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d8b46839 CM |
1 | /* |
2 | * Driver for STM32 DMA controller | |
3 | * | |
4 | * Inspired by dma-jz4740.c and tegra20-apb-dma.c | |
5 | * | |
6 | * Copyright (C) M'boumba Cedric Madianga 2015 | |
7 | * Author: M'boumba Cedric Madianga <cedric.madianga@gmail.com> | |
8 | * | |
9 | * License terms: GNU General Public License (GPL), version 2 | |
10 | */ | |
11 | ||
12 | #include <linux/clk.h> | |
13 | #include <linux/delay.h> | |
14 | #include <linux/dmaengine.h> | |
15 | #include <linux/dma-mapping.h> | |
16 | #include <linux/err.h> | |
17 | #include <linux/init.h> | |
18 | #include <linux/jiffies.h> | |
19 | #include <linux/list.h> | |
20 | #include <linux/module.h> | |
21 | #include <linux/of.h> | |
22 | #include <linux/of_device.h> | |
23 | #include <linux/of_dma.h> | |
24 | #include <linux/platform_device.h> | |
25 | #include <linux/reset.h> | |
26 | #include <linux/sched.h> | |
27 | #include <linux/slab.h> | |
28 | ||
29 | #include "virt-dma.h" | |
30 | ||
31 | #define STM32_DMA_LISR 0x0000 /* DMA Low Int Status Reg */ | |
32 | #define STM32_DMA_HISR 0x0004 /* DMA High Int Status Reg */ | |
33 | #define STM32_DMA_LIFCR 0x0008 /* DMA Low Int Flag Clear Reg */ | |
34 | #define STM32_DMA_HIFCR 0x000c /* DMA High Int Flag Clear Reg */ | |
35 | #define STM32_DMA_TCI BIT(5) /* Transfer Complete Interrupt */ | |
36 | #define STM32_DMA_TEI BIT(3) /* Transfer Error Interrupt */ | |
37 | #define STM32_DMA_DMEI BIT(2) /* Direct Mode Error Interrupt */ | |
38 | #define STM32_DMA_FEI BIT(0) /* FIFO Error Interrupt */ | |
39 | ||
40 | /* DMA Stream x Configuration Register */ | |
41 | #define STM32_DMA_SCR(x) (0x0010 + 0x18 * (x)) /* x = 0..7 */ | |
42 | #define STM32_DMA_SCR_REQ(n) ((n & 0x7) << 25) | |
43 | #define STM32_DMA_SCR_MBURST_MASK GENMASK(24, 23) | |
44 | #define STM32_DMA_SCR_MBURST(n) ((n & 0x3) << 23) | |
45 | #define STM32_DMA_SCR_PBURST_MASK GENMASK(22, 21) | |
46 | #define STM32_DMA_SCR_PBURST(n) ((n & 0x3) << 21) | |
47 | #define STM32_DMA_SCR_PL_MASK GENMASK(17, 16) | |
48 | #define STM32_DMA_SCR_PL(n) ((n & 0x3) << 16) | |
49 | #define STM32_DMA_SCR_MSIZE_MASK GENMASK(14, 13) | |
50 | #define STM32_DMA_SCR_MSIZE(n) ((n & 0x3) << 13) | |
51 | #define STM32_DMA_SCR_PSIZE_MASK GENMASK(12, 11) | |
52 | #define STM32_DMA_SCR_PSIZE(n) ((n & 0x3) << 11) | |
53 | #define STM32_DMA_SCR_PSIZE_GET(n) ((n & STM32_DMA_SCR_PSIZE_MASK) >> 11) | |
54 | #define STM32_DMA_SCR_DIR_MASK GENMASK(7, 6) | |
55 | #define STM32_DMA_SCR_DIR(n) ((n & 0x3) << 6) | |
56 | #define STM32_DMA_SCR_CT BIT(19) /* Target in double buffer */ | |
57 | #define STM32_DMA_SCR_DBM BIT(18) /* Double Buffer Mode */ | |
58 | #define STM32_DMA_SCR_PINCOS BIT(15) /* Peripheral inc offset size */ | |
59 | #define STM32_DMA_SCR_MINC BIT(10) /* Memory increment mode */ | |
60 | #define STM32_DMA_SCR_PINC BIT(9) /* Peripheral increment mode */ | |
61 | #define STM32_DMA_SCR_CIRC BIT(8) /* Circular mode */ | |
62 | #define STM32_DMA_SCR_PFCTRL BIT(5) /* Peripheral Flow Controller */ | |
63 | #define STM32_DMA_SCR_TCIE BIT(4) /* Transfer Cplete Int Enable*/ | |
64 | #define STM32_DMA_SCR_TEIE BIT(2) /* Transfer Error Int Enable */ | |
65 | #define STM32_DMA_SCR_DMEIE BIT(1) /* Direct Mode Err Int Enable */ | |
66 | #define STM32_DMA_SCR_EN BIT(0) /* Stream Enable */ | |
67 | #define STM32_DMA_SCR_CFG_MASK (STM32_DMA_SCR_PINC \ | |
68 | | STM32_DMA_SCR_MINC \ | |
69 | | STM32_DMA_SCR_PINCOS \ | |
70 | | STM32_DMA_SCR_PL_MASK) | |
71 | #define STM32_DMA_SCR_IRQ_MASK (STM32_DMA_SCR_TCIE \ | |
72 | | STM32_DMA_SCR_TEIE \ | |
73 | | STM32_DMA_SCR_DMEIE) | |
74 | ||
75 | /* DMA Stream x number of data register */ | |
76 | #define STM32_DMA_SNDTR(x) (0x0014 + 0x18 * (x)) | |
77 | ||
78 | /* DMA stream peripheral address register */ | |
79 | #define STM32_DMA_SPAR(x) (0x0018 + 0x18 * (x)) | |
80 | ||
81 | /* DMA stream x memory 0 address register */ | |
82 | #define STM32_DMA_SM0AR(x) (0x001c + 0x18 * (x)) | |
83 | ||
84 | /* DMA stream x memory 1 address register */ | |
85 | #define STM32_DMA_SM1AR(x) (0x0020 + 0x18 * (x)) | |
86 | ||
87 | /* DMA stream x FIFO control register */ | |
88 | #define STM32_DMA_SFCR(x) (0x0024 + 0x18 * (x)) | |
89 | #define STM32_DMA_SFCR_FTH_MASK GENMASK(1, 0) | |
90 | #define STM32_DMA_SFCR_FTH(n) (n & STM32_DMA_SFCR_FTH_MASK) | |
91 | #define STM32_DMA_SFCR_FEIE BIT(7) /* FIFO error interrupt enable */ | |
92 | #define STM32_DMA_SFCR_DMDIS BIT(2) /* Direct mode disable */ | |
93 | #define STM32_DMA_SFCR_MASK (STM32_DMA_SFCR_FEIE \ | |
94 | | STM32_DMA_SFCR_DMDIS) | |
95 | ||
96 | /* DMA direction */ | |
97 | #define STM32_DMA_DEV_TO_MEM 0x00 | |
98 | #define STM32_DMA_MEM_TO_DEV 0x01 | |
99 | #define STM32_DMA_MEM_TO_MEM 0x02 | |
100 | ||
101 | /* DMA priority level */ | |
102 | #define STM32_DMA_PRIORITY_LOW 0x00 | |
103 | #define STM32_DMA_PRIORITY_MEDIUM 0x01 | |
104 | #define STM32_DMA_PRIORITY_HIGH 0x02 | |
105 | #define STM32_DMA_PRIORITY_VERY_HIGH 0x03 | |
106 | ||
107 | /* DMA FIFO threshold selection */ | |
108 | #define STM32_DMA_FIFO_THRESHOLD_1QUARTERFULL 0x00 | |
109 | #define STM32_DMA_FIFO_THRESHOLD_HALFFULL 0x01 | |
