | |
661 | return INTERRUPT_DONE; | |
662 | } | |
663 | ||
664 | /* | |
665 | * Nothing to do this time. | |
666 | */ | |
667 | return INTERRUPT_NEXT_BUFFER; | |
5fa29a17 MW |
668 | } |
669 | ||
670 | /* | |
671 | * DMA engine API implementation | |
672 | */ | |
673 | ||
674 | static struct ep93xx_dma_desc * | |
675 | ep93xx_dma_desc_get(struct ep93xx_dma_chan *edmac) | |
676 | { | |
677 | struct ep93xx_dma_desc *desc, *_desc; | |
678 | struct ep93xx_dma_desc *ret = NULL; | |
679 | unsigned long flags; | |
680 | ||
681 | spin_lock_irqsave(&edmac->lock, flags); | |
682 | list_for_each_entry_safe(desc, _desc, &edmac->free_list, node) { | |
683 | if (async_tx_test_ack(&desc->txd)) { | |
684 | list_del_init(&desc->node); | |
685 | ||
686 | /* Re-initialize the descriptor */ | |
687 | desc->src_addr = 0; | |
688 | desc->dst_addr = 0; | |
689 | desc->size = 0; | |
690 | desc->complete = false; | |
691 | desc->txd.cookie = 0; | |
692 | desc->txd.callback = NULL; | |
693 | desc->txd.callback_param = NULL; | |
694 | ||
695 | ret = desc; | |
696 | break; | |
697 | } | |
698 | } | |
699 | spin_unlock_irqrestore(&edmac->lock, flags); | |
700 | return ret; | |
701 | } | |
702 | ||
703 | static void ep93xx_dma_desc_put(struct ep93xx_dma_chan *edmac, | |
704 | struct ep93xx_dma_desc *desc) | |
705 | { | |
706 | if (desc) { | |
707 | unsigned long flags; | |
708 | ||
709 | spin_lock_irqsave(&edmac->lock, flags); | |
710 | list_splice_init(&desc->tx_list, &edmac->free_list); | |
711 | list_add(&desc->node, &edmac->free_list); | |
712 | spin_unlock_irqrestore(&edmac->lock, flags); | |
713 | } | |
714 | } | |
715 | ||
716 | /** | |
717 | * ep93xx_dma_advance_work - start processing the next pending transaction | |
718 | * @edmac: channel | |
719 | * | |
720 | * If we have pending transactions queued and we are currently idling, this | |
721 | * function takes the next queued transaction from the @edmac->queue and | |
722 | * pushes it to the hardware for execution. | |
723 | */ | |
724 | static void ep93xx_dma_advance_work(struct ep93xx_dma_chan *edmac) | |
725 | { | |
726 | struct ep93xx_dma_desc *new; | |
727 | unsigned long flags; | |
728 | ||
729 | spin_lock_irqsave(&edmac->lock, flags); | |
730 | if (!list_empty(&edmac->active) || list_empty(&edmac->queue)) { | |
731 | spin_unlock_irqrestore(&edmac->lock, flags); | |
732 | return; | |
733 | } | |
734 | ||
735 | /* Take the next descriptor from the pending queue */ | |
736 | new = list_first_entry(&edmac->queue, struct ep93xx_dma_desc, node); | |
737 | list_del_init(&new->node); | |
738 | ||
739 | ep93xx_dma_set_active(edmac, new); | |
740 | ||
741 | /* Push it to the hardware */ | |
742 | edmac->edma->hw_submit(edmac); | |
743 | spin_unlock_irqrestore(&edmac->lock, flags); | |
744 | } | |
745 | ||
5fa29a17 MW |
746 | static void ep93xx_dma_tasklet(unsigned long data) |
747 | { | |
748 | struct ep93xx_dma_chan *edmac = (struct ep93xx_dma_chan *)data; | |
749 | struct ep93xx_dma_desc *desc, *d; | |
dac86a14 | 750 | struct dmaengine_desc_callback cb; |
5fa29a17 MW |
751 | LIST_HEAD(list); |
752 | ||
dac86a14 | 753 | memset(&cb, 0, sizeof(cb)); |
5fa29a17 | 754 | spin_lock_irq(&edmac->lock); |
6d0709d2 MW |
755 | /* |
756 | * If dma_terminate_all() was called before we get to run, the active | |
757 | * list has become empty. If that happens we aren't supposed to do | |
758 | * anything more than call ep93xx_dma_advance_work(). | |
759 | */ | |
5fa29a17 | 760 | desc = ep93xx_dma_get_active(edmac); |
6d0709d2 MW |
761 | if (desc) { |
