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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/pagemap.h>
19#include <linux/scatterlist.h>
20
21#include "tmio_mmc.h"
22
23#define TMIO_MMC_MIN_DMA_LEN 8
24
25void tmio_mmc_enable_dma(struct tmio_mmc_host *host, bool enable)
26{
27 if (!host->chan_tx || !host->chan_rx)
28 return;
29
30 if (host->dma->enable)
31 host->dma->enable(host, enable);
32}
33
34void tmio_mmc_abort_dma(struct tmio_mmc_host *host)
35{
36 tmio_mmc_enable_dma(host, false);
37
38 if (host->chan_rx)
39 dmaengine_terminate_all(host->chan_rx);
40 if (host->chan_tx)
41 dmaengine_terminate_all(host->chan_tx);
42
43 tmio_mmc_enable_dma(host, true);
44}
45
46static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
47{
48 struct scatterlist *sg = host->sg_ptr, *sg_tmp;
49 struct dma_async_tx_descriptor *desc = NULL;
50 struct dma_chan *chan = host->chan_rx;
51 dma_cookie_t cookie;
52 int ret, i;
53 bool aligned = true, multiple = true;
54 unsigned int align = (1 << host->pdata->alignment_shift) - 1;
55
56 for_each_sg(sg, sg_tmp, host->sg_len, i) {
57 if (sg_tmp->offset & align)
58 aligned = false;
59 if (sg_tmp->length & align) {
60 multiple = false;
61 break;
62 }
63 }
64
65 if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_SIZE ||
66 (align & PAGE_MASK))) || !multiple) {
67 ret = -EINVAL;
68 goto pio;
69 }
70
71 if (sg->length < TMIO_MMC_MIN_DMA_LEN) {
72 host->force_pio = true;
73 return;
74 }
75
76 tmio_mmc_disable_mmc_irqs(host, TMIO_STAT_RXRDY);
77
78
79 if (!aligned) {
80 sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
81 host->sg_ptr = &host->bounce_sg;
82 sg = host->sg_ptr;
83 }
84
85 ret = dma_map_sg(chan->device->dev, sg, host->sg_len, DMA_FROM_DEVICE);
86 if (ret > 0)
87 desc = dmaengine_prep_slave_sg(chan, sg, ret,
88 DMA_DEV_TO_MEM, DMA_CTRL_ACK);
89
90 if (desc) {
91 cookie = dmaengine_submit(desc);
92 if (cookie < 0) {
93 desc = NULL;
94 ret = cookie;
95 }
96 }
97pio:
98 if (!desc) {
99
100 tmio_mmc_enable_dma(host, false);
101 if (ret >= 0)
102 ret = -EIO;
103 host->chan_rx = NULL;
104 dma_release_channel(chan);
105
106 chan = host->chan_tx;
107 if (chan) {
108 host->chan_tx = NULL;
109 dma_release_channel(chan);
110 }
111 dev_warn(&host->pdev->dev,
112 "DMA failed: %d, falling back to PIO\n", ret);
113 }
114}
115
116static void tmio_mmc_start_dma_tx(struct tmio_mmc_host *host)
117{
118 struct scatterlist *sg = host->sg_ptr, *sg_tmp;
119 struct dma_async_tx_descriptor *desc = NULL;
120 struct dma_chan *chan = host->chan_tx;
121 dma_cookie_t cookie;
122 int ret, i;
123 bool aligned = true, multiple = true;
124 unsigned int align = (1 << host->pdata->alignment_shift) - 1;
125
126 for_each_sg(sg, sg_tmp, host->sg_len, i) {
127 if (sg_tmp->offset & align)
128 aligned = false;
129 if (sg_tmp->length & align) {
130 multiple = false;
131 break;
132 }
133 }
134
135 if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_SIZE ||
136 (align & PAGE_MASK))) || !multiple) {
137 ret = -EINVAL;
138 goto pio;
139 }
140
141 if (sg->length < TMIO_MMC_MIN_DMA_LEN) {
142 host->force_pio = true;
143 return;
144 }
145
146 tmio_mmc_disable_mmc_irqs(host, TMIO_STAT_TXRQ);
147
148
149 if (!aligned) {
150 unsigned long flags;
151 void *sg_vaddr = tmio_mmc_kmap_atomic(sg, &flags);
152 sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
153 memcpy(host->bounce_buf, sg_vaddr, host->bounce_sg.length);
154 tmio_mmc_kunmap_atomic(sg, &flags, sg_vaddr);
155 host->sg_ptr = &host->bounce_sg;
156 sg = host->sg_ptr;
157 }
158
159 ret = dma_map_sg(chan->device->dev, sg, host->sg_len, DMA_TO_DEVICE);
160 if (ret > 0)
161 desc = dmaengine_prep_slave_sg(chan, sg, ret,
162 DMA_MEM_TO_DEV, DMA_CTRL_ACK);
163
164 if (desc) {
165 cookie = dmaengine_submit(desc);
166 if (cookie < 0) {
167 desc = NULL;
168 ret = cookie;
169 }
170 }
171pio:
172 if (!desc) {
173
174 tmio_mmc_enable_dma(host, false);
175 if (ret >= 0)
176 ret = -EIO;
177 host->chan_tx = NULL;
178 dma_release_channel(chan);
179
180 chan = host->chan_rx;
181 if (chan) {
182 host->chan_rx = NULL;
183 dma_release_channel(chan);
184 }
185 dev_warn(&host->pdev->dev,
