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2874c5fd | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
a85c6f1b SR |
2 | /* |
3 | * DMA driver for Altera mSGDMA IP core | |
4 | * | |
5 | * Copyright (C) 2017 Stefan Roese <sr@denx.de> | |
6 | * | |
7 | * Based on drivers/dma/xilinx/zynqmp_dma.c, which is: | |
8 | * Copyright (C) 2016 Xilinx, Inc. All rights reserved. | |
a85c6f1b SR |
9 | */ |
10 | ||
11 | #include <linux/bitops.h> | |
12 | #include <linux/delay.h> | |
13 | #include <linux/dma-mapping.h> | |
14 | #include <linux/dmapool.h> | |
15 | #include <linux/init.h> | |
16 | #include <linux/interrupt.h> | |
17 | #include <linux/io.h> | |
18 | #include <linux/iopoll.h> | |
19 | #include <linux/module.h> | |
20 | #include <linux/platform_device.h> | |
21 | #include <linux/slab.h> | |
65675842 | 22 | #include <linux/of_dma.h> |
a85c6f1b SR |
23 | |
24 | #include "dmaengine.h" | |
25 | ||
26 | #define MSGDMA_MAX_TRANS_LEN U32_MAX | |
27 | #define MSGDMA_DESC_NUM 1024 | |
28 | ||
29 | /** | |
30 | * struct msgdma_extended_desc - implements an extended descriptor | |
31 | * @read_addr_lo: data buffer source address low bits | |
32 | * @write_addr_lo: data buffer destination address low bits | |
33 | * @len: the number of bytes to transfer per descriptor | |
34 | * @burst_seq_num: bit 31:24 write burst | |
35 | * bit 23:16 read burst | |
36 | * bit 15:00 sequence number | |
37 | * @stride: bit 31:16 write stride | |
38 | * bit 15:00 read stride | |
39 | * @read_addr_hi: data buffer source address high bits | |
40 | * @write_addr_hi: data buffer destination address high bits | |
41 | * @control: characteristics of the transfer | |
42 | */ | |
43 | struct msgdma_extended_desc { | |
44 | u32 read_addr_lo; | |
45 | u32 write_addr_lo; | |
46 | u32 len; | |
47 | u32 burst_seq_num; | |
48 | u32 stride; | |
49 | u32 read_addr_hi; | |
50 | u32 write_addr_hi; | |
51 | u32 control; | |
52 | }; | |
53 | ||
54 | /* mSGDMA descriptor control field bit definitions */ | |
55 | #define MSGDMA_DESC_CTL_SET_CH(x) ((x) & 0xff) | |
56 | #define MSGDMA_DESC_CTL_GEN_SOP BIT(8) | |
57 | #define MSGDMA_DESC_CTL_GEN_EOP BIT(9) | |
58 | #define MSGDMA_DESC_CTL_PARK_READS BIT(10) | |
59 | #define MSGDMA_DESC_CTL_PARK_WRITES BIT(11) | |
60 | #define MSGDMA_DESC_CTL_END_ON_EOP BIT(12) | |
61 | #define MSGDMA_DESC_CTL_END_ON_LEN BIT(13) | |
62 | #define MSGDMA_DESC_CTL_TR_COMP_IRQ BIT(14) | |
63 | #define MSGDMA_DESC_CTL_EARLY_IRQ BIT(15) | |
64 | #define MSGDMA_DESC_CTL_TR_ERR_IRQ GENMASK(23, 16) | |
65 | #define MSGDMA_DESC_CTL_EARLY_DONE BIT(24) | |
66 | ||
67 | /* | |
68 | * Writing "1" the "go" bit commits the entire descriptor into the | |
69 | * descriptor FIFO(s) | |
70 | */ | |
71 | #define MSGDMA_DESC_CTL_GO BIT(31) | |
72 | ||
73 | /* Tx buffer control flags */ | |
74 | #define MSGDMA_DESC_CTL_TX_FIRST (MSGDMA_DESC_CTL_GEN_SOP | \ | |
75 | MSGDMA_DESC_CTL_TR_ERR_IRQ | \ | |
76 | MSGDMA_DESC_CTL_GO) | |
77 | ||
78 | #define MSGDMA_DESC_CTL_TX_MIDDLE (MSGDMA_DESC_CTL_TR_ERR_IRQ | \ | |
79 | MSGDMA_DESC_CTL_GO) | |
80 | ||
81 | #define MSGDMA_DESC_CTL_TX_LAST (MSGDMA_DESC_CTL_GEN_EOP | \ | |
82 | MSGDMA_DESC_CTL_TR_COMP_IRQ | \ | |
83 | MSGDMA_DESC_CTL_TR_ERR_IRQ | \ | |
84 | MSGDMA_DESC_CTL_GO) | |
85 | ||
86 | #define MSGDMA_DESC_CTL_TX_SINGLE (MSGDMA_DESC_CTL_GEN_SOP | \ | |
87 | MSGDMA_DESC_CTL_GEN_EOP | \ | |
88 | MSGDMA_DESC_CTL_TR_COMP_IRQ | \ | |
89 | MSGDMA_DESC_CTL_TR_ERR_IRQ | \ | |
90 | MSGDMA_DESC_CTL_GO) | |
91 | ||
92 | #define MSGDMA_DESC_CTL_RX_SINGLE (MSGDMA_DESC_CTL_END_ON_EOP | \ | |
93 | MSGDMA_DESC_CTL_END_ON_LEN | \ | |
94 | MSGDMA_DESC_CTL_TR_COMP_IRQ | \ | |
95 | MSGDMA_DESC_CTL_EARLY_IRQ | \ | |
96 | MSGDMA_DESC_CTL_TR_ERR_IRQ | \ | |
97 | MSGDMA_DESC_CTL_GO) | |
98 | ||
99 | /* mSGDMA extended descriptor stride definitions */ | |
100 | #define MSGDMA_DESC_STRIDE_RD 0x00000001 | |
101 | #define MSGDMA_DESC_STRIDE_WR 0x00010000 | |
102 | #define MSGDMA_DESC_STRIDE_RW 0x00010001 | |
103 | ||
6084fc2e SR |
104 | /* mSGDMA dispatcher control and status register map */ |
105 | #define MSGDMA_CSR_STATUS 0x00 /* Read / Clear */ | |
106 | #define MSGDMA_CSR_CONTROL 0x04 /* Read / Write */ | |
107 | #define MSGDMA_CSR_RW_FILL_LEVEL 0x08 /* 31:16 - write fill level */ | |
108 | /* 15:00 - read fill level */ | |
109 | #define MSGDMA_CSR_RESP_FILL_LEVEL 0x0c /* response FIFO fill level */ | |
110 | #define MSGDMA_CSR_RW_SEQ_NUM 0x10 /* 31:16 - write seq number */ | |
111 | /* 15:00 - read seq number */ | |