762 | if (desc->complete) { | |
d4116052 VK |
763 | /* mark descriptor complete for non cyclic case only */ |
764 | if (!test_bit(EP93XX_DMA_IS_CYCLIC, &edmac->flags)) | |
765 | dma_cookie_complete(&desc->txd); | |
6d0709d2 MW |
766 | list_splice_init(&edmac->active, &list); |
767 | } | |
dac86a14 | 768 | dmaengine_desc_get_callback(&desc->txd, &cb); |
5fa29a17 MW |
769 | } |
770 | spin_unlock_irq(&edmac->lock); | |
771 | ||
772 | /* Pick up the next descriptor from the queue */ | |
773 | ep93xx_dma_advance_work(edmac); | |
774 | ||
5fa29a17 MW |
775 | /* Now we can release all the chained descriptors */ |
776 | list_for_each_entry_safe(desc, d, &list, node) { | |
d38a8c62 | 777 | dma_descriptor_unmap(&desc->txd); |
5fa29a17 MW |
778 | ep93xx_dma_desc_put(edmac, desc); |
779 | } | |
780 | ||
dac86a14 | 781 | dmaengine_desc_callback_invoke(&cb, NULL); |
5fa29a17 MW |
782 | } |
783 | ||
784 | static irqreturn_t ep93xx_dma_interrupt(int irq, void *dev_id) | |
785 | { | |
786 | struct ep93xx_dma_chan *edmac = dev_id; | |
6d0709d2 | 787 | struct ep93xx_dma_desc *desc; |
5fa29a17 MW |
788 | irqreturn_t ret = IRQ_HANDLED; |
789 | ||
790 | spin_lock(&edmac->lock); | |
791 | ||
6d0709d2 MW |
792 | desc = ep93xx_dma_get_active(edmac); |
793 | if (!desc) { | |
794 | dev_warn(chan2dev(edmac), | |
795 | "got interrupt while active list is empty\n"); | |
796 | spin_unlock(&edmac->lock); | |
797 | return IRQ_NONE; | |
798 | } | |
799 | ||
5fa29a17 MW |
800 | switch (edmac->edma->hw_interrupt(edmac)) { |
801 | case INTERRUPT_DONE: | |
6d0709d2 | 802 | desc->complete = true; |
5fa29a17 MW |
803 | tasklet_schedule(&edmac->tasklet); |
804 | break; | |
805 | ||
806 | case INTERRUPT_NEXT_BUFFER: | |
807 | if (test_bit(EP93XX_DMA_IS_CYCLIC, &edmac->flags)) | |
808 | tasklet_schedule(&edmac->tasklet); | |
809 | break; | |
810 | ||
811 | default: | |
812 | dev_warn(chan2dev(edmac), "unknown interrupt!\n"); | |
813 | ret = IRQ_NONE; | |
814 | break; | |
815 | } | |
816 | ||
817 | spin_unlock(&edmac->lock); | |
818 | return ret; | |
819 | } | |
820 | ||
821 | /** | |
822 | * ep93xx_dma_tx_submit - set the prepared descriptor(s) to be executed | |
823 | * @tx: descriptor to be executed | |
824 | * | |
825 | * Function will execute given descriptor on the hardware or if the hardware | |
826 | * is busy, queue the descriptor to be executed later on. Returns cookie which | |
827 | * can be used to poll the status of the descriptor. | |
828 | */ | |
829 | static dma_cookie_t ep93xx_dma_tx_submit(struct dma_async_tx_descriptor *tx) | |
830 | { | |
831 | struct ep93xx_dma_chan *edmac = to_ep93xx_dma_chan(tx->chan); | |
832 | struct ep93xx_dma_desc *desc; | |
833 | dma_cookie_t cookie; | |
834 | unsigned long flags; | |
835 | ||
836 | spin_lock_irqsave(&edmac->lock, flags); | |
884485e1 | 837 | cookie = dma_cookie_assign(tx); |
5fa29a17 MW |
838 | |
839 | desc = container_of(tx, struct ep93xx_dma_desc, txd); | |
840 | ||
5fa29a17 MW |
841 | /* |
842 | * If nothing is currently prosessed, we push this descriptor | |
843 | * directly to the hardware. Otherwise we put the descriptor | |
844 | * to the pending queue. | |
845 | */ | |
846 | if (list_empty(&edmac->active)) { | |
847 | ep93xx_dma_set_active(edmac, desc); | |
848 | edmac->edma->hw_submit(edmac); | |
849 | } else { | |
850 | list_add_tail(&desc->node, &edmac->queue); | |
851 | } | |
852 | ||
853 | spin_unlock_irqrestore(&edmac->lock, flags); | |
854 | return cookie; | |
855 | } | |
856 | ||
857 | /** | |
858 | * ep93xx_dma_alloc_chan_resources - allocate resources for the channel | |
