xref: /linux/drivers/mmc/host/renesas_sdhi_sys_dmac.c (revision d30c1683aaecb93d2ab95685dc4300a33d3cea7a)
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/mmc/host.h>
15 #include <linux/mod_devicetable.h>
16 #include <linux/module.h>
17 #include <linux/of.h>
18 #include <linux/pagemap.h>
19 #include <linux/platform_data/tmio.h>
20 #include <linux/platform_device.h>
21 #include <linux/pm_runtime.h>
22 #include <linux/scatterlist.h>
23 #include <linux/sys_soc.h>
24 
25 #include "renesas_sdhi.h"
26 #include "tmio_mmc.h"
27 
28 #define TMIO_MMC_MIN_DMA_LEN 8
29 
30 static const struct renesas_sdhi_of_data of_default_cfg = {
31 	.tmio_flags = TMIO_MMC_HAS_IDLE_WAIT,
32 };
33 
34 static const struct renesas_sdhi_of_data of_rz_compatible = {
35 	.tmio_flags	= TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_32BIT_DATA_PORT |
36 			  TMIO_MMC_HAVE_CBSY,
37 	.tmio_ocr_mask	= MMC_VDD_32_33,
38 	.capabilities	= MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ |
39 			  MMC_CAP_WAIT_WHILE_BUSY,
40 };
41 
42 static const struct renesas_sdhi_of_data of_rcar_gen1_compatible = {
43 	.tmio_flags	= TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_CLK_ACTUAL,
44 	.capabilities	= MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ |
45 			  MMC_CAP_WAIT_WHILE_BUSY,
46 	.capabilities2	= MMC_CAP2_NO_WRITE_PROTECT,
47 };
48 
49 /* Definitions for sampling clocks */
50 static struct renesas_sdhi_scc rcar_gen2_scc_taps[] = {
51 	{
52 		.clk_rate = 156000000,
53 		.tap = 0x00000703,
54 	},
55 	{
56 		.clk_rate = 0,
57 		.tap = 0x00000300,
58 	},
59 };
60 
61 static const struct renesas_sdhi_of_data of_rcar_gen2_compatible = {
62 	.tmio_flags	= TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_CLK_ACTUAL |
63 			  TMIO_MMC_HAVE_CBSY | TMIO_MMC_MIN_RCAR2 |
64 			  TMIO_MMC_32BIT_DATA_PORT,
65 	.capabilities	= MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ |
66 			  MMC_CAP_CMD23 | MMC_CAP_WAIT_WHILE_BUSY,
67 	.capabilities2	= MMC_CAP2_NO_WRITE_PROTECT,
68 	.dma_buswidth	= DMA_SLAVE_BUSWIDTH_4_BYTES,
69 	.dma_rx_offset	= 0x2000,
70 	.scc_offset	= 0x0300,
71 	.taps		= rcar_gen2_scc_taps,
72 	.taps_num	= ARRAY_SIZE(rcar_gen2_scc_taps),
73 	.max_blk_count	= UINT_MAX / TMIO_MAX_BLK_SIZE,
74 };
75 
76 static const struct of_device_id renesas_sdhi_sys_dmac_of_match[] = {
77 	{ .compatible = "renesas,sdhi-sh73a0", .data = &of_default_cfg, },
78 	{ .compatible = "renesas,sdhi-r8a73a4", .data = &of_default_cfg, },
79 	{ .compatible = "renesas,sdhi-r8a7740", .data = &of_default_cfg, },
80 	{ .compatible = "renesas,sdhi-r7s72100", .data = &of_rz_compatible, },
81 	{ .compatible = "renesas,sdhi-r8a7778", .data = &of_rcar_gen1_compatible, },
82 	{ .compatible = "renesas,sdhi-r8a7779", .data = &of_rcar_gen1_compatible, },
83 	{ .compatible = "renesas,sdhi-r8a7743", .data = &of_rcar_gen2_compatible, },
84 	{ .compatible = "renesas,sdhi-r8a7745", .data = &of_rcar_gen2_compatible, },
85 	{ .compatible = "renesas,sdhi-r8a7790", .data = &of_rcar_gen2_compatible, },