a85c6f1b SR |
112 | |
113 | /* mSGDMA CSR status register bit definitions */ | |
114 | #define MSGDMA_CSR_STAT_BUSY BIT(0) | |
115 | #define MSGDMA_CSR_STAT_DESC_BUF_EMPTY BIT(1) | |
116 | #define MSGDMA_CSR_STAT_DESC_BUF_FULL BIT(2) | |
117 | #define MSGDMA_CSR_STAT_RESP_BUF_EMPTY BIT(3) | |
118 | #define MSGDMA_CSR_STAT_RESP_BUF_FULL BIT(4) | |
119 | #define MSGDMA_CSR_STAT_STOPPED BIT(5) | |
120 | #define MSGDMA_CSR_STAT_RESETTING BIT(6) | |
121 | #define MSGDMA_CSR_STAT_STOPPED_ON_ERR BIT(7) | |
122 | #define MSGDMA_CSR_STAT_STOPPED_ON_EARLY BIT(8) | |
123 | #define MSGDMA_CSR_STAT_IRQ BIT(9) | |
124 | #define MSGDMA_CSR_STAT_MASK GENMASK(9, 0) | |
125 | #define MSGDMA_CSR_STAT_MASK_WITHOUT_IRQ GENMASK(8, 0) | |
126 | ||
127 | #define DESC_EMPTY (MSGDMA_CSR_STAT_DESC_BUF_EMPTY | \ | |
128 | MSGDMA_CSR_STAT_RESP_BUF_EMPTY) | |
129 | ||
130 | /* mSGDMA CSR control register bit definitions */ | |
131 | #define MSGDMA_CSR_CTL_STOP BIT(0) | |
132 | #define MSGDMA_CSR_CTL_RESET BIT(1) | |
133 | #define MSGDMA_CSR_CTL_STOP_ON_ERR BIT(2) | |
134 | #define MSGDMA_CSR_CTL_STOP_ON_EARLY BIT(3) | |
135 | #define MSGDMA_CSR_CTL_GLOBAL_INTR BIT(4) | |
136 | #define MSGDMA_CSR_CTL_STOP_DESCS BIT(5) | |
137 | ||
138 | /* mSGDMA CSR fill level bits */ | |
139 | #define MSGDMA_CSR_WR_FILL_LEVEL_GET(v) (((v) & 0xffff0000) >> 16) | |
140 | #define MSGDMA_CSR_RD_FILL_LEVEL_GET(v) ((v) & 0x0000ffff) | |
141 | #define MSGDMA_CSR_RESP_FILL_LEVEL_GET(v) ((v) & 0x0000ffff) | |
142 | ||
143 | #define MSGDMA_CSR_SEQ_NUM_GET(v) (((v) & 0xffff0000) >> 16) | |
144 | ||
145 | /* mSGDMA response register map */ | |
6084fc2e SR |
146 | #define MSGDMA_RESP_BYTES_TRANSFERRED 0x00 |
147 | #define MSGDMA_RESP_STATUS 0x04 | |
a85c6f1b SR |
148 | |
149 | /* mSGDMA response register bit definitions */ | |
150 | #define MSGDMA_RESP_EARLY_TERM BIT(8) | |
151 | #define MSGDMA_RESP_ERR_MASK 0xff | |
152 | ||
153 | /** | |
154 | * struct msgdma_sw_desc - implements a sw descriptor | |
155 | * @async_tx: support for the async_tx api | |
156 | * @hw_desc: assosiated HW descriptor | |
f15f720b LJ |
157 | * @node: node to move from the free list to the tx list |
158 | * @tx_list: transmit list node | |
a85c6f1b SR |
159 | */ |
160 | struct msgdma_sw_desc { | |
161 | struct dma_async_tx_descriptor async_tx; | |
162 | struct msgdma_extended_desc hw_desc; | |
163 | struct list_head node; | |
164 | struct list_head tx_list; | |
165 | }; | |
166 | ||
f15f720b | 167 | /* |
a85c6f1b SR |
168 | * struct msgdma_device - DMA device structure |
169 | */ | |
170 | struct msgdma_device { | |
171 | spinlock_t lock; | |
172 | struct device *dev; | |
173 | struct tasklet_struct irq_tasklet; | |
174 | struct list_head pending_list; | |
175 | struct list_head free_list; | |
176 | struct list_head active_list; | |
177 | struct list_head done_list; | |
178 | u32 desc_free_cnt; | |
179 | bool idle; | |
180 | ||
181 | struct dma_device dmadev; | |
182 | struct dma_chan dmachan; | |
183 | dma_addr_t hw_desq; | |
184 | struct msgdma_sw_desc *sw_desq; | |
185 | unsigned int npendings; | |
186 | ||
187 | struct dma_slave_config slave_cfg; | |
188 | ||
189 | int irq; | |
190 | ||
191 | /* mSGDMA controller */ | |
6084fc2e | 192 | void __iomem *csr; |
a85c6f1b SR |
193 | |
194 | /* mSGDMA descriptors */ | |
6084fc2e | 195 | void __iomem *desc; |
a85c6f1b SR |
196 | |
197 | /* mSGDMA response */ | |
6084fc2e | 198 | void __iomem *resp; |
a85c6f1b SR |
199 | }; |
200 | ||
201 | #define to_mdev(chan) container_of(chan, struct msgdma_device, dmachan) | |
202 | #define tx_to_desc(tx) container_of(tx, struct msgdma_sw_desc, async_tx) | |
203 | ||
204 | /** | |
205 | * msgdma_get_descriptor - Get the sw descriptor from the pool | |
206 | * @mdev: Pointer to the Altera mSGDMA device structure | |
207 | * | |
208 | * Return: The sw descriptor | |
209 | */ | |
210 | static struct msgdma_sw_desc *msgdma_get_descriptor(struct msgdma_device *mdev) | |
211 | { | |
212 | struct msgdma_sw_desc *desc; | |
edf10919 | 213 | unsigned long flags; |
a85c6f1b | 214 | |
edf10919 | 215 | spin_lock_irqsave(&mdev->lock, flags); |
a85c6f1b SR |
216 | desc = list_first_entry(&mdev->free_list, struct msgdma_sw_desc, node); |
217 | list_del(&desc->node); | |
edf10919 | 218 | spin_unlock_irqrestore(&mdev->lock, flags); |
a85c6f1b SR |
219 | |
220 | INIT_LIST_HEAD(&desc->tx_list); | |
221 | ||
222 | return desc; | |
223 | } | |
224 | ||
225 | /** | |
226 | * msgdma_free_descriptor - Issue pending transactions | |