859 | * @chan: channel to allocate resources | |
860 | * | |
861 | * Function allocates necessary resources for the given DMA channel and | |
862 | * returns number of allocated descriptors for the channel. Negative errno | |
863 | * is returned in case of failure. | |
864 | */ | |
865 | static int ep93xx_dma_alloc_chan_resources(struct dma_chan *chan) | |
866 | { | |
867 | struct ep93xx_dma_chan *edmac = to_ep93xx_dma_chan(chan); | |
868 | struct ep93xx_dma_data *data = chan->private; | |
869 | const char *name = dma_chan_name(chan); | |
870 | int ret, i; | |
871 | ||
872 | /* Sanity check the channel parameters */ | |
873 | if (!edmac->edma->m2m) { | |
874 | if (!data) | |
875 | return -EINVAL; | |
876 | if (data->port < EP93XX_DMA_I2S1 || | |
877 | data->port > EP93XX_DMA_IRDA) | |
878 | return -EINVAL; | |
879 | if (data->direction != ep93xx_dma_chan_direction(chan)) | |
880 | return -EINVAL; | |
881 | } else { | |
882 | if (data) { | |
883 | switch (data->port) { | |
884 | case EP93XX_DMA_SSP: | |
885 | case EP93XX_DMA_IDE: | |
0efcdb20 | 886 | if (!is_slave_direction(data->direction)) |
5fa29a17 MW |
887 | return -EINVAL; |
888 | break; | |
889 | default: | |
890 | return -EINVAL; | |
891 | } | |
892 | } | |
893 | } | |
894 | ||
895 | if (data && data->name) | |
896 | name = data->name; | |
897 | ||
898 | ret = clk_enable(edmac->clk); | |
899 | if (ret) | |
900 | return ret; | |
901 | ||
902 | ret = request_irq(edmac->irq, ep93xx_dma_interrupt, 0, name, edmac); | |
903 | if (ret) | |
904 | goto fail_clk_disable; | |
905 | ||
906 | spin_lock_irq(&edmac->lock); | |
d3ee98cd | 907 | dma_cookie_init(&edmac->chan); |
5fa29a17 MW |
908 | ret = edmac->edma->hw_setup(edmac); |
909 | spin_unlock_irq(&edmac->lock); | |
910 | ||
911 | if (ret) | |
912 | goto fail_free_irq; | |
913 | ||
914 | for (i = 0; i < DMA_MAX_CHAN_DESCRIPTORS; i++) { | |
915 | struct ep93xx_dma_desc *desc; | |
916 | ||
917 | desc = kzalloc(sizeof(*desc), GFP_KERNEL); | |
918 | if (!desc) { | |
919 | dev_warn(chan2dev(edmac), "not enough descriptors\n"); | |
920 | break; | |
921 | } | |
922 | ||
923 | INIT_LIST_HEAD(&desc->tx_list); | |
924 | ||
925 | dma_async_tx_descriptor_init(&desc->txd, chan); | |
926 | desc->txd.flags = DMA_CTRL_ACK; | |
927 | desc->txd.tx_submit = ep93xx_dma_tx_submit; | |
928 | ||
929 | ep93xx_dma_desc_put(edmac, desc); | |
930 | } | |
931 | ||
932 | return i; | |
933 | ||
934 | fail_free_irq: | |
935 | free_irq(edmac->irq, edmac); | |
936 | fail_clk_disable: | |
937 | clk_disable(edmac->clk); | |
938 | ||
939 | return ret; | |
940 | } | |
941 | ||
942 | /** | |
943 | * ep93xx_dma_free_chan_resources - release resources for the channel | |
944 | * @chan: channel | |
945 | * | |
946 | * Function releases all the resources allocated for the given channel. | |
947 | * The channel must be idle when this is called. | |
948 | */ | |
949 | static void ep93xx_dma_free_chan_resources(struct dma_chan *chan) | |
950 | { | |
951 | struct ep93xx_dma_chan *edmac = to_ep93xx_dma_chan(chan); | |
952 | struct ep93xx_dma_desc *desc, *d; | |
953 | unsigned long flags; | |
954 | LIST_HEAD(list); | |
955 | ||
956 | BUG_ON(!list_empty(&edmac->active)); | |
957 | BUG_ON(!list_empty(&edmac->queue)); | |
958 | ||
959 | spin_lock_irqsave(&edmac->lock, flags); | |
960 | edmac->edma->hw_shutdown(edmac); | |
961 | edmac->runtime_addr = 0; | |
962 | edmac->runtime_ctrl = 0; | |
963 | edmac->buffer = 0; | |
964 | list_splice_init(&edmac->free_list, &list); | |
