diff options
Diffstat (limited to 'drivers/dma')
-rw-r--r-- | drivers/dma/Kconfig | 7 | ||||
-rw-r--r-- | drivers/dma/Makefile | 1 | ||||
-rw-r--r-- | drivers/dma/ep93xx_dma.c | 1355 |
3 files changed, 1363 insertions, 0 deletions
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig index 25cf327cd1cb..2e3b3d38c465 100644 --- a/drivers/dma/Kconfig +++ b/drivers/dma/Kconfig | |||
@@ -237,6 +237,13 @@ config MXS_DMA | |||
237 | Support the MXS DMA engine. This engine including APBH-DMA | 237 | Support the MXS DMA engine. This engine including APBH-DMA |
238 | and APBX-DMA is integrated into Freescale i.MX23/28 chips. | 238 | and APBX-DMA is integrated into Freescale i.MX23/28 chips. |
239 | 239 | ||
240 | config EP93XX_DMA | ||
241 | bool "Cirrus Logic EP93xx DMA support" | ||
242 | depends on ARCH_EP93XX | ||
243 | select DMA_ENGINE | ||
244 | help | ||
245 | Enable support for the Cirrus Logic EP93xx M2P/M2M DMA controller. | ||
246 | |||
240 | config DMA_ENGINE | 247 | config DMA_ENGINE |
241 | bool | 248 | bool |
242 | 249 | ||
diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile index 836095ab3c5c..30cf3b1f0c5c 100644 --- a/drivers/dma/Makefile +++ b/drivers/dma/Makefile | |||
@@ -25,3 +25,4 @@ obj-$(CONFIG_STE_DMA40) += ste_dma40.o ste_dma40_ll.o | |||
25 | obj-$(CONFIG_PL330_DMA) += pl330.o | 25 | obj-$(CONFIG_PL330_DMA) += pl330.o |
26 | obj-$(CONFIG_PCH_DMA) += pch_dma.o | 26 | obj-$(CONFIG_PCH_DMA) += pch_dma.o |
27 | obj-$(CONFIG_AMBA_PL08X) += amba-pl08x.o | 27 | obj-$(CONFIG_AMBA_PL08X) += amba-pl08x.o |
28 | obj-$(CONFIG_EP93XX_DMA) += ep93xx_dma.o | ||
diff --git a/drivers/dma/ep93xx_dma.c b/drivers/dma/ep93xx_dma.c new file mode 100644 index 000000000000..0766c1e53b1d --- /dev/null +++ b/drivers/dma/ep93xx_dma.c | |||
@@ -0,0 +1,1355 @@ | |||
1 | /* | ||
2 | * Driver for the Cirrus Logic EP93xx DMA Controller | ||
3 | * | ||
4 | * Copyright (C) 2011 Mika Westerberg | ||
5 | * | ||
6 | * DMA M2P implementation is based on the original | ||
7 | * arch/arm/mach-ep93xx/dma-m2p.c which has following copyrights: | ||
8 | * | ||
9 | * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org> | ||
10 | * Copyright (C) 2006 Applied Data Systems | ||
11 | * Copyright (C) 2009 Ryan Mallon <rmallon@gmail.com> | ||
12 | * | ||
13 | * This driver is based on dw_dmac and amba-pl08x drivers. | ||
14 | * | ||
15 | * This program is free software; you can redistribute it and/or modify | ||
16 | * it under the terms of the GNU General Public License as published by | ||
17 | * the Free Software Foundation; either version 2 of the License, or | ||
18 | * (at your option) any later version. | ||
19 | */ | ||
20 | |||
21 | #include <linux/clk.h> | ||
22 | #include <linux/init.h> | ||
23 | #include <linux/interrupt.h> | ||
24 | #include <linux/dmaengine.h> | ||
25 | #include <linux/platform_device.h> | ||
26 | #include <linux/slab.h> | ||
27 | |||
28 | #include <mach/dma.h> | ||
29 | |||
30 | /* M2P registers */ | ||
31 | #define M2P_CONTROL 0x0000 | ||
32 | #define M2P_CONTROL_STALLINT BIT(0) | ||
33 | #define M2P_CONTROL_NFBINT BIT(1) | ||
34 | #define M2P_CONTROL_CH_ERROR_INT BIT(3) | ||
35 | #define M2P_CONTROL_ENABLE BIT(4) | ||
36 | #define M2P_CONTROL_ICE BIT(6) | ||
37 | |||
38 | #define M2P_INTERRUPT 0x0004 | ||
39 | #define M2P_INTERRUPT_STALL BIT(0) | ||
40 | #define M2P_INTERRUPT_NFB BIT(1) | ||
41 | #define M2P_INTERRUPT_ERROR BIT(3) | ||
42 | |||
43 | #define M2P_PPALLOC 0x0008 | ||
44 | #define M2P_STATUS 0x000c | ||
45 | |||
46 | #define M2P_MAXCNT0 0x0020 | ||
47 | #define M2P_BASE0 0x0024 | ||
48 | #define M2P_MAXCNT1 0x0030 | ||
49 | #define M2P_BASE1 0x0034 | ||
50 | |||
51 | #define M2P_STATE_IDLE 0 | ||
52 | #define M2P_STATE_STALL 1 | ||
53 | #define M2P_STATE_ON 2 | ||
54 | #define M2P_STATE_NEXT 3 | ||
55 | |||
56 | /* M2M registers */ | ||
57 | #define M2M_CONTROL 0x0000 | ||
58 | #define M2M_CONTROL_DONEINT BIT(2) | ||
59 | #define M2M_CONTROL_ENABLE BIT(3) | ||
60 | #define M2M_CONTROL_START BIT(4) | ||
61 | #define M2M_CONTROL_DAH BIT(11) | ||
62 | #define M2M_CONTROL_SAH BIT(12) | ||
63 | #define M2M_CONTROL_PW_SHIFT 9 | ||
64 | #define M2M_CONTROL_PW_8 (0 << M2M_CONTROL_PW_SHIFT) | ||
65 | #define M2M_CONTROL_PW_16 (1 << M2M_CONTROL_PW_SHIFT) | ||
66 | #define M2M_CONTROL_PW_32 (2 << M2M_CONTROL_PW_SHIFT) | ||
67 | #define M2M_CONTROL_PW_MASK (3 << M2M_CONTROL_PW_SHIFT) | ||
68 | #define M2M_CONTROL_TM_SHIFT 13 | ||
69 | #define M2M_CONTROL_TM_TX (1 << M2M_CONTROL_TM_SHIFT) | ||
70 | #define M2M_CONTROL_TM_RX (2 << M2M_CONTROL_TM_SHIFT) | ||
71 | #define M2M_CONTROL_RSS_SHIFT 22 | ||
72 | #define M2M_CONTROL_RSS_SSPRX (1 << M2M_CONTROL_RSS_SHIFT) | ||
73 | #define M2M_CONTROL_RSS_SSPTX (2 << M2M_CONTROL_RSS_SHIFT) | ||
74 | #define M2M_CONTROL_RSS_IDE (3 << M2M_CONTROL_RSS_SHIFT) | ||
75 | #define M2M_CONTROL_NO_HDSK BIT(24) | ||
76 | #define M2M_CONTROL_PWSC_SHIFT 25 | ||
77 | |||
78 | #define M2M_INTERRUPT 0x0004 | ||
79 | #define M2M_INTERRUPT_DONEINT BIT(1) | ||
80 | |||
81 | #define M2M_BCR0 0x0010 | ||
82 | #define M2M_BCR1 0x0014 | ||
83 | #define M2M_SAR_BASE0 0x0018 | ||
84 | #define M2M_SAR_BASE1 0x001c | ||
85 | #define M2M_DAR_BASE0 0x002c | ||
86 | #define M2M_DAR_BASE1 0x0030 | ||
87 | |||
88 | #define DMA_MAX_CHAN_BYTES 0xffff | ||
89 | #define DMA_MAX_CHAN_DESCRIPTORS 32 | ||
90 | |||
91 | struct ep93xx_dma_engine; | ||
92 | |||
93 | /** | ||
94 | * struct ep93xx_dma_desc - EP93xx specific transaction descriptor | ||
95 | * @src_addr: source address of the transaction | ||
96 | * @dst_addr: destination address of the transaction | ||
97 | * @size: size of the transaction (in bytes) | ||
98 | * @complete: this descriptor is completed | ||
99 | * @txd: dmaengine API descriptor | ||
100 | * @tx_list: list of linked descriptors | ||
101 | * @node: link used for putting this into a channel queue | ||
102 | */ | ||
103 | struct ep93xx_dma_desc { | ||
104 | u32 src_addr; | ||
105 | u32 dst_addr; | ||
106 | size_t size; | ||
107 | bool complete; | ||
108 | struct dma_async_tx_descriptor txd; | ||
109 | struct list_head tx_list; | ||
110 | struct list_head node; | ||
111 | }; | ||
112 | |||
113 | /** | ||
114 | * struct ep93xx_dma_chan - an EP93xx DMA M2P/M2M channel | ||
115 | * @chan: dmaengine API channel | ||
116 | * @edma: pointer to to the engine device | ||
117 | * @regs: memory mapped registers | ||
118 | * @irq: interrupt number of the channel | ||