86 	{ .compatible = "renesas,sdhi-r8a7791", .data = &of_rcar_gen2_compatible, },
87 	{ .compatible = "renesas,sdhi-r8a7792", .data = &of_rcar_gen2_compatible, },
88 	{ .compatible = "renesas,sdhi-r8a7793", .data = &of_rcar_gen2_compatible, },
89 	{ .compatible = "renesas,sdhi-r8a7794", .data = &of_rcar_gen2_compatible, },
90 	{ .compatible = "renesas,rcar-gen1-sdhi", .data = &of_rcar_gen1_compatible, },
91 	{ .compatible = "renesas,rcar-gen2-sdhi", .data = &of_rcar_gen2_compatible, },
92 	{ .compatible = "renesas,sdhi-shmobile" },
93 	{},
94 };
95 MODULE_DEVICE_TABLE(of, renesas_sdhi_sys_dmac_of_match);
96 
97 static void renesas_sdhi_sys_dmac_enable_dma(struct tmio_mmc_host *host,
98 					     bool enable)
99 {
100 	struct renesas_sdhi *priv = host_to_priv(host);
101 
102 	if (!host->chan_tx || !host->chan_rx)
103 		return;
104 
105 	if (priv->dma_priv.enable)
106 		priv->dma_priv.enable(host, enable);
107 }
108 
109 static void renesas_sdhi_sys_dmac_abort_dma(struct tmio_mmc_host *host)
110 {
111 	renesas_sdhi_sys_dmac_enable_dma(host, false);
112 
113 	if (host->chan_rx)
114 		dmaengine_terminate_sync(host->chan_rx);
115 	if (host->chan_tx)
116 		dmaengine_terminate_sync(host->chan_tx);
117 
118 	renesas_sdhi_sys_dmac_enable_dma(host, true);
119 }
120 
121 static void renesas_sdhi_sys_dmac_dataend_dma(struct tmio_mmc_host *host)
122 {
123 	struct renesas_sdhi *priv = host_to_priv(host);
124 
125 	complete(&priv->dma_priv.dma_dataend);
126 }
127 
128 static void renesas_sdhi_sys_dmac_dma_callback(void *arg)
129 {
130 	struct tmio_mmc_host *host = arg;
131 	struct renesas_sdhi *priv = host_to_priv(host);
132 
133 	spin_lock_irq(&host->lock);
134 
135 	if (!host->data)
136 		goto out;
137 
138 	if (host->data->flags & MMC_DATA_READ)
139 		dma_unmap_sg(host->chan_rx->device->dev,
140 			     host->sg_ptr, host->sg_len,
141 			     DMA_FROM_DEVICE);
142 	else
143 		dma_unmap_sg(host->chan_tx->device->dev,
144 			     host->sg_ptr, host->sg_len,
145 			     DMA_TO_DEVICE);
146 
147 	spin_unlock_irq(&host->lock);
148 
149 	wait_for_completion(&priv->dma_priv.dma_dataend);
150 
151 	spin_lock_irq(&host->lock);
152 	tmio_mmc_do_data_irq(host);
153 out:
154 	spin_unlock_irq(&host->lock);
155 }
156 
157 static void renesas_sdhi_sys_dmac_start_dma_rx(struct tmio_mmc_host *host)
158 {
159 	struct renesas_sdhi *priv = host_to_priv(host);
160 	struct scatterlist *sg = host->sg_ptr, *sg_tmp;
161 	struct dma_async_tx_descriptor *desc = NULL;
162 	struct dma_chan *chan = host->chan_rx;
163 	dma_cookie_t cookie;
164 	int ret, i;
165 	bool aligned = true, multiple = true;
166 	unsigned int align = 1;	/* 2-byte alignment */
167 
168 	for_each_sg(sg, sg_tmp, host->sg_len, i) {
169 		if (sg_tmp->offset & align)
170 			aligned = false;
171 		if (sg_tmp->length & align) {
172 			multiple = false;
173 			break;
174 		}
175 	}
176 
177 	if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_SIZE ||
178 			  (align & PAGE_MASK))) || !multiple) {
179 		ret = -EINVAL;
180 		goto pio;