110 | #define STM32_DMA_FIFO_THRESHOLD_3QUARTERSFULL 0x02 | |
111 | #define STM32_DMA_FIFO_THRESHOLD_FULL 0x03 | |
112 | ||
113 | #define STM32_DMA_MAX_DATA_ITEMS 0xffff | |
114 | #define STM32_DMA_MAX_CHANNELS 0x08 | |
115 | #define STM32_DMA_MAX_REQUEST_ID 0x08 | |
116 | #define STM32_DMA_MAX_DATA_PARAM 0x03 | |
117 | ||
118 | enum stm32_dma_width { | |
119 | STM32_DMA_BYTE, | |
120 | STM32_DMA_HALF_WORD, | |
121 | STM32_DMA_WORD, | |
122 | }; | |
123 | ||
124 | enum stm32_dma_burst_size { | |
125 | STM32_DMA_BURST_SINGLE, | |
126 | STM32_DMA_BURST_INCR4, | |
127 | STM32_DMA_BURST_INCR8, | |
128 | STM32_DMA_BURST_INCR16, | |
129 | }; | |
130 | ||
131 | struct stm32_dma_cfg { | |
132 | u32 channel_id; | |
133 | u32 request_line; | |
134 | u32 stream_config; | |
135 | u32 threshold; | |
136 | }; | |
137 | ||
138 | struct stm32_dma_chan_reg { | |
139 | u32 dma_lisr; | |
140 | u32 dma_hisr; | |
141 | u32 dma_lifcr; | |
142 | u32 dma_hifcr; | |
143 | u32 dma_scr; | |
144 | u32 dma_sndtr; | |
145 | u32 dma_spar; | |
146 | u32 dma_sm0ar; | |
147 | u32 dma_sm1ar; | |
148 | u32 dma_sfcr; | |
149 | }; | |
150 | ||
151 | struct stm32_dma_sg_req { | |
152 | u32 len; | |
153 | struct stm32_dma_chan_reg chan_reg; | |
154 | }; | |
155 | ||
156 | struct stm32_dma_desc { | |
157 | struct virt_dma_desc vdesc; | |
158 | bool cyclic; | |
159 | u32 num_sgs; | |
160 | struct stm32_dma_sg_req sg_req[]; | |
161 | }; | |
162 | ||
163 | struct stm32_dma_chan { | |
164 | struct virt_dma_chan vchan; | |
165 | bool config_init; | |
166 | bool busy; | |
167 | u32 id; | |
168 | u32 irq; | |
169 | struct stm32_dma_desc *desc; | |
170 | u32 next_sg; | |
171 | struct dma_slave_config dma_sconfig; | |
172 | struct stm32_dma_chan_reg chan_reg; | |
173 | }; | |
174 | ||
175 | struct stm32_dma_device { | |
176 | struct dma_device ddev; | |
177 | void __iomem *base; | |
178 | struct clk *clk; | |
179 | struct reset_control *rst; | |
180 | bool mem2mem; | |
181 | struct stm32_dma_chan chan[STM32_DMA_MAX_CHANNELS]; | |
182 | }; | |
183 | ||
184 | static struct stm32_dma_device *stm32_dma_get_dev(struct stm32_dma_chan *chan) | |
185 | { | |
186 | return container_of(chan->vchan.chan.device, struct stm32_dma_device, | |
187 | ddev); | |
188 | } | |
189 | ||
190 | static struct stm32_dma_chan *to_stm32_dma_chan(struct dma_chan *c) | |
191 | { | |
192 | return container_of(c, struct stm32_dma_chan, vchan.chan); | |
193 | } | |
194 | ||
195 | static struct stm32_dma_desc *to_stm32_dma_desc(struct virt_dma_desc *vdesc) | |
196 | { | |
197 | return container_of(vdesc, struct stm32_dma_desc, vdesc); | |
198 | } | |
199 | ||
200 | static struct device *chan2dev(struct stm32_dma_chan *chan) | |
201 | { | |
202 | return &chan->vchan.chan.dev->device; | |
203 | } | |
204 | ||
205 | static u32 stm32_dma_read(struct stm32_dma_device *dmadev, u32 reg) | |
206 | { | |
207 | return readl_relaxed(dmadev->base + reg); | |
208 | } | |
209 | ||
210 | static void stm32_dma_write(struct stm32_dma_device *dmadev, u32 reg, u32 val) | |
211 | { | |
212 | writel_relaxed(val, dmadev->base + reg); | |
213 | } | |
214 | ||
215 | static struct stm32_dma_desc *stm32_dma_alloc_desc(u32 num_sgs) | |
216 | { | |
217 | return kzalloc(sizeof(struct stm32_dma_desc) + | |
218 | sizeof(struct stm32_dma_sg_req) * num_sgs, GFP_NOWAIT); | |
219 | } | |
220 | ||
221 | static int stm32_dma_get_width(struct stm32_dma_chan *chan, | |
222 | enum dma_slave_buswidth width) | |
223 | { | |
224 | switch (width) { | |
225 | case DMA_SLAVE_BUSWIDTH_1_BYTE: | |
226 | return STM32_DMA_BYTE; | |
227 | case DMA_SLAVE_BUSWIDTH_2_BYTES: | |
228 | return STM32_DMA_HALF_WORD; | |
229 | case DMA_SLAVE_BUSWIDTH_4_BYTES: | |
230 | return STM32_DMA_WORD; | |
231 | default: | |
232 | dev_err(chan2dev(chan), "Dma bus width not supported\n"); | |
233 | return -EINVAL; | |
234 | } | |
235 | } | |
236 | ||
237 | static int stm32_dma_get_burst(struct stm32_dma_chan *chan, u32 maxburst) | |
238 | { | |
239 | switch (maxburst) { | |
240 | case 0: | |
241 | case 1: | |
242 | return STM32_DMA_BURST_SINGLE; | |
243 | case 4: | |
244 | return STM32_DMA_BURST_INCR4; | |
245 | case 8: | |
246 | return STM32_DMA_BURST_INCR8; | |
247 | case 16: | |
248 | return STM32_DMA_BURST_INCR16; | |
249 | default: | |
250 | dev_err(chan2dev(chan), "Dma burst size not supported\n"); | |
251 | return -EINVAL; | |
252 | } | |
253 | } | |
254 | ||
255 | static void stm32_dma_set_fifo_config(struct stm32_dma_chan *chan, | |
256 | u32 src_maxburst, u32 dst_maxburst) | |
257 | { | |
258 | chan->chan_reg.dma_sfcr &= ~STM32_DMA_SFCR_MASK; | |
259 | chan->chan_reg.dma_scr &= ~STM32_DMA_SCR_DMEIE; | |
260 | ||
261 | if ((!src_maxburst) && (!dst_maxburst)) { | |
262 | /* Using direct mode */ | |
263 | chan->chan_reg.dma_scr |= STM32_DMA_SCR_DMEIE; | |
264 | } else { | |
265 | /* Using FIFO mode */ | |
266 | chan->chan_reg.dma_sfcr |= STM32_DMA_SFCR_MASK; | |
267 | } | |
268 | } | |
269 | ||
270 | static int stm32_dma_slave_config(struct dma_chan *c, | |
271 | struct dma_slave_config *config) | |
272 | { | |
273 | struct stm32_dma_chan *chan = to_stm32_dma_chan(c); | |
274 | ||
275 | memcpy(&chan->dma_sconfig, config, sizeof(*config)); | |
276 | ||
