Commit | Line | Data |
---|---|---|
d894fc60 AS |
1 | /* |
2 | * Ingenic JZ4780 DMA controller | |
3 | * | |
4 | * Copyright (c) 2015 Imagination Technologies | |
5 | * Author: Alex Smith <alex@alex-smith.me.uk> | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify it | |
8 | * under the terms of the GNU General Public License as published by the | |
9 | * Free Software Foundation; either version 2 of the License, or (at your | |
10 | * option) any later version. | |
11 | */ | |
12 | ||
13 | #include <linux/clk.h> | |
14 | #include <linux/dmapool.h> | |
15 | #include <linux/init.h> | |
16 | #include <linux/interrupt.h> | |
17 | #include <linux/module.h> | |
18 | #include <linux/of.h> | |
19 | #include <linux/of_dma.h> | |
20 | #include <linux/platform_device.h> | |
21 | #include <linux/slab.h> | |
22 | ||
23 | #include "dmaengine.h" | |
24 | #include "virt-dma.h" | |
25 | ||
26 | #define JZ_DMA_NR_CHANNELS 32 | |
27 | ||
28 | /* Global registers. */ | |
29 | #define JZ_DMA_REG_DMAC 0x1000 | |
30 | #define JZ_DMA_REG_DIRQP 0x1004 | |
31 | #define JZ_DMA_REG_DDR 0x1008 | |
32 | #define JZ_DMA_REG_DDRS 0x100c | |
33 | #define JZ_DMA_REG_DMACP 0x101c | |
34 | #define JZ_DMA_REG_DSIRQP 0x1020 | |
35 | #define JZ_DMA_REG_DSIRQM 0x1024 | |
36 | #define JZ_DMA_REG_DCIRQP 0x1028 | |
37 | #define JZ_DMA_REG_DCIRQM 0x102c | |
38 | ||
39 | /* Per-channel registers. */ | |
40 | #define JZ_DMA_REG_CHAN(n) (n * 0x20) | |
41 | #define JZ_DMA_REG_DSA(n) (0x00 + JZ_DMA_REG_CHAN(n)) | |
42 | #define JZ_DMA_REG_DTA(n) (0x04 + JZ_DMA_REG_CHAN(n)) | |
43 | #define JZ_DMA_REG_DTC(n) (0x08 + JZ_DMA_REG_CHAN(n)) | |
44 | #define JZ_DMA_REG_DRT(n) (0x0c + JZ_DMA_REG_CHAN(n)) | |
45 | #define JZ_DMA_REG_DCS(n) (0x10 + JZ_DMA_REG_CHAN(n)) | |
46 | #define JZ_DMA_REG_DCM(n) (0x14 + JZ_DMA_REG_CHAN(n)) | |
47 | #define JZ_DMA_REG_DDA(n) (0x18 + JZ_DMA_REG_CHAN(n)) | |
48 | #define JZ_DMA_REG_DSD(n) (0x1c + JZ_DMA_REG_CHAN(n)) | |
49 | ||
50 | #define JZ_DMA_DMAC_DMAE BIT(0) | |
51 | #define JZ_DMA_DMAC_AR BIT(2) | |
52 | #define JZ_DMA_DMAC_HLT BIT(3) | |
53 | #define JZ_DMA_DMAC_FMSC BIT(31) | |
54 | ||
55 | #define JZ_DMA_DRT_AUTO 0x8 | |
56 | ||
57 | #define JZ_DMA_DCS_CTE BIT(0) | |
58 | #define JZ_DMA_DCS_HLT BIT(2) | |
59 | #define JZ_DMA_DCS_TT BIT(3) | |
60 | #define JZ_DMA_DCS_AR BIT(4) | |
61 | #define JZ_DMA_DCS_DES8 BIT(30) | |
62 | ||
63 | #define JZ_DMA_DCM_LINK BIT(0) | |
64 | #define JZ_DMA_DCM_TIE BIT(1) | |
65 | #define JZ_DMA_DCM_STDE BIT(2) | |
66 | #define JZ_DMA_DCM_TSZ_SHIFT 8 | |
67 | #define JZ_DMA_DCM_TSZ_MASK (0x7 << JZ_DMA_DCM_TSZ_SHIFT) | |
68 | #define JZ_DMA_DCM_DP_SHIFT 12 | |
69 | #define JZ_DMA_DCM_SP_SHIFT 14 | |
70 | #define JZ_DMA_DCM_DAI BIT(22) | |
71 | #define JZ_DMA_DCM_SAI BIT(23) | |
72 | ||
73 | #define JZ_DMA_SIZE_4_BYTE 0x0 | |
74 | #define JZ_DMA_SIZE_1_BYTE 0x1 | |
75 | #define JZ_DMA_SIZE_2_BYTE 0x2 | |
76 | #define JZ_DMA_SIZE_16_BYTE 0x3 | |
77 | #define JZ_DMA_SIZE_32_BYTE 0x4 | |
78 | #define JZ_DMA_SIZE_64_BYTE 0x5 | |
79 | #define JZ_DMA_SIZE_128_BYTE 0x6 | |
80 | ||
81 | #define JZ_DMA_WIDTH_32_BIT 0x0 | |
82 | #define JZ_DMA_WIDTH_8_BIT 0x1 | |
83 | #define JZ_DMA_WIDTH_16_BIT 0x2 | |
84 | ||
85 | #define JZ_DMA_BUSWIDTHS (BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \ | |
86 | BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \ | |
87 | BIT(DMA_SLAVE_BUSWIDTH_4_BYTES)) | |
88 | ||
89 | /** | |
90 | * struct jz4780_dma_hwdesc - descriptor structure read by the DMA controller. | |
91 | * @dcm: value for the DCM (channel command) register | |
92 | * @dsa: source address | |
93 | * @dta: target address | |
94 | * @dtc: transfer count (number of blocks of the transfer size specified in DCM | |
95 | * to transfer) in the low 24 bits, offset of the next descriptor from the | |
96 | * descriptor base address in the upper 8 bits. | |
97 | * @sd: target/source stride difference (in stride transfer mode). | |