965 | spin_unlock_irqrestore(&edmac->lock, flags); | |
966 | ||
967 | list_for_each_entry_safe(desc, d, &list, node) | |
968 | kfree(desc); | |
969 | ||
970 | clk_disable(edmac->clk); | |
971 | free_irq(edmac->irq, edmac); | |
972 | } | |
973 | ||
974 | /** | |
975 | * ep93xx_dma_prep_dma_memcpy - prepare a memcpy DMA operation | |
976 | * @chan: channel | |
977 | * @dest: destination bus address | |
978 | * @src: source bus address | |
979 | * @len: size of the transaction | |
980 | * @flags: flags for the descriptor | |
981 | * | |
982 | * Returns a valid DMA descriptor or %NULL in case of failure. | |
983 | */ | |
e2f5e5a7 | 984 | static struct dma_async_tx_descriptor * |
5fa29a17 MW |
985 | ep93xx_dma_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, |
986 | dma_addr_t src, size_t len, unsigned long flags) | |
987 | { | |
988 | struct ep93xx_dma_chan *edmac = to_ep93xx_dma_chan(chan); | |
989 | struct ep93xx_dma_desc *desc, *first; | |
990 | size_t bytes, offset; | |
991 | ||
992 | first = NULL; | |
993 | for (offset = 0; offset < len; offset += bytes) { | |
994 | desc = ep93xx_dma_desc_get(edmac); | |
995 | if (!desc) { | |
9b68cc01 | 996 | dev_warn(chan2dev(edmac), "couldn't get descriptor\n"); |
5fa29a17 MW |
997 | goto fail; |
998 | } | |
999 | ||
1000 | bytes = min_t(size_t, len - offset, DMA_MAX_CHAN_BYTES); | |
1001 | ||
1002 | desc->src_addr = src + offset; | |
1003 | desc->dst_addr = dest + offset; | |
1004 | desc->size = bytes; | |
1005 | ||
1006 | if (!first) | |
1007 | first = desc; | |
1008 | else | |
1009 | list_add_tail(&desc->node, &first->tx_list); | |
1010 | } | |
1011 | ||
1012 | first->txd.cookie = -EBUSY; | |
1013 | first->txd.flags = flags; | |
1014 | ||
1015 | return &first->txd; | |
1016 | fail: | |
1017 | ep93xx_dma_desc_put(edmac, first); | |
1018 | return NULL; | |
1019 | } | |
1020 | ||
1021 | /** | |
1022 | * ep93xx_dma_prep_slave_sg - prepare a slave DMA operation | |
1023 | * @chan: channel | |
1024 | * @sgl: list of buffers to transfer | |
1025 | * @sg_len: number of entries in @sgl | |
1026 | * @dir: direction of tha DMA transfer | |
1027 | * @flags: flags for the descriptor | |
185ecb5f | 1028 | * @context: operation context (ignored) |
5fa29a17 MW |
1029 | * |
1030 | * Returns a valid DMA descriptor or %NULL in case of failure. | |
1031 | */ | |
1032 | static struct dma_async_tx_descriptor * | |
1033 | ep93xx_dma_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, | |
db8196df | 1034 | unsigned int sg_len, enum dma_transfer_direction dir, |
185ecb5f | 1035 | unsigned long flags, void *context) |
5fa29a17 MW |
1036 | { |
1037 | struct ep93xx_dma_chan *edmac = to_ep93xx_dma_chan(chan); | |
1038 | struct ep93xx_dma_desc *desc, *first; | |
1039 | struct scatterlist *sg; | |
1040 | int i; | |
1041 | ||
1042 | if (!edmac->edma->m2m && dir != ep93xx_dma_chan_direction(chan)) { | |
1043 | dev_warn(chan2dev(edmac), | |
1044 | "channel was configured with different direction\n"); | |
1045 | return NULL; | |
1046 | } | |
1047 | ||
1048 | if (test_bit(EP93XX_DMA_IS_CYCLIC, &edmac->flags)) { | |
1049 | dev_warn(chan2dev(edmac), | |
1050 | "channel is already used for cyclic transfers\n"); | |
1051 | return NULL; | |
1052 | } | |
1053 | ||
4e3c4040 VK |
1054 | ep93xx_dma_slave_config_write(chan, dir, &edmac->slave_config); |
1055 | ||
5fa29a17 MW |
1056 | first = NULL; |
1057 | for_each_sg(sgl, sg, sg_len, i) { | |
8f913bff | 1058 | size_t len = sg_dma_len(sg); |
5fa29a17 | 1059 | |
8f913bff | 1060 | if (len > DMA_MAX_CHAN_BYTES) { |