277 | chan->config_init = true; | |
278 | ||
279 | return 0; | |
280 | } | |
281 | ||
282 | static u32 stm32_dma_irq_status(struct stm32_dma_chan *chan) | |
283 | { | |
284 | struct stm32_dma_device *dmadev = stm32_dma_get_dev(chan); | |
285 | u32 flags, dma_isr; | |
286 | ||
287 | /* | |
288 | * Read "flags" from DMA_xISR register corresponding to the selected | |
289 | * DMA channel at the correct bit offset inside that register. | |
290 | * | |
291 | * If (ch % 4) is 2 or 3, left shift the mask by 16 bits. | |
292 | * If (ch % 4) is 1 or 3, additionally left shift the mask by 6 bits. | |
293 | */ | |
294 | ||
295 | if (chan->id & 4) | |
296 | dma_isr = stm32_dma_read(dmadev, STM32_DMA_HISR); | |
297 | else | |
298 | dma_isr = stm32_dma_read(dmadev, STM32_DMA_LISR); | |
299 | ||
300 | flags = dma_isr >> (((chan->id & 2) << 3) | ((chan->id & 1) * 6)); | |
301 | ||
302 | return flags; | |
303 | } | |
304 | ||
305 | static void stm32_dma_irq_clear(struct stm32_dma_chan *chan, u32 flags) | |
306 | { | |
307 | struct stm32_dma_device *dmadev = stm32_dma_get_dev(chan); | |
308 | u32 dma_ifcr; | |
309 | ||
310 | /* | |
311 | * Write "flags" to the DMA_xIFCR register corresponding to the selected | |
312 | * DMA channel at the correct bit offset inside that register. | |
313 | * | |
314 | * If (ch % 4) is 2 or 3, left shift the mask by 16 bits. | |
315 | * If (ch % 4) is 1 or 3, additionally left shift the mask by 6 bits. | |
316 | */ | |
317 | dma_ifcr = flags << (((chan->id & 2) << 3) | ((chan->id & 1) * 6)); | |
318 | ||
319 | if (chan->id & 4) | |
320 | stm32_dma_write(dmadev, STM32_DMA_HIFCR, dma_ifcr); | |
321 | else | |
322 | stm32_dma_write(dmadev, STM32_DMA_LIFCR, dma_ifcr); | |
323 | } | |
324 | ||
325 | static int stm32_dma_disable_chan(struct stm32_dma_chan *chan) | |
326 | { | |
327 | struct stm32_dma_device *dmadev = stm32_dma_get_dev(chan); | |
328 | unsigned long timeout = jiffies + msecs_to_jiffies(5000); | |
329 | u32 dma_scr, id; | |
330 | ||
331 | id = chan->id; | |
332 | dma_scr = stm32_dma_read(dmadev, STM32_DMA_SCR(id)); | |
333 | ||
334 | if (dma_scr & STM32_DMA_SCR_EN) { | |
335 | dma_scr &= ~STM32_DMA_SCR_EN; | |
336 | stm32_dma_write(dmadev, STM32_DMA_SCR(id), dma_scr); | |
337 | ||
338 | do { | |
339 | dma_scr = stm32_dma_read(dmadev, STM32_DMA_SCR(id)); | |
340 | dma_scr &= STM32_DMA_SCR_EN; | |
341 | if (!dma_scr) | |
342 | break; | |
343 | ||
344 | if (time_after_eq(jiffies, timeout)) { | |
345 | dev_err(chan2dev(chan), "%s: timeout!\n", | |
346 | __func__); | |
347 | return -EBUSY; | |
348 | } | |
349 | cond_resched(); | |
350 | } while (1); | |
351 | } | |
352 | ||
353 | return 0; | |
354 | } | |
355 | ||
356 | static void stm32_dma_stop(struct stm32_dma_chan *chan) | |
357 | { | |
358 | struct stm32_dma_device *dmadev = stm32_dma_get_dev(chan); | |
359 | u32 dma_scr, dma_sfcr, status; | |
360 | int ret; | |
361 | ||
362 | /* Disable interrupts */ | |
363 | dma_scr = stm32_dma_read(dmadev, STM32_DMA_SCR(chan->id)); | |
364 | dma_scr &= ~STM32_DMA_SCR_IRQ_MASK; | |
365 | stm32_dma_write(dmadev, STM32_DMA_SCR(chan->id), dma_scr); | |
366 | dma_sfcr = stm32_dma_read(dmadev, STM32_DMA_SFCR(chan->id)); | |
367 | dma_sfcr &= ~STM32_DMA_SFCR_FEIE; | |
368 | stm32_dma_write(dmadev, STM32_DMA_SFCR(chan->id), dma_sfcr); | |
369 | ||
370 | /* Disable DMA */ | |
371 | ret = stm32_dma_disable_chan(chan); | |
372 | if (ret < 0) | |
373 | return; | |
374 | ||
375 | /* Clear interrupt status if it is there */ | |
376 | status = stm32_dma_irq_status(chan); | |
377 | if (status) { | |
378 | dev_dbg(chan2dev(chan), "%s(): clearing interrupt: 0x%08x\n", | |
379 | __func__, status); | |
380 | stm32_dma_irq_clear(chan, status); | |
381 | } | |
382 | ||
383 | chan->busy = false; | |
384 | } | |
385 | ||
386 | static int stm32_dma_terminate_all(struct dma_chan *c) | |
387 | { | |
388 | struct stm32_dma_chan *chan = to_stm32_dma_chan(c); | |
389 | unsigned long flags; | |
390 | LIST_HEAD(head); | |
391 | ||
392 | spin_lock_irqsave(&chan->vchan.lock, flags); | |
393 | ||
394 | if (chan->busy) { | |
395 | stm32_dma_stop(chan); | |
396 | chan->desc = NULL; | |
397 | } | |
398 | ||
399 | vchan_get_all_descriptors(&chan->vchan, &head); | |
400 | spin_unlock_irqrestore(&chan->vchan.lock, flags); | |
401 | vchan_dma_desc_free_list(&chan->vchan, &head); | |
402 | ||
403 | return 0; | |
404 | } | |
405 | ||
406 | static void stm32_dma_dump_reg(struct stm32_dma_chan *chan) | |
407 | { | |
408 | struct stm32_dma_device *dmadev = stm32_dma_get_dev(chan); | |
409 | u32 scr = stm32_dma_read(dmadev, STM32_DMA_SCR(chan->id)); | |
410 | u32 ndtr = stm32_dma_read(dmadev, STM32_DMA_SNDTR(chan->id)); | |
411 | u32 spar = stm32_dma_read(dmadev, STM32_DMA_SPAR(chan->id)); | |
412 | u32 sm0ar = stm32_dma_read(dmadev, STM32_DMA_SM0AR(chan->id)); | |
413 | u32 sm1ar = stm32_dma_read(dmadev, STM32_DMA_SM1AR(chan->id)); | |
414 | u32 sfcr = stm32_dma_read(dmadev, STM32_DMA_SFCR(chan->id)); | |
415 | ||
416 | dev_dbg(chan2dev(chan), "SCR: 0x%08x\n", scr); | |
417 | dev_dbg(chan2dev(chan), "NDTR: 0x%08x\n", ndtr); | |
418 | dev_dbg(chan2dev(chan), "SPAR: 0x%08x\n", spar); | |
419 | dev_dbg(chan2dev(chan), "SM0AR: 0x%08x\n", sm0ar); | |