98 | * @drt: request type | |
99 | */ | |
100 | struct jz4780_dma_hwdesc { | |
101 | uint32_t dcm; | |
102 | uint32_t dsa; | |
103 | uint32_t dta; | |
104 | uint32_t dtc; | |
105 | uint32_t sd; | |
106 | uint32_t drt; | |
107 | uint32_t reserved[2]; | |
108 | }; | |
109 | ||
110 | /* Size of allocations for hardware descriptor blocks. */ | |
111 | #define JZ_DMA_DESC_BLOCK_SIZE PAGE_SIZE | |
112 | #define JZ_DMA_MAX_DESC \ | |
113 | (JZ_DMA_DESC_BLOCK_SIZE / sizeof(struct jz4780_dma_hwdesc)) | |
114 | ||
115 | struct jz4780_dma_desc { | |
116 | struct virt_dma_desc vdesc; | |
117 | ||
118 | struct jz4780_dma_hwdesc *desc; | |
119 | dma_addr_t desc_phys; | |
120 | unsigned int count; | |
121 | enum dma_transaction_type type; | |
122 | uint32_t status; | |
123 | }; | |
124 | ||
125 | struct jz4780_dma_chan { | |
126 | struct virt_dma_chan vchan; | |
127 | unsigned int id; | |
128 | struct dma_pool *desc_pool; | |
129 | ||
130 | uint32_t transfer_type; | |
131 | uint32_t transfer_shift; | |
132 | struct dma_slave_config config; | |
133 | ||
134 | struct jz4780_dma_desc *desc; | |
135 | unsigned int curr_hwdesc; | |
136 | }; | |
137 | ||
138 | struct jz4780_dma_dev { | |
139 | struct dma_device dma_device; | |
140 | void __iomem *base; | |
141 | struct clk *clk; | |
142 | unsigned int irq; | |
143 | ||
144 | uint32_t chan_reserved; | |
145 | struct jz4780_dma_chan chan[JZ_DMA_NR_CHANNELS]; | |
146 | }; | |
147 | ||
148 | struct jz4780_dma_data { | |
149 | uint32_t transfer_type; | |
150 | int channel; | |
151 | }; | |
152 | ||
153 | static inline struct jz4780_dma_chan *to_jz4780_dma_chan(struct dma_chan *chan) | |
154 | { | |
155 | return container_of(chan, struct jz4780_dma_chan, vchan.chan); | |
156 | } | |
157 | ||
158 | static inline struct jz4780_dma_desc *to_jz4780_dma_desc( | |
159 | struct virt_dma_desc *vdesc) | |
160 | { | |
161 | return container_of(vdesc, struct jz4780_dma_desc, vdesc); | |
162 | } | |
163 | ||
164 | static inline struct jz4780_dma_dev *jz4780_dma_chan_parent( | |
165 | struct jz4780_dma_chan *jzchan) | |
166 | { | |
167 | return container_of(jzchan->vchan.chan.device, struct jz4780_dma_dev, | |
168 | dma_device); | |
169 | } | |
170 | ||
171 | static inline uint32_t jz4780_dma_readl(struct jz4780_dma_dev *jzdma, | |
172 | unsigned int reg) | |
173 | { | |
174 | return readl(jzdma->base + reg); | |
175 | } | |
176 | ||
177 | static inline void jz4780_dma_writel(struct jz4780_dma_dev *jzdma, | |
178 | unsigned int reg, uint32_t val) | |
179 | { | |
180 | writel(val, jzdma->base + reg); | |
181 | } | |
182 | ||
183 | static struct jz4780_dma_desc *jz4780_dma_desc_alloc( | |
184 | struct jz4780_dma_chan *jzchan, unsigned int count, | |
185 | enum dma_transaction_type type) | |
186 | { | |
187 | struct jz4780_dma_desc *desc; | |
188 | ||
189 | if (count > JZ_DMA_MAX_DESC) | |
190 | return NULL; | |
191 | ||
192 | desc = kzalloc(sizeof(*desc), GFP_NOWAIT); | |
193 | if (!desc) | |
194 | return NULL; | |
195 | ||
196 | desc->desc = dma_pool_alloc(jzchan->desc_pool, GFP_NOWAIT, | |
197 | &desc->desc_phys); | |
198 | if (!desc->desc) { | |
199 | kfree(desc); | |
200 | return NULL; | |
201 | } | |
202 | ||
203 | desc->count = count; | |
204 | desc->type = type; | |
205 | return desc; | |
206 | } | |
207 | ||
208 | static void jz4780_dma_desc_free(struct virt_dma_desc *vdesc) | |
209 | { | |
210 | struct jz4780_dma_desc *desc = to_jz4780_dma_desc(vdesc); | |
211 | struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(vdesc->tx.chan); | |
212 | ||
213 | dma_pool_free(jzchan->desc_pool, desc->desc, desc->desc_phys); | |
214 | kfree(desc); | |
215 | } | |
216 | ||
217 | static uint32_t jz4780_dma_transfer_size(unsigned long val, int *ord) | |
218 | { | |
219 | *ord = ffs(val) - 1; | |
220 | ||
221 | switch (*ord) { | |
222 | case 0: | |
223 | return JZ_DMA_SIZE_1_BYTE; | |