119 | * @clk: clock used by this channel | ||
120 | * @tasklet: channel specific tasklet used for callbacks | ||
121 | * @lock: lock protecting the fields following | ||
122 | * @flags: flags for the channel | ||
123 | * @buffer: which buffer to use next (0/1) | ||
124 | * @last_completed: last completed cookie value | ||
125 | * @active: flattened chain of descriptors currently being processed | ||
126 | * @queue: pending descriptors which are handled next | ||
127 | * @free_list: list of free descriptors which can be used | ||
128 | * @runtime_addr: physical address currently used as dest/src (M2M only). This | ||
129 | * is set via %DMA_SLAVE_CONFIG before slave operation is | ||
130 | * prepared | ||
131 | * @runtime_ctrl: M2M runtime values for the control register. | ||
132 | * | ||
133 | * As EP93xx DMA controller doesn't support real chained DMA descriptors we | ||
134 | * will have slightly different scheme here: @active points to a head of | ||
135 | * flattened DMA descriptor chain. | ||
136 | * | ||
137 | * @queue holds pending transactions. These are linked through the first | ||
138 | * descriptor in the chain. When a descriptor is moved to the @active queue, | ||
139 | * the first and chained descriptors are flattened into a single list. | ||
140 | * | ||
141 | * @chan.private holds pointer to &struct ep93xx_dma_data which contains | ||
142 | * necessary channel configuration information. For memcpy channels this must | ||
143 | * be %NULL. | ||
144 | */ | ||
145 | struct ep93xx_dma_chan { | ||
146 | struct dma_chan chan; | ||
147 | const struct ep93xx_dma_engine *edma; | ||
148 | void __iomem *regs; | ||
149 | int irq; | ||
150 | struct clk *clk; | ||
151 | struct tasklet_struct tasklet; | ||
152 | /* protects the fields following */ | ||
153 | spinlock_t lock; | ||
154 | unsigned long flags; | ||
155 | /* Channel is configured for cyclic transfers */ | ||
156 | #define EP93XX_DMA_IS_CYCLIC 0 | ||
157 | |||
158 | int buffer; | ||
159 | dma_cookie_t last_completed; | ||
160 | struct list_head active; | ||
161 | struct list_head queue; | ||
162 | struct list_head free_list; | ||
163 | u32 runtime_addr; | ||
164 | u32 runtime_ctrl; | ||
165 | }; | ||
166 | |||
167 | /** | ||
168 | * struct ep93xx_dma_engine - the EP93xx DMA engine instance | ||
169 | * @dma_dev: holds the dmaengine device | ||
170 | * @m2m: is this an M2M or M2P device | ||
171 | * @hw_setup: method which sets the channel up for operation | ||
172 | * @hw_shutdown: shuts the channel down and flushes whatever is left | ||
173 | * @hw_submit: pushes active descriptor(s) to the hardware | ||
174 | * @hw_interrupt: handle the interrupt | ||
175 | * @num_channels: number of channels for this instance | ||
176 | * @channels: array of channels | ||
177 | * | ||
178 | * There is one instance of this struct for the M2P channels and one for the | ||
179 | * M2M channels. hw_xxx() methods are used to perform operations which are | ||
180 | * different on M2M and M2P channels. These methods are called with channel | ||
181 | * lock held and interrupts disabled so they cannot sleep. | ||
182 | */ | ||
183 | struct ep93xx_dma_engine { | ||
184 | struct dma_device dma_dev; | ||
185 | bool m2m; | ||
186 | int (*hw_setup)(struct ep93xx_dma_chan *); | ||
187 | void (*hw_shutdown)(struct ep93xx_dma_chan *); | ||
188 | void (*hw_submit)(struct ep93xx_dma_chan *); | ||
189 | int (*hw_interrupt)(struct ep93xx_dma_chan *); | ||
190 | #define INTERRUPT_UNKNOWN 0 | ||
191 | #define INTERRUPT_DONE 1 | ||
192 | #define INTERRUPT_NEXT_BUFFER 2 | ||
193 | |||
194 | size_t num_channels; | ||
195 | struct ep93xx_dma_chan channels[]; | ||
196 | }; | ||
197 | |||
198 | static inline struct device *chan2dev(struct ep93xx_dma_chan *edmac) | ||
199 | { | ||
200 | return &edmac->chan.dev->device; | ||
201 | } | ||
202 | |||
203 | static struct ep93xx_dma_chan *to_ep93xx_dma_chan(struct dma_chan *chan) | ||
204 | { | ||
205 | return container_of(chan, struct ep93xx_dma_chan, chan); | ||
206 | } | ||
207 | |||
208 | /** | ||
209 | * ep93xx_dma_set_active - set new active descriptor chain | ||
210 | * @edmac: channel | ||
211 | * @desc: head of the new active descriptor chain | ||
212 | * | ||
213 | * Sets @desc to be the head of the new active descriptor chain. This is the | ||
214 | * chain which is processed next. The active list must be empty before calling | ||
215 | * this function. | ||
216 | * | ||
217 | * Called with @edmac->lock held and interrupts disabled. | ||
218 | */ | ||
219 | static void ep93xx_dma_set_active(struct ep93xx_dma_chan *edmac, | ||
220 | struct ep93xx_dma_desc *desc) | ||
221 | { | ||
222 | BUG_ON(!list_empty(&edmac->active)); | ||
223 | |||
224 | list_add_tail(&desc->node, &edmac->active); | ||
225 | |||
226 | /* Flatten the @desc->tx_list chain into @edmac->active list */ | ||
227 | while (!list_empty(&desc->tx_list)) { | ||
228 | struct ep93xx_dma_desc *d = list_first_entry(&desc->tx_list, | ||
229 | struct ep93xx_dma_desc, node); | ||
230 | |||
231 | /* | ||
232 | * We copy the callback parameters from the first descriptor | ||
233 | * to all the chained descriptors. This way we can call the | ||
234 | * callback without having to find out the first descriptor in | ||
235 | * the chain. Useful for cyclic transfers. | ||
236 | */ | ||
237 | d->txd.callback = desc->txd.callback; | ||
238 | d->txd.callback_param = desc->txd.callback_param; | ||
239 | |||
240 | list_move_tail(&d->node, &edmac->active); | ||
241 | } | ||
242 | } | ||
243 | |||
244 | /* Called with @edmac->lock held and interrupts disabled */ | ||
245 | static struct ep93xx_dma_desc * | ||
246 | ep93xx_dma_get_active(struct ep93xx_dma_chan *edmac) | ||
247 | { | ||
248 | return list_first_entry(&edmac->active, struct ep93xx_dma_desc, node); | ||
249 | } | ||
250 | |||
251 | /** | ||
252 | * ep93xx_dma_advance_active - advances to the next active descriptor | ||
253 | * @edmac: channel | ||
254 | * | ||
255 | * Function advances active descriptor to the next in the @edmac->active and | ||
256 | * returns %true if we still have descriptors in the chain to process. | ||
257 | * Otherwise returns %false. | ||
258 | * | ||
259 | * When the channel is in cyclic mode always returns %true. | ||
260 | * | ||
261 | * Called with @edmac->lock held and interrupts disabled. | ||
262 | */ | ||
263 | static bool ep93xx_dma_advance_active(struct ep93xx_dma_chan *edmac) | ||
264 | { | ||