420 | dev_dbg(chan2dev(chan), "SM1AR: 0x%08x\n", sm1ar); | |
421 | dev_dbg(chan2dev(chan), "SFCR: 0x%08x\n", sfcr); | |
422 | } | |
423 | ||
424 | static int stm32_dma_start_transfer(struct stm32_dma_chan *chan) | |
425 | { | |
426 | struct stm32_dma_device *dmadev = stm32_dma_get_dev(chan); | |
427 | struct virt_dma_desc *vdesc; | |
428 | struct stm32_dma_sg_req *sg_req; | |
429 | struct stm32_dma_chan_reg *reg; | |
430 | u32 status; | |
431 | int ret; | |
432 | ||
433 | ret = stm32_dma_disable_chan(chan); | |
434 | if (ret < 0) | |
435 | return ret; | |
436 | ||
437 | if (!chan->desc) { | |
438 | vdesc = vchan_next_desc(&chan->vchan); | |
439 | if (!vdesc) | |
aea08a5d | 440 | return -EPERM; |
d8b46839 CM |
441 | |
442 | chan->desc = to_stm32_dma_desc(vdesc); | |
443 | chan->next_sg = 0; | |
444 | } | |
445 | ||
446 | if (chan->next_sg == chan->desc->num_sgs) | |
447 | chan->next_sg = 0; | |
448 | ||
449 | sg_req = &chan->desc->sg_req[chan->next_sg]; | |
450 | reg = &sg_req->chan_reg; | |
451 | ||
452 | stm32_dma_write(dmadev, STM32_DMA_SCR(chan->id), reg->dma_scr); | |
453 | stm32_dma_write(dmadev, STM32_DMA_SPAR(chan->id), reg->dma_spar); | |
454 | stm32_dma_write(dmadev, STM32_DMA_SM0AR(chan->id), reg->dma_sm0ar); | |
455 | stm32_dma_write(dmadev, STM32_DMA_SFCR(chan->id), reg->dma_sfcr); | |
456 | stm32_dma_write(dmadev, STM32_DMA_SM1AR(chan->id), reg->dma_sm1ar); | |
457 | stm32_dma_write(dmadev, STM32_DMA_SNDTR(chan->id), reg->dma_sndtr); | |
458 | ||
459 | chan->next_sg++; | |
460 | ||
461 | /* Clear interrupt status if it is there */ | |
462 | status = stm32_dma_irq_status(chan); | |
463 | if (status) | |
464 | stm32_dma_irq_clear(chan, status); | |
465 | ||
466 | stm32_dma_dump_reg(chan); | |
467 | ||
468 | /* Start DMA */ | |
469 | reg->dma_scr |= STM32_DMA_SCR_EN; | |
470 | stm32_dma_write(dmadev, STM32_DMA_SCR(chan->id), reg->dma_scr); | |
471 | ||
472 | chan->busy = true; | |
473 | ||
474 | return 0; | |
475 | } | |
476 | ||
477 | static void stm32_dma_configure_next_sg(struct stm32_dma_chan *chan) | |
478 | { | |
479 | struct stm32_dma_device *dmadev = stm32_dma_get_dev(chan); | |
480 | struct stm32_dma_sg_req *sg_req; | |
481 | u32 dma_scr, dma_sm0ar, dma_sm1ar, id; | |
482 | ||
483 | id = chan->id; | |
484 | dma_scr = stm32_dma_read(dmadev, STM32_DMA_SCR(id)); | |
485 | ||
486 | if (dma_scr & STM32_DMA_SCR_DBM) { | |
487 | if (chan->next_sg == chan->desc->num_sgs) | |
488 | chan->next_sg = 0; | |
489 | ||
490 | sg_req = &chan->desc->sg_req[chan->next_sg]; | |
491 | ||
492 | if (dma_scr & STM32_DMA_SCR_CT) { | |
493 | dma_sm0ar = sg_req->chan_reg.dma_sm0ar; | |
494 | stm32_dma_write(dmadev, STM32_DMA_SM0AR(id), dma_sm0ar); | |
495 | dev_dbg(chan2dev(chan), "CT=1 <=> SM0AR: 0x%08x\n", | |
496 | stm32_dma_read(dmadev, STM32_DMA_SM0AR(id))); | |
497 | } else { | |
498 | dma_sm1ar = sg_req->chan_reg.dma_sm1ar; | |
499 | stm32_dma_write(dmadev, STM32_DMA_SM1AR(id), dma_sm1ar); | |
500 | dev_dbg(chan2dev(chan), "CT=0 <=> SM1AR: 0x%08x\n", | |
501 | stm32_dma_read(dmadev, STM32_DMA_SM1AR(id))); | |
502 | } | |
503 | ||
504 | chan->next_sg++; | |
505 | } | |
506 | } | |
507 | ||
508 | static void stm32_dma_handle_chan_done(struct stm32_dma_chan *chan) | |
509 | { | |
510 | if (chan->desc) { | |
511 | if (chan->desc->cyclic) { | |
512 | vchan_cyclic_callback(&chan->desc->vdesc); | |
513 | stm32_dma_configure_next_sg(chan); | |
514 | } else { | |
515 | chan->busy = false; | |
516 | if (chan->next_sg == chan->desc->num_sgs) { | |
517 | list_del(&chan->desc->vdesc.node); | |
518 | vchan_cookie_complete(&chan->desc->vdesc); | |
519 | chan->desc = NULL; | |
520 | } | |
521 | stm32_dma_start_transfer(chan); | |
522 | } | |
523 | } | |
524 | } | |
525 | ||
526 | static irqreturn_t stm32_dma_chan_irq(int irq, void *devid) | |
527 | { | |
528 | struct stm32_dma_chan *chan = devid; | |
529 | struct stm32_dma_device *dmadev = stm32_dma_get_dev(chan); | |
530 | u32 status, scr, sfcr; | |
531 | ||
532 | spin_lock(&chan->vchan.lock); | |
533 | ||
534 | status = stm32_dma_irq_status(chan); | |
535 | scr = stm32_dma_read(dmadev, STM32_DMA_SCR(chan->id)); | |
536 | sfcr = stm32_dma_read(dmadev, STM32_DMA_SFCR(chan->id)); | |
537 | ||
538 | if ((status & STM32_DMA_TCI) && (scr & STM32_DMA_SCR_TCIE)) { | |
539 | stm32_dma_irq_clear(chan, STM32_DMA_TCI); | |
540 | stm32_dma_handle_chan_done(chan); | |
541 | ||
542 | } else { | |
543 | stm32_dma_irq_clear(chan, status); | |
544 | dev_err(chan2dev(chan), "DMA error: status=0x%08x\n", status); | |
545 | } | |
546 | ||
547 | spin_unlock(&chan->vchan.lock); | |
548 | ||
549 | return IRQ_HANDLED; | |
550 | } | |
551 | ||
552 | static void stm32_dma_issue_pending(struct dma_chan *c) | |
553 | { | |
554 | struct stm32_dma_chan *chan = to_stm32_dma_chan(c); | |
555 | unsigned long flags; | |
556 | int ret; | |
557 | ||
558 | spin_lock_irqsave(&chan->vchan.lock, flags); | |
559 | if (!chan->busy) { | |
560 | if (vchan_issue_pending(&chan->vchan) && !chan->desc) { | |
561 | ret = stm32_dma_start_transfer(chan); | |
aea08a5d | 562 | if ((!ret) && (chan->desc->cyclic)) |
d8b46839 CM |
563 | stm32_dma_configure_next_sg(chan); |
564 | } | |
