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authorShawn Guo <shawn.guo@freescale.com>2011-02-26 11:47:42 -0500
committerVinod Koul <vinod.koul@intel.com>2011-03-01 20:36:27 -0500
commita580b8c5429a624d120cd603e1498bf676e2b4da (patch)
tree14e4bd82f203bf9f43fa19341d85d993e5a4c569
parent26d890f0d09fd58f7194aad651e86283cb9e6574 (diff)
dmaengine: mxs-dma: add dma support for i.MX23/28
This patch adds dma support for Freescale MXS-based SoC i.MX23/28, including apbh-dma and apbx-dma. * apbh-dma and apbx-dma are supported in the driver as two mxs-dma instances. * apbh-dma is different between mx23 and mx28, hardware version register is used to differentiate. * mxs-dma supports pio function besides data transfer. The driver uses dma_data_direction DMA_NONE to identify the pio mode, and steals sgl and sg_len to get pio words and numbers from clients. * mxs dmaengine has some very specific features, like sense function and the special NAND support (nand_lock, nand_wait4ready). These are too specific to implemented in generic dmaengine driver. * The driver refers to imx-sdma and only a single descriptor is statically assigned to each channel. Signed-off-by: Shawn Guo <shawn.guo@freescale.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Diffstat
-rw-r--r--arch/arm/mach-mxs/include/mach/dma.h26
-rw-r--r--drivers/dma/Kconfig8
-rw-r--r--drivers/dma/Makefile1
-rw-r--r--drivers/dma/mxs-dma.c724
4 files changed, 759 insertions, 0 deletions
diff --git a/arch/arm/mach-mxs/include/mach/dma.h b/arch/arm/mach-mxs/include/mach/dma.h
new file mode 100644
index 000000000000..7f4aeeaba8df
--- /dev/null
+++ b/arch/arm/mach-mxs/include/mach/dma.h
@@ -0,0 +1,26 @@
1/*
2 * Copyright 2011 Freescale Semiconductor, Inc. All Rights Reserved.
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 */
8
9#ifndef __MACH_MXS_DMA_H__
10#define __MACH_MXS_DMA_H__
11
12struct mxs_dma_data {
13 int chan_irq;
14};
15
16static inline int mxs_dma_is_apbh(struct dma_chan *chan)
17{
18 return !strcmp(dev_name(chan->device->dev), "mxs-dma-apbh");
19}
20
21static inline int mxs_dma_is_apbx(struct dma_chan *chan)
22{
23 return !strcmp(dev_name(chan->device->dev), "mxs-dma-apbx");
24}
25
26#endif /* __MACH_MXS_DMA_H__ */
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index 1c28816152fa..76f6472ba315 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -227,6 +227,14 @@ config IMX_DMA
227 Support the i.MX DMA engine. This engine is integrated into 227 Support the i.MX DMA engine. This engine is integrated into
228 Freescale i.MX1/21/27 chips. 228 Freescale i.MX1/21/27 chips.
229 229
230config MXS_DMA
231 bool "MXS DMA support"
232 depends on SOC_IMX23 || SOC_IMX28
233 select DMA_ENGINE
234 help
235 Support the MXS DMA engine. This engine including APBH-DMA
236 and APBX-DMA is integrated into Freescale i.MX23/28 chips.