227 | * @mdev: Pointer to the Altera mSGDMA device structure | |
228 | * @desc: Transaction descriptor pointer | |
229 | */ | |
230 | static void msgdma_free_descriptor(struct msgdma_device *mdev, | |
231 | struct msgdma_sw_desc *desc) | |
232 | { | |
233 | struct msgdma_sw_desc *child, *next; | |
234 | ||
235 | mdev->desc_free_cnt++; | |
236 | list_add_tail(&desc->node, &mdev->free_list); | |
237 | list_for_each_entry_safe(child, next, &desc->tx_list, node) { | |
238 | mdev->desc_free_cnt++; | |
239 | list_move_tail(&child->node, &mdev->free_list); | |
240 | } | |
241 | } | |
242 | ||
243 | /** | |
244 | * msgdma_free_desc_list - Free descriptors list | |
245 | * @mdev: Pointer to the Altera mSGDMA device structure | |
246 | * @list: List to parse and delete the descriptor | |
247 | */ | |
248 | static void msgdma_free_desc_list(struct msgdma_device *mdev, | |
249 | struct list_head *list) | |
250 | { | |
251 | struct msgdma_sw_desc *desc, *next; | |
252 | ||
253 | list_for_each_entry_safe(desc, next, list, node) | |
254 | msgdma_free_descriptor(mdev, desc); | |
255 | } | |
256 | ||
257 | /** | |
258 | * msgdma_desc_config - Configure the descriptor | |
259 | * @desc: Hw descriptor pointer | |
260 | * @dst: Destination buffer address | |
261 | * @src: Source buffer address | |
262 | * @len: Transfer length | |
f15f720b | 263 | * @stride: Read/write stride value to set |
a85c6f1b SR |
264 | */ |
265 | static void msgdma_desc_config(struct msgdma_extended_desc *desc, | |
266 | dma_addr_t dst, dma_addr_t src, size_t len, | |
267 | u32 stride) | |
268 | { | |
269 | /* Set lower 32bits of src & dst addresses in the descriptor */ | |
270 | desc->read_addr_lo = lower_32_bits(src); | |
271 | desc->write_addr_lo = lower_32_bits(dst); | |
272 | ||
273 | /* Set upper 32bits of src & dst addresses in the descriptor */ | |
274 | desc->read_addr_hi = upper_32_bits(src); | |
275 | desc->write_addr_hi = upper_32_bits(dst); | |
276 | ||
277 | desc->len = len; | |
278 | desc->stride = stride; | |
279 | desc->burst_seq_num = 0; /* 0 will result in max burst length */ | |
280 | ||
281 | /* | |
282 | * Don't set interrupt on xfer end yet, this will be done later | |
283 | * for the "last" descriptor | |
284 | */ | |
285 | desc->control = MSGDMA_DESC_CTL_TR_ERR_IRQ | MSGDMA_DESC_CTL_GO | | |
286 | MSGDMA_DESC_CTL_END_ON_LEN; | |
287 | } | |
288 | ||
289 | /** | |
290 | * msgdma_desc_config_eod - Mark the descriptor as end descriptor | |
291 | * @desc: Hw descriptor pointer | |
292 | */ | |
293 | static void msgdma_desc_config_eod(struct msgdma_extended_desc *desc) | |
294 | { | |
295 | desc->control |= MSGDMA_DESC_CTL_TR_COMP_IRQ; | |
296 | } | |
297 | ||
298 | /** | |
299 | * msgdma_tx_submit - Submit DMA transaction | |
300 | * @tx: Async transaction descriptor pointer | |
301 | * | |
302 | * Return: cookie value | |
303 | */ | |
304 | static dma_cookie_t msgdma_tx_submit(struct dma_async_tx_descriptor *tx) | |
305 | { | |
306 | struct msgdma_device *mdev = to_mdev(tx->chan); | |
307 | struct msgdma_sw_desc *new; | |
308 | dma_cookie_t cookie; | |
edf10919 | 309 | unsigned long flags; |
a85c6f1b SR |
310 | |
311 | new = tx_to_desc(tx); | |
edf10919 | 312 | spin_lock_irqsave(&mdev->lock, flags); |
a85c6f1b SR |
313 | cookie = dma_cookie_assign(tx); |
314 | ||
315 | list_add_tail(&new->node, &mdev->pending_list); | |
edf10919 | 316 | spin_unlock_irqrestore(&mdev->lock, flags); |
a85c6f1b SR |
317 | |
318 | return cookie; | |
319 | } | |
320 | ||
321 | /** | |
322 | * msgdma_prep_memcpy - prepare descriptors for memcpy transaction | |
323 | * @dchan: DMA channel | |
324 | * @dma_dst: Destination buffer address | |
325 | * @dma_src: Source buffer address | |
326 | * @len: Transfer length | |
327 | * @flags: transfer ack flags | |
328 | * | |
329 | * Return: Async transaction descriptor on success and NULL on failure | |
330 | */ | |
331 | static struct dma_async_tx_descriptor * | |
332 | msgdma_prep_memcpy(struct dma_chan *dchan, dma_addr_t dma_dst, | |
333 | dma_addr_t dma_src, size_t len, ulong flags) | |
334 | { | |
335 | struct msgdma_device *mdev = to_mdev(dchan); | |
336 | struct msgdma_sw_desc *new, *first = NULL; | |
337 | struct msgdma_extended_desc *desc; | |
338 | size_t copy; | |
339 | u32 desc_cnt; | |
edf10919 | 340 | unsigned long irqflags; |
a85c6f1b SR |
341 | |
342 | desc_cnt = DIV_ROUND_UP(len, MSGDMA_MAX_TRANS_LEN); | |
343 | ||
edf10919 | 344 | spin_lock_irqsave(&mdev->lock, irqflags); |