565 | } | |
566 | spin_unlock_irqrestore(&chan->vchan.lock, flags); | |
567 | } | |
568 | ||
569 | static int stm32_dma_set_xfer_param(struct stm32_dma_chan *chan, | |
570 | enum dma_transfer_direction direction, | |
571 | enum dma_slave_buswidth *buswidth) | |
572 | { | |
573 | enum dma_slave_buswidth src_addr_width, dst_addr_width; | |
574 | int src_bus_width, dst_bus_width; | |
575 | int src_burst_size, dst_burst_size; | |
576 | u32 src_maxburst, dst_maxburst; | |
577 | dma_addr_t src_addr, dst_addr; | |
578 | u32 dma_scr = 0; | |
579 | ||
580 | src_addr_width = chan->dma_sconfig.src_addr_width; | |
581 | dst_addr_width = chan->dma_sconfig.dst_addr_width; | |
582 | src_maxburst = chan->dma_sconfig.src_maxburst; | |
583 | dst_maxburst = chan->dma_sconfig.dst_maxburst; | |
584 | src_addr = chan->dma_sconfig.src_addr; | |
585 | dst_addr = chan->dma_sconfig.dst_addr; | |
586 | ||
587 | switch (direction) { | |
588 | case DMA_MEM_TO_DEV: | |
589 | dst_bus_width = stm32_dma_get_width(chan, dst_addr_width); | |
590 | if (dst_bus_width < 0) | |
591 | return dst_bus_width; | |
592 | ||
593 | dst_burst_size = stm32_dma_get_burst(chan, dst_maxburst); | |
594 | if (dst_burst_size < 0) | |
595 | return dst_burst_size; | |
596 | ||
597 | if (!src_addr_width) | |
598 | src_addr_width = dst_addr_width; | |
599 | ||
600 | src_bus_width = stm32_dma_get_width(chan, src_addr_width); | |
601 | if (src_bus_width < 0) | |
602 | return src_bus_width; | |
603 | ||
604 | src_burst_size = stm32_dma_get_burst(chan, src_maxburst); | |
605 | if (src_burst_size < 0) | |
606 | return src_burst_size; | |
607 | ||
608 | dma_scr = STM32_DMA_SCR_DIR(STM32_DMA_MEM_TO_DEV) | | |
609 | STM32_DMA_SCR_PSIZE(dst_bus_width) | | |
610 | STM32_DMA_SCR_MSIZE(src_bus_width) | | |
611 | STM32_DMA_SCR_PBURST(dst_burst_size) | | |
612 | STM32_DMA_SCR_MBURST(src_burst_size); | |
613 | ||
614 | chan->chan_reg.dma_spar = chan->dma_sconfig.dst_addr; | |
615 | *buswidth = dst_addr_width; | |
616 | break; | |
617 | ||
618 | case DMA_DEV_TO_MEM: | |
619 | src_bus_width = stm32_dma_get_width(chan, src_addr_width); | |
620 | if (src_bus_width < 0) | |
621 | return src_bus_width; | |
622 | ||
623 | src_burst_size = stm32_dma_get_burst(chan, src_maxburst); | |
624 | if (src_burst_size < 0) | |
625 | return src_burst_size; | |
626 | ||
627 | if (!dst_addr_width) | |
628 | dst_addr_width = src_addr_width; | |
629 | ||
630 | dst_bus_width = stm32_dma_get_width(chan, dst_addr_width); | |
631 | if (dst_bus_width < 0) | |
632 | return dst_bus_width; | |
633 | ||
634 | dst_burst_size = stm32_dma_get_burst(chan, dst_maxburst); | |
635 | if (dst_burst_size < 0) | |
636 | return dst_burst_size; | |
637 | ||
638 | dma_scr = STM32_DMA_SCR_DIR(STM32_DMA_DEV_TO_MEM) | | |
639 | STM32_DMA_SCR_PSIZE(src_bus_width) | | |
640 | STM32_DMA_SCR_MSIZE(dst_bus_width) | | |
641 | STM32_DMA_SCR_PBURST(src_burst_size) | | |
642 | STM32_DMA_SCR_MBURST(dst_burst_size); | |
643 | ||
644 | chan->chan_reg.dma_spar = chan->dma_sconfig.src_addr; | |
645 | *buswidth = chan->dma_sconfig.src_addr_width; | |
646 | break; | |
647 | ||
648 | default: | |
649 | dev_err(chan2dev(chan), "Dma direction is not supported\n"); | |
650 | return -EINVAL; | |
651 | } | |
652 | ||
653 | stm32_dma_set_fifo_config(chan, src_maxburst, dst_maxburst); | |
654 | ||
655 | chan->chan_reg.dma_scr &= ~(STM32_DMA_SCR_DIR_MASK | | |
656 | STM32_DMA_SCR_PSIZE_MASK | STM32_DMA_SCR_MSIZE_MASK | | |
657 | STM32_DMA_SCR_PBURST_MASK | STM32_DMA_SCR_MBURST_MASK); | |
658 | chan->chan_reg.dma_scr |= dma_scr; | |
659 | ||
660 | return 0; | |
661 | } | |
662 | ||
663 | static void stm32_dma_clear_reg(struct stm32_dma_chan_reg *regs) | |
664 | { | |
665 | memset(regs, 0, sizeof(struct stm32_dma_chan_reg)); | |
666 | } | |
667 | ||
668 | static struct dma_async_tx_descriptor *stm32_dma_prep_slave_sg( | |
669 | struct dma_chan *c, struct scatterlist *sgl, | |
670 | u32 sg_len, enum dma_transfer_direction direction, | |
671 | unsigned long flags, void *context) | |
672 | { | |
673 | struct stm32_dma_chan *chan = to_stm32_dma_chan(c); | |
674 | struct stm32_dma_desc *desc; | |
675 | struct scatterlist *sg; | |
676 | enum dma_slave_buswidth buswidth; | |
677 | u32 nb_data_items; | |
678 | int i, ret; | |
679 | ||
680 | if (!chan->config_init) { | |
681 | dev_err(chan2dev(chan), "dma channel is not configured\n"); | |
682 | return NULL; | |
683 | } | |
684 | ||
685 | if (sg_len < 1) { | |
686 | dev_err(chan2dev(chan), "Invalid segment length %d\n", sg_len); | |
687 | return NULL; | |
688 | } | |
689 | ||
690 | desc = stm32_dma_alloc_desc(sg_len); | |
691 | if (!desc) | |
692 | return NULL; | |
693 | ||
694 | ret = stm32_dma_set_xfer_param(chan, direction, &buswidth); | |
695 | if (ret < 0) | |
696 | goto err; | |
697 | ||
698 | /* Set peripheral flow controller */ | |
699 | if (chan->dma_sconfig.device_fc) | |
700 | chan->chan_reg.dma_scr |= STM32_DMA_SCR_PFCTRL; | |
701 | else | |
702 | chan->chan_reg.dma_scr &= ~STM32_DMA_SCR_PFCTRL; | |
703 | ||
704 | for_each_sg(sgl, sg, sg_len, i) { | |
705 | desc->sg_req[i].len = sg_dma_len(sg); | |
706 | ||
707 | nb_data_items = desc->sg_req[i].len / buswidth; | |