237
230config DMA_ENGINE 238config DMA_ENGINE
231 bool 239 bool
232 240
diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
index 64b21f5cd740..802b55795f8b 100644
--- a/drivers/dma/Makefile
+++ b/drivers/dma/Makefile
@@ -23,6 +23,7 @@ obj-$(CONFIG_COH901318) += coh901318.o coh901318_lli.o
23obj-$(CONFIG_AMCC_PPC440SPE_ADMA) += ppc4xx/ 23obj-$(CONFIG_AMCC_PPC440SPE_ADMA) += ppc4xx/
24obj-$(CONFIG_IMX_SDMA) += imx-sdma.o 24obj-$(CONFIG_IMX_SDMA) += imx-sdma.o
25obj-$(CONFIG_IMX_DMA) += imx-dma.o 25obj-$(CONFIG_IMX_DMA) += imx-dma.o
26obj-$(CONFIG_MXS_DMA) += mxs-dma.o
26obj-$(CONFIG_TIMB_DMA) += timb_dma.o 27obj-$(CONFIG_TIMB_DMA) += timb_dma.o
27obj-$(CONFIG_STE_DMA40) += ste_dma40.o ste_dma40_ll.o 28obj-$(CONFIG_STE_DMA40) += ste_dma40.o ste_dma40_ll.o
28obj-$(CONFIG_PL330_DMA) += pl330.o 29obj-$(CONFIG_PL330_DMA) += pl330.o
diff --git a/drivers/dma/mxs-dma.c b/drivers/dma/mxs-dma.c
new file mode 100644
index 000000000000..88aad4f54002
--- /dev/null
+++ b/drivers/dma/mxs-dma.c
@@ -0,0 +1,724 @@
1/*
2 * Copyright 2011 Freescale Semiconductor, Inc. All Rights Reserved.
3 *
4 * Refer to drivers/dma/imx-sdma.c
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11#include <linux/init.h>
12#include <linux/types.h>
13#include <linux/mm.h>
14#include <linux/interrupt.h>
15#include <linux/clk.h>
16#include <linux/wait.h>
17#include <linux/sched.h>
18#include <linux/semaphore.h>
19#include <linux/device.h>
20#include <linux/dma-mapping.h>
21#include <linux/slab.h>
22#include <linux/platform_device.h>
23#include <linux/dmaengine.h>
24#include <linux/delay.h>
25
26#include <asm/irq.h>
27#include <mach/mxs.h>
28#include <mach/dma.h>
29#include <mach/common.h>
30
31/*
32 * NOTE: The term "PIO" throughout the mxs-dma implementation means
33 * PIO mode of mxs apbh-dma and apbx-dma. With this working mode,
34 * dma can program the controller registers of peripheral devices.
35 */
36
37#define MXS_DMA_APBH 0
38#define MXS_DMA_APBX 1
39#define dma_is_apbh() (mxs_dma->dev_id == MXS_DMA_APBH)
40
41#define APBH_VERSION_LATEST 3
42#define apbh_is_old() (mxs_dma->version < APBH_VERSION_LATEST)
43
44#define HW_APBHX_CTRL0 0x000
45#define BM_APBH_CTRL0_APB_BURST8_EN (1 << 29)
46#define BM_APBH_CTRL0_APB_BURST_EN (1 << 28)
47#define BP_APBH_CTRL0_CLKGATE_CHANNEL 8
48#define BP_APBH_CTRL0_RESET_CHANNEL 16
49#define HW_APBHX_CTRL1 0x010
50#define HW_APBHX_CTRL2 0x020
51#define HW_APBHX_CHANNEL_CTRL 0x030
52#define BP_APBHX_CHANNEL_CTRL_RESET_CHANNEL 16
53#define HW_APBH_VERSION (cpu_is_mx23() ? 0x3f0 : 0x800)
54#define HW_APBX_VERSION 0x800
55#define BP_APBHX_VERSION_MAJOR 24
56#define HW_APBHX_CHn_NXTCMDAR(n) \
57 (((dma_is_apbh() && apbh_is_old()) ? 0x050 : 0x110) + (n) * 0x70)
58#define HW_APBHX_CHn_SEMA(n) \
59 (((dma_is_apbh() && apbh_is_old()) ? 0x080 : 0x140) + (n) * 0x70)
60
61/*
62 * ccw bits definitions
63 *
64 * COMMAND: 0..1 (2)
65 * CHAIN: 2 (1)
66 * IRQ: 3 (1)
67 * NAND_LOCK: 4 (1) - not implemented
