1// SPDX-License-Identifier: GPL-2.0
2/*
3 * DMA support use of SYS DMAC with SDHI SD/SDIO controller
4 *
5 * Copyright (C) 2016-19 Renesas Electronics Corporation
6 * Copyright (C) 2016-19 Sang Engineering, Wolfram Sang
7 * Copyright (C) 2017 Horms Solutions, Simon Horman
8 * Copyright (C) 2010-2011 Guennadi Liakhovetski
9 */
10
11#include <linux/device.h>
12#include <linux/dma-mapping.h>
13#include <linux/dmaengine.h>
14#include <linux/mfd/tmio.h>
15#include <linux/mmc/host.h>
16#include <linux/mod_devicetable.h>
17#include <linux/module.h>
18#include <linux/of.h>
19#include <linux/platform_device.h>
20#include <linux/pagemap.h>
21#include <linux/scatterlist.h>
22#include <linux/sys_soc.h>
23
24#include "renesas_sdhi.h"
25#include "tmio_mmc.h"
26
27#define TMIO_MMC_MIN_DMA_LEN 8
28
29static const struct renesas_sdhi_of_data of_default_cfg = {
30 .tmio_flags = TMIO_MMC_HAS_IDLE_WAIT,
31};
32
33static const struct renesas_sdhi_of_data of_rz_compatible = {
34 .tmio_flags = TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_32BIT_DATA_PORT |
35 TMIO_MMC_HAVE_CBSY,
36 .tmio_ocr_mask = MMC_VDD_32_33,
37 .capabilities = MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ |
38 MMC_CAP_WAIT_WHILE_BUSY,
39};
40
41static const struct renesas_sdhi_of_data of_rcar_gen1_compatible = {
42 .tmio_flags = TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_CLK_ACTUAL,
43 .capabilities = MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ |
44 MMC_CAP_WAIT_WHILE_BUSY,
45 .capabilities2 = MMC_CAP2_NO_WRITE_PROTECT,
46};
47
48/* Definitions for sampling clocks */
49static struct renesas_sdhi_scc rcar_gen2_scc_taps[] = {
50 {
51 .clk_rate = 156000000,
52 .tap = 0x00000703,
53 },
54 {
55 .clk_rate = 0,
56 .tap = 0x00000300,
57 },
58};
59
60static const struct renesas_sdhi_of_data of_rcar_gen2_compatible = {
61 .tmio_flags = TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_CLK_ACTUAL |
62 TMIO_MMC_HAVE_CBSY | TMIO_MMC_MIN_RCAR2,
63 .capabilities = MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ |
64 MMC_CAP_CMD23 | MMC_CAP_WAIT_WHILE_BUSY,
65 .capabilities2 = MMC_CAP2_NO_WRITE_PROTECT,
66 .dma_buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES,
67 .dma_rx_offset = 0x2000,
68 .scc_offset = 0x0300,
69 .taps = rcar_gen2_scc_taps,
70 .taps_num = ARRAY_SIZE(rcar_gen2_scc_taps),
71 .max_blk_count = UINT_MAX / TMIO_MAX_BLK_SIZE,
72};
73
74static const struct of_device_id renesas_sdhi_sys_dmac_of_match[] = {
75 { .compatible = "renesas,sdhi-sh73a0", .data = &of_default_cfg, },
76 { .compatible = "renesas,sdhi-r8a73a4", .data = &of_default_cfg, },
77 { .compatible = "renesas,sdhi-r8a7740", .data = &of_default_cfg, },
78 { .compatible = "renesas,sdhi-r7s72100", .data = &of_rz_compatible, },
79 { .compatible = "renesas,sdhi-r8a7778", .data = &of_rcar_gen1_compatible, },
80 { .compatible = "renesas,sdhi-r8a7779", .data = &of_rcar_gen1_compatible, },
81 { .compatible = "renesas,sdhi-r8a7743", .data = &of_rcar_gen2_compatible, },
