Loading...
1/*
2 * linux/drivers/mmc/tmio_mmc_dma.c
3 *
4 * Copyright (C) 2010-2011 Guennadi Liakhovetski
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 * DMA function for TMIO MMC implementations
11 */
12
13#include <linux/device.h>
14#include <linux/dma-mapping.h>
15#include <linux/dmaengine.h>
16#include <linux/mfd/tmio.h>
17#include <linux/mmc/host.h>
18#include <linux/mmc/tmio.h>
19#include <linux/pagemap.h>
20#include <linux/scatterlist.h>
21
22#include "tmio_mmc.h"
23
24#define TMIO_MMC_MIN_DMA_LEN 8
25
26void tmio_mmc_enable_dma(struct tmio_mmc_host *host, bool enable)
27{
28 if (!host->chan_tx || !host->chan_rx)
29 return;
30
31 if (host->dma->enable)
32 host->dma->enable(host, enable);
33}
34
35void tmio_mmc_abort_dma(struct tmio_mmc_host *host)
36{
37 tmio_mmc_enable_dma(host, false);
38
39 if (host->chan_rx)
40 dmaengine_terminate_all(host->chan_rx);
41 if (host->chan_tx)
42 dmaengine_terminate_all(host->chan_tx);
43
44 tmio_mmc_enable_dma(host, true);
45}
46
47static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
48{
49 struct scatterlist *sg = host->sg_ptr, *sg_tmp;
50 struct dma_async_tx_descriptor *desc = NULL;
51 struct dma_chan *chan = host->chan_rx;
52 dma_cookie_t cookie;
53 int ret, i;
54 bool aligned = true, multiple = true;
55 unsigned int align = (1 << host->pdata->alignment_shift) - 1;
56
57 for_each_sg(sg, sg_tmp, host->sg_len, i) {
58 if (sg_tmp->offset & align)
59 aligned = false;
60 if (sg_tmp->length & align) {
61 multiple = false;
62 break;
63 }
64 }
65
66 if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_SIZE ||
67 (align & PAGE_MASK))) || !multiple) {
68 ret = -EINVAL;
69 goto pio;
70 }
71
72 if (sg->length < TMIO_MMC_MIN_DMA_LEN) {
73 host->force_pio = true;
74 return;
75 }
76
77 tmio_mmc_disable_mmc_irqs(host, TMIO_STAT_RXRDY);
78
79 /* The only sg element can be unaligned, use our bounce buffer then */
80 if (!aligned) {
81 sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
82 host->sg_ptr = &host->bounce_sg;
83 sg = host->sg_ptr;
84 }
85
86 ret = dma_map_sg(chan->device->dev, sg, host->sg_len, DMA_FROM_DEVICE);
87 if (ret > 0)
88 desc = dmaengine_prep_slave_sg(chan, sg, ret,
89 DMA_DEV_TO_MEM, DMA_CTRL_ACK);
90
91 if (desc) {
92 cookie = dmaengine_submit(desc);
93 if (cookie < 0) {
94 desc = NULL;
95 ret = cookie;
96 }
97 }
98pio:
99 if (!desc) {
100 /* DMA failed, fall back to PIO */
101 tmio_mmc_enable_dma(host, false);
102 if (ret >= 0)
103 ret = -EIO;
104 host->chan_rx = NULL;
105 dma_release_channel(chan);
106 /* Free the Tx channel too */
107 chan = host->chan_tx;
108 if (chan) {
109 host->chan_tx = NULL;
110 dma_release_channel(chan);
111 }
112 dev_warn(&host->pdev->dev,
113 "DMA failed: %d, falling back to PIO\n", ret);
114 }
115}
116
117static void tmio_mmc_start_dma_tx(struct tmio_mmc_host *host)
118{
119 struct scatterlist *sg = host->sg_ptr, *sg_tmp;
120 struct dma_async_tx_descriptor *desc = NULL;