68 * NAND_WAIT4READY: 5 (1) - not implemented
69 * DEC_SEM: 6 (1)
70 * WAIT4END: 7 (1)
71 * HALT_ON_TERMINATE: 8 (1)
72 * TERMINATE_FLUSH: 9 (1)
73 * RESERVED: 10..11 (2)
74 * PIO_NUM: 12..15 (4)
75 */
76#define BP_CCW_COMMAND 0
77#define BM_CCW_COMMAND (3 << 0)
78#define CCW_CHAIN (1 << 2)
79#define CCW_IRQ (1 << 3)
80#define CCW_DEC_SEM (1 << 6)
81#define CCW_WAIT4END (1 << 7)
82#define CCW_HALT_ON_TERM (1 << 8)
83#define CCW_TERM_FLUSH (1 << 9)
84#define BP_CCW_PIO_NUM 12
85#define BM_CCW_PIO_NUM (0xf << 12)
86
87#define BF_CCW(value, field) (((value) << BP_CCW_##field) & BM_CCW_##field)
88
89#define MXS_DMA_CMD_NO_XFER 0
90#define MXS_DMA_CMD_WRITE 1
91#define MXS_DMA_CMD_READ 2
92#define MXS_DMA_CMD_DMA_SENSE 3 /* not implemented */
93
94struct mxs_dma_ccw {
95 u32 next;
96 u16 bits;
97 u16 xfer_bytes;
98#define MAX_XFER_BYTES 0xff00
99 u32 bufaddr;
100#define MXS_PIO_WORDS 16
101 u32 pio_words[MXS_PIO_WORDS];
102};
103
104#define NUM_CCW (int)(PAGE_SIZE / sizeof(struct mxs_dma_ccw))
105
106struct mxs_dma_chan {
107 struct mxs_dma_engine *mxs_dma;
108 struct dma_chan chan;
109 struct dma_async_tx_descriptor desc;
110 struct tasklet_struct tasklet;
111 int chan_irq;
112 struct mxs_dma_ccw *ccw;
113 dma_addr_t ccw_phys;
114 dma_cookie_t last_completed;
115 enum dma_status status;
116 unsigned int flags;
117#define MXS_DMA_SG_LOOP (1 << 0)
118};
119
120#define MXS_DMA_CHANNELS 16
121#define MXS_DMA_CHANNELS_MASK 0xffff
122
123struct mxs_dma_engine {
124 int dev_id;
125 unsigned int version;
126 void __iomem *base;
127 struct clk *clk;
128 struct dma_device dma_device;
129 struct device_dma_parameters dma_parms;
130 struct mxs_dma_chan mxs_chans[MXS_DMA_CHANNELS];
131};
132
133static void mxs_dma_reset_chan(struct mxs_dma_chan *mxs_chan)
134{
135 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
136 int chan_id = mxs_chan->chan.chan_id;
137
138 if (dma_is_apbh() && apbh_is_old())
139 writel(1 << (chan_id + BP_APBH_CTRL0_RESET_CHANNEL),
140 mxs_dma->base + HW_APBHX_CTRL0 + MXS_SET_ADDR);
141 else
142 writel(1 << (chan_id + BP_APBHX_CHANNEL_CTRL_RESET_CHANNEL),
143 mxs_dma->base + HW_APBHX_CHANNEL_CTRL + MXS_SET_ADDR);
144}
145
146static void mxs_dma_enable_chan(struct mxs_dma_chan *mxs_chan)
147{
148 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
149 int chan_id = mxs_chan->chan.chan_id;
150
151 /* set cmd_addr up */
152 writel(mxs_chan->ccw_phys,
153 mxs_dma->base + HW_APBHX_CHn_NXTCMDAR(chan_id));
154
155 /* enable apbh channel clock */
156 if (dma_is_apbh()) {
157 if (apbh_is_old())
158 writel(1 << (chan_id + BP_APBH_CTRL0_CLKGATE_CHANNEL),
159 mxs_dma->base + HW_APBHX_CTRL0 + MXS_CLR_ADDR);
160 else
161 writel(1 << chan_id,
162 mxs_dma->base + HW_APBHX_CTRL0 + MXS_CLR_ADDR);
163 }
164
165 /* write 1 to SEMA to kick off the channel */
166 writel(1, mxs_dma->base + HW_APBHX_CHn_SEMA(chan_id));
167}
168
169static void mxs_dma_disable_chan(struct mxs_dma_chan *mxs_chan)
170{
171 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