181 	}
182 
183 	if (sg->length < TMIO_MMC_MIN_DMA_LEN)
184 		return;
185 
186 	/* The only sg element can be unaligned, use our bounce buffer then */
187 	if (!aligned) {
188 		sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
189 		host->sg_ptr = &host->bounce_sg;
190 		sg = host->sg_ptr;
191 	}
192 
193 	ret = dma_map_sg(chan->device->dev, sg, host->sg_len, DMA_FROM_DEVICE);
194 	if (ret > 0)
195 		desc = dmaengine_prep_slave_sg(chan, sg, ret, DMA_DEV_TO_MEM,
196 					       DMA_CTRL_ACK);
197 
198 	if (desc) {
199 		reinit_completion(&priv->dma_priv.dma_dataend);
200 		desc->callback = renesas_sdhi_sys_dmac_dma_callback;
201 		desc->callback_param = host;
202 
203 		cookie = dmaengine_submit(desc);
204 		if (cookie < 0) {
205 			desc = NULL;
206 			ret = cookie;
207 		}
208 		host->dma_on = true;
209 	}
210 pio:
211 	if (!desc) {
212 		/* DMA failed, fall back to PIO */
213 		renesas_sdhi_sys_dmac_enable_dma(host, false);
214 		if (ret >= 0)
215 			ret = -EIO;
216 		host->chan_rx = NULL;
217 		dma_release_channel(chan);
218 		/* Free the Tx channel too */
219 		chan = host->chan_tx;
220 		if (chan) {
221 			host->chan_tx = NULL;
222 			dma_release_channel(chan);
223 		}
224 		dev_warn(&host->pdev->dev,
225 			 "DMA failed: %d, falling back to PIO\n", ret);
226 	}
227 }
228 
229 static void renesas_sdhi_sys_dmac_start_dma_tx(struct tmio_mmc_host *host)
230 {
231 	struct renesas_sdhi *priv = host_to_priv(host);
232 	struct scatterlist *sg = host->sg_ptr, *sg_tmp;
233 	struct dma_async_tx_descriptor *desc = NULL;
234 	struct dma_chan *chan = host->chan_tx;
235 	dma_cookie_t cookie;
236 	int ret, i;
237 	bool aligned = true, multiple = true;
238 	unsigned int align = 1;	/* 2-byte alignment */
239 
240 	for_each_sg(sg, sg_tmp, host->sg_len, i) {
241 		if (sg_tmp->offset & align)
242 			aligned = false;
243 		if (sg_tmp->length & align) {
244 			multiple = false;
245 			break;
246 		}
247 	}
248 
249 	if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_SIZE ||
250 			  (align & PAGE_MASK))) || !multiple) {
251 		ret = -EINVAL;
252 		goto pio;
253 	}
254 
255 	if (sg->length < TMIO_MMC_MIN_DMA_LEN)
256 		return;
257 
258 	/* The only sg element can be unaligned, use our bounce buffer then */
259 	if (!aligned) {
260 		void *sg_vaddr = kmap_local_page(sg_page(sg));
261 
262 		sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
263 		memcpy(host->bounce_buf, sg_vaddr + sg->offset, host->bounce_sg.length);
264 		kunmap_local(sg_vaddr);
265 		host->sg_ptr = &host->bounce_sg;
266 		sg = host->sg_ptr;
267 	}
268 
269 	ret = dma_map_sg(chan->device->dev, sg, host->sg_len, DMA_TO_DEVICE);
270 	if (ret > 0)
271 		desc = dmaengine_prep_slave_sg(chan, sg, ret, DMA_MEM_TO_DEV,
272 					       DMA_CTRL_ACK);
273 
274 	if (desc) {
275 		reinit_completion(&priv->dma_priv.dma_dataend);
276 		desc->callback = renesas_sdhi_sys_dmac_dma_callback;
277 		desc->callback_param = host;
278 
279 		cookie = dmaengine_submit(desc);
280 		if (cookie < 0) {
281 			desc = NULL;