82 { .compatible = "renesas,sdhi-r8a7745", .data = &of_rcar_gen2_compatible, },
83 { .compatible = "renesas,sdhi-r8a7790", .data = &of_rcar_gen2_compatible, },
84 { .compatible = "renesas,sdhi-r8a7791", .data = &of_rcar_gen2_compatible, },
85 { .compatible = "renesas,sdhi-r8a7792", .data = &of_rcar_gen2_compatible, },
86 { .compatible = "renesas,sdhi-r8a7793", .data = &of_rcar_gen2_compatible, },
87 { .compatible = "renesas,sdhi-r8a7794", .data = &of_rcar_gen2_compatible, },
88 { .compatible = "renesas,rcar-gen1-sdhi", .data = &of_rcar_gen1_compatible, },
89 { .compatible = "renesas,rcar-gen2-sdhi", .data = &of_rcar_gen2_compatible, },
90 { .compatible = "renesas,sdhi-shmobile" },
91 {},
92};
93MODULE_DEVICE_TABLE(of, renesas_sdhi_sys_dmac_of_match);
94
95static void renesas_sdhi_sys_dmac_enable_dma(struct tmio_mmc_host *host,
96 bool enable)
97{
98 struct renesas_sdhi *priv = host_to_priv(host);
99
100 if (!host->chan_tx || !host->chan_rx)
101 return;
102
103 if (priv->dma_priv.enable)
104 priv->dma_priv.enable(host, enable);
105}
106
107static void renesas_sdhi_sys_dmac_abort_dma(struct tmio_mmc_host *host)
108{
109 renesas_sdhi_sys_dmac_enable_dma(host, enable: false);
110
111 if (host->chan_rx)
112 dmaengine_terminate_sync(chan: host->chan_rx);
113 if (host->chan_tx)
114 dmaengine_terminate_sync(chan: host->chan_tx);
115
116 renesas_sdhi_sys_dmac_enable_dma(host, enable: true);
117}
118
119static void renesas_sdhi_sys_dmac_dataend_dma(struct tmio_mmc_host *host)
120{
121 struct renesas_sdhi *priv = host_to_priv(host);
122
123 complete(&priv->dma_priv.dma_dataend);
124}
125
126static void renesas_sdhi_sys_dmac_dma_callback(void *arg)
127{
128 struct tmio_mmc_host *host = arg;
129 struct renesas_sdhi *priv = host_to_priv(host);
130
131 spin_lock_irq(lock: &host->lock);
132
133 if (!host->data)
134 goto out;
135
136 if (host->data->flags & MMC_DATA_READ)
137 dma_unmap_sg(host->chan_rx->device->dev,
138 host->sg_ptr, host->sg_len,
139 DMA_FROM_DEVICE);
140 else
141 dma_unmap_sg(host->chan_tx->device->dev,
142 host->sg_ptr, host->sg_len,
143 DMA_TO_DEVICE);
144
145 spin_unlock_irq(lock: &host->lock);
146
147 wait_for_completion(&priv->dma_priv.dma_dataend);
148
149 spin_lock_irq(lock: &host->lock);
150 tmio_mmc_do_data_irq(host);
151out:
152 spin_unlock_irq(lock: &host->lock);
153}
154
155static void renesas_sdhi_sys_dmac_start_dma_rx(struct tmio_mmc_host *host)
156{
157 struct renesas_sdhi *priv = host_to_priv(host);
158 struct scatterlist *sg = host->sg_ptr, *sg_tmp;
159 struct dma_async_tx_descriptor *desc = NULL;
160 struct dma_chan *chan = host->chan_rx;
161 dma_cookie_t cookie;
162 int ret, i;
163 bool aligned = true, multiple = true;
164 unsigned int align = 1; /* 2-byte alignment */
165
166 for_each_sg(sg, sg_tmp, host->sg_len, i) {
167 if (sg_tmp->offset & align)
168 aligned = false;
169 if (sg_tmp->length & align) {
170 multiple = false;
171 break;
172 }
173 }
174
175 if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_SIZE ||