265 | list_rotate_left(&edmac->active); | ||
266 | |||
267 | if (test_bit(EP93XX_DMA_IS_CYCLIC, &edmac->flags)) | ||
268 | return true; | ||
269 | |||
270 | /* | ||
271 | * If txd.cookie is set it means that we are back in the first | ||
272 | * descriptor in the chain and hence done with it. | ||
273 | */ | ||
274 | return !ep93xx_dma_get_active(edmac)->txd.cookie; | ||
275 | } | ||
276 | |||
277 | /* | ||
278 | * M2P DMA implementation | ||
279 | */ | ||
280 | |||
281 | static void m2p_set_control(struct ep93xx_dma_chan *edmac, u32 control) | ||
282 | { | ||
283 | writel(control, edmac->regs + M2P_CONTROL); | ||
284 | /* | ||
285 | * EP93xx User's Guide states that we must perform a dummy read after | ||
286 | * write to the control register. | ||
287 | */ | ||
288 | readl(edmac->regs + M2P_CONTROL); | ||
289 | } | ||
290 | |||
291 | static int m2p_hw_setup(struct ep93xx_dma_chan *edmac) | ||
292 | { | ||
293 | struct ep93xx_dma_data *data = edmac->chan.private; | ||
294 | u32 control; | ||
295 | |||
296 | writel(data->port & 0xf, edmac->regs + M2P_PPALLOC); | ||
297 | |||
298 | control = M2P_CONTROL_CH_ERROR_INT | M2P_CONTROL_ICE | ||
299 | | M2P_CONTROL_ENABLE; | ||
300 | m2p_set_control(edmac, control); | ||
301 | |||
302 | return 0; | ||
303 | } | ||
304 | |||
305 | static inline u32 m2p_channel_state(struct ep93xx_dma_chan *edmac) | ||
306 | { | ||
307 | return (readl(edmac->regs + M2P_STATUS) >> 4) & 0x3; | ||
308 | } | ||
309 | |||
310 | static void m2p_hw_shutdown(struct ep93xx_dma_chan *edmac) | ||
311 | { | ||
312 | u32 control; | ||
313 | |||
314 | control = readl(edmac->regs + M2P_CONTROL); | ||
315 | control &= ~(M2P_CONTROL_STALLINT | M2P_CONTROL_NFBINT); | ||
316 | m2p_set_control(edmac, control); | ||
317 | |||
318 | while (m2p_channel_state(edmac) >= M2P_STATE_ON) | ||
319 | cpu_relax(); | ||
320 | |||
321 | m2p_set_control(edmac, 0); | ||
322 | |||
323 | while (m2p_channel_state(edmac) == M2P_STATE_STALL) | ||
324 | cpu_relax(); | ||
325 | } | ||
326 | |||
327 | static void m2p_fill_desc(struct ep93xx_dma_chan *edmac) | ||
328 | { | ||
329 | struct ep93xx_dma_desc *desc = ep93xx_dma_get_active(edmac); | ||
330 | u32 bus_addr; | ||
331 | |||
332 | if (ep93xx_dma_chan_direction(&edmac->chan) == DMA_TO_DEVICE) | ||
333 | bus_addr = desc->src_addr; | ||
334 | else | ||
335 | bus_addr = desc->dst_addr; | ||
336 | |||
337 | if (edmac->buffer == 0) { | ||
338 | writel(desc->size, edmac->regs + M2P_MAXCNT0); | ||
339 | writel(bus_addr, edmac->regs + M2P_BASE0); | ||
340 | } else { | ||
341 | writel(desc->size, edmac->regs + M2P_MAXCNT1); | ||
342 | writel(bus_addr, edmac->regs + M2P_BASE1); | ||
343 | } | ||
344 | |||
345 | edmac->buffer ^= 1; | ||
346 | } | ||
347 | |||
348 | static void m2p_hw_submit(struct ep93xx_dma_chan *edmac) | ||
349 | { | ||
350 | u32 control = readl(edmac->regs + M2P_CONTROL); | ||
351 | |||
352 | m2p_fill_desc(edmac); | ||
353 | control |= M2P_CONTROL_STALLINT; | ||
354 | |||
355 | if (ep93xx_dma_advance_active(edmac)) { | ||
356 | m2p_fill_desc(edmac); | ||
357 | control |= M2P_CONTROL_NFBINT; | ||
358 | } | ||
359 | |||
360 | m2p_set_control(edmac, control); | ||
361 | } | ||
362 | |||
363 | static int m2p_hw_interrupt(struct ep93xx_dma_chan *edmac) | ||
364 | { | ||
365 | u32 irq_status = readl(edmac->regs + M2P_INTERRUPT); | ||
366 | u32 control; | ||
367 | |||
368 | if (irq_status & M2P_INTERRUPT_ERROR) { | ||
369 | struct ep93xx_dma_desc *desc = ep93xx_dma_get_active(edmac); | ||
370 | |||
371 | /* Clear the error interrupt */ | ||
372 | writel(1, edmac->regs + M2P_INTERRUPT); | ||
373 | |||
374 | /* | ||
375 | * It seems that there is no easy way of reporting errors back | ||
376 | * to client so we just report the error here and continue as | ||
377 | * usual. | ||
378 | * | ||
379 | * Revisit this when there is a mechanism to report back the | ||
380 | * errors. | ||
381 | */ | ||
382 | dev_err(chan2dev(edmac), | ||
383 | "DMA transfer failed! Details:\n" | ||
384 | "\tcookie : %d\n" | ||
385 | "\tsrc_addr : 0x%08x\n" | ||
386 | "\tdst_addr : 0x%08x\n" | ||
387 | "\tsize : %zu\n", | ||
388 | desc->txd.cookie, desc->src_addr, desc->dst_addr, | ||
389 | desc->size); | ||
390 | } | ||
391 | |||
392 | switch (irq_status & (M2P_INTERRUPT_STALL | M2P_INTERRUPT_NFB)) { | ||
393 | case M2P_INTERRUPT_STALL: | ||
394 | /* Disable interrupts */ | ||
395 | control = readl(edmac->regs + M2P_CONTROL); | ||
396 | control &= ~(M2P_CONTROL_STALLINT | M2P_CONTROL_NFBINT); | ||
397 | m2p_set_control(edmac, control); | ||
398 | |||
399 | return INTERRUPT_DONE; | ||
400 | |||
401 | case M2P_INTERRUPT_NFB: | ||
402 | if (ep93xx_dma_advance_active(edmac)) | ||
403 | m2p_fill_desc(edmac); | ||
404 | |||
405 | return INTERRUPT_NEXT_BUFFER; | ||
406 | } | ||
407 | |||
408 | return INTERRUPT_UNKNOWN; | ||
409 | } | ||
410 | |||
411 | /* | ||
412 | * M2M DMA implementation | ||
413 | * | ||
414 | * For the M2M transfers we don't use NFB at all. This is because it simply | ||
415 | * doesn't work well with memcpy transfers. When you submit both buffers it is | ||
416 | * extremely unlikely that you get an NFB interrupt, but it instead reports | ||
417 | * DONE interrupt and both buffers are already transferred which means that we | ||
418 | * weren't able to update the next buffer. | ||
419 | * | ||
420 | * So for now we "simulate" NFB by just submitting buffer after buffer | ||
421 | * without double buffering. | ||
422 | */ | ||
423 | |||
424 | static int m2m_hw_setup(struct ep93xx_dma_chan *edmac) | ||
425 | { | ||
426 | const struct ep93xx_dma_data *data = edmac->chan.private; | ||
427 | u32 control = 0; | ||
428 | |||
429 | if (!data) { | ||
430 | /* This is memcpy channel, nothing to configure */ | ||
431 | writel(control, edmac->regs + M2M_CONTROL); | ||
432 | return 0; | ||
433 | } | ||
434 | |||
435 | switch (data->port) { | ||
436 | case EP93XX_DMA_SSP: | ||
437 | /* | ||
438 | * This was found via experimenting - anything less than 5 | ||
439 | * causes the channel to perform only a partial transfer which | ||
440 | * leads to problems since we don't get DONE interrupt then. | ||
441 | */ | ||
442 | control = (5 << M2M_CONTROL_PWSC_SHIFT); | ||
443 | control |= M2M_CONTROL_NO_HDSK; | ||
444 | |||
445 | if (data->direction == DMA_TO_DEVICE) { | ||
446 | control |= M2M_CONTROL_DAH; | ||
447 | control |= M2M_CONTROL_TM_TX; | ||
448 | control |= M2M_CONTROL_RSS_SSPTX; | ||
449 | } else { | ||