121 struct dma_chan *chan = host->chan_tx;
122 dma_cookie_t cookie;
123 int ret, i;
124 bool aligned = true, multiple = true;
125 unsigned int align = (1 << host->pdata->alignment_shift) - 1;
126
127 for_each_sg(sg, sg_tmp, host->sg_len, i) {
128 if (sg_tmp->offset & align)
129 aligned = false;
130 if (sg_tmp->length & align) {
131 multiple = false;
132 break;
133 }
134 }
135
136 if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_SIZE ||
137 (align & PAGE_MASK))) || !multiple) {
138 ret = -EINVAL;
139 goto pio;
140 }
141
142 if (sg->length < TMIO_MMC_MIN_DMA_LEN) {
143 host->force_pio = true;
144 return;
145 }
146
147 tmio_mmc_disable_mmc_irqs(host, TMIO_STAT_TXRQ);
148
149 /* The only sg element can be unaligned, use our bounce buffer then */
150 if (!aligned) {
151 unsigned long flags;
152 void *sg_vaddr = tmio_mmc_kmap_atomic(sg, &flags);
153 sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
154 memcpy(host->bounce_buf, sg_vaddr, host->bounce_sg.length);
155 tmio_mmc_kunmap_atomic(sg, &flags, sg_vaddr);
156 host->sg_ptr = &host->bounce_sg;
157 sg = host->sg_ptr;
158 }
159
160 ret = dma_map_sg(chan->device->dev, sg, host->sg_len, DMA_TO_DEVICE);
161 if (ret > 0)
162 desc = dmaengine_prep_slave_sg(chan, sg, ret,
163 DMA_MEM_TO_DEV, DMA_CTRL_ACK);
164
165 if (desc) {
166 cookie = dmaengine_submit(desc);
167 if (cookie < 0) {
168 desc = NULL;
169 ret = cookie;
170 }
171 }
172pio:
173 if (!desc) {
174 /* DMA failed, fall back to PIO */
175 tmio_mmc_enable_dma(host, false);
176 if (ret >= 0)
177 ret = -EIO;
178 host->chan_tx = NULL;
179 dma_release_channel(chan);
180 /* Free the Rx channel too */
181 chan = host->chan_rx;
182 if (chan) {
183 host->chan_rx = NULL;
184 dma_release_channel(chan);
185 }
186 dev_warn(&host->pdev->dev,
187 "DMA failed: %d, falling back to PIO\n", ret);
188 }
189}
190
191void tmio_mmc_start_dma(struct tmio_mmc_host *host,
192 struct mmc_data *data)
193{
194 if (data->flags & MMC_DATA_READ) {
195 if (host->chan_rx)
196 tmio_mmc_start_dma_rx(host);
197 } else {
198 if (host->chan_tx)
199 tmio_mmc_start_dma_tx(host);
200 }
201}
202
203static void tmio_mmc_issue_tasklet_fn(unsigned long priv)
204{
205 struct tmio_mmc_host *host = (struct tmio_mmc_host *)priv;
206 struct dma_chan *chan = NULL;
207
208 spin_lock_irq(&host->lock);
209
210 if (host && host->data) {
211 if (host->data->flags & MMC_DATA_READ)
212 chan = host->chan_rx;
213 else
214 chan = host->chan_tx;
215 }
216
217 spin_unlock_irq(&host->lock);
218
219 tmio_mmc_enable_mmc_irqs(host, TMIO_STAT_DATAEND);
220
221 if (chan)
222 dma_async_issue_pending(chan);
223}
224
225static void tmio_mmc_tasklet_fn(unsigned long arg)
226{
227 struct tmio_mmc_host *host = (struct tmio_mmc_host *)arg;
228
229 spin_lock_irq(&host->lock);
230
231 if (!host->data)
232 goto out;
233
234 if (host->data->flags & MMC_DATA_READ)
235 dma_unmap_sg(host->chan_rx->device->dev,
236 host->sg_ptr, host->sg_len,
237 DMA_FROM_DEVICE);
238 else