708 | if (nb_data_items > STM32_DMA_MAX_DATA_ITEMS) { | |
709 | dev_err(chan2dev(chan), "nb items not supported\n"); | |
710 | goto err; | |
711 | } | |
712 | ||
713 | stm32_dma_clear_reg(&desc->sg_req[i].chan_reg); | |
714 | desc->sg_req[i].chan_reg.dma_scr = chan->chan_reg.dma_scr; | |
715 | desc->sg_req[i].chan_reg.dma_sfcr = chan->chan_reg.dma_sfcr; | |
716 | desc->sg_req[i].chan_reg.dma_spar = chan->chan_reg.dma_spar; | |
717 | desc->sg_req[i].chan_reg.dma_sm0ar = sg_dma_address(sg); | |
718 | desc->sg_req[i].chan_reg.dma_sm1ar = sg_dma_address(sg); | |
719 | desc->sg_req[i].chan_reg.dma_sndtr = nb_data_items; | |
720 | } | |
721 | ||
722 | desc->num_sgs = sg_len; | |
723 | desc->cyclic = false; | |
724 | ||
725 | return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags); | |
726 | ||
727 | err: | |
728 | kfree(desc); | |
729 | return NULL; | |
730 | } | |
731 | ||
732 | static struct dma_async_tx_descriptor *stm32_dma_prep_dma_cyclic( | |
733 | struct dma_chan *c, dma_addr_t buf_addr, size_t buf_len, | |
734 | size_t period_len, enum dma_transfer_direction direction, | |
735 | unsigned long flags) | |
736 | { | |
737 | struct stm32_dma_chan *chan = to_stm32_dma_chan(c); | |
738 | struct stm32_dma_desc *desc; | |
739 | enum dma_slave_buswidth buswidth; | |
740 | u32 num_periods, nb_data_items; | |
741 | int i, ret; | |
742 | ||
743 | if (!buf_len || !period_len) { | |
744 | dev_err(chan2dev(chan), "Invalid buffer/period len\n"); | |
745 | return NULL; | |
746 | } | |
747 | ||
748 | if (!chan->config_init) { | |
749 | dev_err(chan2dev(chan), "dma channel is not configured\n"); | |
750 | return NULL; | |
751 | } | |
752 | ||
753 | if (buf_len % period_len) { | |
754 | dev_err(chan2dev(chan), "buf_len not multiple of period_len\n"); | |
755 | return NULL; | |
756 | } | |
757 | ||
758 | /* | |
759 | * We allow to take more number of requests till DMA is | |
760 | * not started. The driver will loop over all requests. | |
761 | * Once DMA is started then new requests can be queued only after | |
762 | * terminating the DMA. | |
763 | */ | |
764 | if (chan->busy) { | |
765 | dev_err(chan2dev(chan), "Request not allowed when dma busy\n"); | |
766 | return NULL; | |
767 | } | |
768 | ||
769 | ret = stm32_dma_set_xfer_param(chan, direction, &buswidth); | |
770 | if (ret < 0) | |
771 | return NULL; | |
772 | ||
773 | nb_data_items = period_len / buswidth; | |
774 | if (nb_data_items > STM32_DMA_MAX_DATA_ITEMS) { | |
775 | dev_err(chan2dev(chan), "number of items not supported\n"); | |
776 | return NULL; | |
777 | } | |
778 | ||
779 | /* Enable Circular mode or double buffer mode */ | |
780 | if (buf_len == period_len) | |
781 | chan->chan_reg.dma_scr |= STM32_DMA_SCR_CIRC; | |
782 | else | |
783 | chan->chan_reg.dma_scr |= STM32_DMA_SCR_DBM; | |
784 | ||
785 | /* Clear periph ctrl if client set it */ | |
786 | chan->chan_reg.dma_scr &= ~STM32_DMA_SCR_PFCTRL; | |
787 | ||
788 | num_periods = buf_len / period_len; | |
789 | ||
790 | desc = stm32_dma_alloc_desc(num_periods); | |
791 | if (!desc) | |
792 | return NULL; | |
793 | ||
794 | for (i = 0; i < num_periods; i++) { | |
795 | desc->sg_req[i].len = period_len; | |
796 | ||
797 | stm32_dma_clear_reg(&desc->sg_req[i].chan_reg); | |
798 | desc->sg_req[i].chan_reg.dma_scr = chan->chan_reg.dma_scr; | |
799 | desc->sg_req[i].chan_reg.dma_sfcr = chan->chan_reg.dma_sfcr; | |
800 | desc->sg_req[i].chan_reg.dma_spar = chan->chan_reg.dma_spar; | |
801 | desc->sg_req[i].chan_reg.dma_sm0ar = buf_addr; | |
802 | desc->sg_req[i].chan_reg.dma_sm1ar = buf_addr; | |
803 | desc->sg_req[i].chan_reg.dma_sndtr = nb_data_items; | |
804 | buf_addr += period_len; | |
805 | } | |
806 | ||
807 | desc->num_sgs = num_periods; | |
808 | desc->cyclic = true; | |
809 | ||
810 | return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags); | |
811 | } | |
812 | ||
813 | static struct dma_async_tx_descriptor *stm32_dma_prep_dma_memcpy( | |
814 | struct dma_chan *c, dma_addr_t dest, | |
815 | dma_addr_t src, size_t len, unsigned long flags) | |
816 | { | |
817 | struct stm32_dma_chan *chan = to_stm32_dma_chan(c); | |
818 | u32 num_sgs; | |
819 | struct stm32_dma_desc *desc; | |
820 | size_t xfer_count, offset; | |
821 | int i; | |
822 | ||
823 | num_sgs = DIV_ROUND_UP(len, STM32_DMA_MAX_DATA_ITEMS); | |
824 | desc = stm32_dma_alloc_desc(num_sgs); | |
825 | if (!desc) | |
826 | return NULL; | |
827 | ||
828 | for (offset = 0, i = 0; offset < len; offset += xfer_count, i++) { | |
829 | xfer_count = min_t(size_t, len - offset, | |
830 | STM32_DMA_MAX_DATA_ITEMS); | |
831 | ||
832 | desc->sg_req[i].len = xfer_count; | |
833 | ||
834 | stm32_dma_clear_reg(&desc->sg_req[i].chan_reg); | |
835 | desc->sg_req[i].chan_reg.dma_scr = | |
836 | STM32_DMA_SCR_DIR(STM32_DMA_MEM_TO_MEM) | | |
837 | STM32_DMA_SCR_MINC | | |
838 | STM32_DMA_SCR_PINC | | |
839 | STM32_DMA_SCR_TCIE | | |
840 | STM32_DMA_SCR_TEIE; | |
841 | desc->sg_req[i].chan_reg.dma_sfcr = STM32_DMA_SFCR_DMDIS | | |
842 | STM32_DMA_SFCR_FTH(STM32_DMA_FIFO_THRESHOLD_FULL) | | |
843 | STM32_DMA_SFCR_FEIE; | |
844 | desc->sg_req[i].chan_reg.dma_spar = src + offset; | |
845 | desc->sg_req[i].chan_reg.dma_sm0ar = dest + offset; | |