224 | case 1: | |
225 | return JZ_DMA_SIZE_2_BYTE; | |
226 | case 2: | |
227 | return JZ_DMA_SIZE_4_BYTE; | |
228 | case 4: | |
229 | return JZ_DMA_SIZE_16_BYTE; | |
230 | case 5: | |
231 | return JZ_DMA_SIZE_32_BYTE; | |
232 | case 6: | |
233 | return JZ_DMA_SIZE_64_BYTE; | |
234 | case 7: | |
235 | return JZ_DMA_SIZE_128_BYTE; | |
236 | default: | |
237 | return -EINVAL; | |
238 | } | |
239 | } | |
240 | ||
241 | static uint32_t jz4780_dma_setup_hwdesc(struct jz4780_dma_chan *jzchan, | |
242 | struct jz4780_dma_hwdesc *desc, dma_addr_t addr, size_t len, | |
243 | enum dma_transfer_direction direction) | |
244 | { | |
245 | struct dma_slave_config *config = &jzchan->config; | |
246 | uint32_t width, maxburst, tsz; | |
247 | int ord; | |
248 | ||
249 | if (direction == DMA_MEM_TO_DEV) { | |
250 | desc->dcm = JZ_DMA_DCM_SAI; | |
251 | desc->dsa = addr; | |
252 | desc->dta = config->dst_addr; | |
253 | desc->drt = jzchan->transfer_type; | |
254 | ||
255 | width = config->dst_addr_width; | |
256 | maxburst = config->dst_maxburst; | |
257 | } else { | |
258 | desc->dcm = JZ_DMA_DCM_DAI; | |
259 | desc->dsa = config->src_addr; | |
260 | desc->dta = addr; | |
261 | desc->drt = jzchan->transfer_type; | |
262 | ||
263 | width = config->src_addr_width; | |
264 | maxburst = config->src_maxburst; | |
265 | } | |
266 | ||
267 | /* | |
268 | * This calculates the maximum transfer size that can be used with the | |
269 | * given address, length, width and maximum burst size. The address | |
270 | * must be aligned to the transfer size, the total length must be | |
271 | * divisible by the transfer size, and we must not use more than the | |
272 | * maximum burst specified by the user. | |
273 | */ | |
274 | tsz = jz4780_dma_transfer_size(addr | len | (width * maxburst), &ord); | |
275 | jzchan->transfer_shift = ord; | |
276 | ||
277 | switch (width) { | |
278 | case DMA_SLAVE_BUSWIDTH_1_BYTE: | |
279 | case DMA_SLAVE_BUSWIDTH_2_BYTES: | |
280 | break; | |
281 | case DMA_SLAVE_BUSWIDTH_4_BYTES: | |
282 | width = JZ_DMA_WIDTH_32_BIT; | |
283 | break; | |
284 | default: | |
285 | return -EINVAL; | |
286 | } | |
287 | ||
288 | desc->dcm |= tsz << JZ_DMA_DCM_TSZ_SHIFT; | |
289 | desc->dcm |= width << JZ_DMA_DCM_SP_SHIFT; | |
290 | desc->dcm |= width << JZ_DMA_DCM_DP_SHIFT; | |
291 | ||
292 | desc->dtc = len >> ord; | |
293 | } | |
294 | ||
295 | static struct dma_async_tx_descriptor *jz4780_dma_prep_slave_sg( | |
296 | struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len, | |
297 | enum dma_transfer_direction direction, unsigned long flags) | |
298 | { | |
299 | struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); | |
300 | struct jz4780_dma_desc *desc; | |
301 | unsigned int i; | |
302 | int err; | |
303 | ||
304 | desc = jz4780_dma_desc_alloc(jzchan, sg_len, DMA_SLAVE); | |
305 | if (!desc) | |
306 | return NULL; | |
307 | ||
308 | for (i = 0; i < sg_len; i++) { | |
309 | err = jz4780_dma_setup_hwdesc(jzchan, &desc->desc[i], | |
310 | sg_dma_address(&sgl[i]), | |
311 | sg_dma_len(&sgl[i]), | |
312 | direction); | |
313 | if (err < 0) | |
314 | return ERR_PTR(err); | |
315 | ||
316 | ||
317 | desc->desc[i].dcm |= JZ_DMA_DCM_TIE; | |
318 | ||
319 | if (i != (sg_len - 1)) { | |
320 | /* Automatically proceeed to the next descriptor. */ | |
321 | desc->desc[i].dcm |= JZ_DMA_DCM_LINK; | |
322 | ||
323 | /* | |
324 | * The upper 8 bits of the DTC field in the descriptor | |
325 | * must be set to (offset from descriptor base of next | |
326 | * descriptor >> 4). | |
327 | */ | |
328 | desc->desc[i].dtc |= | |
329 | (((i + 1) * sizeof(*desc->desc)) >> 4) << 24; | |
330 | } | |
331 | } | |
332 | ||
333 | return vchan_tx_prep(&jzchan->vchan, &desc->vdesc, flags); | |
334 | } | |
335 | ||
336 | static struct dma_async_tx_descriptor *jz4780_dma_prep_dma_cyclic( | |
337 | struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len, | |