a85c6f1b | 345 | if (desc_cnt > mdev->desc_free_cnt) { |
c5709d37 | 346 | spin_unlock_irqrestore(&mdev->lock, irqflags); |
a85c6f1b SR |
347 | dev_dbg(mdev->dev, "mdev %p descs are not available\n", mdev); |
348 | return NULL; | |
349 | } | |
350 | mdev->desc_free_cnt -= desc_cnt; | |
edf10919 | 351 | spin_unlock_irqrestore(&mdev->lock, irqflags); |
a85c6f1b SR |
352 | |
353 | do { | |
354 | /* Allocate and populate the descriptor */ | |
355 | new = msgdma_get_descriptor(mdev); | |
356 | ||
357 | copy = min_t(size_t, len, MSGDMA_MAX_TRANS_LEN); | |
358 | desc = &new->hw_desc; | |
359 | msgdma_desc_config(desc, dma_dst, dma_src, copy, | |
360 | MSGDMA_DESC_STRIDE_RW); | |
361 | len -= copy; | |
362 | dma_src += copy; | |
363 | dma_dst += copy; | |
364 | if (!first) | |
365 | first = new; | |
366 | else | |
367 | list_add_tail(&new->node, &first->tx_list); | |
368 | } while (len); | |
369 | ||
370 | msgdma_desc_config_eod(desc); | |
371 | async_tx_ack(&first->async_tx); | |
372 | first->async_tx.flags = flags; | |
373 | ||
374 | return &first->async_tx; | |
375 | } | |
376 | ||
a85c6f1b SR |
377 | /** |
378 | * msgdma_prep_slave_sg - prepare descriptors for a slave sg transaction | |
379 | * | |
380 | * @dchan: DMA channel | |
381 | * @sgl: Destination scatter list | |
382 | * @sg_len: Number of entries in destination scatter list | |
383 | * @dir: DMA transfer direction | |
384 | * @flags: transfer ack flags | |
385 | * @context: transfer context (unused) | |
386 | */ | |
387 | static struct dma_async_tx_descriptor * | |
388 | msgdma_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl, | |
389 | unsigned int sg_len, enum dma_transfer_direction dir, | |
390 | unsigned long flags, void *context) | |
391 | ||
392 | { | |
393 | struct msgdma_device *mdev = to_mdev(dchan); | |
394 | struct dma_slave_config *cfg = &mdev->slave_cfg; | |
395 | struct msgdma_sw_desc *new, *first = NULL; | |
396 | void *desc = NULL; | |
397 | size_t len, avail; | |
398 | dma_addr_t dma_dst, dma_src; | |
399 | u32 desc_cnt = 0, i; | |
400 | struct scatterlist *sg; | |
401 | u32 stride; | |
edf10919 | 402 | unsigned long irqflags; |
a85c6f1b SR |
403 | |
404 | for_each_sg(sgl, sg, sg_len, i) | |
405 | desc_cnt += DIV_ROUND_UP(sg_dma_len(sg), MSGDMA_MAX_TRANS_LEN); | |
406 | ||
edf10919 | 407 | spin_lock_irqsave(&mdev->lock, irqflags); |
a85c6f1b | 408 | if (desc_cnt > mdev->desc_free_cnt) { |
c5709d37 | 409 | spin_unlock_irqrestore(&mdev->lock, irqflags); |
a85c6f1b SR |
410 | dev_dbg(mdev->dev, "mdev %p descs are not available\n", mdev); |
411 | return NULL; | |
412 | } | |
413 | mdev->desc_free_cnt -= desc_cnt; | |
edf10919 | 414 | spin_unlock_irqrestore(&mdev->lock, irqflags); |
a85c6f1b SR |
415 | |
416 | avail = sg_dma_len(sgl); | |
417 | ||
418 | /* Run until we are out of scatterlist entries */ | |
419 | while (true) { | |
420 | /* Allocate and populate the descriptor */ | |
421 | new = msgdma_get_descriptor(mdev); | |
422 | ||
423 | desc = &new->hw_desc; | |
424 | len = min_t(size_t, avail, MSGDMA_MAX_TRANS_LEN); | |
425 | ||
426 | if (dir == DMA_MEM_TO_DEV) { | |
427 | dma_src = sg_dma_address(sgl) + sg_dma_len(sgl) - avail; | |
428 | dma_dst = cfg->dst_addr; | |
429 | stride = MSGDMA_DESC_STRIDE_RD; | |
430 | } else { | |
431 | dma_src = cfg->src_addr; | |
432 | dma_dst = sg_dma_address(sgl) + sg_dma_len(sgl) - avail; | |
433 | stride = MSGDMA_DESC_STRIDE_WR; | |
434 | } | |
435 | msgdma_desc_config(desc, dma_dst, dma_src, len, stride); | |
436 | avail -= len; | |
437 | ||
438 | if (!first) | |
439 | first = new; | |
440 | else | |
441 | list_add_tail(&new->node, &first->tx_list); | |
442 | ||
443 | /* Fetch the next scatterlist entry */ | |
444 | if (avail == 0) { | |
445 | if (sg_len == 0) | |
446 | break; | |
447 | sgl = sg_next(sgl); | |
448 | if (sgl == NULL) | |
449 | break; | |
450 | sg_len--; | |
451 | avail = sg_dma_len(sgl); | |
452 | } | |
453 | } | |
454 | ||
455 | msgdma_desc_config_eod(desc); | |
456 | first->async_tx.flags = flags; | |
457 | ||
458 | return &first->async_tx; | |
459 | } | |
460 | ||
461 | static int msgdma_dma_config(struct dma_chan *dchan, | |
462 | struct dma_slave_config *config) | |
463 | { | |
464 | struct msgdma_device *mdev = to_mdev(dchan); | |
465 | ||
466 | memcpy(&mdev->slave_cfg, config, sizeof(*config)); | |
467 | ||
468 | return 0; | |
469 | } | |
470 | ||
471 | static void msgdma_reset(struct msgdma_device *mdev) | |
472 | { | |
473 | u32 val; | |
474 | int ret; | |
475 | ||