172 int chan_id = mxs_chan->chan.chan_id;
173
174 /* disable apbh channel clock */
175 if (dma_is_apbh()) {
176 if (apbh_is_old())
177 writel(1 << (chan_id + BP_APBH_CTRL0_CLKGATE_CHANNEL),
178 mxs_dma->base + HW_APBHX_CTRL0 + MXS_SET_ADDR);
179 else
180 writel(1 << chan_id,
181 mxs_dma->base + HW_APBHX_CTRL0 + MXS_SET_ADDR);
182 }
183
184 mxs_chan->status = DMA_SUCCESS;
185}
186
187static void mxs_dma_pause_chan(struct mxs_dma_chan *mxs_chan)
188{
189 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
190 int chan_id = mxs_chan->chan.chan_id;
191
192 /* freeze the channel */
193 if (dma_is_apbh() && apbh_is_old())
194 writel(1 << chan_id,
195 mxs_dma->base + HW_APBHX_CTRL0 + MXS_SET_ADDR);
196 else
197 writel(1 << chan_id,
198 mxs_dma->base + HW_APBHX_CHANNEL_CTRL + MXS_SET_ADDR);
199
200 mxs_chan->status = DMA_PAUSED;
201}
202
203static void mxs_dma_resume_chan(struct mxs_dma_chan *mxs_chan)
204{
205 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
206 int chan_id = mxs_chan->chan.chan_id;
207
208 /* unfreeze the channel */
209 if (dma_is_apbh() && apbh_is_old())
210 writel(1 << chan_id,
211 mxs_dma->base + HW_APBHX_CTRL0 + MXS_CLR_ADDR);
212 else
213 writel(1 << chan_id,
214 mxs_dma->base + HW_APBHX_CHANNEL_CTRL + MXS_CLR_ADDR);
215
216 mxs_chan->status = DMA_IN_PROGRESS;
217}
218
219static dma_cookie_t mxs_dma_assign_cookie(struct mxs_dma_chan *mxs_chan)
220{
221 dma_cookie_t cookie = mxs_chan->chan.cookie;
222
223 if (++cookie < 0)
224 cookie = 1;
225
226 mxs_chan->chan.cookie = cookie;
227 mxs_chan->desc.cookie = cookie;
228
229 return cookie;
230}
231
232static struct mxs_dma_chan *to_mxs_dma_chan(struct dma_chan *chan)
233{
234 return container_of(chan, struct mxs_dma_chan, chan);
235}
236
237static dma_cookie_t mxs_dma_tx_submit(struct dma_async_tx_descriptor *tx)
238{
239 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(tx->chan);
240
241 mxs_dma_enable_chan(mxs_chan);
242
243 return mxs_dma_assign_cookie(mxs_chan);
244}
245
246static void mxs_dma_tasklet(unsigned long data)
247{
248 struct mxs_dma_chan *mxs_chan = (struct mxs_dma_chan *) data;
249
250 if (mxs_chan->desc.callback)
251 mxs_chan->desc.callback(mxs_chan->desc.callback_param);
252}
253
254static irqreturn_t mxs_dma_int_handler(int irq, void *dev_id)
255{
256 struct mxs_dma_engine *mxs_dma = dev_id;
257 u32 stat1, stat2;
258
259 /* completion status */
260 stat1 = readl(mxs_dma->base + HW_APBHX_CTRL1);
261 stat1 &= MXS_DMA_CHANNELS_MASK;
262 writel(stat1, mxs_dma->base + HW_APBHX_CTRL1 + MXS_CLR_ADDR);
263
264 /* error status */
265 stat2 = readl(mxs_dma->base + HW_APBHX_CTRL2);
266 writel(stat2, mxs_dma->base + HW_APBHX_CTRL2 + MXS_CLR_ADDR);
267
268 /*
269 * When both completion and error of termination bits set at the
270 * same time, we do not take it as an error. IOW, it only becomes
271 * an error we need to handler here in case of ether it's (1) an bus
272 * error or (2) a termination error with no completion.