450 | control |= M2M_CONTROL_SAH; | ||
451 | control |= M2M_CONTROL_TM_RX; | ||
452 | control |= M2M_CONTROL_RSS_SSPRX; | ||
453 | } | ||
454 | break; | ||
455 | |||
456 | case EP93XX_DMA_IDE: | ||
457 | /* | ||
458 | * This IDE part is totally untested. Values below are taken | ||
459 | * from the EP93xx Users's Guide and might not be correct. | ||
460 | */ | ||
461 | control |= M2M_CONTROL_NO_HDSK; | ||
462 | control |= M2M_CONTROL_RSS_IDE; | ||
463 | control |= M2M_CONTROL_PW_16; | ||
464 | |||
465 | if (data->direction == DMA_TO_DEVICE) { | ||
466 | /* Worst case from the UG */ | ||
467 | control = (3 << M2M_CONTROL_PWSC_SHIFT); | ||
468 | control |= M2M_CONTROL_DAH; | ||
469 | control |= M2M_CONTROL_TM_TX; | ||
470 | } else { | ||
471 | control = (2 << M2M_CONTROL_PWSC_SHIFT); | ||
472 | control |= M2M_CONTROL_SAH; | ||
473 | control |= M2M_CONTROL_TM_RX; | ||
474 | } | ||
475 | break; | ||
476 | |||
477 | default: | ||
478 | return -EINVAL; | ||
479 | } | ||
480 | |||
481 | writel(control, edmac->regs + M2M_CONTROL); | ||
482 | return 0; | ||
483 | } | ||
484 | |||
485 | static void m2m_hw_shutdown(struct ep93xx_dma_chan *edmac) | ||
486 | { | ||
487 | /* Just disable the channel */ | ||
488 | writel(0, edmac->regs + M2M_CONTROL); | ||
489 | } | ||
490 | |||
491 | static void m2m_fill_desc(struct ep93xx_dma_chan *edmac) | ||
492 | { | ||
493 | struct ep93xx_dma_desc *desc = ep93xx_dma_get_active(edmac); | ||
494 | |||
495 | if (edmac->buffer == 0) { | ||
496 | writel(desc->src_addr, edmac->regs + M2M_SAR_BASE0); | ||
497 | writel(desc->dst_addr, edmac->regs + M2M_DAR_BASE0); | ||
498 | writel(desc->size, edmac->regs + M2M_BCR0); | ||
499 | } else { | ||
500 | writel(desc->src_addr, edmac->regs + M2M_SAR_BASE1); | ||
501 | writel(desc->dst_addr, edmac->regs + M2M_DAR_BASE1); | ||
502 | writel(desc->size, edmac->regs + M2M_BCR1); | ||
503 | } | ||
504 | |||
505 | edmac->buffer ^= 1; | ||
506 | } | ||
507 | |||
508 | static void m2m_hw_submit(struct ep93xx_dma_chan *edmac) | ||
509 | { | ||
510 | struct ep93xx_dma_data *data = edmac->chan.private; | ||
511 | u32 control = readl(edmac->regs + M2M_CONTROL); | ||
512 | |||
513 | /* | ||
514 | * Since we allow clients to configure PW (peripheral width) we always | ||
515 | * clear PW bits here and then set them according what is given in | ||
516 | * the runtime configuration. | ||
517 | */ | ||
518 | control &= ~M2M_CONTROL_PW_MASK; | ||
519 | control |= edmac->runtime_ctrl; | ||
520 | |||
521 | m2m_fill_desc(edmac); | ||
522 | control |= M2M_CONTROL_DONEINT; | ||
523 | |||
524 | /* | ||
525 | * Now we can finally enable the channel. For M2M channel this must be | ||
526 | * done _after_ the BCRx registers are programmed. | ||
527 | */ | ||
528 | control |= M2M_CONTROL_ENABLE; | ||
529 | writel(control, edmac->regs + M2M_CONTROL); | ||
530 | |||
531 | if (!data) { | ||
532 | /* | ||
533 | * For memcpy channels the software trigger must be asserted | ||
534 | * in order to start the memcpy operation. | ||
535 | */ | ||
536 | control |= M2M_CONTROL_START; | ||
537 | writel(control, edmac->regs + M2M_CONTROL); | ||
538 | } | ||
539 | } | ||
540 | |||
541 | static int m2m_hw_interrupt(struct ep93xx_dma_chan *edmac) | ||
542 | { | ||
543 | u32 control; | ||
544 | |||
545 | if (!(readl(edmac->regs + M2M_INTERRUPT) & M2M_INTERRUPT_DONEINT)) | ||
546 | return INTERRUPT_UNKNOWN; | ||
547 | |||
548 | /* Clear the DONE bit */ | ||
549 | writel(0, edmac->regs + M2M_INTERRUPT); | ||
550 | |||
551 | /* Disable interrupts and the channel */ | ||
552 | control = readl(edmac->regs + M2M_CONTROL); | ||
553 | control &= ~(M2M_CONTROL_DONEINT | M2M_CONTROL_ENABLE); | ||
554 | writel(control, edmac->regs + M2M_CONTROL); | ||
555 | |||
556 | /* | ||
557 | * Since we only get DONE interrupt we have to find out ourselves | ||
558 | * whether there still is something to process. So we try to advance | ||
559 | * the chain an see whether it succeeds. | ||
560 | */ | ||
561 | if (ep93xx_dma_advance_active(edmac)) { | ||
562 | edmac->edma->hw_submit(edmac); | ||
563 | return INTERRUPT_NEXT_BUFFER; | ||
564 | } | ||
565 | |||
566 | return INTERRUPT_DONE; | ||
567 | } | ||
568 | |||
569 | /* | ||
570 | * DMA engine API implementation | ||
571 | */ | ||
572 | |||
573 | static struct ep93xx_dma_desc * | ||
574 | ep93xx_dma_desc_get(struct ep93xx_dma_chan *edmac) | ||
575 | { | ||
576 | struct ep93xx_dma_desc *desc, *_desc; | ||
577 | struct ep93xx_dma_desc *ret = NULL; | ||
578 | unsigned long flags; | ||
579 | |||
580 | spin_lock_irqsave(&edmac->lock, flags); | ||
581 | list_for_each_entry_safe(desc, _desc, &edmac->free_list, node) { | ||
582 | if (async_tx_test_ack(&desc->txd)) { | ||
583 | list_del_init(&desc->node); | ||
584 | |||
585 | /* Re-initialize the descriptor */ | ||
586 | desc->src_addr = 0; | ||
587 | desc->dst_addr = 0; | ||
588 | desc->size = 0; | ||
589 | desc->complete = false; | ||
590 | desc->txd.cookie = 0; | ||
591 | desc->txd.callback = NULL; | ||
592 | desc->txd.callback_param = NULL; | ||
593 | |||
594 | ret = desc; | ||
595 | break; | ||
596 | } | ||
597 | } | ||
598 | spin_unlock_irqrestore(&edmac->lock, flags); | ||
599 | return ret; | ||
600 | } | ||
601 | |||
602 | static void ep93xx_dma_desc_put(struct ep93xx_dma_chan *edmac, | ||
603 | struct ep93xx_dma_desc *desc) | ||
604 | { | ||
605 | if (desc) { | ||
606 | unsigned long flags; | ||
607 | |||
608 | spin_lock_irqsave(&edmac->lock, flags); | ||
609 | list_splice_init(&desc->tx_list, &edmac->free_list); | ||
610 | list_add(&desc->node, &edmac->free_list); | ||
611 | spin_unlock_irqrestore(&edmac->lock, flags); | ||
612 | } | ||
613 | } | ||
614 | |||
615 | /** | ||
616 | * ep93xx_dma_advance_work - start processing the next pending transaction | ||
617 | * @edmac: channel | ||
618 | * | ||
619 | * If we have pending transactions queued and we are currently idling, this | ||
620 | * function takes the next queued transaction from the @edmac->queue and | ||
621 | * pushes it to the hardware for execution. | ||
622 | */ | ||
623 | static void ep93xx_dma_advance_work(struct ep93xx_dma_chan *edmac) | ||
624 | { | ||
625 | struct ep93xx_dma_desc *new; | ||
626 | unsigned long flags; | ||
627 | |||
628 | spin_lock_irqsave(&edmac->lock, flags); | ||
629 | if (!list_empty(&edmac->active) || list_empty(&edmac->queue)) { | ||
630 | spin_unlock_irqrestore(&edmac->lock, flags); | ||
631 | return; | ||
632 | } | ||