282 			ret = cookie;
283 		}
284 		host->dma_on = true;
285 	}
286 pio:
287 	if (!desc) {
288 		/* DMA failed, fall back to PIO */
289 		renesas_sdhi_sys_dmac_enable_dma(host, false);
290 		if (ret >= 0)
291 			ret = -EIO;
292 		host->chan_tx = NULL;
293 		dma_release_channel(chan);
294 		/* Free the Rx channel too */
295 		chan = host->chan_rx;
296 		if (chan) {
297 			host->chan_rx = NULL;
298 			dma_release_channel(chan);
299 		}
300 		dev_warn(&host->pdev->dev,
301 			 "DMA failed: %d, falling back to PIO\n", ret);
302 	}
303 }
304 
305 static void renesas_sdhi_sys_dmac_start_dma(struct tmio_mmc_host *host,
306 					    struct mmc_data *data)
307 {
308 	if (data->flags & MMC_DATA_READ) {
309 		if (host->chan_rx)
310 			renesas_sdhi_sys_dmac_start_dma_rx(host);
311 	} else {
312 		if (host->chan_tx)
313 			renesas_sdhi_sys_dmac_start_dma_tx(host);
314 	}
315 }
316 
317 static void renesas_sdhi_sys_dmac_issue_work_fn(struct work_struct *work)
318 {
319 	struct tmio_mmc_host *host = from_work(host, work, dma_issue);
320 	struct dma_chan *chan = NULL;
321 
322 	spin_lock_irq(&host->lock);
323 
324 	if (host->data) {
325 		if (host->data->flags & MMC_DATA_READ)
326 			chan = host->chan_rx;
327 		else
328 			chan = host->chan_tx;
329 	}
330 
331 	spin_unlock_irq(&host->lock);
332 
333 	tmio_mmc_enable_mmc_irqs(host, TMIO_STAT_DATAEND);
334 
335 	if (chan)
336 		dma_async_issue_pending(chan);
337 }
338 
339 static void renesas_sdhi_sys_dmac_request_dma(struct tmio_mmc_host *host,
340 					      struct tmio_mmc_data *pdata)
341 {
342 	struct renesas_sdhi *priv = host_to_priv(host);
343 
344 	/* We can only either use DMA for both Tx and Rx or not use it at all */
345 	if (!host->pdev->dev.of_node &&
346 	    (!pdata->chan_priv_tx || !pdata->chan_priv_rx))
347 		return;
348 
349 	if (!host->chan_tx && !host->chan_rx) {
350 		struct resource *res = platform_get_resource(host->pdev,
351 							     IORESOURCE_MEM, 0);
352 		struct dma_slave_config cfg = {};
353 		dma_cap_mask_t mask;
354 		int ret;
355 
356 		if (!res)
357 			return;
358 
359 		dma_cap_zero(mask);
360 		dma_cap_set(DMA_SLAVE, mask);
361 
362 		host->chan_tx = dma_request_slave_channel_compat(mask,
363 					priv->dma_priv.filter, pdata->chan_priv_tx,
364 					&host->pdev->dev, "tx");
365 		dev_dbg(&host->pdev->dev, "%s: TX: got channel %p\n", __func__,
366 			host->chan_tx);
367 
368 		if (!host->chan_tx)
369 			return;
370 
371 		cfg.direction = DMA_MEM_TO_DEV;
372 		cfg.dst_addr = res->start +
373 			(CTL_SD_DATA_PORT << host->bus_shift);
374 		cfg.dst_addr_width = priv->dma_priv.dma_buswidth;
375 		if (!cfg.dst_addr_width)
376 			cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
377 		cfg.src_addr = 0;
378 		ret = dmaengine_slave_config(host->chan_tx, &cfg);
379 		if (ret < 0)
380 			goto ecfgtx;
381 
382 		host->chan_rx = dma_request_slave_channel_compat(mask,
383 					priv->dma_priv.filter, pdata->chan_priv_rx,
384 					&host->pdev->dev, "rx");
385 		dev_dbg(&host->pdev->dev, "%s: RX: got channel %p\n", __func__,