338 | size_t period_len, enum dma_transfer_direction direction, | |
339 | unsigned long flags) | |
340 | { | |
341 | struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); | |
342 | struct jz4780_dma_desc *desc; | |
343 | unsigned int periods, i; | |
344 | int err; | |
345 | ||
346 | if (buf_len % period_len) | |
347 | return NULL; | |
348 | ||
349 | periods = buf_len / period_len; | |
350 | ||
351 | desc = jz4780_dma_desc_alloc(jzchan, periods, DMA_CYCLIC); | |
352 | if (!desc) | |
353 | return NULL; | |
354 | ||
355 | for (i = 0; i < periods; i++) { | |
356 | err = jz4780_dma_setup_hwdesc(jzchan, &desc->desc[i], buf_addr, | |
357 | period_len, direction); | |
358 | if (err < 0) | |
359 | return ERR_PTR(err); | |
360 | ||
361 | buf_addr += period_len; | |
362 | ||
363 | /* | |
364 | * Set the link bit to indicate that the controller should | |
365 | * automatically proceed to the next descriptor. In | |
366 | * jz4780_dma_begin(), this will be cleared if we need to issue | |
367 | * an interrupt after each period. | |
368 | */ | |
369 | desc->desc[i].dcm |= JZ_DMA_DCM_TIE | JZ_DMA_DCM_LINK; | |
370 | ||
371 | /* | |
372 | * The upper 8 bits of the DTC field in the descriptor must be | |
373 | * set to (offset from descriptor base of next descriptor >> 4). | |
374 | * If this is the last descriptor, link it back to the first, | |
375 | * i.e. leave offset set to 0, otherwise point to the next one. | |
376 | */ | |
377 | if (i != (periods - 1)) { | |
378 | desc->desc[i].dtc |= | |
379 | (((i + 1) * sizeof(*desc->desc)) >> 4) << 24; | |
380 | } | |
381 | } | |
382 | ||
383 | return vchan_tx_prep(&jzchan->vchan, &desc->vdesc, flags); | |
384 | } | |
385 | ||
386 | struct dma_async_tx_descriptor *jz4780_dma_prep_dma_memcpy( | |
387 | struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, | |
388 | size_t len, unsigned long flags) | |
389 | { | |
390 | struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); | |
391 | struct jz4780_dma_desc *desc; | |
392 | uint32_t tsz; | |
393 | int ord; | |
394 | ||
395 | desc = jz4780_dma_desc_alloc(jzchan, 1, DMA_MEMCPY); | |
396 | if (!desc) | |
397 | return NULL; | |
398 | ||
399 | tsz = jz4780_dma_transfer_size(dest | src | len, &ord); | |
400 | if (tsz < 0) | |
401 | return ERR_PTR(tsz); | |
402 | ||
403 | desc->desc[0].dsa = src; | |
404 | desc->desc[0].dta = dest; | |
405 | desc->desc[0].drt = JZ_DMA_DRT_AUTO; | |
406 | desc->desc[0].dcm = JZ_DMA_DCM_TIE | JZ_DMA_DCM_SAI | JZ_DMA_DCM_DAI | | |
407 | tsz << JZ_DMA_DCM_TSZ_SHIFT | | |
408 | JZ_DMA_WIDTH_32_BIT << JZ_DMA_DCM_SP_SHIFT | | |
409 | JZ_DMA_WIDTH_32_BIT << JZ_DMA_DCM_DP_SHIFT; | |
410 | desc->desc[0].dtc = len >> ord; | |
411 | ||
412 | return vchan_tx_prep(&jzchan->vchan, &desc->vdesc, flags); | |
413 | } | |
414 | ||
415 | static void jz4780_dma_begin(struct jz4780_dma_chan *jzchan) | |
416 | { | |
417 | struct jz4780_dma_dev *jzdma = jz4780_dma_chan_parent(jzchan); | |
418 | struct virt_dma_desc *vdesc; | |
419 | unsigned int i; | |
420 | dma_addr_t desc_phys; | |
421 | ||
422 | if (!jzchan->desc) { | |
423 | vdesc = vchan_next_desc(&jzchan->vchan); | |
424 | if (!vdesc) | |
425 | return; | |
426 | ||
427 | list_del(&vdesc->node); | |
428 | ||
429 | jzchan->desc = to_jz4780_dma_desc(vdesc); | |
430 | jzchan->curr_hwdesc = 0; | |
431 | ||
432 | if (jzchan->desc->type == DMA_CYCLIC && vdesc->tx.callback) { | |
433 | /* | |
434 | * The DMA controller doesn't support triggering an | |
435 | * interrupt after processing each descriptor, only | |
436 | * after processing an entire terminated list of | |
437 | * descriptors. For a cyclic DMA setup the list of | |
438 | * descriptors is not terminated so we can never get an | |
439 | * interrupt. | |
440 | * | |
441 | * If the user requested a callback for a cyclic DMA | |
442 | * setup then we workaround this hardware limitation | |