239 dma_unmap_sg(host->chan_tx->device->dev,
240 host->sg_ptr, host->sg_len,
241 DMA_TO_DEVICE);
242
243 tmio_mmc_do_data_irq(host);
244out:
245 spin_unlock_irq(&host->lock);
246}
247
248void tmio_mmc_request_dma(struct tmio_mmc_host *host, struct tmio_mmc_data *pdata)
249{
250 /* We can only either use DMA for both Tx and Rx or not use it at all */
251 if (!host->dma || (!host->pdev->dev.of_node &&
252 (!pdata->chan_priv_tx || !pdata->chan_priv_rx)))
253 return;
254
255 if (!host->chan_tx && !host->chan_rx) {
256 struct resource *res = platform_get_resource(host->pdev,
257 IORESOURCE_MEM, 0);
258 struct dma_slave_config cfg = {};
259 dma_cap_mask_t mask;
260 int ret;
261
262 if (!res)
263 return;
264
265 dma_cap_zero(mask);
266 dma_cap_set(DMA_SLAVE, mask);
267
268 host->chan_tx = dma_request_slave_channel_compat(mask,
269 host->dma->filter, pdata->chan_priv_tx,
270 &host->pdev->dev, "tx");
271 dev_dbg(&host->pdev->dev, "%s: TX: got channel %p\n", __func__,
272 host->chan_tx);
273
274 if (!host->chan_tx)
275 return;
276
277 cfg.direction = DMA_MEM_TO_DEV;
278 cfg.dst_addr = res->start + (CTL_SD_DATA_PORT << host->bus_shift);
279 cfg.dst_addr_width = host->dma->dma_buswidth;
280 if (!cfg.dst_addr_width)
281 cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
282 cfg.src_addr = 0;
283 ret = dmaengine_slave_config(host->chan_tx, &cfg);
284 if (ret < 0)
285 goto ecfgtx;
286
287 host->chan_rx = dma_request_slave_channel_compat(mask,
288 host->dma->filter, pdata->chan_priv_rx,
289 &host->pdev->dev, "rx");
290 dev_dbg(&host->pdev->dev, "%s: RX: got channel %p\n", __func__,
291 host->chan_rx);
292
293 if (!host->chan_rx)
294 goto ereqrx;
295
296 cfg.direction = DMA_DEV_TO_MEM;
297 cfg.src_addr = cfg.dst_addr + host->pdata->dma_rx_offset;
298 cfg.src_addr_width = host->dma->dma_buswidth;
299 if (!cfg.src_addr_width)
300 cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
301 cfg.dst_addr = 0;
302 ret = dmaengine_slave_config(host->chan_rx, &cfg);
303 if (ret < 0)
304 goto ecfgrx;
305
306 host->bounce_buf = (u8 *)__get_free_page(GFP_KERNEL | GFP_DMA);
307 if (!host->bounce_buf)
308 goto ebouncebuf;
309
310 tasklet_init(&host->dma_complete, tmio_mmc_tasklet_fn, (unsigned long)host);
311 tasklet_init(&host->dma_issue, tmio_mmc_issue_tasklet_fn, (unsigned long)host);
312 }
313
314 tmio_mmc_enable_dma(host, true);
315
316 return;
317
318ebouncebuf:
319ecfgrx:
320 dma_release_channel(host->chan_rx);
321 host->chan_rx = NULL;
322ereqrx:
323ecfgtx:
324 dma_release_channel(host->chan_tx);
325 host->chan_tx = NULL;
326}
327
328void tmio_mmc_release_dma(struct tmio_mmc_host *host)
329{
330 if (host->chan_tx) {
331 struct dma_chan *chan = host->chan_tx;
332 host->chan_tx = NULL;
333 dma_release_channel(chan);
334 }
335 if (host->chan_rx) {
336 struct dma_chan *chan = host->chan_rx;
337 host->chan_rx = NULL;
338 dma_release_channel(chan);
339 }
340 if (host->bounce_buf) {
341 free_pages((unsigned long)host->bounce_buf, 0);