846 | desc->sg_req[i].chan_reg.dma_sndtr = xfer_count; | |
847 | } | |
848 | ||
849 | desc->num_sgs = num_sgs; | |
850 | desc->cyclic = false; | |
851 | ||
852 | return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags); | |
853 | } | |
854 | ||
855 | static size_t stm32_dma_desc_residue(struct stm32_dma_chan *chan, | |
856 | struct stm32_dma_desc *desc, | |
857 | u32 next_sg) | |
858 | { | |
859 | struct stm32_dma_device *dmadev = stm32_dma_get_dev(chan); | |
860 | u32 dma_scr, width, residue, count; | |
861 | int i; | |
862 | ||
863 | residue = 0; | |
864 | ||
865 | for (i = next_sg; i < desc->num_sgs; i++) | |
866 | residue += desc->sg_req[i].len; | |
867 | ||
868 | if (next_sg != 0) { | |
869 | dma_scr = stm32_dma_read(dmadev, STM32_DMA_SCR(chan->id)); | |
870 | width = STM32_DMA_SCR_PSIZE_GET(dma_scr); | |
871 | count = stm32_dma_read(dmadev, STM32_DMA_SNDTR(chan->id)); | |
872 | ||
873 | residue += count << width; | |
874 | } | |
875 | ||
876 | return residue; | |
877 | } | |
878 | ||
879 | static enum dma_status stm32_dma_tx_status(struct dma_chan *c, | |
880 | dma_cookie_t cookie, | |
881 | struct dma_tx_state *state) | |
882 | { | |
883 | struct stm32_dma_chan *chan = to_stm32_dma_chan(c); | |
884 | struct virt_dma_desc *vdesc; | |
885 | enum dma_status status; | |
886 | unsigned long flags; | |
887 | u32 residue; | |
888 | ||
889 | status = dma_cookie_status(c, cookie, state); | |
890 | if ((status == DMA_COMPLETE) || (!state)) | |
891 | return status; | |
892 | ||
893 | spin_lock_irqsave(&chan->vchan.lock, flags); | |
894 | vdesc = vchan_find_desc(&chan->vchan, cookie); | |
895 | if (cookie == chan->desc->vdesc.tx.cookie) { | |
896 | residue = stm32_dma_desc_residue(chan, chan->desc, | |
897 | chan->next_sg); | |
898 | } else if (vdesc) { | |
899 | residue = stm32_dma_desc_residue(chan, | |
900 | to_stm32_dma_desc(vdesc), 0); | |
901 | } else { | |
902 | residue = 0; | |
903 | } | |
904 | ||
905 | dma_set_residue(state, residue); | |
906 | ||
907 | spin_unlock_irqrestore(&chan->vchan.lock, flags); | |
908 | ||
909 | return status; | |
910 | } | |
911 | ||
912 | static int stm32_dma_alloc_chan_resources(struct dma_chan *c) | |
913 | { | |
914 | struct stm32_dma_chan *chan = to_stm32_dma_chan(c); | |
915 | struct stm32_dma_device *dmadev = stm32_dma_get_dev(chan); | |
916 | int ret; | |
917 | ||
918 | chan->config_init = false; | |
919 | ret = clk_prepare_enable(dmadev->clk); | |
920 | if (ret < 0) { | |
921 | dev_err(chan2dev(chan), "clk_prepare_enable failed: %d\n", ret); | |
922 | return ret; | |
923 | } | |
924 | ||
925 | ret = stm32_dma_disable_chan(chan); | |
926 | if (ret < 0) | |
927 | clk_disable_unprepare(dmadev->clk); | |
928 | ||
929 | return ret; | |
930 | } | |
931 | ||
932 | static void stm32_dma_free_chan_resources(struct dma_chan *c) | |
933 | { | |
934 | struct stm32_dma_chan *chan = to_stm32_dma_chan(c); | |
935 | struct stm32_dma_device *dmadev = stm32_dma_get_dev(chan); | |
936 | unsigned long flags; | |
937 | ||
938 | dev_dbg(chan2dev(chan), "Freeing channel %d\n", chan->id); | |
939 | ||
940 | if (chan->busy) { | |
941 | spin_lock_irqsave(&chan->vchan.lock, flags); | |
942 | stm32_dma_stop(chan); | |
943 | chan->desc = NULL; | |
944 | spin_unlock_irqrestore(&chan->vchan.lock, flags); | |
945 | } | |
946 | ||
947 | clk_disable_unprepare(dmadev->clk); | |
948 | ||
949 | vchan_free_chan_resources(to_virt_chan(c)); | |
950 | } | |
951 | ||
952 | static void stm32_dma_desc_free(struct virt_dma_desc *vdesc) | |
953 | { | |
954 | kfree(container_of(vdesc, struct stm32_dma_desc, vdesc)); | |
955 | } | |
956 | ||
957 | void stm32_dma_set_config(struct stm32_dma_chan *chan, | |
958 | struct stm32_dma_cfg *cfg) | |
959 | { | |
960 | stm32_dma_clear_reg(&chan->chan_reg); | |
961 | ||
962 | chan->chan_reg.dma_scr = cfg->stream_config & STM32_DMA_SCR_CFG_MASK; | |
963 | chan->chan_reg.dma_scr |= STM32_DMA_SCR_REQ(cfg->request_line); | |
964 | ||
965 | /* Enable Interrupts */ | |
966 | chan->chan_reg.dma_scr |= STM32_DMA_SCR_TEIE | STM32_DMA_SCR_TCIE; | |
967 | ||
968 | chan->chan_reg.dma_sfcr = cfg->threshold & STM32_DMA_SFCR_FTH_MASK; | |
969 | } | |
970 | ||
971 | static struct dma_chan *stm32_dma_of_xlate(struct of_phandle_args *dma_spec, | |
972 | struct of_dma *ofdma) | |
973 | { | |
974 | struct stm32_dma_device *dmadev = ofdma->of_dma_data; | |
975 | struct stm32_dma_cfg cfg; | |
976 | struct stm32_dma_chan *chan; | |
977 | struct dma_chan *c; | |
978 | ||
979 | if (dma_spec->args_count < 3) | |
980 | return NULL; | |
981 | ||
982 | cfg.channel_id = dma_spec->args[0]; | |
983 | cfg.request_line = dma_spec->args[1]; | |
984 | cfg.stream_config = dma_spec->args[2]; | |
985 | cfg.threshold = 0; | |
986 | ||
987 | if ((cfg.channel_id >= STM32_DMA_MAX_CHANNELS) || (cfg.request_line >= | |
988 | STM32_DMA_MAX_REQUEST_ID)) | |
989 | return NULL; | |
990 | ||
991 | if (dma_spec->args_count > 3) | |
992 | cfg.threshold = dma_spec->args[3]; | |
993 | ||
994 | chan = &dmadev->chan[cfg.channel_id]; | |
995 | ||
996 | c = dma_get_slave_channel(&chan->vchan.chan); | |
997 | if (c) | |
998 | stm32_dma_set_config(chan, &cfg); | |
999 | ||
1000 | return c; | |
1001 | } | |
1002 | ||