273 */
274 stat2 = ((stat2 >> MXS_DMA_CHANNELS) & stat2) | /* (1) */
275 (~(stat2 >> MXS_DMA_CHANNELS) & stat2 & ~stat1); /* (2) */
276
277 /* combine error and completion status for checking */
278 stat1 = (stat2 << MXS_DMA_CHANNELS) | stat1;
279 while (stat1) {
280 int channel = fls(stat1) - 1;
281 struct mxs_dma_chan *mxs_chan =
282 &mxs_dma->mxs_chans[channel % MXS_DMA_CHANNELS];
283
284 if (channel >= MXS_DMA_CHANNELS) {
285 dev_dbg(mxs_dma->dma_device.dev,
286 "%s: error in channel %d\n", __func__,
287 channel - MXS_DMA_CHANNELS);
288 mxs_chan->status = DMA_ERROR;
289 mxs_dma_reset_chan(mxs_chan);
290 } else {
291 if (mxs_chan->flags & MXS_DMA_SG_LOOP)
292 mxs_chan->status = DMA_IN_PROGRESS;
293 else
294 mxs_chan->status = DMA_SUCCESS;
295 }
296
297 stat1 &= ~(1 << channel);
298
299 if (mxs_chan->status == DMA_SUCCESS)
300 mxs_chan->last_completed = mxs_chan->desc.cookie;
301
302 /* schedule tasklet on this channel */
303 tasklet_schedule(&mxs_chan->tasklet);
304 }
305
306 return IRQ_HANDLED;
307}
308
309static int mxs_dma_alloc_chan_resources(struct dma_chan *chan)
310{
311 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
312 struct mxs_dma_data *data = chan->private;
313 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
314 int ret;
315
316 if (!data)
317 return -EINVAL;
318
319 mxs_chan->chan_irq = data->chan_irq;
320
321 mxs_chan->ccw = dma_alloc_coherent(mxs_dma->dma_device.dev, PAGE_SIZE,
322 &mxs_chan->ccw_phys, GFP_KERNEL);
323 if (!mxs_chan->ccw) {
324 ret = -ENOMEM;
325 goto err_alloc;
326 }
327
328 memset(mxs_chan->ccw, 0, PAGE_SIZE);
329
330 ret = request_irq(mxs_chan->chan_irq, mxs_dma_int_handler,
331 0, "mxs-dma", mxs_dma);
332 if (ret)
333 goto err_irq;
334
335 ret = clk_enable(mxs_dma->clk);
336 if (ret)
337 goto err_clk;
338
339 mxs_dma_reset_chan(mxs_chan);
340
341 dma_async_tx_descriptor_init(&mxs_chan->desc, chan);
342 mxs_chan->desc.tx_submit = mxs_dma_tx_submit;
343
344 /* the descriptor is ready */
345 async_tx_ack(&mxs_chan->desc);
346
347 return 0;
348
349err_clk:
350 free_irq(mxs_chan->chan_irq, mxs_dma);
351err_irq:
352 dma_free_coherent(mxs_dma->dma_device.dev, PAGE_SIZE,
353 mxs_chan->ccw, mxs_chan->ccw_phys);
354err_alloc:
355 return ret;
356}
357
358static void mxs_dma_free_chan_resources(struct dma_chan *chan)
359{
360 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
361 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
362
363 mxs_dma_disable_chan(mxs_chan);
364
365 free_irq(mxs_chan->chan_irq, mxs_dma);
366
367 dma_free_coherent(mxs_dma->dma_device.dev, PAGE_SIZE,
368 mxs_chan->ccw, mxs_chan->ccw_phys);
369
370 clk_disable(mxs_dma->clk);
371}
372
373static struct dma_async_tx_descriptor *mxs_dma_prep_slave_sg(
374 struct dma_chan *chan, struct scatterlist *sgl,
375 unsigned int sg_len, enum dma_data_direction direction,
376 unsigned long append)
377{
378 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
379 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
380 struct mxs_dma_ccw *ccw;
381 struct scatterlist *sg;
382 int i, j;
383 u32 *pio;
384 static int idx;
385
386 if (mxs_chan->status == DMA_IN_PROGRESS && !append)
387 return NULL;
388
389 if (sg_len + (append ? idx : 0) > NUM_CCW) {
390 dev_err(mxs_dma->dma_device.dev,
391 "maximum number of sg exceeded: %d > %d\n",
392 sg_len, NUM_CCW);
393 goto err_out;
394 }
395
396 mxs_chan->status = DMA_IN_PROGRESS;
397 mxs_chan->flags = 0;
398
399 /*
400 * If the sg is prepared with append flag set, the sg
401 * will be appended to the last prepared sg.