186 "DMA failed: %d, falling back to PIO\n", ret);
187 }
188}
189
190void tmio_mmc_start_dma(struct tmio_mmc_host *host,
191 struct mmc_data *data)
192{
193 if (data->flags & MMC_DATA_READ) {
194 if (host->chan_rx)
195 tmio_mmc_start_dma_rx(host);
196 } else {
197 if (host->chan_tx)
198 tmio_mmc_start_dma_tx(host);
199 }
200}
201
202static void tmio_mmc_issue_tasklet_fn(unsigned long priv)
203{
204 struct tmio_mmc_host *host = (struct tmio_mmc_host *)priv;
205 struct dma_chan *chan = NULL;
206
207 spin_lock_irq(&host->lock);
208
209 if (host && host->data) {
210 if (host->data->flags & MMC_DATA_READ)
211 chan = host->chan_rx;
212 else
213 chan = host->chan_tx;
214 }
215
216 spin_unlock_irq(&host->lock);
217
218 tmio_mmc_enable_mmc_irqs(host, TMIO_STAT_DATAEND);
219
220 if (chan)
221 dma_async_issue_pending(chan);
222}
223
224static void tmio_mmc_tasklet_fn(unsigned long arg)
225{
226 struct tmio_mmc_host *host = (struct tmio_mmc_host *)arg;
227
228 spin_lock_irq(&host->lock);
229
230 if (!host->data)
231 goto out;
232
233 if (host->data->flags & MMC_DATA_READ)
234 dma_unmap_sg(host->chan_rx->device->dev,
235 host->sg_ptr, host->sg_len,
236 DMA_FROM_DEVICE);
237 else
238 dma_unmap_sg(host->chan_tx->device->dev,
239 host->sg_ptr, host->sg_len,
240 DMA_TO_DEVICE);
241
242 tmio_mmc_do_data_irq(host);
243out:
244 spin_unlock_irq(&host->lock);
245}
246
247void tmio_mmc_request_dma(struct tmio_mmc_host *host, struct tmio_mmc_data *pdata)
248{
249
250 if (!host->dma || (!host->pdev->dev.of_node &&
251 (!pdata->chan_priv_tx || !pdata->chan_priv_rx)))
252 return;
253
254 if (!host->chan_tx && !host->chan_rx) {
255 struct resource *res = platform_get_resource(host->pdev,
256 IORESOURCE_MEM, 0);
257 struct dma_slave_config cfg = {};
258 dma_cap_mask_t mask;
259 int ret;
260
261 if (!res)
262 return;
263
264 dma_cap_zero(mask);
265 dma_cap_set(DMA_SLAVE, mask);
266
267 host->chan_tx = dma_request_slave_channel_compat(mask,
268 host->dma->filter, pdata->chan_priv_tx,
269 &host->pdev->dev, "tx");
270 dev_dbg(&host->pdev->dev, "%s: TX: got channel %p\n", __func__,
271 host->chan_tx);
272
273 if (!host->chan_tx)
274 return;
275
276 cfg.direction = DMA_MEM_TO_DEV;
277 cfg.dst_addr = res->start + (CTL_SD_DATA_PORT << host->bus_shift);
278 cfg.dst_addr_width = host->dma->dma_buswidth;
279 if (!cfg.dst_addr_width)
280 cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
281 cfg.src_addr = 0;
282 ret = dmaengine_slave_config(host->chan_tx, &cfg);
283 if (ret < 0)
284 goto ecfgtx;
285
286 host->chan_rx = dma_request_slave_channel_compat(mask,
287 host->dma->filter, pdata->chan_priv_rx,
288 &host->pdev->dev, "rx");
289 dev_dbg(&host->pdev->dev, "%s: RX: got channel %p\n", __func__,
290 host->chan_rx);
291
292 if (!host->chan_rx)
293 goto ereqrx;
294
295 cfg.direction = DMA_DEV_TO_MEM;
296 cfg.src_addr = cfg.dst_addr + host->pdata->dma_rx_offset;
297 cfg.src_addr_width = host->dma->dma_buswidth;
298 if (!cfg.src_addr_width)
299 cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
300 cfg.dst_addr = 0;
301 ret = dmaengine_slave_config(host->chan_rx, &cfg);
302 if (ret < 0)
303 goto ecfgrx;
304
305 host->bounce_buf = (u8 *)__get_free_page(GFP_KERNEL | GFP_DMA);
306 if (!host->bounce_buf)
307 goto ebouncebuf;
308
309 tasklet_init(&host->dma_complete, tmio_mmc_tasklet_fn, (unsigned long)host);
310 tasklet_init(&host->dma_issue, tmio_mmc_issue_tasklet_fn, (unsigned long)host);
311 }
312
313 tmio_mmc_enable_dma(host, true);
314
315 return;
316
317ebouncebuf:
318ecfgrx:
319 dma_release_channel(host->chan_rx);
320 host->chan_rx = NULL;
321ereqrx:
322ecfgtx:
323 dma_release_channel(host->chan_tx);
324 host->chan_tx = NULL;
325}
326
327void tmio_mmc_release_dma(struct tmio_mmc_host *host)
328{
329 if (host->chan_tx) {
330 struct dma_chan *chan = host->chan_tx;
331 host->chan_tx = NULL;
332 dma_release_channel(chan);
333 }
334 if (host->chan_rx) {
335 struct dma_chan *chan = host->chan_rx;
336 host->chan_rx = NULL;
337 dma_release_channel(chan);
338 }
339 if (host->bounce_buf) {
340 free_pages((unsigned long)host->bounce_buf, 0);
341 host->bounce_buf = NULL;
342 }
343}
344