567df5e9 | 1061 | dev_warn(chan2dev(edmac), "too big transfer size %zu\n", |
8f913bff | 1062 | len); |
5fa29a17 MW |
1063 | goto fail; |
1064 | } | |
1065 | ||
1066 | desc = ep93xx_dma_desc_get(edmac); | |
1067 | if (!desc) { | |
9b68cc01 | 1068 | dev_warn(chan2dev(edmac), "couldn't get descriptor\n"); |
5fa29a17 MW |
1069 | goto fail; |
1070 | } | |
1071 | ||
db8196df | 1072 | if (dir == DMA_MEM_TO_DEV) { |
5fa29a17 MW |
1073 | desc->src_addr = sg_dma_address(sg); |
1074 | desc->dst_addr = edmac->runtime_addr; | |
1075 | } else { | |
1076 | desc->src_addr = edmac->runtime_addr; | |
1077 | desc->dst_addr = sg_dma_address(sg); | |
1078 | } | |
8f913bff | 1079 | desc->size = len; |
5fa29a17 MW |
1080 | |
1081 | if (!first) | |
1082 | first = desc; | |
1083 | else | |
1084 | list_add_tail(&desc->node, &first->tx_list); | |
1085 | } | |
1086 | ||
1087 | first->txd.cookie = -EBUSY; | |
1088 | first->txd.flags = flags; | |
1089 | ||
1090 | return &first->txd; | |
1091 | ||
1092 | fail: | |
1093 | ep93xx_dma_desc_put(edmac, first); | |
1094 | return NULL; | |
1095 | } | |
1096 | ||
1097 | /** | |
1098 | * ep93xx_dma_prep_dma_cyclic - prepare a cyclic DMA operation | |
1099 | * @chan: channel | |
1100 | * @dma_addr: DMA mapped address of the buffer | |
1101 | * @buf_len: length of the buffer (in bytes) | |
d73111c6 | 1102 | * @period_len: length of a single period |
5fa29a17 | 1103 | * @dir: direction of the operation |
ec8b5e48 | 1104 | * @flags: tx descriptor status flags |
5fa29a17 MW |
1105 | * |
1106 | * Prepares a descriptor for cyclic DMA operation. This means that once the | |
1107 | * descriptor is submitted, we will be submitting in a @period_len sized | |
1108 | * buffers and calling callback once the period has been elapsed. Transfer | |
1109 | * terminates only when client calls dmaengine_terminate_all() for this | |
1110 | * channel. | |
1111 | * | |
1112 | * Returns a valid DMA descriptor or %NULL in case of failure. | |
1113 | */ | |
1114 | static struct dma_async_tx_descriptor * | |
1115 | ep93xx_dma_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t dma_addr, | |
1116 | size_t buf_len, size_t period_len, | |
31c1e5a1 | 1117 | enum dma_transfer_direction dir, unsigned long flags) |
5fa29a17 MW |
1118 | { |
1119 | struct ep93xx_dma_chan *edmac = to_ep93xx_dma_chan(chan); | |
1120 | struct ep93xx_dma_desc *desc, *first; | |
1121 | size_t offset = 0; | |
1122 | ||
1123 | if (!edmac->edma->m2m && dir != ep93xx_dma_chan_direction(chan)) { | |
1124 | dev_warn(chan2dev(edmac), | |
1125 | "channel was configured with different direction\n"); | |
1126 | return NULL; | |
1127 | } | |
1128 | ||
1129 | if (test_and_set_bit(EP93XX_DMA_IS_CYCLIC, &edmac->flags)) { | |
1130 | dev_warn(chan2dev(edmac), | |
1131 | "channel is already used for cyclic transfers\n"); | |
1132 | return NULL; | |
1133 | } | |
1134 | ||
1135 | if (period_len > DMA_MAX_CHAN_BYTES) { | |
567df5e9 | 1136 | dev_warn(chan2dev(edmac), "too big period length %zu\n", |
5fa29a17 MW |
1137 | period_len); |
1138 | return NULL; | |
1139 | } | |
1140 | ||
4e3c4040 VK |
1141 | ep93xx_dma_slave_config_write(chan, dir, &edmac->slave_config); |
1142 | ||
5fa29a17 MW |
1143 | /* Split the buffer into period size chunks */ |
1144 | first = NULL; | |
1145 | for (offset = 0; offset < buf_len; offset += period_len) { | |
1146 | desc = ep93xx_dma_desc_get(edmac); | |
1147 | if (!desc) { | |
9b68cc01 | 1148 | dev_warn(chan2dev(edmac), "couldn't get descriptor\n"); |
5fa29a17 MW |
1149 | goto fail; |
1150 | } | |
1151 | ||
db8196df | 1152 | if (dir == DMA_MEM_TO_DEV) { |