402 */
403 if (append) {
404 BUG_ON(idx < 1);
405 ccw = &mxs_chan->ccw[idx - 1];
406 ccw->next = mxs_chan->ccw_phys + sizeof(*ccw) * idx;
407 ccw->bits |= CCW_CHAIN;
408 ccw->bits &= ~CCW_IRQ;
409 ccw->bits &= ~CCW_DEC_SEM;
410 ccw->bits &= ~CCW_WAIT4END;
411 } else {
412 idx = 0;
413 }
414
415 if (direction == DMA_NONE) {
416 ccw = &mxs_chan->ccw[idx++];
417 pio = (u32 *) sgl;
418
419 for (j = 0; j < sg_len;)
420 ccw->pio_words[j++] = *pio++;
421
422 ccw->bits = 0;
423 ccw->bits |= CCW_IRQ;
424 ccw->bits |= CCW_DEC_SEM;
425 ccw->bits |= CCW_WAIT4END;
426 ccw->bits |= CCW_HALT_ON_TERM;
427 ccw->bits |= CCW_TERM_FLUSH;
428 ccw->bits |= BF_CCW(sg_len, PIO_NUM);
429 ccw->bits |= BF_CCW(MXS_DMA_CMD_NO_XFER, COMMAND);
430 } else {
431 for_each_sg(sgl, sg, sg_len, i) {
432 if (sg->length > MAX_XFER_BYTES) {
433 dev_err(mxs_dma->dma_device.dev, "maximum bytes for sg entry exceeded: %d > %d\n",
434 sg->length, MAX_XFER_BYTES);
435 goto err_out;
436 }
437
438 ccw = &mxs_chan->ccw[idx++];
439
440 ccw->next = mxs_chan->ccw_phys + sizeof(*ccw) * idx;
441 ccw->bufaddr = sg->dma_address;
442 ccw->xfer_bytes = sg->length;
443
444 ccw->bits = 0;
445 ccw->bits |= CCW_CHAIN;
446 ccw->bits |= CCW_HALT_ON_TERM;
447 ccw->bits |= CCW_TERM_FLUSH;
448 ccw->bits |= BF_CCW(direction == DMA_FROM_DEVICE ?
449 MXS_DMA_CMD_WRITE : MXS_DMA_CMD_READ,
450 COMMAND);
451
452 if (i + 1 == sg_len) {
453 ccw->bits &= ~CCW_CHAIN;
454 ccw->bits |= CCW_IRQ;
455 ccw->bits |= CCW_DEC_SEM;
456 ccw->bits |= CCW_WAIT4END;
457 }
458 }
459 }
460
461 return &mxs_chan->desc;
462
463err_out:
464 mxs_chan->status = DMA_ERROR;
465 return NULL;
466}
467
468static struct dma_async_tx_descriptor *mxs_dma_prep_dma_cyclic(
469 struct dma_chan *chan, dma_addr_t dma_addr, size_t buf_len,
470 size_t period_len, enum dma_data_direction direction)
471{
472 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
473 struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
474 int num_periods = buf_len / period_len;
475 int i = 0, buf = 0;
476
477 if (mxs_chan->status == DMA_IN_PROGRESS)
478 return NULL;
479
480 mxs_chan->status = DMA_IN_PROGRESS;
481 mxs_chan->flags |= MXS_DMA_SG_LOOP;
482
483 if (num_periods > NUM_CCW) {
484 dev_err(mxs_dma->dma_device.dev,
485 "maximum number of sg exceeded: %d > %d\n",
486 num_periods, NUM_CCW);
487 goto err_out;
488 }
489
490 if (period_len > MAX_XFER_BYTES) {
491 dev_err(mxs_dma->dma_device.dev,
492 "maximum period size exceeded: %d > %d\n",
493 period_len, MAX_XFER_BYTES);
494 goto err_out;
495 }
496
497 while (buf < buf_len) {
498 struct mxs_dma_ccw *ccw = &mxs_chan->ccw[i];
499
500 if (i + 1 == num_periods)
501 ccw->next = mxs_chan->ccw_phys;
502 else
503 ccw->next = mxs_chan->ccw_phys + sizeof(*ccw) * (i + 1);
504
505 ccw->bufaddr = dma_addr;
506 ccw->xfer_bytes = period_len;
507
508 ccw->bits = 0;
509 ccw->bits |= CCW_CHAIN;
510 ccw->bits |= CCW_IRQ;
511 ccw->bits |= CCW_HALT_ON_TERM;
512 ccw->bits |= CCW_TERM_FLUSH;
513 ccw->bits |= BF_CCW(direction == DMA_FROM_DEVICE ?