443 | * here by degrading to a set of unlinked descriptors | |
444 | * which we will submit in sequence in response to the | |
445 | * completion of processing the previous descriptor. | |
446 | */ | |
447 | for (i = 0; i < jzchan->desc->count; i++) | |
448 | jzchan->desc->desc[i].dcm &= ~JZ_DMA_DCM_LINK; | |
449 | } | |
450 | } else { | |
451 | /* | |
452 | * There is an existing transfer, therefore this must be one | |
453 | * for which we unlinked the descriptors above. Advance to the | |
454 | * next one in the list. | |
455 | */ | |
456 | jzchan->curr_hwdesc = | |
457 | (jzchan->curr_hwdesc + 1) % jzchan->desc->count; | |
458 | } | |
459 | ||
460 | /* Use 8-word descriptors. */ | |
461 | jz4780_dma_writel(jzdma, JZ_DMA_REG_DCS(jzchan->id), JZ_DMA_DCS_DES8); | |
462 | ||
463 | /* Write descriptor address and initiate descriptor fetch. */ | |
464 | desc_phys = jzchan->desc->desc_phys + | |
465 | (jzchan->curr_hwdesc * sizeof(*jzchan->desc->desc)); | |
466 | jz4780_dma_writel(jzdma, JZ_DMA_REG_DDA(jzchan->id), desc_phys); | |
467 | jz4780_dma_writel(jzdma, JZ_DMA_REG_DDRS, BIT(jzchan->id)); | |
468 | ||
469 | /* Enable the channel. */ | |
470 | jz4780_dma_writel(jzdma, JZ_DMA_REG_DCS(jzchan->id), | |
471 | JZ_DMA_DCS_DES8 | JZ_DMA_DCS_CTE); | |
472 | } | |
473 | ||
474 | static void jz4780_dma_issue_pending(struct dma_chan *chan) | |
475 | { | |
476 | struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); | |
477 | unsigned long flags; | |
478 | ||
479 | spin_lock_irqsave(&jzchan->vchan.lock, flags); | |
480 | ||
481 | if (vchan_issue_pending(&jzchan->vchan) && !jzchan->desc) | |
482 | jz4780_dma_begin(jzchan); | |
483 | ||
484 | spin_unlock_irqrestore(&jzchan->vchan.lock, flags); | |
485 | } | |
486 | ||
487 | static int jz4780_dma_terminate_all(struct jz4780_dma_chan *jzchan) | |
488 | { | |
489 | struct jz4780_dma_dev *jzdma = jz4780_dma_chan_parent(jzchan); | |
490 | unsigned long flags; | |
491 | LIST_HEAD(head); | |
492 | ||
493 | spin_lock_irqsave(&jzchan->vchan.lock, flags); | |
494 | ||
495 | /* Clear the DMA status and stop the transfer. */ | |
496 | jz4780_dma_writel(jzdma, JZ_DMA_REG_DCS(jzchan->id), 0); | |
497 | if (jzchan->desc) { | |
498 | jz4780_dma_desc_free(&jzchan->desc->vdesc); | |
499 | jzchan->desc = NULL; | |
500 | } | |
501 | ||
502 | vchan_get_all_descriptors(&jzchan->vchan, &head); | |
503 | ||
504 | spin_unlock_irqrestore(&jzchan->vchan.lock, flags); | |
505 | ||
506 | vchan_dma_desc_free_list(&jzchan->vchan, &head); | |
507 | return 0; | |
508 | } | |
509 | ||
510 | static int jz4780_dma_slave_config(struct jz4780_dma_chan *jzchan, | |
511 | const struct dma_slave_config *config) | |
512 | { | |
513 | if ((config->src_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES) | |
514 | || (config->dst_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES)) | |
515 | return -EINVAL; | |
516 | ||
517 | /* Copy the reset of the slave configuration, it is used later. */ | |
518 | memcpy(&jzchan->config, config, sizeof(jzchan->config)); | |
519 | ||
520 | return 0; | |
521 | } | |
522 | ||
523 | static size_t jz4780_dma_desc_residue(struct jz4780_dma_chan *jzchan, | |
524 | struct jz4780_dma_desc *desc, unsigned int next_sg) | |
525 | { | |
526 | struct jz4780_dma_dev *jzdma = jz4780_dma_chan_parent(jzchan); | |
527 | unsigned int residue, count; | |
528 | unsigned int i; | |
529 | ||
530 | residue = 0; | |
531 | ||
532 | for (i = next_sg; i < desc->count; i++) | |
533 | residue += desc->desc[i].dtc << jzchan->transfer_shift; | |
534 | ||
535 | if (next_sg != 0) { | |
536 | count = jz4780_dma_readl(jzdma, | |
537 | JZ_DMA_REG_DTC(jzchan->id)); | |
538 | residue += count << jzchan->transfer_shift; | |
539 | } | |
540 | ||
541 | return residue; | |
542 | } | |
543 | ||
544 | static enum dma_status jz4780_dma_tx_status(struct dma_chan *chan, | |
545 | dma_cookie_t cookie, struct dma_tx_state *txstate) | |