5fa29a17 MW |
1153 | desc->src_addr = dma_addr + offset; |
1154 | desc->dst_addr = edmac->runtime_addr; | |
1155 | } else { | |
1156 | desc->src_addr = edmac->runtime_addr; | |
1157 | desc->dst_addr = dma_addr + offset; | |
1158 | } | |
1159 | ||
1160 | desc->size = period_len; | |
1161 | ||
1162 | if (!first) | |
1163 | first = desc; | |
1164 | else | |
1165 | list_add_tail(&desc->node, &first->tx_list); | |
1166 | } | |
1167 | ||
1168 | first->txd.cookie = -EBUSY; | |
1169 | ||
1170 | return &first->txd; | |
1171 | ||
1172 | fail: | |
1173 | ep93xx_dma_desc_put(edmac, first); | |
1174 | return NULL; | |
1175 | } | |
1176 | ||
98f9de36 AS |
1177 | /** |
1178 | * ep93xx_dma_synchronize - Synchronizes the termination of transfers to the | |
1179 | * current context. | |
1180 | * @chan: channel | |
1181 | * | |
1182 | * Synchronizes the DMA channel termination to the current context. When this | |
1183 | * function returns it is guaranteed that all transfers for previously issued | |
1184 | * descriptors have stopped and and it is safe to free the memory associated | |
1185 | * with them. Furthermore it is guaranteed that all complete callback functions | |
1186 | * for a previously submitted descriptor have finished running and it is safe to | |
1187 | * free resources accessed from within the complete callbacks. | |
1188 | */ | |
1189 | static void ep93xx_dma_synchronize(struct dma_chan *chan) | |
1190 | { | |
1191 | struct ep93xx_dma_chan *edmac = to_ep93xx_dma_chan(chan); | |
1192 | ||
1193 | if (edmac->edma->hw_synchronize) | |
1194 | edmac->edma->hw_synchronize(edmac); | |
1195 | } | |
1196 | ||
5fa29a17 MW |
1197 | /** |
1198 | * ep93xx_dma_terminate_all - terminate all transactions | |
2258b675 | 1199 | * @chan: channel |
5fa29a17 MW |
1200 | * |
1201 | * Stops all DMA transactions. All descriptors are put back to the | |
1202 | * @edmac->free_list and callbacks are _not_ called. | |
1203 | */ | |
2258b675 | 1204 | static int ep93xx_dma_terminate_all(struct dma_chan *chan) |
5fa29a17 | 1205 | { |
2258b675 | 1206 | struct ep93xx_dma_chan *edmac = to_ep93xx_dma_chan(chan); |
5fa29a17 MW |
1207 | struct ep93xx_dma_desc *desc, *_d; |
1208 | unsigned long flags; | |
1209 | LIST_HEAD(list); | |
1210 | ||
1211 | spin_lock_irqsave(&edmac->lock, flags); | |
1212 | /* First we disable and flush the DMA channel */ | |
1213 | edmac->edma->hw_shutdown(edmac); | |
1214 | clear_bit(EP93XX_DMA_IS_CYCLIC, &edmac->flags); | |
1215 | list_splice_init(&edmac->active, &list); | |
1216 | list_splice_init(&edmac->queue, &list); | |
1217 | /* | |
1218 | * We then re-enable the channel. This way we can continue submitting | |
1219 | * the descriptors by just calling ->hw_submit() again. | |
1220 | */ | |
1221 | edmac->edma->hw_setup(edmac); | |
1222 | spin_unlock_irqrestore(&edmac->lock, flags); | |
1223 | ||
1224 | list_for_each_entry_safe(desc, _d, &list, node) | |
1225 | ep93xx_dma_desc_put(edmac, desc); | |
1226 | ||
1227 | return 0; | |
1228 | } | |
1229 | ||
2258b675 | 1230 | static int ep93xx_dma_slave_config(struct dma_chan *chan, |
5fa29a17 MW |
1231 | struct dma_slave_config *config) |
1232 | { | |
2258b675 | 1233 | struct ep93xx_dma_chan *edmac = to_ep93xx_dma_chan(chan); |
4e3c4040 VK |
1234 | |
1235 | memcpy(&edmac->slave_config, config, sizeof(*config)); | |
1236 | ||
1237 | return 0; | |
1238 | } | |
1239 | ||
1240 | static int ep93xx_dma_slave_config_write(struct dma_chan *chan, | |
1241 | enum dma_transfer_direction dir, | |
1242 | struct dma_slave_config *config) | |