514 MXS_DMA_CMD_WRITE : MXS_DMA_CMD_READ, COMMAND);
515
516 dma_addr += period_len;
517 buf += period_len;
518
519 i++;
520 }
521
522 return &mxs_chan->desc;
523
524err_out:
525 mxs_chan->status = DMA_ERROR;
526 return NULL;
527}
528
529static int mxs_dma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
530 unsigned long arg)
531{
532 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
533 int ret = 0;
534
535 switch (cmd) {
536 case DMA_TERMINATE_ALL:
537 mxs_dma_disable_chan(mxs_chan);
538 break;
539 case DMA_PAUSE:
540 mxs_dma_pause_chan(mxs_chan);
541 break;
542 case DMA_RESUME:
543 mxs_dma_resume_chan(mxs_chan);
544 break;
545 default:
546 ret = -ENOSYS;
547 }
548
549 return ret;
550}
551
552static enum dma_status mxs_dma_tx_status(struct dma_chan *chan,
553 dma_cookie_t cookie, struct dma_tx_state *txstate)
554{
555 struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
556 dma_cookie_t last_used;
557
558 last_used = chan->cookie;
559 dma_set_tx_state(txstate, mxs_chan->last_completed, last_used, 0);
560
561 return mxs_chan->status;
562}
563
564static void mxs_dma_issue_pending(struct dma_chan *chan)
565{
566 /*
567 * Nothing to do. We only have a single descriptor.
568 */
569}
570
571static int __init mxs_dma_init(struct mxs_dma_engine *mxs_dma)
572{
573 int ret;
574
575 ret = clk_enable(mxs_dma->clk);
576 if (ret)
577 goto err_out;
578
579 ret = mxs_reset_block(mxs_dma->base);
580 if (ret)
581 goto err_out;
582
583 /* only major version matters */
584 mxs_dma->version = readl(mxs_dma->base +
585 ((mxs_dma->dev_id == MXS_DMA_APBX) ?
586 HW_APBX_VERSION : HW_APBH_VERSION)) >>
587 BP_APBHX_VERSION_MAJOR;
588
589 /* enable apbh burst */
590 if (dma_is_apbh()) {
591 writel(BM_APBH_CTRL0_APB_BURST_EN,
592 mxs_dma->base + HW_APBHX_CTRL0 + MXS_SET_ADDR);
593 writel(BM_APBH_CTRL0_APB_BURST8_EN,
594 mxs_dma->base + HW_APBHX_CTRL0 + MXS_SET_ADDR);
595 }
596
597 /* enable irq for all the channels */
598 writel(MXS_DMA_CHANNELS_MASK << MXS_DMA_CHANNELS,
599 mxs_dma->base + HW_APBHX_CTRL1 + MXS_SET_ADDR);
600
601 clk_disable(mxs_dma->clk);
602
603 return 0;
604
605err_out:
606 return ret;
607}
608
609static int __init mxs_dma_probe(struct platform_device *pdev)
610{
611 const struct platform_device_id *id_entry =
612 platform_get_device_id(pdev);
613 struct mxs_dma_engine *mxs_dma;
614 struct resource *iores;
615 int ret, i;
616
617 mxs_dma = kzalloc(sizeof(*mxs_dma), GFP_KERNEL);
618 if (!mxs_dma)
619 return -ENOMEM;
620
621 mxs_dma->dev_id = id_entry->driver_data;
622
623 iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
624
625 if (!request_mem_region(iores->start, resource_size(iores),
626 pdev->name)) {
627 ret = -EBUSY;
628 goto err_request_region;
629 }
630