1003 | static const struct of_device_id stm32_dma_of_match[] = { | |
1004 | { .compatible = "st,stm32-dma", }, | |
1005 | { /* sentinel */ }, | |
1006 | }; | |
1007 | MODULE_DEVICE_TABLE(of, stm32_dma_of_match); | |
1008 | ||
1009 | static int stm32_dma_probe(struct platform_device *pdev) | |
1010 | { | |
1011 | struct stm32_dma_chan *chan; | |
1012 | struct stm32_dma_device *dmadev; | |
1013 | struct dma_device *dd; | |
1014 | const struct of_device_id *match; | |
1015 | struct resource *res; | |
1016 | int i, ret; | |
1017 | ||
1018 | match = of_match_device(stm32_dma_of_match, &pdev->dev); | |
1019 | if (!match) { | |
1020 | dev_err(&pdev->dev, "Error: No device match found\n"); | |
1021 | return -ENODEV; | |
1022 | } | |
1023 | ||
1024 | dmadev = devm_kzalloc(&pdev->dev, sizeof(*dmadev), GFP_KERNEL); | |
1025 | if (!dmadev) | |
1026 | return -ENOMEM; | |
1027 | ||
1028 | dd = &dmadev->ddev; | |
1029 | ||
1030 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
1031 | dmadev->base = devm_ioremap_resource(&pdev->dev, res); | |
1032 | if (IS_ERR(dmadev->base)) | |
1033 | return PTR_ERR(dmadev->base); | |
1034 | ||
1035 | dmadev->clk = devm_clk_get(&pdev->dev, NULL); | |
1036 | if (IS_ERR(dmadev->clk)) { | |
1037 | dev_err(&pdev->dev, "Error: Missing controller clock\n"); | |
1038 | return PTR_ERR(dmadev->clk); | |
1039 | } | |
1040 | ||
1041 | dmadev->mem2mem = of_property_read_bool(pdev->dev.of_node, | |
1042 | "st,mem2mem"); | |
1043 | ||
1044 | dmadev->rst = devm_reset_control_get(&pdev->dev, NULL); | |
1045 | if (!IS_ERR(dmadev->rst)) { | |
1046 | reset_control_assert(dmadev->rst); | |
1047 | udelay(2); | |
1048 | reset_control_deassert(dmadev->rst); | |
1049 | } | |
1050 | ||
1051 | dma_cap_set(DMA_SLAVE, dd->cap_mask); | |
1052 | dma_cap_set(DMA_PRIVATE, dd->cap_mask); | |
1053 | dma_cap_set(DMA_CYCLIC, dd->cap_mask); | |
1054 | dd->device_alloc_chan_resources = stm32_dma_alloc_chan_resources; | |
1055 | dd->device_free_chan_resources = stm32_dma_free_chan_resources; | |
1056 | dd->device_tx_status = stm32_dma_tx_status; | |
1057 | dd->device_issue_pending = stm32_dma_issue_pending; | |
1058 | dd->device_prep_slave_sg = stm32_dma_prep_slave_sg; | |
1059 | dd->device_prep_dma_cyclic = stm32_dma_prep_dma_cyclic; | |
1060 | dd->device_config = stm32_dma_slave_config; | |
1061 | dd->device_terminate_all = stm32_dma_terminate_all; | |
1062 | dd->src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | | |
1063 | BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | | |
1064 | BIT(DMA_SLAVE_BUSWIDTH_4_BYTES); | |
1065 | dd->dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | | |
1066 | BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | | |
1067 | BIT(DMA_SLAVE_BUSWIDTH_4_BYTES); | |
1068 | dd->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV); | |
1069 | dd->residue_granularity = DMA_RESIDUE_GRANULARITY_BURST; | |
1070 | dd->dev = &pdev->dev; | |
1071 | INIT_LIST_HEAD(&dd->channels); | |
1072 | ||
1073 | if (dmadev->mem2mem) { | |
1074 | dma_cap_set(DMA_MEMCPY, dd->cap_mask); | |
1075 | dd->device_prep_dma_memcpy = stm32_dma_prep_dma_memcpy; | |
1076 | dd->directions |= BIT(DMA_MEM_TO_MEM); | |
1077 | } | |
1078 | ||
1079 | for (i = 0; i < STM32_DMA_MAX_CHANNELS; i++) { | |
1080 | chan = &dmadev->chan[i]; | |
1081 | chan->id = i; | |
1082 | chan->vchan.desc_free = stm32_dma_desc_free; | |
1083 | vchan_init(&chan->vchan, dd); | |
1084 | } | |
1085 | ||
1086 | ret = dma_async_device_register(dd); | |
1087 | if (ret) | |
1088 | return ret; | |
1089 | ||
1090 | for (i = 0; i < STM32_DMA_MAX_CHANNELS; i++) { | |
1091 | chan = &dmadev->chan[i]; | |
1092 | res = platform_get_resource(pdev, IORESOURCE_IRQ, i); | |
1093 | if (!res) { | |
1094 | ret = -EINVAL; | |
1095 | dev_err(&pdev->dev, "No irq resource for chan %d\n", i); | |
1096 | goto err_unregister; | |
1097 | } | |
1098 | chan->irq = res->start; | |
1099 | ret = devm_request_irq(&pdev->dev, chan->irq, | |
1100 | stm32_dma_chan_irq, 0, | |
1101 | dev_name(chan2dev(chan)), chan); | |
1102 | if (ret) { | |
1103 | dev_err(&pdev->dev, | |
1104 | "request_irq failed with err %d channel %d\n", | |
1105 | ret, i); | |
1106 | goto err_unregister; | |
1107 | } | |
1108 | } | |
1109 | ||
1110 | ret = of_dma_controller_register(pdev->dev.of_node, | |
1111 | stm32_dma_of_xlate, dmadev); | |
1112 | if (ret < 0) { | |
1113 | dev_err(&pdev->dev, | |
1114 | "STM32 DMA DMA OF registration failed %d\n", ret); | |
1115 | goto err_unregister; | |
1116 | } | |
1117 | ||
1118 | platform_set_drvdata(pdev, dmadev); | |
1119 | ||
1120 | dev_info(&pdev->dev, "STM32 DMA driver registered\n"); | |
1121 | ||
1122 | return 0; | |
1123 | ||
1124 | err_unregister: | |
1125 | dma_async_device_unregister(dd); | |
1126 | ||
1127 | return ret; | |
1128 | } | |
1129 | ||
1130 | static struct platform_driver stm32_dma_driver = { | |
1131 | .driver = { | |
1132 | .name = "stm32-dma", | |
1133 | .of_match_table = stm32_dma_of_match, | |
1134 | }, | |
1135 | }; | |
1136 | ||
1137 | static int __init stm32_dma_init(void) | |
1138 | { | |
1139 | return platform_driver_probe(&stm32_dma_driver, stm32_dma_probe); | |
1140 | } | |
1141 | subsys_initcall(stm32_dma_init); |