176 (align & PAGE_MASK))) || !multiple) {
177 ret = -EINVAL;
178 goto pio;
179 }
180
181 if (sg->length < TMIO_MMC_MIN_DMA_LEN)
182 return;
183
184 /* The only sg element can be unaligned, use our bounce buffer then */
185 if (!aligned) {
186 sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
187 host->sg_ptr = &host->bounce_sg;
188 sg = host->sg_ptr;
189 }
190
191 ret = dma_map_sg(chan->device->dev, sg, host->sg_len, DMA_FROM_DEVICE);
192 if (ret > 0)
193 desc = dmaengine_prep_slave_sg(chan, sgl: sg, sg_len: ret, dir: DMA_DEV_TO_MEM,
194 flags: DMA_CTRL_ACK);
195
196 if (desc) {
197 reinit_completion(x: &priv->dma_priv.dma_dataend);
198 desc->callback = renesas_sdhi_sys_dmac_dma_callback;
199 desc->callback_param = host;
200
201 cookie = dmaengine_submit(desc);
202 if (cookie < 0) {
203 desc = NULL;
204 ret = cookie;
205 }
206 host->dma_on = true;
207 }
208pio:
209 if (!desc) {
210 /* DMA failed, fall back to PIO */
211 renesas_sdhi_sys_dmac_enable_dma(host, enable: false);
212 if (ret >= 0)
213 ret = -EIO;
214 host->chan_rx = NULL;
215 dma_release_channel(chan);
216 /* Free the Tx channel too */
217 chan = host->chan_tx;
218 if (chan) {
219 host->chan_tx = NULL;
220 dma_release_channel(chan);
221 }
222 dev_warn(&host->pdev->dev,
223 "DMA failed: %d, falling back to PIO\n", ret);
224 }
225}
226
227static void renesas_sdhi_sys_dmac_start_dma_tx(struct tmio_mmc_host *host)
228{
229 struct renesas_sdhi *priv = host_to_priv(host);
230 struct scatterlist *sg = host->sg_ptr, *sg_tmp;
231 struct dma_async_tx_descriptor *desc = NULL;
232 struct dma_chan *chan = host->chan_tx;
233 dma_cookie_t cookie;
234 int ret, i;
235 bool aligned = true, multiple = true;
236 unsigned int align = 1; /* 2-byte alignment */
237
238 for_each_sg(sg, sg_tmp, host->sg_len, i) {
239 if (sg_tmp->offset & align)
240 aligned = false;
241 if (sg_tmp->length & align) {
242 multiple = false;
243 break;
244 }
245 }
246
247 if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_SIZE ||
248 (align & PAGE_MASK))) || !multiple) {
249 ret = -EINVAL;
250 goto pio;
251 }
252
253 if (sg->length < TMIO_MMC_MIN_DMA_LEN)
254 return;
255
256 /* The only sg element can be unaligned, use our bounce buffer then */
257 if (!aligned) {
258 void *sg_vaddr = kmap_local_page(page: sg_page(sg));
259
260 sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
261 memcpy(host->bounce_buf, sg_vaddr + sg->offset, host->bounce_sg.length);
262 kunmap_local(sg_vaddr);
263 host->sg_ptr = &host->bounce_sg;
264 sg = host->sg_ptr;
265 }
266
267 ret = dma_map_sg(chan->device->dev, sg, host->sg_len, DMA_TO_DEVICE);
268 if (ret > 0)
269 desc = dmaengine_prep_slave_sg(chan, sgl: sg, sg_len: ret, dir: DMA_MEM_TO_DEV,
270 flags: DMA_CTRL_ACK);
271
272 if (desc) {
273 reinit_completion(x: &priv->dma_priv.dma_dataend);
274 desc->callback = renesas_sdhi_sys_dmac_dma_callback;
275 desc->callback_param = host;
276
277 cookie = dmaengine_submit(desc);