476 | /* Reset mSGDMA */ | |
6084fc2e SR |
477 | iowrite32(MSGDMA_CSR_STAT_MASK, mdev->csr + MSGDMA_CSR_STATUS); |
478 | iowrite32(MSGDMA_CSR_CTL_RESET, mdev->csr + MSGDMA_CSR_CONTROL); | |
a85c6f1b | 479 | |
6084fc2e | 480 | ret = readl_poll_timeout(mdev->csr + MSGDMA_CSR_STATUS, val, |
a85c6f1b SR |
481 | (val & MSGDMA_CSR_STAT_RESETTING) == 0, |
482 | 1, 10000); | |
483 | if (ret) | |
484 | dev_err(mdev->dev, "DMA channel did not reset\n"); | |
485 | ||
486 | /* Clear all status bits */ | |
6084fc2e | 487 | iowrite32(MSGDMA_CSR_STAT_MASK, mdev->csr + MSGDMA_CSR_STATUS); |
a85c6f1b SR |
488 | |
489 | /* Enable the DMA controller including interrupts */ | |
490 | iowrite32(MSGDMA_CSR_CTL_STOP_ON_ERR | MSGDMA_CSR_CTL_STOP_ON_EARLY | | |
6084fc2e | 491 | MSGDMA_CSR_CTL_GLOBAL_INTR, mdev->csr + MSGDMA_CSR_CONTROL); |
a85c6f1b SR |
492 | |
493 | mdev->idle = true; | |
494 | }; | |
495 | ||
496 | static void msgdma_copy_one(struct msgdma_device *mdev, | |
497 | struct msgdma_sw_desc *desc) | |
498 | { | |
6084fc2e | 499 | void __iomem *hw_desc = mdev->desc; |
a85c6f1b SR |
500 | |
501 | /* | |
502 | * Check if the DESC FIFO it not full. If its full, we need to wait | |
503 | * for at least one entry to become free again | |
504 | */ | |
6084fc2e SR |
505 | while (ioread32(mdev->csr + MSGDMA_CSR_STATUS) & |
506 | MSGDMA_CSR_STAT_DESC_BUF_FULL) | |
a85c6f1b SR |
507 | mdelay(1); |
508 | ||
509 | /* | |
510 | * The descriptor needs to get copied into the descriptor FIFO | |
511 | * of the DMA controller. The descriptor will get flushed to the | |
512 | * FIFO, once the last word (control word) is written. Since we | |
513 | * are not 100% sure that memcpy() writes all word in the "correct" | |
514 | * oder (address from low to high) on all architectures, we make | |
515 | * sure this control word is written last by single coding it and | |
516 | * adding some write-barriers here. | |
517 | */ | |
6084fc2e SR |
518 | memcpy((void __force *)hw_desc, &desc->hw_desc, |
519 | sizeof(desc->hw_desc) - sizeof(u32)); | |
a85c6f1b SR |
520 | |
521 | /* Write control word last to flush this descriptor into the FIFO */ | |
522 | mdev->idle = false; | |
523 | wmb(); | |
6084fc2e SR |
524 | iowrite32(desc->hw_desc.control, hw_desc + |
525 | offsetof(struct msgdma_extended_desc, control)); | |
a85c6f1b SR |
526 | wmb(); |
527 | } | |
528 | ||
529 | /** | |
530 | * msgdma_copy_desc_to_fifo - copy descriptor(s) into controller FIFO | |
531 | * @mdev: Pointer to the Altera mSGDMA device structure | |
532 | * @desc: Transaction descriptor pointer | |
533 | */ | |
534 | static void msgdma_copy_desc_to_fifo(struct msgdma_device *mdev, | |
535 | struct msgdma_sw_desc *desc) | |
536 | { | |
537 | struct msgdma_sw_desc *sdesc, *next; | |
538 | ||
539 | msgdma_copy_one(mdev, desc); | |
540 | ||
541 | list_for_each_entry_safe(sdesc, next, &desc->tx_list, node) | |
542 | msgdma_copy_one(mdev, sdesc); | |
543 | } | |
544 | ||
545 | /** | |
546 | * msgdma_start_transfer - Initiate the new transfer | |
547 | * @mdev: Pointer to the Altera mSGDMA device structure | |
548 | */ | |
549 | static void msgdma_start_transfer(struct msgdma_device *mdev) | |
550 | { | |
551 | struct msgdma_sw_desc *desc; | |
552 | ||
553 | if (!mdev->idle) | |
554 | return; | |
555 | ||
556 | desc = list_first_entry_or_null(&mdev->pending_list, | |
557 | struct msgdma_sw_desc, node); | |
558 | if (!desc) | |
559 | return; | |
560 | ||
561 | list_splice_tail_init(&mdev->pending_list, &mdev->active_list); | |
562 | msgdma_copy_desc_to_fifo(mdev, desc); | |
563 | } | |
564 | ||
565 | /** | |
566 | * msgdma_issue_pending - Issue pending transactions | |
567 | * @chan: DMA channel pointer | |
568 | */ | |
569 | static void msgdma_issue_pending(struct dma_chan *chan) | |
570 | { | |
571 | struct msgdma_device *mdev = to_mdev(chan); | |
edf10919 | 572 | unsigned long flags; |
a85c6f1b | 573 | |
edf10919 | 574 | spin_lock_irqsave(&mdev->lock, flags); |
a85c6f1b | 575 | msgdma_start_transfer(mdev); |
edf10919 | 576 | spin_unlock_irqrestore(&mdev->lock, flags); |
a85c6f1b SR |
577 | } |
578 | ||
579 | /** | |
580 | * msgdma_chan_desc_cleanup - Cleanup the completed descriptors | |
581 | * @mdev: Pointer to the Altera mSGDMA device structure | |
582 | */ | |
583 | static void msgdma_chan_desc_cleanup(struct msgdma_device *mdev) | |
584 | { | |
585 | struct msgdma_sw_desc *desc, *next; | |
586 | ||
587 | list_for_each_entry_safe(desc, next, &mdev->done_list, node) { | |