1243 | { | |
1244 | struct ep93xx_dma_chan *edmac = to_ep93xx_dma_chan(chan); | |
5fa29a17 MW |
1245 | enum dma_slave_buswidth width; |
1246 | unsigned long flags; | |
1247 | u32 addr, ctrl; | |
1248 | ||
1249 | if (!edmac->edma->m2m) | |
1250 | return -EINVAL; | |
1251 | ||
4e3c4040 | 1252 | switch (dir) { |
db8196df | 1253 | case DMA_DEV_TO_MEM: |
5fa29a17 MW |
1254 | width = config->src_addr_width; |
1255 | addr = config->src_addr; | |
1256 | break; | |
1257 | ||
db8196df | 1258 | case DMA_MEM_TO_DEV: |
5fa29a17 MW |
1259 | width = config->dst_addr_width; |
1260 | addr = config->dst_addr; | |
1261 | break; | |
1262 | ||
1263 | default: | |
1264 | return -EINVAL; | |
1265 | } | |
1266 | ||
1267 | switch (width) { | |
1268 | case DMA_SLAVE_BUSWIDTH_1_BYTE: | |
1269 | ctrl = 0; | |
1270 | break; | |
1271 | case DMA_SLAVE_BUSWIDTH_2_BYTES: | |
1272 | ctrl = M2M_CONTROL_PW_16; | |
1273 | break; | |
1274 | case DMA_SLAVE_BUSWIDTH_4_BYTES: | |
1275 | ctrl = M2M_CONTROL_PW_32; | |
1276 | break; | |
1277 | default: | |
1278 | return -EINVAL; | |
1279 | } | |
1280 | ||
1281 | spin_lock_irqsave(&edmac->lock, flags); | |
1282 | edmac->runtime_addr = addr; | |
1283 | edmac->runtime_ctrl = ctrl; | |
1284 | spin_unlock_irqrestore(&edmac->lock, flags); | |
1285 | ||
1286 | return 0; | |
1287 | } | |
1288 | ||
5fa29a17 MW |
1289 | /** |
1290 | * ep93xx_dma_tx_status - check if a transaction is completed | |
1291 | * @chan: channel | |
1292 | * @cookie: transaction specific cookie | |
1293 | * @state: state of the transaction is stored here if given | |
1294 | * | |
1295 | * This function can be used to query state of a given transaction. | |
1296 | */ | |
1297 | static enum dma_status ep93xx_dma_tx_status(struct dma_chan *chan, | |
1298 | dma_cookie_t cookie, | |
1299 | struct dma_tx_state *state) | |
1300 | { | |
2302cec2 | 1301 | return dma_cookie_status(chan, cookie, state); |
5fa29a17 MW |
1302 | } |
1303 | ||
1304 | /** | |
1305 | * ep93xx_dma_issue_pending - push pending transactions to the hardware | |
1306 | * @chan: channel | |
1307 | * | |
1308 | * When this function is called, all pending transactions are pushed to the | |
1309 | * hardware and executed. | |
1310 | */ | |
1311 | static void ep93xx_dma_issue_pending(struct dma_chan *chan) | |
1312 | { | |
1313 | ep93xx_dma_advance_work(to_ep93xx_dma_chan(chan)); | |
1314 | } | |
1315 | ||
1316 | static int __init ep93xx_dma_probe(struct platform_device *pdev) | |
1317 | { | |
1318 | struct ep93xx_dma_platform_data *pdata = dev_get_platdata(&pdev->dev); | |
1319 | struct ep93xx_dma_engine *edma; | |
1320 | struct dma_device *dma_dev; | |
1321 | size_t edma_size; | |
1322 | int ret, i; | |
1323 | ||
1324 | edma_size = pdata->num_channels * sizeof(struct ep93xx_dma_chan); | |
1325 | edma = kzalloc(sizeof(*edma) + edma_size, GFP_KERNEL); | |
1326 | if (!edma) | |
1327 | return -ENOMEM; | |
1328 | ||
1329 | dma_dev = &edma->dma_dev; | |
1330 | edma->m2m = platform_get_device_id(pdev)->driver_data; | |
1331 | edma->num_channels = pdata->num_channels; | |
1332 | ||
1333 | INIT_LIST_HEAD(&dma_dev->channels); | |
1334 | for (i = 0; i < pdata->num_channels; i++) { | |
1335 | const struct ep93xx_dma_chan_data *cdata = &pdata->channels[i]; | |
1336 | struct ep93xx_dma_chan *edmac = &edma->channels[i]; | |
1337 | ||
1338 | edmac->chan.device = dma_dev; | |
1339 | edmac->regs = cdata->base; | |
1340 | edmac->irq = cdata->irq; | |
1341 | edmac->edma = edma; | |
1342 | ||
1343 | edmac->clk = clk_get(NULL, cdata->name); | |