342 host->bounce_buf = NULL;
343 }
344}
1/*
2 * linux/drivers/mmc/tmio_mmc_dma.c
3 *
4 * Copyright (C) 2010-2011 Guennadi Liakhovetski
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 * DMA function for TMIO MMC implementations
11 */
12
13#include <linux/device.h>
14#include <linux/dma-mapping.h>
15#include <linux/dmaengine.h>
16#include <linux/mfd/tmio.h>
17#include <linux/mmc/host.h>
18#include <linux/mmc/tmio.h>
19#include <linux/pagemap.h>
20#include <linux/scatterlist.h>
21
22#include "tmio_mmc.h"
23
24#define TMIO_MMC_MIN_DMA_LEN 8
25
26void tmio_mmc_enable_dma(struct tmio_mmc_host *host, bool enable)
27{
28 if (!host->chan_tx || !host->chan_rx)
29 return;
30
31#if defined(CONFIG_SUPERH) || defined(CONFIG_ARCH_SHMOBILE)
32 /* Switch DMA mode on or off - SuperH specific? */
33 sd_ctrl_write16(host, CTL_DMA_ENABLE, enable ? 2 : 0);
34#endif
35}
36
37void tmio_mmc_abort_dma(struct tmio_mmc_host *host)
38{
39 tmio_mmc_enable_dma(host, false);
40
41 if (host->chan_rx)
42 dmaengine_terminate_all(host->chan_rx);
43 if (host->chan_tx)
44 dmaengine_terminate_all(host->chan_tx);
45
46 tmio_mmc_enable_dma(host, true);
47}
48
49static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
50{
51 struct scatterlist *sg = host->sg_ptr, *sg_tmp;
52 struct dma_async_tx_descriptor *desc = NULL;
53 struct dma_chan *chan = host->chan_rx;
54 struct tmio_mmc_data *pdata = host->pdata;
55 dma_cookie_t cookie;
56 int ret, i;
57 bool aligned = true, multiple = true;
58 unsigned int align = (1 << pdata->dma->alignment_shift) - 1;
59
60 for_each_sg(sg, sg_tmp, host->sg_len, i) {
61 if (sg_tmp->offset & align)
62 aligned = false;
63 if (sg_tmp->length & align) {
64 multiple = false;
65 break;
66 }
67 }
68
69 if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_CACHE_SIZE ||
70 (align & PAGE_MASK))) || !multiple) {
71 ret = -EINVAL;
72 goto pio;
73 }
74
75 if (sg->length < TMIO_MMC_MIN_DMA_LEN) {
76 host->force_pio = true;
77 return;
78 }
79
80 tmio_mmc_disable_mmc_irqs(host, TMIO_STAT_RXRDY);
81
82 /* The only sg element can be unaligned, use our bounce buffer then */
83 if (!aligned) {
84 sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
85 host->sg_ptr = &host->bounce_sg;
86 sg = host->sg_ptr;
87 }
88
89 ret = dma_map_sg(chan->device->dev, sg, host->sg_len, DMA_FROM_DEVICE);
90 if (ret > 0)
91 desc = dmaengine_prep_slave_sg(chan, sg, ret,
92 DMA_DEV_TO_MEM, DMA_CTRL_ACK);
93
94 if (desc) {
95 cookie = dmaengine_submit(desc);
96 if (cookie < 0) {
97 desc = NULL;
98 ret = cookie;
99 }
100 }
101 dev_dbg(&host->pdev->dev, "%s(): mapped %d -> %d, cookie %d, rq %p\n",
102 __func__, host->sg_len, ret, cookie, host->mrq);
103
104pio:
105 if (!desc) {
106 /* DMA failed, fall back to PIO */
107 if (ret >= 0)
108 ret = -EIO;
109 host->chan_rx = NULL;
110 dma_release_channel(chan);
111 /* Free the Tx channel too */
112 chan = host->chan_tx;
113 if (chan) {
114 host->chan_tx = NULL;