a34da7ef | 588 | struct dmaengine_desc_callback cb; |
a85c6f1b SR |
589 | |
590 | list_del(&desc->node); | |
591 | ||
a34da7ef LPC |
592 | dmaengine_desc_get_callback(&desc->async_tx, &cb); |
593 | if (dmaengine_desc_callback_valid(&cb)) { | |
a85c6f1b | 594 | spin_unlock(&mdev->lock); |
a34da7ef | 595 | dmaengine_desc_callback_invoke(&cb, NULL); |
a85c6f1b SR |
596 | spin_lock(&mdev->lock); |
597 | } | |
598 | ||
599 | /* Run any dependencies, then free the descriptor */ | |
600 | msgdma_free_descriptor(mdev, desc); | |
601 | } | |
602 | } | |
603 | ||
604 | /** | |
605 | * msgdma_complete_descriptor - Mark the active descriptor as complete | |
606 | * @mdev: Pointer to the Altera mSGDMA device structure | |
607 | */ | |
608 | static void msgdma_complete_descriptor(struct msgdma_device *mdev) | |
609 | { | |
610 | struct msgdma_sw_desc *desc; | |
611 | ||
612 | desc = list_first_entry_or_null(&mdev->active_list, | |
613 | struct msgdma_sw_desc, node); | |
614 | if (!desc) | |
615 | return; | |
616 | list_del(&desc->node); | |
617 | dma_cookie_complete(&desc->async_tx); | |
618 | list_add_tail(&desc->node, &mdev->done_list); | |
619 | } | |
620 | ||
621 | /** | |
622 | * msgdma_free_descriptors - Free channel descriptors | |
623 | * @mdev: Pointer to the Altera mSGDMA device structure | |
624 | */ | |
625 | static void msgdma_free_descriptors(struct msgdma_device *mdev) | |
626 | { | |
627 | msgdma_free_desc_list(mdev, &mdev->active_list); | |
628 | msgdma_free_desc_list(mdev, &mdev->pending_list); | |
629 | msgdma_free_desc_list(mdev, &mdev->done_list); | |
630 | } | |
631 | ||
632 | /** | |
633 | * msgdma_free_chan_resources - Free channel resources | |
634 | * @dchan: DMA channel pointer | |
635 | */ | |
636 | static void msgdma_free_chan_resources(struct dma_chan *dchan) | |
637 | { | |
638 | struct msgdma_device *mdev = to_mdev(dchan); | |
edf10919 | 639 | unsigned long flags; |
a85c6f1b | 640 | |
edf10919 | 641 | spin_lock_irqsave(&mdev->lock, flags); |
a85c6f1b | 642 | msgdma_free_descriptors(mdev); |
edf10919 | 643 | spin_unlock_irqrestore(&mdev->lock, flags); |
a85c6f1b SR |
644 | kfree(mdev->sw_desq); |
645 | } | |
646 | ||
647 | /** | |
648 | * msgdma_alloc_chan_resources - Allocate channel resources | |
649 | * @dchan: DMA channel | |
650 | * | |
651 | * Return: Number of descriptors on success and failure value on error | |
652 | */ | |
653 | static int msgdma_alloc_chan_resources(struct dma_chan *dchan) | |
654 | { | |
655 | struct msgdma_device *mdev = to_mdev(dchan); | |
656 | struct msgdma_sw_desc *desc; | |
657 | int i; | |
658 | ||
659 | mdev->sw_desq = kcalloc(MSGDMA_DESC_NUM, sizeof(*desc), GFP_NOWAIT); | |
660 | if (!mdev->sw_desq) | |
661 | return -ENOMEM; | |
662 | ||
663 | mdev->idle = true; | |
664 | mdev->desc_free_cnt = MSGDMA_DESC_NUM; | |
665 | ||
666 | INIT_LIST_HEAD(&mdev->free_list); | |
667 | ||
668 | for (i = 0; i < MSGDMA_DESC_NUM; i++) { | |
669 | desc = mdev->sw_desq + i; | |
670 | dma_async_tx_descriptor_init(&desc->async_tx, &mdev->dmachan); | |
671 | desc->async_tx.tx_submit = msgdma_tx_submit; | |
672 | list_add_tail(&desc->node, &mdev->free_list); | |
673 | } | |
674 | ||
675 | return MSGDMA_DESC_NUM; | |
676 | } | |
677 | ||
678 | /** | |
679 | * msgdma_tasklet - Schedule completion tasklet | |
62e13a58 | 680 | * @t: Pointer to the Altera sSGDMA channel structure |
a85c6f1b | 681 | */ |
6752e40d | 682 | static void msgdma_tasklet(struct tasklet_struct *t) |
a85c6f1b | 683 | { |
6752e40d | 684 | struct msgdma_device *mdev = from_tasklet(mdev, t, irq_tasklet); |
a85c6f1b | 685 | u32 count; |
6084fc2e SR |
686 | u32 __maybe_unused size; |
687 | u32 __maybe_unused status; | |
edf10919 | 688 | unsigned long flags; |
a85c6f1b | 689 | |
edf10919 | 690 | spin_lock_irqsave(&mdev->lock, flags); |
a85c6f1b | 691 | |
af2eec75 OD |
692 | if (mdev->resp) { |
693 | /* Read number of responses that are available */ | |
694 | count = ioread32(mdev->csr + MSGDMA_CSR_RESP_FILL_LEVEL); | |
695 | dev_dbg(mdev->dev, "%s (%d): response count=%d\n", | |
696 | __func__, __LINE__, count); | |
697 | } else { | |
698 | count = 1; | |
699 | } | |
a85c6f1b SR |
700 | |
701 | while (count--) { | |
702 | /* | |
703 | * Read both longwords to purge this response from the FIFO | |
704 | * On Avalon-MM implementations, size and status do not | |
705 | * have any real values, like transferred bytes or error | |
706 | * bits. So we need to just drop these values. | |
707 | */ | |
af2eec75 OD |
708 | if (mdev->resp) { |