278 if (cookie < 0) {
279 desc = NULL;
280 ret = cookie;
281 }
282 host->dma_on = true;
283 }
284pio:
285 if (!desc) {
286 /* DMA failed, fall back to PIO */
287 renesas_sdhi_sys_dmac_enable_dma(host, enable: false);
288 if (ret >= 0)
289 ret = -EIO;
290 host->chan_tx = NULL;
291 dma_release_channel(chan);
292 /* Free the Rx channel too */
293 chan = host->chan_rx;
294 if (chan) {
295 host->chan_rx = NULL;
296 dma_release_channel(chan);
297 }
298 dev_warn(&host->pdev->dev,
299 "DMA failed: %d, falling back to PIO\n", ret);
300 }
301}
302
303static void renesas_sdhi_sys_dmac_start_dma(struct tmio_mmc_host *host,
304 struct mmc_data *data)
305{
306 if (data->flags & MMC_DATA_READ) {
307 if (host->chan_rx)
308 renesas_sdhi_sys_dmac_start_dma_rx(host);
309 } else {
310 if (host->chan_tx)
311 renesas_sdhi_sys_dmac_start_dma_tx(host);
312 }
313}
314
315static void renesas_sdhi_sys_dmac_issue_tasklet_fn(unsigned long priv)
316{
317 struct tmio_mmc_host *host = (struct tmio_mmc_host *)priv;
318 struct dma_chan *chan = NULL;
319
320 spin_lock_irq(lock: &host->lock);
321
322 if (host->data) {
323 if (host->data->flags & MMC_DATA_READ)
324 chan = host->chan_rx;
325 else
326 chan = host->chan_tx;
327 }
328
329 spin_unlock_irq(lock: &host->lock);
330
331 tmio_mmc_enable_mmc_irqs(host, TMIO_STAT_DATAEND);
332
333 if (chan)
334 dma_async_issue_pending(chan);
335}
336
337static void renesas_sdhi_sys_dmac_request_dma(struct tmio_mmc_host *host,
338 struct tmio_mmc_data *pdata)
339{
340 struct renesas_sdhi *priv = host_to_priv(host);
341
342 /* We can only either use DMA for both Tx and Rx or not use it at all */
343 if (!host->pdev->dev.of_node &&
344 (!pdata->chan_priv_tx || !pdata->chan_priv_rx))
345 return;
346
347 if (!host->chan_tx && !host->chan_rx) {
348 struct resource *res = platform_get_resource(host->pdev,
349 IORESOURCE_MEM, 0);
350 struct dma_slave_config cfg = {};
351 dma_cap_mask_t mask;
352 int ret;
353
354 if (!res)
355 return;
356
357 dma_cap_zero(mask);
358 dma_cap_set(DMA_SLAVE, mask);
359
360 host->chan_tx = dma_request_slave_channel_compat(mask,
361 fn: priv->dma_priv.filter, fn_param: pdata->chan_priv_tx,
362 dev: &host->pdev->dev, name: "tx");
363 dev_dbg(&host->pdev->dev, "%s: TX: got channel %p\n", __func__,
364 host->chan_tx);
365
366 if (!host->chan_tx)
367 return;
368
369 cfg.direction = DMA_MEM_TO_DEV;
370 cfg.dst_addr = res->start +
371 (CTL_SD_DATA_PORT << host->bus_shift);
372 cfg.dst_addr_width = priv->dma_priv.dma_buswidth;
373 if (!cfg.dst_addr_width)
374 cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
375 cfg.src_addr = 0;
376 ret = dmaengine_slave_config(chan: host->chan_tx, config: &cfg);
377 if (ret < 0)
378 goto ecfgtx;
379
380 host->chan_rx = dma_request_slave_channel_compat(mask,
381 fn: priv->dma_priv.filter, fn_param: pdata->chan_priv_rx,
382 dev: &host->pdev->dev, name: "rx");
383 dev_dbg(&host->pdev->dev, "%s: RX: got channel %p\n", __func__,
384 host->chan_rx);
385
386 if (!host->chan_rx)