115 dma_release_channel(chan);
116 }
117 dev_warn(&host->pdev->dev,
118 "DMA failed: %d, falling back to PIO\n", ret);
119 tmio_mmc_enable_dma(host, false);
120 }
121
122 dev_dbg(&host->pdev->dev, "%s(): desc %p, cookie %d, sg[%d]\n", __func__,
123 desc, cookie, host->sg_len);
124}
125
126static void tmio_mmc_start_dma_tx(struct tmio_mmc_host *host)
127{
128 struct scatterlist *sg = host->sg_ptr, *sg_tmp;
129 struct dma_async_tx_descriptor *desc = NULL;
130 struct dma_chan *chan = host->chan_tx;
131 struct tmio_mmc_data *pdata = host->pdata;
132 dma_cookie_t cookie;
133 int ret, i;
134 bool aligned = true, multiple = true;
135 unsigned int align = (1 << pdata->dma->alignment_shift) - 1;
136
137 for_each_sg(sg, sg_tmp, host->sg_len, i) {
138 if (sg_tmp->offset & align)
139 aligned = false;
140 if (sg_tmp->length & align) {
141 multiple = false;
142 break;
143 }
144 }
145
146 if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_CACHE_SIZE ||
147 (align & PAGE_MASK))) || !multiple) {
148 ret = -EINVAL;
149 goto pio;
150 }
151
152 if (sg->length < TMIO_MMC_MIN_DMA_LEN) {
153 host->force_pio = true;
154 return;
155 }
156
157 tmio_mmc_disable_mmc_irqs(host, TMIO_STAT_TXRQ);
158
159 /* The only sg element can be unaligned, use our bounce buffer then */
160 if (!aligned) {
161 unsigned long flags;
162 void *sg_vaddr = tmio_mmc_kmap_atomic(sg, &flags);
163 sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
164 memcpy(host->bounce_buf, sg_vaddr, host->bounce_sg.length);
165 tmio_mmc_kunmap_atomic(sg, &flags, sg_vaddr);
166 host->sg_ptr = &host->bounce_sg;
167 sg = host->sg_ptr;
168 }
169
170 ret = dma_map_sg(chan->device->dev, sg, host->sg_len, DMA_TO_DEVICE);
171 if (ret > 0)
172 desc = dmaengine_prep_slave_sg(chan, sg, ret,
173 DMA_MEM_TO_DEV, DMA_CTRL_ACK);
174
175 if (desc) {
176 cookie = dmaengine_submit(desc);
177 if (cookie < 0) {
178 desc = NULL;
179 ret = cookie;
180 }
181 }
182 dev_dbg(&host->pdev->dev, "%s(): mapped %d -> %d, cookie %d, rq %p\n",
183 __func__, host->sg_len, ret, cookie, host->mrq);
184
185pio:
186 if (!desc) {
187 /* DMA failed, fall back to PIO */
188 if (ret >= 0)
189 ret = -EIO;
190 host->chan_tx = NULL;
191 dma_release_channel(chan);
192 /* Free the Rx channel too */
193 chan = host->chan_rx;
194 if (chan) {
195 host->chan_rx = NULL;
196 dma_release_channel(chan);
197 }
198 dev_warn(&host->pdev->dev,
199 "DMA failed: %d, falling back to PIO\n", ret);
200 tmio_mmc_enable_dma(host, false);
201 }
202
203 dev_dbg(&host->pdev->dev, "%s(): desc %p, cookie %d\n", __func__,
204 desc, cookie);
205}
206
207void tmio_mmc_start_dma(struct tmio_mmc_host *host,
208 struct mmc_data *data)
209{
210 if (data->flags & MMC_DATA_READ) {
211 if (host->chan_rx)
212 tmio_mmc_start_dma_rx(host);
213 } else {
214 if (host->chan_tx)
215 tmio_mmc_start_dma_tx(host);
216 }
217}
218
219static void tmio_mmc_issue_tasklet_fn(unsigned long priv)
220{
221 struct tmio_mmc_host *host = (struct tmio_mmc_host *)priv;