709 | size = ioread32(mdev->resp + | |
710 | MSGDMA_RESP_BYTES_TRANSFERRED); | |
711 | status = ioread32(mdev->resp + | |
712 | MSGDMA_RESP_STATUS); | |
713 | } | |
a85c6f1b SR |
714 | |
715 | msgdma_complete_descriptor(mdev); | |
716 | msgdma_chan_desc_cleanup(mdev); | |
717 | } | |
718 | ||
edf10919 | 719 | spin_unlock_irqrestore(&mdev->lock, flags); |
a85c6f1b SR |
720 | } |
721 | ||
722 | /** | |
723 | * msgdma_irq_handler - Altera mSGDMA Interrupt handler | |
724 | * @irq: IRQ number | |
725 | * @data: Pointer to the Altera mSGDMA device structure | |
726 | * | |
727 | * Return: IRQ_HANDLED/IRQ_NONE | |
728 | */ | |
729 | static irqreturn_t msgdma_irq_handler(int irq, void *data) | |
730 | { | |
731 | struct msgdma_device *mdev = data; | |
732 | u32 status; | |
733 | ||
6084fc2e | 734 | status = ioread32(mdev->csr + MSGDMA_CSR_STATUS); |
a85c6f1b SR |
735 | if ((status & MSGDMA_CSR_STAT_BUSY) == 0) { |
736 | /* Start next transfer if the DMA controller is idle */ | |
737 | spin_lock(&mdev->lock); | |
738 | mdev->idle = true; | |
739 | msgdma_start_transfer(mdev); | |
740 | spin_unlock(&mdev->lock); | |
741 | } | |
742 | ||
743 | tasklet_schedule(&mdev->irq_tasklet); | |
744 | ||
745 | /* Clear interrupt in mSGDMA controller */ | |
6084fc2e | 746 | iowrite32(MSGDMA_CSR_STAT_IRQ, mdev->csr + MSGDMA_CSR_STATUS); |
a85c6f1b SR |
747 | |
748 | return IRQ_HANDLED; | |
749 | } | |
750 | ||
751 | /** | |
752 | * msgdma_chan_remove - Channel remove function | |
753 | * @mdev: Pointer to the Altera mSGDMA device structure | |
754 | */ | |
755 | static void msgdma_dev_remove(struct msgdma_device *mdev) | |
756 | { | |
757 | if (!mdev) | |
758 | return; | |
759 | ||
760 | devm_free_irq(mdev->dev, mdev->irq, mdev); | |
761 | tasklet_kill(&mdev->irq_tasklet); | |
762 | list_del(&mdev->dmachan.device_node); | |
763 | } | |
764 | ||
765 | static int request_and_map(struct platform_device *pdev, const char *name, | |
af2eec75 OD |
766 | struct resource **res, void __iomem **ptr, |
767 | bool optional) | |
a85c6f1b SR |
768 | { |
769 | struct resource *region; | |
770 | struct device *device = &pdev->dev; | |
771 | ||
772 | *res = platform_get_resource_byname(pdev, IORESOURCE_MEM, name); | |
773 | if (*res == NULL) { | |
af2eec75 OD |
774 | if (optional) { |
775 | *ptr = NULL; | |
776 | dev_info(device, "optional resource %s not defined\n", | |
777 | name); | |
778 | return 0; | |
779 | } | |
780 | dev_err(device, "mandatory resource %s not defined\n", name); | |
a85c6f1b SR |
781 | return -ENODEV; |
782 | } | |
783 | ||
784 | region = devm_request_mem_region(device, (*res)->start, | |
785 | resource_size(*res), dev_name(device)); | |
786 | if (region == NULL) { | |
787 | dev_err(device, "unable to request %s\n", name); | |
788 | return -EBUSY; | |
789 | } | |
790 | ||
4bdc0d67 | 791 | *ptr = devm_ioremap(device, region->start, |
a85c6f1b SR |
792 | resource_size(region)); |
793 | if (*ptr == NULL) { | |
4bdc0d67 | 794 | dev_err(device, "ioremap of %s failed!", name); |
a85c6f1b SR |
795 | return -ENOMEM; |
796 | } | |
797 | ||
798 | return 0; | |
799 | } | |
800 | ||
801 | /** | |
802 | * msgdma_probe - Driver probe function | |
803 | * @pdev: Pointer to the platform_device structure | |
804 | * | |
805 | * Return: '0' on success and failure value on error | |
806 | */ | |
807 | static int msgdma_probe(struct platform_device *pdev) | |
808 | { | |
809 | struct msgdma_device *mdev; | |
810 | struct dma_device *dma_dev; | |
811 | struct resource *dma_res; | |
812 | int ret; | |
813 | ||
814 | mdev = devm_kzalloc(&pdev->dev, sizeof(*mdev), GFP_NOWAIT); | |
815 | if (!mdev) | |
816 | return -ENOMEM; | |
817 | ||
818 | mdev->dev = &pdev->dev; | |
819 | ||
820 | /* Map CSR space */ | |
af2eec75 | 821 | ret = request_and_map(pdev, "csr", &dma_res, &mdev->csr, false); |
a85c6f1b SR |
822 | if (ret) |
823 | return ret; | |
824 | ||
825 | /* Map (extended) descriptor space */ | |
af2eec75 | 826 | ret = request_and_map(pdev, "desc", &dma_res, &mdev->desc, false); |
a85c6f1b SR |
827 | if (ret) |
828 | return ret; | |
829 | ||
830 | /* Map response space */ | |
af2eec75 | 831 | ret = request_and_map(pdev, "resp", &dma_res, &mdev->resp, true); |
a85c6f1b SR |
832 | if (ret) |
833 | return ret; | |
834 | ||
835 | platform_set_drvdata(pdev, mdev); | |
836 | ||
837 | /* Get interrupt nr from platform data */ | |
838 | mdev->irq = platform_get_irq(pdev, 0); | |
839 | if (mdev->irq < 0) | |
840 | return -ENXIO; | |
841 | ||