633 | |||
634 | /* Take the next descriptor from the pending queue */ | ||
635 | new = list_first_entry(&edmac->queue, struct ep93xx_dma_desc, node); | ||
636 | list_del_init(&new->node); | ||
637 | |||
638 | ep93xx_dma_set_active(edmac, new); | ||
639 | |||
640 | /* Push it to the hardware */ | ||
641 | edmac->edma->hw_submit(edmac); | ||
642 | spin_unlock_irqrestore(&edmac->lock, flags); | ||
643 | } | ||
644 | |||
645 | static void ep93xx_dma_unmap_buffers(struct ep93xx_dma_desc *desc) | ||
646 | { | ||
647 | struct device *dev = desc->txd.chan->device->dev; | ||
648 | |||
649 | if (!(desc->txd.flags & DMA_COMPL_SKIP_SRC_UNMAP)) { | ||
650 | if (desc->txd.flags & DMA_COMPL_SRC_UNMAP_SINGLE) | ||
651 | dma_unmap_single(dev, desc->src_addr, desc->size, | ||
652 | DMA_TO_DEVICE); | ||
653 | else | ||
654 | dma_unmap_page(dev, desc->src_addr, desc->size, | ||
655 | DMA_TO_DEVICE); | ||
656 | } | ||
657 | if (!(desc->txd.flags & DMA_COMPL_SKIP_DEST_UNMAP)) { | ||
658 | if (desc->txd.flags & DMA_COMPL_DEST_UNMAP_SINGLE) | ||
659 | dma_unmap_single(dev, desc->dst_addr, desc->size, | ||
660 | DMA_FROM_DEVICE); | ||
661 | else | ||
662 | dma_unmap_page(dev, desc->dst_addr, desc->size, | ||
663 | DMA_FROM_DEVICE); | ||
664 | } | ||
665 | } | ||
666 | |||
667 | static void ep93xx_dma_tasklet(unsigned long data) | ||
668 | { | ||
669 | struct ep93xx_dma_chan *edmac = (struct ep93xx_dma_chan *)data; | ||
670 | struct ep93xx_dma_desc *desc, *d; | ||
671 | dma_async_tx_callback callback; | ||
672 | void *callback_param; | ||
673 | LIST_HEAD(list); | ||
674 | |||
675 | spin_lock_irq(&edmac->lock); | ||
676 | desc = ep93xx_dma_get_active(edmac); | ||
677 | if (desc->complete) { | ||
678 | edmac->last_completed = desc->txd.cookie; | ||
679 | list_splice_init(&edmac->active, &list); | ||
680 | } | ||
681 | spin_unlock_irq(&edmac->lock); | ||
682 | |||
683 | /* Pick up the next descriptor from the queue */ | ||
684 | ep93xx_dma_advance_work(edmac); | ||
685 | |||
686 | callback = desc->txd.callback; | ||
687 | callback_param = desc->txd.callback_param; | ||
688 | |||
689 | /* Now we can release all the chained descriptors */ | ||
690 | list_for_each_entry_safe(desc, d, &list, node) { | ||
691 | /* | ||
692 | * For the memcpy channels the API requires us to unmap the | ||
693 | * buffers unless requested otherwise. | ||
694 | */ | ||
695 | if (!edmac->chan.private) | ||
696 | ep93xx_dma_unmap_buffers(desc); | ||
697 | |||
698 | ep93xx_dma_desc_put(edmac, desc); | ||
699 | } | ||
700 | |||
701 | if (callback) | ||
702 | callback(callback_param); | ||
703 | } | ||
704 | |||
705 | static irqreturn_t ep93xx_dma_interrupt(int irq, void *dev_id) | ||
706 | { | ||
707 | struct ep93xx_dma_chan *edmac = dev_id; | ||
708 | irqreturn_t ret = IRQ_HANDLED; | ||
709 | |||
710 | spin_lock(&edmac->lock); | ||
711 | |||
712 | switch (edmac->edma->hw_interrupt(edmac)) { | ||
713 | case INTERRUPT_DONE: | ||
714 | ep93xx_dma_get_active(edmac)->complete = true; | ||
715 | tasklet_schedule(&edmac->tasklet); | ||
716 | break; | ||
717 | |||
718 | case INTERRUPT_NEXT_BUFFER: | ||
719 | if (test_bit(EP93XX_DMA_IS_CYCLIC, &edmac->flags)) | ||
720 | tasklet_schedule(&edmac->tasklet); | ||
721 | break; | ||
722 | |||
723 | default: | ||
724 | dev_warn(chan2dev(edmac), "unknown interrupt!\n"); | ||
725 | ret = IRQ_NONE; | ||
726 | break; | ||
727 | } | ||
728 | |||
729 | spin_unlock(&edmac->lock); | ||
730 | return ret; | ||
731 | } | ||
732 | |||
733 | /** | ||
734 | * ep93xx_dma_tx_submit - set the prepared descriptor(s) to be executed | ||
735 | * @tx: descriptor to be executed | ||
736 | * | ||
737 | * Function will execute given descriptor on the hardware or if the hardware | ||
738 | * is busy, queue the descriptor to be executed later on. Returns cookie which | ||
739 | * can be used to poll the status of the descriptor. | ||
740 | */ | ||
741 | static dma_cookie_t ep93xx_dma_tx_submit(struct dma_async_tx_descriptor *tx) | ||
742 | { | ||
743 | struct ep93xx_dma_chan *edmac = to_ep93xx_dma_chan(tx->chan); | ||
744 | struct ep93xx_dma_desc *desc; | ||
745 | dma_cookie_t cookie; | ||
746 | unsigned long flags; | ||
747 | |||
748 | spin_lock_irqsave(&edmac->lock, flags); | ||
749 | |||
750 | cookie = edmac->chan.cookie; | ||
751 | |||
752 | if (++cookie < 0) | ||
753 | cookie = 1; | ||
754 | |||
755 | desc = container_of(tx, struct ep93xx_dma_desc, txd); | ||
756 | |||
757 | edmac->chan.cookie = cookie; | ||
758 | desc->txd.cookie = cookie; | ||
759 | |||
760 | /* | ||
761 | * If nothing is currently prosessed, we push this descriptor | ||
762 | * directly to the hardware. Otherwise we put the descriptor | ||
763 | * to the pending queue. | ||
764 | */ | ||
765 | if (list_empty(&edmac->active)) { | ||
766 | ep93xx_dma_set_active(edmac, desc); | ||
767 | edmac->edma->hw_submit(edmac); | ||
768 | } else { | ||
769 | list_add_tail(&desc->node, &edmac->queue); | ||
770 | } | ||
771 | |||
772 | spin_unlock_irqrestore(&edmac->lock, flags); | ||
773 | return cookie; | ||
774 | } | ||
775 | |||
776 | /** | ||
777 | * ep93xx_dma_alloc_chan_resources - allocate resources for the channel | ||
778 | * @chan: channel to allocate resources | ||
779 | * | ||
780 | * Function allocates necessary resources for the given DMA channel and | ||
781 | * returns number of allocated descriptors for the channel. Negative errno | ||
782 | * is returned in case of failure. | ||
783 | */ | ||
784 | static int ep93xx_dma_alloc_chan_resources(struct dma_chan *chan) | ||
785 | { | ||
786 | struct ep93xx_dma_chan *edmac = to_ep93xx_dma_chan(chan); | ||
787 | struct ep93xx_dma_data *data = chan->private; | ||
788 | const char *name = dma_chan_name(chan); | ||
789 | int ret, i; | ||
790 | |||
791 | /* Sanity check the channel parameters */ | ||
792 | if (!edmac->edma->m2m) { | ||
793 | if (!data) | ||
794 | return -EINVAL; | ||
795 | if (data->port < EP93XX_DMA_I2S1 || | ||
796 | data->port > EP93XX_DMA_IRDA) | ||
797 | return -EINVAL; | ||
798 | if (data->direction != ep93xx_dma_chan_direction(chan)) | ||
799 | return -EINVAL; | ||
800 | } else { | ||
801 | if (data) { | ||
802 | switch (data->port) { | ||
803 | case EP93XX_DMA_SSP: | ||
804 | case EP93XX_DMA_IDE: | ||
805 | if (data->direction != DMA_TO_DEVICE && | ||
806 | data->direction != DMA_FROM_DEVICE) | ||
807 | return -EINVAL; | ||
808 | break; | ||
809 | default: | ||
810 | return -EINVAL; | ||
811 | } | ||
812 | } | ||