386 			host->chan_rx);
387 
388 		if (!host->chan_rx)
389 			goto ereqrx;
390 
391 		cfg.direction = DMA_DEV_TO_MEM;
392 		cfg.src_addr = cfg.dst_addr + host->pdata->dma_rx_offset;
393 		cfg.src_addr_width = priv->dma_priv.dma_buswidth;
394 		if (!cfg.src_addr_width)
395 			cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
396 		cfg.dst_addr = 0;
397 		ret = dmaengine_slave_config(host->chan_rx, &cfg);
398 		if (ret < 0)
399 			goto ecfgrx;
400 
401 		host->bounce_buf = (u8 *)__get_free_page(GFP_KERNEL | GFP_DMA);
402 		if (!host->bounce_buf)
403 			goto ebouncebuf;
404 
405 		init_completion(&priv->dma_priv.dma_dataend);
406 		INIT_WORK(&host->dma_issue,
407 			  renesas_sdhi_sys_dmac_issue_work_fn);
408 	}
409 
410 	renesas_sdhi_sys_dmac_enable_dma(host, true);
411 
412 	return;
413 
414 ebouncebuf:
415 ecfgrx:
416 	dma_release_channel(host->chan_rx);
417 	host->chan_rx = NULL;
418 ereqrx:
419 ecfgtx:
420 	dma_release_channel(host->chan_tx);
421 	host->chan_tx = NULL;
422 }
423 
424 static void renesas_sdhi_sys_dmac_release_dma(struct tmio_mmc_host *host)
425 {
426 	if (host->chan_tx) {
427 		struct dma_chan *chan = host->chan_tx;
428 
429 		host->chan_tx = NULL;
430 		dma_release_channel(chan);
431 	}
432 	if (host->chan_rx) {
433 		struct dma_chan *chan = host->chan_rx;
434 
435 		host->chan_rx = NULL;
436 		dma_release_channel(chan);
437 	}
438 	if (host->bounce_buf) {
439 		free_pages((unsigned long)host->bounce_buf, 0);
440 		host->bounce_buf = NULL;
441 	}
442 }
443 
444 static const struct tmio_mmc_dma_ops renesas_sdhi_sys_dmac_dma_ops = {
445 	.start = renesas_sdhi_sys_dmac_start_dma,
446 	.enable = renesas_sdhi_sys_dmac_enable_dma,
447 	.request = renesas_sdhi_sys_dmac_request_dma,
448 	.release = renesas_sdhi_sys_dmac_release_dma,
449 	.abort = renesas_sdhi_sys_dmac_abort_dma,
450 	.dataend = renesas_sdhi_sys_dmac_dataend_dma,
451 };
452 
453 static int renesas_sdhi_sys_dmac_probe(struct platform_device *pdev)
454 {
455 	return renesas_sdhi_probe(pdev, &renesas_sdhi_sys_dmac_dma_ops,
456 				  of_device_get_match_data(&pdev->dev), NULL);
457 }
458 
459 static const struct dev_pm_ops renesas_sdhi_sys_dmac_dev_pm_ops = {
460 	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
461 				pm_runtime_force_resume)
462 	SET_RUNTIME_PM_OPS(tmio_mmc_host_runtime_suspend,
463 			   tmio_mmc_host_runtime_resume,
464 			   NULL)
465 };
466 
467 static struct platform_driver renesas_sys_dmac_sdhi_driver = {
468 	.driver		= {
469 		.name	= "sh_mobile_sdhi",
470 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
471 		.pm	= &renesas_sdhi_sys_dmac_dev_pm_ops,
472 		.of_match_table = renesas_sdhi_sys_dmac_of_match,
473 	},
474 	.probe		= renesas_sdhi_sys_dmac_probe,
475 	.remove		= renesas_sdhi_remove,
476 };
477 
478 module_platform_driver(renesas_sys_dmac_sdhi_driver);
479 
480 MODULE_DESCRIPTION("Renesas SDHI driver");
481 MODULE_AUTHOR("Magnus Damm");
482 MODULE_LICENSE("GPL v2");
483 MODULE_ALIAS("platform:sh_mobile_sdhi");
484