546 | { | |
547 | struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); | |
548 | struct virt_dma_desc *vdesc; | |
549 | enum dma_status status; | |
550 | unsigned long flags; | |
551 | ||
552 | status = dma_cookie_status(chan, cookie, txstate); | |
553 | if ((status == DMA_COMPLETE) || (txstate == NULL)) | |
554 | return status; | |
555 | ||
556 | spin_lock_irqsave(&jzchan->vchan.lock, flags); | |
557 | ||
558 | vdesc = vchan_find_desc(&jzchan->vchan, cookie); | |
559 | if (vdesc) { | |
560 | /* On the issued list, so hasn't been processed yet */ | |
561 | txstate->residue = jz4780_dma_desc_residue(jzchan, | |
562 | to_jz4780_dma_desc(vdesc), 0); | |
563 | } else if (cookie == jzchan->desc->vdesc.tx.cookie) { | |
564 | txstate->residue = jz4780_dma_desc_residue(jzchan, jzchan->desc, | |
565 | (jzchan->curr_hwdesc + 1) % jzchan->desc->count); | |
566 | } else | |
567 | txstate->residue = 0; | |
568 | ||
569 | if (vdesc && jzchan->desc && vdesc == &jzchan->desc->vdesc | |
570 | && jzchan->desc->status & (JZ_DMA_DCS_AR | JZ_DMA_DCS_HLT)) | |
571 | status = DMA_ERROR; | |
572 | ||
573 | spin_unlock_irqrestore(&jzchan->vchan.lock, flags); | |
574 | return status; | |
575 | } | |
576 | ||
577 | static void jz4780_dma_chan_irq(struct jz4780_dma_dev *jzdma, | |
578 | struct jz4780_dma_chan *jzchan) | |
579 | { | |
580 | uint32_t dcs; | |
581 | ||
582 | spin_lock(&jzchan->vchan.lock); | |
583 | ||
584 | dcs = jz4780_dma_readl(jzdma, JZ_DMA_REG_DCS(jzchan->id)); | |
585 | jz4780_dma_writel(jzdma, JZ_DMA_REG_DCS(jzchan->id), 0); | |
586 | ||
587 | if (dcs & JZ_DMA_DCS_AR) { | |
588 | dev_warn(&jzchan->vchan.chan.dev->device, | |
589 | "address error (DCS=0x%x)\n", dcs); | |
590 | } | |
591 | ||
592 | if (dcs & JZ_DMA_DCS_HLT) { | |
593 | dev_warn(&jzchan->vchan.chan.dev->device, | |
594 | "channel halt (DCS=0x%x)\n", dcs); | |
595 | } | |
596 | ||
597 | if (jzchan->desc) { | |
598 | jzchan->desc->status = dcs; | |
599 | ||
600 | if ((dcs & (JZ_DMA_DCS_AR | JZ_DMA_DCS_HLT)) == 0) { | |
601 | if (jzchan->desc->type == DMA_CYCLIC) { | |
602 | vchan_cyclic_callback(&jzchan->desc->vdesc); | |
603 | } else { | |
604 | vchan_cookie_complete(&jzchan->desc->vdesc); | |
605 | jzchan->desc = NULL; | |
606 | } | |
607 | ||
608 | jz4780_dma_begin(jzchan); | |
609 | } | |
610 | } else { | |
611 | dev_err(&jzchan->vchan.chan.dev->device, | |
612 | "channel IRQ with no active transfer\n"); | |
613 | } | |
614 | ||
615 | spin_unlock(&jzchan->vchan.lock); | |
616 | } | |
617 | ||
618 | static irqreturn_t jz4780_dma_irq_handler(int irq, void *data) | |
619 | { | |
620 | struct jz4780_dma_dev *jzdma = data; | |
621 | uint32_t pending, dmac; | |
622 | int i; | |
623 | ||
624 | pending = jz4780_dma_readl(jzdma, JZ_DMA_REG_DIRQP); | |
625 | ||
626 | for (i = 0; i < JZ_DMA_NR_CHANNELS; i++) { | |
627 | if (!(pending & (1<<i))) | |
628 | continue; | |
629 | ||
630 | jz4780_dma_chan_irq(jzdma, &jzdma->chan[i]); | |
631 | } | |
632 | ||
633 | /* Clear halt and address error status of all channels. */ | |
634 | dmac = jz4780_dma_readl(jzdma, JZ_DMA_REG_DMAC); | |
635 | dmac &= ~(JZ_DMA_DMAC_HLT | JZ_DMA_DMAC_AR); | |
636 | jz4780_dma_writel(jzdma, JZ_DMA_REG_DMAC, dmac); | |
637 | ||
638 | /* Clear interrupt pending status. */ | |
639 | jz4780_dma_writel(jzdma, JZ_DMA_REG_DIRQP, 0); | |
640 | ||
641 | return IRQ_HANDLED; | |
642 | } | |
643 | ||
644 | static int jz4780_dma_alloc_chan_resources(struct dma_chan *chan) | |
645 | { | |
646 | struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); | |
647 | ||
648 | jzchan->desc_pool = dma_pool_create(dev_name(&chan->dev->device), | |
649 | chan->device->dev, | |
650 | JZ_DMA_DESC_BLOCK_SIZE, | |
651 | PAGE_SIZE, 0); | |
652 | if (!jzchan->desc_pool) { | |
653 | dev_err(&chan->dev->device, | |
654 | "failed to allocate descriptor pool\n"); | |
655 | return -ENOMEM; | |
656 | } | |