813 | } | ||
814 | |||
815 | if (data && data->name) | ||
816 | name = data->name; | ||
817 | |||
818 | ret = clk_enable(edmac->clk); | ||
819 | if (ret) | ||
820 | return ret; | ||
821 | |||
822 | ret = request_irq(edmac->irq, ep93xx_dma_interrupt, 0, name, edmac); | ||
823 | if (ret) | ||
824 | goto fail_clk_disable; | ||
825 | |||
826 | spin_lock_irq(&edmac->lock); | ||
827 | edmac->last_completed = 1; | ||
828 | edmac->chan.cookie = 1; | ||
829 | ret = edmac->edma->hw_setup(edmac); | ||
830 | spin_unlock_irq(&edmac->lock); | ||
831 | |||
832 | if (ret) | ||
833 | goto fail_free_irq; | ||
834 | |||
835 | for (i = 0; i < DMA_MAX_CHAN_DESCRIPTORS; i++) { | ||
836 | struct ep93xx_dma_desc *desc; | ||
837 | |||
838 | desc = kzalloc(sizeof(*desc), GFP_KERNEL); | ||
839 | if (!desc) { | ||
840 | dev_warn(chan2dev(edmac), "not enough descriptors\n"); | ||
841 | break; | ||
842 | } | ||
843 | |||
844 | INIT_LIST_HEAD(&desc->tx_list); | ||
845 | |||
846 | dma_async_tx_descriptor_init(&desc->txd, chan); | ||
847 | desc->txd.flags = DMA_CTRL_ACK; | ||
848 | desc->txd.tx_submit = ep93xx_dma_tx_submit; | ||
849 | |||
850 | ep93xx_dma_desc_put(edmac, desc); | ||
851 | } | ||
852 | |||
853 | return i; | ||
854 | |||
855 | fail_free_irq: | ||
856 | free_irq(edmac->irq, edmac); | ||
857 | fail_clk_disable: | ||
858 | clk_disable(edmac->clk); | ||
859 | |||
860 | return ret; | ||
861 | } | ||
862 | |||
863 | /** | ||
864 | * ep93xx_dma_free_chan_resources - release resources for the channel | ||
865 | * @chan: channel | ||
866 | * | ||
867 | * Function releases all the resources allocated for the given channel. | ||
868 | * The channel must be idle when this is called. | ||
869 | */ | ||
870 | static void ep93xx_dma_free_chan_resources(struct dma_chan *chan) | ||
871 | { | ||
872 | struct ep93xx_dma_chan *edmac = to_ep93xx_dma_chan(chan); | ||
873 | struct ep93xx_dma_desc *desc, *d; | ||
874 | unsigned long flags; | ||
875 | LIST_HEAD(list); | ||
876 | |||
877 | BUG_ON(!list_empty(&edmac->active)); | ||
878 | BUG_ON(!list_empty(&edmac->queue)); | ||
879 | |||
880 | spin_lock_irqsave(&edmac->lock, flags); | ||
881 | edmac->edma->hw_shutdown(edmac); | ||
882 | edmac->runtime_addr = 0; | ||
883 | edmac->runtime_ctrl = 0; | ||
884 | edmac->buffer = 0; | ||
885 | list_splice_init(&edmac->free_list, &list); | ||
886 | spin_unlock_irqrestore(&edmac->lock, flags); | ||
887 | |||
888 | list_for_each_entry_safe(desc, d, &list, node) | ||
889 | kfree(desc); | ||
890 | |||
891 | clk_disable(edmac->clk); | ||
892 | free_irq(edmac->irq, edmac); | ||
893 | } | ||
894 | |||
895 | /** | ||
896 | * ep93xx_dma_prep_dma_memcpy - prepare a memcpy DMA operation | ||
897 | * @chan: channel | ||
898 | * @dest: destination bus address | ||
899 | * @src: source bus address | ||
900 | * @len: size of the transaction | ||
901 | * @flags: flags for the descriptor | ||
902 | * | ||
903 | * Returns a valid DMA descriptor or %NULL in case of failure. | ||
904 | */ | ||
905 | struct dma_async_tx_descriptor * | ||
906 | ep93xx_dma_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, | ||
907 | dma_addr_t src, size_t len, unsigned long flags) | ||
908 | { | ||
909 | struct ep93xx_dma_chan *edmac = to_ep93xx_dma_chan(chan); | ||
910 | struct ep93xx_dma_desc *desc, *first; | ||
911 | size_t bytes, offset; | ||
912 | |||
913 | first = NULL; | ||
914 | for (offset = 0; offset < len; offset += bytes) { | ||
915 | desc = ep93xx_dma_desc_get(edmac); | ||
916 | if (!desc) { | ||
917 | dev_warn(chan2dev(edmac), "couln't get descriptor\n"); | ||
918 | goto fail; | ||
919 | } | ||
920 | |||
921 | bytes = min_t(size_t, len - offset, DMA_MAX_CHAN_BYTES); | ||
922 | |||
923 | desc->src_addr = src + offset; | ||
924 | desc->dst_addr = dest + offset; | ||
925 | desc->size = bytes; | ||
926 | |||
927 | if (!first) | ||
928 | first = desc; | ||
929 | else | ||
930 | list_add_tail(&desc->node, &first->tx_list); | ||
931 | } | ||
932 | |||
933 | first->txd.cookie = -EBUSY; | ||
934 | first->txd.flags = flags; | ||
935 | |||
936 | return &first->txd; | ||
937 | fail: | ||
938 | ep93xx_dma_desc_put(edmac, first); | ||
939 | return NULL; | ||
940 | } | ||
941 | |||
942 | /** | ||
943 | * ep93xx_dma_prep_slave_sg - prepare a slave DMA operation | ||
944 | * @chan: channel | ||
945 | * @sgl: list of buffers to transfer | ||
946 | * @sg_len: number of entries in @sgl | ||
947 | * @dir: direction of tha DMA transfer | ||
948 | * @flags: flags for the descriptor | ||
949 | * | ||
950 | * Returns a valid DMA descriptor or %NULL in case of failure. | ||
951 | */ | ||
952 | static struct dma_async_tx_descriptor * | ||
953 | ep93xx_dma_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, | ||
954 | unsigned int sg_len, enum dma_data_direction dir, | ||
955 | unsigned long flags) | ||
956 | { | ||
957 | struct ep93xx_dma_chan *edmac = to_ep93xx_dma_chan(chan); | ||
958 | struct ep93xx_dma_desc *desc, *first; | ||
959 | struct scatterlist *sg; | ||
960 | int i; | ||
961 | |||
962 | if (!edmac->edma->m2m && dir != ep93xx_dma_chan_direction(chan)) { | ||
963 | dev_warn(chan2dev(edmac), | ||
964 | "channel was configured with different direction\n"); | ||
965 | return NULL; | ||
966 | } | ||
967 | |||
968 | if (test_bit(EP93XX_DMA_IS_CYCLIC, &edmac->flags)) { | ||
969 | dev_warn(chan2dev(edmac), | ||
970 | "channel is already used for cyclic transfers\n"); | ||
971 | return NULL; | ||
972 | } | ||
973 | |||
974 | first = NULL; | ||
975 | for_each_sg(sgl, sg, sg_len, i) { | ||
976 | size_t sg_len = sg_dma_len(sg); | ||
977 | |||
978 | if (sg_len > DMA_MAX_CHAN_BYTES) { | ||
979 | dev_warn(chan2dev(edmac), "too big transfer size %d\n", | ||
980 | sg_len); | ||
981 | goto fail; | ||
982 | } | ||
983 | |||
984 | desc = ep93xx_dma_desc_get(edmac); | ||
985 | if (!desc) { | ||
986 | dev_warn(chan2dev(edmac), "couln't get descriptor\n"); | ||
987 | goto fail; | ||
988 | } | ||
989 | |||
990 | if (dir == DMA_TO_DEVICE) { | ||
991 | desc->src_addr = sg_dma_address(sg); | ||
992 | desc->dst_addr = edmac->runtime_addr; | ||
993 | } else { | ||
994 | desc->src_addr = edmac->runtime_addr; | ||
995 | desc->dst_addr = sg_dma_address(sg); | ||
996 | } | ||
997 | desc->size = sg_len; | ||
998 | |||
999 | if (!first) | ||
1000 | first = desc; | ||
1001 | else | ||
1002 | list_add_tail(&desc->node, &first->tx_list); | ||
1003 | } | ||
1004 | |||
1005 | first->txd.cookie = -EBUSY; | ||
1006 | first->txd.flags = flags; | ||