842 | ret = devm_request_irq(&pdev->dev, mdev->irq, msgdma_irq_handler, | |
843 | 0, dev_name(&pdev->dev), mdev); | |
844 | if (ret) | |
845 | return ret; | |
846 | ||
6752e40d | 847 | tasklet_setup(&mdev->irq_tasklet, msgdma_tasklet); |
a85c6f1b SR |
848 | |
849 | dma_cookie_init(&mdev->dmachan); | |
850 | ||
851 | spin_lock_init(&mdev->lock); | |
852 | ||
853 | INIT_LIST_HEAD(&mdev->active_list); | |
854 | INIT_LIST_HEAD(&mdev->pending_list); | |
855 | INIT_LIST_HEAD(&mdev->done_list); | |
856 | INIT_LIST_HEAD(&mdev->free_list); | |
857 | ||
858 | dma_dev = &mdev->dmadev; | |
859 | ||
860 | /* Set DMA capabilities */ | |
861 | dma_cap_zero(dma_dev->cap_mask); | |
862 | dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask); | |
a85c6f1b SR |
863 | dma_cap_set(DMA_SLAVE, dma_dev->cap_mask); |
864 | ||
865 | dma_dev->src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES); | |
866 | dma_dev->dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES); | |
867 | dma_dev->directions = BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM) | | |
868 | BIT(DMA_MEM_TO_MEM); | |
869 | dma_dev->residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR; | |
870 | ||
871 | /* Init DMA link list */ | |
872 | INIT_LIST_HEAD(&dma_dev->channels); | |
873 | ||
874 | /* Set base routines */ | |
875 | dma_dev->device_tx_status = dma_cookie_status; | |
876 | dma_dev->device_issue_pending = msgdma_issue_pending; | |
877 | dma_dev->dev = &pdev->dev; | |
878 | ||
879 | dma_dev->copy_align = DMAENGINE_ALIGN_4_BYTES; | |
880 | dma_dev->device_prep_dma_memcpy = msgdma_prep_memcpy; | |
a85c6f1b SR |
881 | dma_dev->device_prep_slave_sg = msgdma_prep_slave_sg; |
882 | dma_dev->device_config = msgdma_dma_config; | |
883 | ||
884 | dma_dev->device_alloc_chan_resources = msgdma_alloc_chan_resources; | |
885 | dma_dev->device_free_chan_resources = msgdma_free_chan_resources; | |
886 | ||
887 | mdev->dmachan.device = dma_dev; | |
888 | list_add_tail(&mdev->dmachan.device_node, &dma_dev->channels); | |
889 | ||
890 | /* Set DMA mask to 64 bits */ | |
891 | ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64)); | |
892 | if (ret) { | |
893 | dev_warn(&pdev->dev, "unable to set coherent mask to 64"); | |
894 | ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32)); | |
895 | if (ret) | |
896 | goto fail; | |
897 | } | |
898 | ||
899 | msgdma_reset(mdev); | |
900 | ||
901 | ret = dma_async_device_register(dma_dev); | |
902 | if (ret) | |
903 | goto fail; | |
904 | ||
65675842 OD |
905 | ret = of_dma_controller_register(pdev->dev.of_node, |
906 | of_dma_xlate_by_chan_id, dma_dev); | |
907 | if (ret == -EINVAL) | |
908 | dev_warn(&pdev->dev, "device was not probed from DT"); | |
909 | else if (ret && ret != -ENODEV) | |
910 | goto fail; | |
911 | ||
a85c6f1b SR |
912 | dev_notice(&pdev->dev, "Altera mSGDMA driver probe success\n"); |
913 | ||
914 | return 0; | |
915 | ||
916 | fail: | |
917 | msgdma_dev_remove(mdev); | |
918 | ||
919 | return ret; | |
920 | } | |
921 | ||
922 | /** | |
923 | * msgdma_dma_remove - Driver remove function | |
924 | * @pdev: Pointer to the platform_device structure | |
925 | * | |
926 | * Return: Always '0' | |
927 | */ | |
928 | static int msgdma_remove(struct platform_device *pdev) | |
929 | { | |
930 | struct msgdma_device *mdev = platform_get_drvdata(pdev); | |
931 | ||
65675842 OD |
932 | if (pdev->dev.of_node) |
933 | of_dma_controller_free(pdev->dev.of_node); | |
a85c6f1b SR |
934 | dma_async_device_unregister(&mdev->dmadev); |
935 | msgdma_dev_remove(mdev); | |
936 | ||
937 | dev_notice(&pdev->dev, "Altera mSGDMA driver removed\n"); | |
938 | ||
939 | return 0; | |
940 | } | |
941 | ||
65675842 OD |
942 | #ifdef CONFIG_OF |
943 | static const struct of_device_id msgdma_match[] = { | |
944 | { .compatible = "altr,socfpga-msgdma", }, | |
945 | { } | |
946 | }; | |
947 | ||
948 | MODULE_DEVICE_TABLE(of, msgdma_match); | |
949 | #endif | |
950 | ||
a85c6f1b SR |
951 | static struct platform_driver msgdma_driver = { |
952 | .driver = { | |
953 | .name = "altera-msgdma", | |
65675842 | 954 | .of_match_table = of_match_ptr(msgdma_match), |
a85c6f1b SR |
955 | }, |
956 | .probe = msgdma_probe, | |
957 | .remove = msgdma_remove, | |
958 | }; | |
959 | ||
960 | module_platform_driver(msgdma_driver); | |
961 | ||
962 | MODULE_ALIAS("platform:altera-msgdma"); | |
963 | MODULE_DESCRIPTION("Altera mSGDMA driver"); | |
964 | MODULE_AUTHOR("Stefan Roese <sr@denx.de>"); | |
965 | MODULE_LICENSE("GPL"); |