657 | ||
658 | return 0; | |
659 | } | |
660 | ||
661 | static void jz4780_dma_free_chan_resources(struct dma_chan *chan) | |
662 | { | |
663 | struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); | |
664 | ||
665 | vchan_free_chan_resources(&jzchan->vchan); | |
666 | dma_pool_destroy(jzchan->desc_pool); | |
667 | jzchan->desc_pool = NULL; | |
668 | } | |
669 | ||
670 | static bool jz4780_dma_filter_fn(struct dma_chan *chan, void *param) | |
671 | { | |
672 | struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); | |
673 | struct jz4780_dma_dev *jzdma = jz4780_dma_chan_parent(jzchan); | |
674 | struct jz4780_dma_data *data = param; | |
675 | ||
676 | if (data->channel > -1) { | |
677 | if (data->channel != jzchan->id) | |
678 | return false; | |
679 | } else if (jzdma->chan_reserved & BIT(jzchan->id)) { | |
680 | return false; | |
681 | } | |
682 | ||
683 | jzchan->transfer_type = data->transfer_type; | |
684 | ||
685 | return true; | |
686 | } | |
687 | ||
688 | static struct dma_chan *jz4780_of_dma_xlate(struct of_phandle_args *dma_spec, | |
689 | struct of_dma *ofdma) | |
690 | { | |
691 | struct jz4780_dma_dev *jzdma = ofdma->of_dma_data; | |
692 | dma_cap_mask_t mask = jzdma->dma_device.cap_mask; | |
693 | struct jz4780_dma_data data; | |
694 | ||
695 | if (dma_spec->args_count != 2) | |
696 | return NULL; | |
697 | ||
698 | data.transfer_type = dma_spec->args[0]; | |
699 | data.channel = dma_spec->args[1]; | |
700 | ||
701 | if (data.channel > -1) { | |
702 | if (data.channel >= JZ_DMA_NR_CHANNELS) { | |
703 | dev_err(jzdma->dma_device.dev, | |
704 | "device requested non-existent channel %u\n", | |
705 | data.channel); | |
706 | return NULL; | |
707 | } | |
708 | ||
709 | /* Can only select a channel marked as reserved. */ | |
710 | if (!(jzdma->chan_reserved & BIT(data.channel))) { | |
711 | dev_err(jzdma->dma_device.dev, | |
712 | "device requested unreserved channel %u\n", | |
713 | data.channel); | |
714 | return NULL; | |
715 | } | |
716 | } | |
717 | ||
718 | return dma_request_channel(mask, jz4780_dma_filter_fn, &data); | |
719 | } | |
720 | ||
721 | static int jz4780_dma_probe(struct platform_device *pdev) | |
722 | { | |
723 | struct device *dev = &pdev->dev; | |
724 | struct jz4780_dma_dev *jzdma; | |
725 | struct jz4780_dma_chan *jzchan; | |
726 | struct dma_device *dd; | |
727 | struct resource *res; | |
728 | int i, ret; | |
729 | ||
730 | jzdma = devm_kzalloc(dev, sizeof(*jzdma), GFP_KERNEL); | |
731 | if (!jzdma) | |
732 | return -ENOMEM; | |
733 | ||
734 | platform_set_drvdata(pdev, jzdma); | |
735 | ||
736 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
737 | if (!res) { | |
738 | dev_err(dev, "failed to get I/O memory\n"); | |
739 | return -EINVAL; | |
740 | } | |
741 | ||
742 | jzdma->base = devm_ioremap_resource(dev, res); | |
743 | if (IS_ERR(jzdma->base)) | |
744 | return PTR_ERR(jzdma->base); | |
745 | ||
746 | jzdma->irq = platform_get_irq(pdev, 0); | |
747 | if (jzdma->irq < 0) { | |
748 | dev_err(dev, "failed to get IRQ: %d\n", ret); | |
749 | return jzdma->irq; | |
750 | } | |
751 | ||
752 | ret = devm_request_irq(dev, jzdma->irq, jz4780_dma_irq_handler, 0, | |
753 | dev_name(dev), jzdma); | |
754 | if (ret) { | |
755 | dev_err(dev, "failed to request IRQ %u!\n", jzdma->irq); | |
756 | return -EINVAL; | |
757 | } | |
758 | ||
759 | jzdma->clk = devm_clk_get(dev, NULL); | |
760 | if (IS_ERR(jzdma->clk)) { | |
761 | dev_err(dev, "failed to get clock\n"); | |
762 | return PTR_ERR(jzdma->clk); | |
763 | } | |
764 | ||
765 | clk_prepare_enable(jzdma->clk); | |
766 | ||
767 | /* Property is optional, if it doesn't exist the value will remain 0. */ | |
768 | of_property_read_u32_index(dev->of_node, "ingenic,reserved-channels", | |
769 | 0, &jzdma->chan_reserved); | |
770 | ||
771 | dd = &jzdma->dma_device; | |
772 | ||
773 | dma_cap_set(DMA_MEMCPY, dd->cap_mask); | |