1007 | |||
1008 | return &first->txd; | ||
1009 | |||
1010 | fail: | ||
1011 | ep93xx_dma_desc_put(edmac, first); | ||
1012 | return NULL; | ||
1013 | } | ||
1014 | |||
1015 | /** | ||
1016 | * ep93xx_dma_prep_dma_cyclic - prepare a cyclic DMA operation | ||
1017 | * @chan: channel | ||
1018 | * @dma_addr: DMA mapped address of the buffer | ||
1019 | * @buf_len: length of the buffer (in bytes) | ||
1020 | * @period_len: lenght of a single period | ||
1021 | * @dir: direction of the operation | ||
1022 | * | ||
1023 | * Prepares a descriptor for cyclic DMA operation. This means that once the | ||
1024 | * descriptor is submitted, we will be submitting in a @period_len sized | ||
1025 | * buffers and calling callback once the period has been elapsed. Transfer | ||
1026 | * terminates only when client calls dmaengine_terminate_all() for this | ||
1027 | * channel. | ||
1028 | * | ||
1029 | * Returns a valid DMA descriptor or %NULL in case of failure. | ||
1030 | */ | ||
1031 | static struct dma_async_tx_descriptor * | ||
1032 | ep93xx_dma_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t dma_addr, | ||
1033 | size_t buf_len, size_t period_len, | ||
1034 | enum dma_data_direction dir) | ||
1035 | { | ||
1036 | struct ep93xx_dma_chan *edmac = to_ep93xx_dma_chan(chan); | ||
1037 | struct ep93xx_dma_desc *desc, *first; | ||
1038 | size_t offset = 0; | ||
1039 | |||
1040 | if (!edmac->edma->m2m && dir != ep93xx_dma_chan_direction(chan)) { | ||
1041 | dev_warn(chan2dev(edmac), | ||
1042 | "channel was configured with different direction\n"); | ||
1043 | return NULL; | ||
1044 | } | ||
1045 | |||
1046 | if (test_and_set_bit(EP93XX_DMA_IS_CYCLIC, &edmac->flags)) { | ||
1047 | dev_warn(chan2dev(edmac), | ||
1048 | "channel is already used for cyclic transfers\n"); | ||
1049 | return NULL; | ||
1050 | } | ||
1051 | |||
1052 | if (period_len > DMA_MAX_CHAN_BYTES) { | ||
1053 | dev_warn(chan2dev(edmac), "too big period length %d\n", | ||
1054 | period_len); | ||
1055 | return NULL; | ||
1056 | } | ||
1057 | |||
1058 | /* Split the buffer into period size chunks */ | ||
1059 | first = NULL; | ||
1060 | for (offset = 0; offset < buf_len; offset += period_len) { | ||
1061 | desc = ep93xx_dma_desc_get(edmac); | ||
1062 | if (!desc) { | ||
1063 | dev_warn(chan2dev(edmac), "couln't get descriptor\n"); | ||
1064 | goto fail; | ||
1065 | } | ||
1066 | |||
1067 | if (dir == DMA_TO_DEVICE) { | ||
1068 | desc->src_addr = dma_addr + offset; | ||
1069 | desc->dst_addr = edmac->runtime_addr; | ||
1070 | } else { | ||
1071 | desc->src_addr = edmac->runtime_addr; | ||
1072 | desc->dst_addr = dma_addr + offset; | ||
1073 | } | ||
1074 | |||
1075 | desc->size = period_len; | ||
1076 | |||
1077 | if (!first) | ||
1078 | first = desc; | ||
1079 | else | ||
1080 | list_add_tail(&desc->node, &first->tx_list); | ||
1081 | } | ||
1082 | |||
1083 | first->txd.cookie = -EBUSY; | ||
1084 | |||
1085 | return &first->txd; | ||
1086 | |||
1087 | fail: | ||
1088 | ep93xx_dma_desc_put(edmac, first); | ||
1089 | return NULL; | ||
1090 | } | ||
1091 | |||
1092 | /** | ||
1093 | * ep93xx_dma_terminate_all - terminate all transactions | ||
1094 | * @edmac: channel | ||
1095 | * | ||
1096 | * Stops all DMA transactions. All descriptors are put back to the | ||
1097 | * @edmac->free_list and callbacks are _not_ called. | ||
1098 | */ | ||
1099 | static int ep93xx_dma_terminate_all(struct ep93xx_dma_chan *edmac) | ||
1100 | { | ||
1101 | struct ep93xx_dma_desc *desc, *_d; | ||
1102 | unsigned long flags; | ||
1103 | LIST_HEAD(list); | ||
1104 | |||
1105 | spin_lock_irqsave(&edmac->lock, flags); | ||
1106 | /* First we disable and flush the DMA channel */ | ||
1107 | edmac->edma->hw_shutdown(edmac); | ||
1108 | clear_bit(EP93XX_DMA_IS_CYCLIC, &edmac->flags); | ||
1109 | list_splice_init(&edmac->active, &list); | ||
1110 | list_splice_init(&edmac->queue, &list); | ||
1111 | /* | ||
1112 | * We then re-enable the channel. This way we can continue submitting | ||
1113 | * the descriptors by just calling ->hw_submit() again. | ||
1114 | */ | ||
1115 | edmac->edma->hw_setup(edmac); | ||
1116 | spin_unlock_irqrestore(&edmac->lock, flags); | ||
1117 | |||
1118 | list_for_each_entry_safe(desc, _d, &list, node) | ||
1119 | ep93xx_dma_desc_put(edmac, desc); | ||
1120 | |||
1121 | return 0; | ||
1122 | } | ||
1123 | |||
1124 | static int ep93xx_dma_slave_config(struct ep93xx_dma_chan *edmac, | ||
1125 | struct dma_slave_config *config) | ||
1126 | { | ||
1127 | enum dma_slave_buswidth width; | ||
1128 | unsigned long flags; | ||
1129 | u32 addr, ctrl; | ||
1130 | |||
1131 | if (!edmac->edma->m2m) | ||
1132 | return -EINVAL; | ||
1133 | |||
1134 | switch (config->direction) { | ||
1135 | case DMA_FROM_DEVICE: | ||
1136 | width = config->src_addr_width; | ||
1137 | addr = config->src_addr; | ||
1138 | break; | ||
1139 | |||
1140 | case DMA_TO_DEVICE: | ||
1141 | width = config->dst_addr_width; | ||
1142 | addr = config->dst_addr; | ||
1143 | break; | ||
1144 | |||
1145 | default: | ||
1146 | return -EINVAL; | ||
1147 | } | ||
1148 | |||
1149 | switch (width) { | ||
1150 | case DMA_SLAVE_BUSWIDTH_1_BYTE: | ||
1151 | ctrl = 0; | ||
1152 | break; | ||
1153 | case DMA_SLAVE_BUSWIDTH_2_BYTES: | ||
1154 | ctrl = M2M_CONTROL_PW_16; | ||
1155 | break; | ||
1156 | case DMA_SLAVE_BUSWIDTH_4_BYTES: | ||
1157 | ctrl = M2M_CONTROL_PW_32; | ||
1158 | break; | ||
1159 | default: | ||
1160 | return -EINVAL; | ||
1161 | } | ||
1162 | |||
1163 | spin_lock_irqsave(&edmac->lock, flags); | ||
1164 | edmac->runtime_addr = addr; | ||
1165 | edmac->runtime_ctrl = ctrl; | ||
1166 | spin_unlock_irqrestore(&edmac->lock, flags); | ||
1167 | |||
1168 | return 0; | ||
1169 | } | ||
1170 | |||
1171 | /** | ||
1172 | * ep93xx_dma_control - manipulate all pending operations on a channel | ||
1173 | * @chan: channel | ||
1174 | * @cmd: control command to perform | ||
1175 | * @arg: optional argument | ||
1176 | * | ||
1177 | * Controls the channel. Function returns %0 in case of success or negative | ||
1178 | * error in case of failure. | ||
1179 | */ | ||
1180 | static int ep93xx_dma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, | ||
1181 | unsigned long arg) | ||
1182 | { | ||
1183 | struct ep93xx_dma_chan *edmac = to_ep93xx_dma_chan(chan); | ||
1184 | struct dma_slave_config *config; | ||
1185 | |||
1186 | switch (cmd) { | ||
1187 | case DMA_TERMINATE_ALL: | ||