387 goto ereqrx;
388
389 cfg.direction = DMA_DEV_TO_MEM;
390 cfg.src_addr = cfg.dst_addr + host->pdata->dma_rx_offset;
391 cfg.src_addr_width = priv->dma_priv.dma_buswidth;
392 if (!cfg.src_addr_width)
393 cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
394 cfg.dst_addr = 0;
395 ret = dmaengine_slave_config(chan: host->chan_rx, config: &cfg);
396 if (ret < 0)
397 goto ecfgrx;
398
399 host->bounce_buf = (u8 *)__get_free_page(GFP_KERNEL | GFP_DMA);
400 if (!host->bounce_buf)
401 goto ebouncebuf;
402
403 init_completion(x: &priv->dma_priv.dma_dataend);
404 tasklet_init(t: &host->dma_issue,
405 func: renesas_sdhi_sys_dmac_issue_tasklet_fn,
406 data: (unsigned long)host);
407 }
408
409 renesas_sdhi_sys_dmac_enable_dma(host, enable: true);
410
411 return;
412
413ebouncebuf:
414ecfgrx:
415 dma_release_channel(chan: host->chan_rx);
416 host->chan_rx = NULL;
417ereqrx:
418ecfgtx:
419 dma_release_channel(chan: host->chan_tx);
420 host->chan_tx = NULL;
421}
422
423static void renesas_sdhi_sys_dmac_release_dma(struct tmio_mmc_host *host)
424{
425 if (host->chan_tx) {
426 struct dma_chan *chan = host->chan_tx;
427
428 host->chan_tx = NULL;
429 dma_release_channel(chan);
430 }
431 if (host->chan_rx) {
432 struct dma_chan *chan = host->chan_rx;
433
434 host->chan_rx = NULL;
435 dma_release_channel(chan);
436 }
437 if (host->bounce_buf) {
438 free_pages(addr: (unsigned long)host->bounce_buf, order: 0);
439 host->bounce_buf = NULL;
440 }
441}
442
443static const struct tmio_mmc_dma_ops renesas_sdhi_sys_dmac_dma_ops = {
444 .start = renesas_sdhi_sys_dmac_start_dma,
445 .enable = renesas_sdhi_sys_dmac_enable_dma,
446 .request = renesas_sdhi_sys_dmac_request_dma,
447 .release = renesas_sdhi_sys_dmac_release_dma,
448 .abort = renesas_sdhi_sys_dmac_abort_dma,
449 .dataend = renesas_sdhi_sys_dmac_dataend_dma,
450};
451
452static int renesas_sdhi_sys_dmac_probe(struct platform_device *pdev)
453{
454 return renesas_sdhi_probe(pdev, dma_ops: &renesas_sdhi_sys_dmac_dma_ops,
455 of_data: of_device_get_match_data(dev: &pdev->dev), NULL);
456}
457
458static const struct dev_pm_ops renesas_sdhi_sys_dmac_dev_pm_ops = {
459 SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
460 pm_runtime_force_resume)
461 SET_RUNTIME_PM_OPS(tmio_mmc_host_runtime_suspend,
462 tmio_mmc_host_runtime_resume,
463 NULL)
464};
465
466static struct platform_driver renesas_sys_dmac_sdhi_driver = {
467 .driver = {
468 .name = "sh_mobile_sdhi",
469 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
470 .pm = &renesas_sdhi_sys_dmac_dev_pm_ops,
471 .of_match_table = renesas_sdhi_sys_dmac_of_match,
472 },
473 .probe = renesas_sdhi_sys_dmac_probe,
474 .remove_new = renesas_sdhi_remove,
475};
476
477module_platform_driver(renesas_sys_dmac_sdhi_driver);
478
479MODULE_DESCRIPTION("Renesas SDHI driver");
480MODULE_AUTHOR("Magnus Damm");
481MODULE_LICENSE("GPL v2");
482MODULE_ALIAS("platform:sh_mobile_sdhi");
483

source code of linux/drivers/mmc/host/renesas_sdhi_sys_dmac.c