631 mxs_dma->base = ioremap(iores->start, resource_size(iores));
632 if (!mxs_dma->base) {
633 ret = -ENOMEM;
634 goto err_ioremap;
635 }
636
637 mxs_dma->clk = clk_get(&pdev->dev, NULL);
638 if (IS_ERR(mxs_dma->clk)) {
639 ret = PTR_ERR(mxs_dma->clk);
640 goto err_clk;
641 }
642
643 dma_cap_set(DMA_SLAVE, mxs_dma->dma_device.cap_mask);
644 dma_cap_set(DMA_CYCLIC, mxs_dma->dma_device.cap_mask);
645
646 INIT_LIST_HEAD(&mxs_dma->dma_device.channels);
647
648 /* Initialize channel parameters */
649 for (i = 0; i < MXS_DMA_CHANNELS; i++) {
650 struct mxs_dma_chan *mxs_chan = &mxs_dma->mxs_chans[i];
651
652 mxs_chan->mxs_dma = mxs_dma;
653 mxs_chan->chan.device = &mxs_dma->dma_device;
654
655 tasklet_init(&mxs_chan->tasklet, mxs_dma_tasklet,
656 (unsigned long) mxs_chan);
657
658
659 /* Add the channel to mxs_chan list */
660 list_add_tail(&mxs_chan->chan.device_node,
661 &mxs_dma->dma_device.channels);
662 }
663
664 ret = mxs_dma_init(mxs_dma);
665 if (ret)
666 goto err_init;
667
668 mxs_dma->dma_device.dev = &pdev->dev;
669
670 /* mxs_dma gets 65535 bytes maximum sg size */
671 mxs_dma->dma_device.dev->dma_parms = &mxs_dma->dma_parms;
672 dma_set_max_seg_size(mxs_dma->dma_device.dev, MAX_XFER_BYTES);
673
674 mxs_dma->dma_device.device_alloc_chan_resources = mxs_dma_alloc_chan_resources;
675 mxs_dma->dma_device.device_free_chan_resources = mxs_dma_free_chan_resources;
676 mxs_dma->dma_device.device_tx_status = mxs_dma_tx_status;
677 mxs_dma->dma_device.device_prep_slave_sg = mxs_dma_prep_slave_sg;
678 mxs_dma->dma_device.device_prep_dma_cyclic = mxs_dma_prep_dma_cyclic;
679 mxs_dma->dma_device.device_control = mxs_dma_control;
680 mxs_dma->dma_device.device_issue_pending = mxs_dma_issue_pending;
681
682 ret = dma_async_device_register(&mxs_dma->dma_device);
683 if (ret) {
684 dev_err(mxs_dma->dma_device.dev, "unable to register\n");
685 goto err_init;
686 }
687
688 dev_info(mxs_dma->dma_device.dev, "initialized\n");
689
690 return 0;
691
692err_init:
693 clk_put(mxs_dma->clk);
694err_clk:
695 iounmap(mxs_dma->base);
696err_ioremap:
697 release_mem_region(iores->start, resource_size(iores));
698err_request_region:
699 kfree(mxs_dma);
700 return ret;
701}
702
703static struct platform_device_id mxs_dma_type[] = {
704 {
705 .name = "mxs-dma-apbh",
706 .driver_data = MXS_DMA_APBH,
707 }, {
708 .name = "mxs-dma-apbx",
709 .driver_data = MXS_DMA_APBX,
710 }
711};
712
713static struct platform_driver mxs_dma_driver = {
714 .driver = {
715 .name = "mxs-dma",
716 },
717 .id_table = mxs_dma_type,
718};
719
720static int __init mxs_dma_module_init(void)
721{
722 return platform_driver_probe(&mxs_dma_driver, mxs_dma_probe);
723}
724subsys_initcall(mxs_dma_module_init);
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-18 20:07:37 -0500