1188 | return ep93xx_dma_terminate_all(edmac); | ||
1189 | |||
1190 | case DMA_SLAVE_CONFIG: | ||
1191 | config = (struct dma_slave_config *)arg; | ||
1192 | return ep93xx_dma_slave_config(edmac, config); | ||
1193 | |||
1194 | default: | ||
1195 | break; | ||
1196 | } | ||
1197 | |||
1198 | return -ENOSYS; | ||
1199 | } | ||
1200 | |||
1201 | /** | ||
1202 | * ep93xx_dma_tx_status - check if a transaction is completed | ||
1203 | * @chan: channel | ||
1204 | * @cookie: transaction specific cookie | ||
1205 | * @state: state of the transaction is stored here if given | ||
1206 | * | ||
1207 | * This function can be used to query state of a given transaction. | ||
1208 | */ | ||
1209 | static enum dma_status ep93xx_dma_tx_status(struct dma_chan *chan, | ||
1210 | dma_cookie_t cookie, | ||
1211 | struct dma_tx_state *state) | ||
1212 | { | ||
1213 | struct ep93xx_dma_chan *edmac = to_ep93xx_dma_chan(chan); | ||
1214 | dma_cookie_t last_used, last_completed; | ||
1215 | enum dma_status ret; | ||
1216 | unsigned long flags; | ||
1217 | |||
1218 | spin_lock_irqsave(&edmac->lock, flags); | ||
1219 | last_used = chan->cookie; | ||
1220 | last_completed = edmac->last_completed; | ||
1221 | spin_unlock_irqrestore(&edmac->lock, flags); | ||
1222 | |||
1223 | ret = dma_async_is_complete(cookie, last_completed, last_used); | ||
1224 | dma_set_tx_state(state, last_completed, last_used, 0); | ||
1225 | |||
1226 | return ret; | ||
1227 | } | ||
1228 | |||
1229 | /** | ||
1230 | * ep93xx_dma_issue_pending - push pending transactions to the hardware | ||
1231 | * @chan: channel | ||
1232 | * | ||
1233 | * When this function is called, all pending transactions are pushed to the | ||
1234 | * hardware and executed. | ||
1235 | */ | ||
1236 | static void ep93xx_dma_issue_pending(struct dma_chan *chan) | ||
1237 | { | ||
1238 | ep93xx_dma_advance_work(to_ep93xx_dma_chan(chan)); | ||
1239 | } | ||
1240 | |||
1241 | static int __init ep93xx_dma_probe(struct platform_device *pdev) | ||
1242 | { | ||
1243 | struct ep93xx_dma_platform_data *pdata = dev_get_platdata(&pdev->dev); | ||
1244 | struct ep93xx_dma_engine *edma; | ||
1245 | struct dma_device *dma_dev; | ||
1246 | size_t edma_size; | ||
1247 | int ret, i; | ||
1248 | |||
1249 | edma_size = pdata->num_channels * sizeof(struct ep93xx_dma_chan); | ||
1250 | edma = kzalloc(sizeof(*edma) + edma_size, GFP_KERNEL); | ||
1251 | if (!edma) | ||
1252 | return -ENOMEM; | ||
1253 | |||
1254 | dma_dev = &edma->dma_dev; | ||
1255 | edma->m2m = platform_get_device_id(pdev)->driver_data; | ||
1256 | edma->num_channels = pdata->num_channels; | ||
1257 | |||
1258 | INIT_LIST_HEAD(&dma_dev->channels); | ||
1259 | for (i = 0; i < pdata->num_channels; i++) { | ||
1260 | const struct ep93xx_dma_chan_data *cdata = &pdata->channels[i]; | ||
1261 | struct ep93xx_dma_chan *edmac = &edma->channels[i]; | ||
1262 | |||
1263 | edmac->chan.device = dma_dev; | ||
1264 | edmac->regs = cdata->base; | ||
1265 | edmac->irq = cdata->irq; | ||
1266 | edmac->edma = edma; | ||
1267 | |||
1268 | edmac->clk = clk_get(NULL, cdata->name); | ||
1269 | if (IS_ERR(edmac->clk)) { | ||
1270 | dev_warn(&pdev->dev, "failed to get clock for %s\n", | ||
1271 | cdata->name); | ||
1272 | continue; | ||
1273 | } | ||
1274 | |||
1275 | spin_lock_init(&edmac->lock); | ||
1276 | INIT_LIST_HEAD(&edmac->active); | ||
1277 | INIT_LIST_HEAD(&edmac->queue); | ||
1278 | INIT_LIST_HEAD(&edmac->free_list); | ||
1279 | tasklet_init(&edmac->tasklet, ep93xx_dma_tasklet, | ||
1280 | (unsigned long)edmac); | ||
1281 | |||
1282 | list_add_tail(&edmac->chan.device_node, | ||
1283 | &dma_dev->channels); | ||
1284 | } | ||
1285 | |||
1286 | dma_cap_zero(dma_dev->cap_mask); | ||
1287 | dma_cap_set(DMA_SLAVE, dma_dev->cap_mask); | ||
1288 | dma_cap_set(DMA_CYCLIC, dma_dev->cap_mask); | ||
1289 | |||
1290 | dma_dev->dev = &pdev->dev; | ||
1291 | dma_dev->device_alloc_chan_resources = ep93xx_dma_alloc_chan_resources; | ||
1292 | dma_dev->device_free_chan_resources = ep93xx_dma_free_chan_resources; | ||
1293 | dma_dev->device_prep_slave_sg = ep93xx_dma_prep_slave_sg; | ||
1294 | dma_dev->device_prep_dma_cyclic = ep93xx_dma_prep_dma_cyclic; | ||
1295 | dma_dev->device_control = ep93xx_dma_control; | ||
1296 | dma_dev->device_issue_pending = ep93xx_dma_issue_pending; | ||
1297 | dma_dev->device_tx_status = ep93xx_dma_tx_status; | ||
1298 | |||
1299 | dma_set_max_seg_size(dma_dev->dev, DMA_MAX_CHAN_BYTES); | ||
1300 | |||
1301 | if (edma->m2m) { | ||
1302 | dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask); | ||
1303 | dma_dev->device_prep_dma_memcpy = ep93xx_dma_prep_dma_memcpy; | ||
1304 | |||
1305 | edma->hw_setup = m2m_hw_setup; | ||
1306 | edma->hw_shutdown = m2m_hw_shutdown; | ||
1307 | edma->hw_submit = m2m_hw_submit; | ||
1308 | edma->hw_interrupt = m2m_hw_interrupt; | ||
1309 | } else { | ||
1310 | dma_cap_set(DMA_PRIVATE, dma_dev->cap_mask); | ||
1311 | |||
1312 | edma->hw_setup = m2p_hw_setup; | ||
1313 | edma->hw_shutdown = m2p_hw_shutdown; | ||
1314 | edma->hw_submit = m2p_hw_submit; | ||
1315 | edma->hw_interrupt = m2p_hw_interrupt; | ||
1316 | } | ||
1317 | |||
1318 | ret = dma_async_device_register(dma_dev); | ||
1319 | if (unlikely(ret)) { | ||
1320 | for (i = 0; i < edma->num_channels; i++) { | ||
1321 | struct ep93xx_dma_chan *edmac = &edma->channels[i]; | ||
1322 | if (!IS_ERR_OR_NULL(edmac->clk)) | ||
1323 | clk_put(edmac->clk); | ||
1324 | } | ||
1325 | kfree(edma); | ||
1326 | } else { | ||
1327 | dev_info(dma_dev->dev, "EP93xx M2%s DMA ready\n", | ||
1328 | edma->m2m ? "M" : "P"); | ||
1329 | } | ||
1330 | |||
1331 | return ret; | ||
1332 | } | ||
1333 | |||
1334 | static struct platform_device_id ep93xx_dma_driver_ids[] = { | ||
1335 | { "ep93xx-dma-m2p", 0 }, | ||
1336 | { "ep93xx-dma-m2m", 1 }, | ||
1337 | { }, | ||
1338 | }; | ||
1339 | |||
1340 | static struct platform_driver ep93xx_dma_driver = { | ||
1341 | .driver = { | ||
1342 | .name = "ep93xx-dma", | ||
1343 | }, | ||
1344 | .id_table = ep93xx_dma_driver_ids, | ||
1345 | }; | ||
1346 | |||
1347 | static int __init ep93xx_dma_module_init(void) | ||
1348 | { | ||
1349 | return platform_driver_probe(&ep93xx_dma_driver, ep93xx_dma_probe); | ||
1350 | } | ||
1351 | subsys_initcall(ep93xx_dma_module_init); | ||
1352 | |||
1353 | MODULE_AUTHOR("Mika Westerberg <mika.westerberg@iki.fi>"); | ||
1354 | MODULE_DESCRIPTION("EP93xx DMA driver"); | ||
1355 | MODULE_LICENSE("GPL"); | ||