222 struct dma_chan *chan = NULL;
223
224 spin_lock_irq(&host->lock);
225
226 if (host && host->data) {
227 if (host->data->flags & MMC_DATA_READ)
228 chan = host->chan_rx;
229 else
230 chan = host->chan_tx;
231 }
232
233 spin_unlock_irq(&host->lock);
234
235 tmio_mmc_enable_mmc_irqs(host, TMIO_STAT_DATAEND);
236
237 if (chan)
238 dma_async_issue_pending(chan);
239}
240
241static void tmio_mmc_tasklet_fn(unsigned long arg)
242{
243 struct tmio_mmc_host *host = (struct tmio_mmc_host *)arg;
244
245 spin_lock_irq(&host->lock);
246
247 if (!host->data)
248 goto out;
249
250 if (host->data->flags & MMC_DATA_READ)
251 dma_unmap_sg(host->chan_rx->device->dev,
252 host->sg_ptr, host->sg_len,
253 DMA_FROM_DEVICE);
254 else
255 dma_unmap_sg(host->chan_tx->device->dev,
256 host->sg_ptr, host->sg_len,
257 DMA_TO_DEVICE);
258
259 tmio_mmc_do_data_irq(host);
260out:
261 spin_unlock_irq(&host->lock);
262}
263
264/* It might be necessary to make filter MFD specific */
265static bool tmio_mmc_filter(struct dma_chan *chan, void *arg)
266{
267 dev_dbg(chan->device->dev, "%s: slave data %p\n", __func__, arg);
268 chan->private = arg;
269 return true;
270}
271
272void tmio_mmc_request_dma(struct tmio_mmc_host *host, struct tmio_mmc_data *pdata)
273{
274 /* We can only either use DMA for both Tx and Rx or not use it at all */
275 if (!pdata->dma)
276 return;
277
278 if (!host->chan_tx && !host->chan_rx) {
279 dma_cap_mask_t mask;
280
281 dma_cap_zero(mask);
282 dma_cap_set(DMA_SLAVE, mask);
283
284 host->chan_tx = dma_request_channel(mask, tmio_mmc_filter,
285 pdata->dma->chan_priv_tx);
286 dev_dbg(&host->pdev->dev, "%s: TX: got channel %p\n", __func__,
287 host->chan_tx);
288
289 if (!host->chan_tx)
290 return;
291
292 host->chan_rx = dma_request_channel(mask, tmio_mmc_filter,
293 pdata->dma->chan_priv_rx);
294 dev_dbg(&host->pdev->dev, "%s: RX: got channel %p\n", __func__,
295 host->chan_rx);
296
297 if (!host->chan_rx)
298 goto ereqrx;
299
300 host->bounce_buf = (u8 *)__get_free_page(GFP_KERNEL | GFP_DMA);
301 if (!host->bounce_buf)
302 goto ebouncebuf;
303
304 tasklet_init(&host->dma_complete, tmio_mmc_tasklet_fn, (unsigned long)host);
305 tasklet_init(&host->dma_issue, tmio_mmc_issue_tasklet_fn, (unsigned long)host);
306 }
307
308 tmio_mmc_enable_dma(host, true);
309
310 return;
311
312ebouncebuf:
313 dma_release_channel(host->chan_rx);
314 host->chan_rx = NULL;
315ereqrx:
316 dma_release_channel(host->chan_tx);
317 host->chan_tx = NULL;
318}
319
320void tmio_mmc_release_dma(struct tmio_mmc_host *host)
321{
322 if (host->chan_tx) {
323 struct dma_chan *chan = host->chan_tx;
324 host->chan_tx = NULL;
325 dma_release_channel(chan);
326 }
327 if (host->chan_rx) {
328 struct dma_chan *chan = host->chan_rx;
329 host->chan_rx = NULL;
330 dma_release_channel(chan);
331 }
332 if (host->bounce_buf) {
333 free_pages((unsigned long)host->bounce_buf, 0);
334 host->bounce_buf = NULL;
335 }
336}