1344 | if (IS_ERR(edmac->clk)) { | |
1345 | dev_warn(&pdev->dev, "failed to get clock for %s\n", | |
1346 | cdata->name); | |
1347 | continue; | |
1348 | } | |
1349 | ||
1350 | spin_lock_init(&edmac->lock); | |
1351 | INIT_LIST_HEAD(&edmac->active); | |
1352 | INIT_LIST_HEAD(&edmac->queue); | |
1353 | INIT_LIST_HEAD(&edmac->free_list); | |
1354 | tasklet_init(&edmac->tasklet, ep93xx_dma_tasklet, | |
1355 | (unsigned long)edmac); | |
1356 | ||
1357 | list_add_tail(&edmac->chan.device_node, | |
1358 | &dma_dev->channels); | |
1359 | } | |
1360 | ||
1361 | dma_cap_zero(dma_dev->cap_mask); | |
1362 | dma_cap_set(DMA_SLAVE, dma_dev->cap_mask); | |
1363 | dma_cap_set(DMA_CYCLIC, dma_dev->cap_mask); | |
1364 | ||
1365 | dma_dev->dev = &pdev->dev; | |
1366 | dma_dev->device_alloc_chan_resources = ep93xx_dma_alloc_chan_resources; | |
1367 | dma_dev->device_free_chan_resources = ep93xx_dma_free_chan_resources; | |
1368 | dma_dev->device_prep_slave_sg = ep93xx_dma_prep_slave_sg; | |
1369 | dma_dev->device_prep_dma_cyclic = ep93xx_dma_prep_dma_cyclic; | |
2258b675 | 1370 | dma_dev->device_config = ep93xx_dma_slave_config; |
98f9de36 | 1371 | dma_dev->device_synchronize = ep93xx_dma_synchronize; |
2258b675 | 1372 | dma_dev->device_terminate_all = ep93xx_dma_terminate_all; |
5fa29a17 MW |
1373 | dma_dev->device_issue_pending = ep93xx_dma_issue_pending; |
1374 | dma_dev->device_tx_status = ep93xx_dma_tx_status; | |
1375 | ||
1376 | dma_set_max_seg_size(dma_dev->dev, DMA_MAX_CHAN_BYTES); | |
1377 | ||
1378 | if (edma->m2m) { | |
1379 | dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask); | |
1380 | dma_dev->device_prep_dma_memcpy = ep93xx_dma_prep_dma_memcpy; | |
1381 | ||
1382 | edma->hw_setup = m2m_hw_setup; | |
1383 | edma->hw_shutdown = m2m_hw_shutdown; | |
1384 | edma->hw_submit = m2m_hw_submit; | |
1385 | edma->hw_interrupt = m2m_hw_interrupt; | |
1386 | } else { | |
1387 | dma_cap_set(DMA_PRIVATE, dma_dev->cap_mask); | |
1388 | ||
98f9de36 | 1389 | edma->hw_synchronize = m2p_hw_synchronize; |
5fa29a17 MW |
1390 | edma->hw_setup = m2p_hw_setup; |
1391 | edma->hw_shutdown = m2p_hw_shutdown; | |
1392 | edma->hw_submit = m2p_hw_submit; | |
1393 | edma->hw_interrupt = m2p_hw_interrupt; | |
1394 | } | |
1395 | ||
1396 | ret = dma_async_device_register(dma_dev); | |
1397 | if (unlikely(ret)) { | |
1398 | for (i = 0; i < edma->num_channels; i++) { | |
1399 | struct ep93xx_dma_chan *edmac = &edma->channels[i]; | |
1400 | if (!IS_ERR_OR_NULL(edmac->clk)) | |
1401 | clk_put(edmac->clk); | |
1402 | } | |
1403 | kfree(edma); | |
1404 | } else { | |
1405 | dev_info(dma_dev->dev, "EP93xx M2%s DMA ready\n", | |
1406 | edma->m2m ? "M" : "P"); | |
1407 | } | |
1408 | ||
1409 | return ret; | |
1410 | } | |
1411 | ||
577d2e06 | 1412 | static const struct platform_device_id ep93xx_dma_driver_ids[] = { |
5fa29a17 MW |
1413 | { "ep93xx-dma-m2p", 0 }, |
1414 | { "ep93xx-dma-m2m", 1 }, | |
1415 | { }, | |
1416 | }; | |
1417 | ||
1418 | static struct platform_driver ep93xx_dma_driver = { | |
1419 | .driver = { | |
1420 | .name = "ep93xx-dma", | |
1421 | }, | |
1422 | .id_table = ep93xx_dma_driver_ids, | |
1423 | }; | |
1424 | ||
1425 | static int __init ep93xx_dma_module_init(void) | |
1426 | { | |
1427 | return platform_driver_probe(&ep93xx_dma_driver, ep93xx_dma_probe); | |
1428 | } | |
1429 | subsys_initcall(ep93xx_dma_module_init); | |
1430 | ||
1431 | MODULE_AUTHOR("Mika Westerberg <mika.westerberg@iki.fi>"); | |
1432 | MODULE_DESCRIPTION("EP93xx DMA driver"); | |
1433 | MODULE_LICENSE("GPL"); |