774 | dma_cap_set(DMA_SLAVE, dd->cap_mask); | |
775 | dma_cap_set(DMA_CYCLIC, dd->cap_mask); | |
776 | ||
777 | dd->dev = dev; | |
778 | dd->copy_align = 2; /* 2^2 = 4 byte alignment */ | |
779 | dd->device_alloc_chan_resources = jz4780_dma_alloc_chan_resources; | |
780 | dd->device_free_chan_resources = jz4780_dma_free_chan_resources; | |
781 | dd->device_prep_slave_sg = jz4780_dma_prep_slave_sg; | |
782 | dd->device_prep_dma_cyclic = jz4780_dma_prep_dma_cyclic; | |
783 | dd->device_prep_dma_memcpy = jz4780_dma_prep_dma_memcpy; | |
784 | dd->device_config = jz4780_dma_slave_config; | |
785 | dd->device_terminate_all = jz4780_dma_terminate_all; | |
786 | dd->device_tx_status = jz4780_dma_tx_status; | |
787 | dd->device_issue_pending = jz4780_dma_issue_pending; | |
788 | dd->src_addr_widths = JZ_DMA_BUSWIDTHS; | |
789 | dd->dst_addr_widths = JZ_DMA_BUSWIDTHS; | |
790 | dd->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV); | |
791 | dd->residue_granularity = DMA_RESIDUE_GRANULARITY_BURST; | |
792 | ||
793 | ||
794 | /* | |
795 | * Enable DMA controller, mark all channels as not programmable. | |
796 | * Also set the FMSC bit - it increases MSC performance, so it makes | |
797 | * little sense not to enable it. | |
798 | */ | |
799 | jz4780_dma_writel(jzdma, JZ_DMA_REG_DMAC, | |
800 | JZ_DMA_DMAC_DMAE | JZ_DMA_DMAC_FMSC); | |
801 | jz4780_dma_writel(jzdma, JZ_DMA_REG_DMACP, 0); | |
802 | ||
803 | INIT_LIST_HEAD(&dd->channels); | |
804 | ||
805 | for (i = 0; i < JZ_DMA_NR_CHANNELS; i++) { | |
806 | jzchan = &jzdma->chan[i]; | |
807 | jzchan->id = i; | |
808 | ||
809 | vchan_init(&jzchan->vchan, dd); | |
810 | jzchan->vchan.desc_free = jz4780_dma_desc_free; | |
811 | } | |
812 | ||
813 | ret = dma_async_device_register(dd); | |
814 | if (ret) { | |
815 | dev_err(dev, "failed to register device\n"); | |
816 | goto err_disable_clk; | |
817 | } | |
818 | ||
819 | /* Register with OF DMA helpers. */ | |
820 | ret = of_dma_controller_register(dev->of_node, jz4780_of_dma_xlate, | |
821 | jzdma); | |
822 | if (ret) { | |
823 | dev_err(dev, "failed to register OF DMA controller\n"); | |
824 | goto err_unregister_dev; | |
825 | } | |
826 | ||
827 | dev_info(dev, "JZ4780 DMA controller initialised\n"); | |
828 | return 0; | |
829 | ||
830 | err_unregister_dev: | |
831 | dma_async_device_unregister(dd); | |
832 | ||
833 | err_disable_clk: | |
834 | clk_disable_unprepare(jzdma->clk); | |
835 | return ret; | |
836 | } | |
837 | ||
838 | static int jz4780_dma_remove(struct platform_device *pdev) | |
839 | { | |
840 | struct jz4780_dma_dev *jzdma = platform_get_drvdata(pdev); | |
841 | ||
842 | of_dma_controller_free(pdev->dev.of_node); | |
843 | devm_free_irq(&pdev->dev, jzdma->irq, jzdma); | |
844 | dma_async_device_unregister(&jzdma->dma_device); | |
845 | return 0; | |
846 | } | |
847 | ||
848 | static const struct of_device_id jz4780_dma_dt_match[] = { | |
849 | { .compatible = "ingenic,jz4780-dma", .data = NULL }, | |
850 | {}, | |
851 | }; | |
852 | MODULE_DEVICE_TABLE(of, jz4780_dma_dt_match); | |
853 | ||
854 | static struct platform_driver jz4780_dma_driver = { | |
855 | .probe = jz4780_dma_probe, | |
856 | .remove = jz4780_dma_remove, | |
857 | .driver = { | |
858 | .name = "jz4780-dma", | |
859 | .of_match_table = of_match_ptr(jz4780_dma_dt_match), | |
860 | }, | |
861 | }; | |
862 | ||
863 | static int __init jz4780_dma_init(void) | |
864 | { | |
865 | return platform_driver_register(&jz4780_dma_driver); | |
866 | } | |
867 | subsys_initcall(jz4780_dma_init); | |
868 | ||
869 | static void __exit jz4780_dma_exit(void) | |
870 | { | |
871 | platform_driver_unregister(&jz4780_dma_driver); | |
872 | } | |
873 | module_exit(jz4780_dma_exit); | |
874 | ||
875 | MODULE_AUTHOR("Alex Smith <alex@alex-smith.me.uk>"); | |
876 | MODULE_DESCRIPTION("Ingenic JZ4780 DMA controller driver"); | |
877 | MODULE_LICENSE("GPL"); |