xref: /linux/drivers/mmc/host/renesas_sdhi_sys_dmac.c (revision 66e72a01b60ae6950ddbb3585fdc1424d303e14b)
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 	.capabilities	= MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ |
65 			  MMC_CAP_CMD23 | MMC_CAP_WAIT_WHILE_BUSY,
66 	.capabilities2	= MMC_CAP2_NO_WRITE_PROTECT,
67 	.dma_buswidth	= DMA_SLAVE_BUSWIDTH_4_BYTES,
68 	.dma_rx_offset	= 0x2000,
69 	.scc_offset	= 0x0300,
70 	.taps		= rcar_gen2_scc_taps,
71 	.taps_num	= ARRAY_SIZE(rcar_gen2_scc_taps),
72 	.max_blk_count	= UINT_MAX / TMIO_MAX_BLK_SIZE,
73 };
74 
75 static const struct of_device_id renesas_sdhi_sys_dmac_of_match[] = {
76 	{ .compatible = "renesas,sdhi-sh73a0", .data = &of_default_cfg, },
77 	{ .compatible = "renesas,sdhi-r8a73a4", .data = &of_default_cfg, },
78 	{ .compatible = "renesas,sdhi-r8a7740", .data = &of_default_cfg, },
79 	{ .compatible = "renesas,sdhi-r7s72100", .data = &of_rz_compatible, },
80 	{ .compatible = "renesas,sdhi-r8a7778", .data = &of_rcar_gen1_compatible, },
81 	{ .compatible = "renesas,sdhi-r8a7779", .data = &of_rcar_gen1_compatible, },
82 	{ .compatible = "renesas,sdhi-r8a7743", .data = &of_rcar_gen2_compatible, },
83 	{ .compatible = "renesas,sdhi-r8a7745", .data = &of_rcar_gen2_compatible, },
84 	{ .compatible = "renesas,sdhi-r8a7790", .data = &of_rcar_gen2_compatible, },
85 	{ .compatible = "renesas,sdhi-r8a7791", .data = &of_rcar_gen2_compatible, },
86 	{ .compatible = "renesas,sdhi-r8a7792", .data = &of_rcar_gen2_compatible, },
87 	{ .compatible = "renesas,sdhi-r8a7793", .data = &of_rcar_gen2_compatible, },
88 	{ .compatible = "renesas,sdhi-r8a7794", .data = &of_rcar_gen2_compatible, },
89 	{ .compatible = "renesas,rcar-gen1-sdhi", .data = &of_rcar_gen1_compatible, },
90 	{ .compatible = "renesas,rcar-gen2-sdhi", .data = &of_rcar_gen2_compatible, },
91 	{ .compatible = "renesas,sdhi-shmobile" },
92 	{},
93 };
94 MODULE_DEVICE_TABLE(of, renesas_sdhi_sys_dmac_of_match);
95 
96 static void renesas_sdhi_sys_dmac_enable_dma(struct tmio_mmc_host *host,
97 					     bool enable)
98 {
99 	struct renesas_sdhi *priv = host_to_priv(host);
100 
101 	if (!host->chan_tx || !host->chan_rx)
102 		return;
103 
104 	if (priv->dma_priv.enable)
105 		priv->dma_priv.enable(host, enable);
106 }
107 
108 static void renesas_sdhi_sys_dmac_abort_dma(struct tmio_mmc_host *host)
109 {
110 	renesas_sdhi_sys_dmac_enable_dma(host, false);
111 
112 	if (host->chan_rx)
113 		dmaengine_terminate_sync(host->chan_rx);
114 	if (host->chan_tx)
115 		dmaengine_terminate_sync(host->chan_tx);
116 
117 	renesas_sdhi_sys_dmac_enable_dma(host, true);
118 }
119 
120 static void renesas_sdhi_sys_dmac_dataend_dma(struct tmio_mmc_host *host)
121 {
122 	struct renesas_sdhi *priv = host_to_priv(host);
123 
124 	complete(&priv->dma_priv.dma_dataend);
125 }
126 
127 static void renesas_sdhi_sys_dmac_dma_callback(void *arg)
128 {
129 	struct tmio_mmc_host *host = arg;
130 	struct renesas_sdhi *priv = host_to_priv(host);
131 
132 	spin_lock_irq(&host->lock);
133 
134 	if (!host->data)
135 		goto out;
136 
137 	if (host->data->flags & MMC_DATA_READ)
138 		dma_unmap_sg(host->chan_rx->device->dev,
139 			     host->sg_ptr, host->sg_len,
140 			     DMA_FROM_DEVICE);
141 	else
142 		dma_unmap_sg(host->chan_tx->device->dev,
143 			     host->sg_ptr, host->sg_len,
144 			     DMA_TO_DEVICE);
145 
146 	spin_unlock_irq(&host->lock);
147 
148 	wait_for_completion(&priv->dma_priv.dma_dataend);
149 
150 	spin_lock_irq(&host->lock);
151 	tmio_mmc_do_data_irq(host);
152 out:
153 	spin_unlock_irq(&host->lock);
154 }
155 
156 static void renesas_sdhi_sys_dmac_start_dma_rx(struct tmio_mmc_host *host)
157 {
158 	struct renesas_sdhi *priv = host_to_priv(host);
159 	struct scatterlist *sg = host->sg_ptr, *sg_tmp;
160 	struct dma_async_tx_descriptor *desc = NULL;
161 	struct dma_chan *chan = host->chan_rx;
162 	dma_cookie_t cookie;
163 	int ret, i;
164 	bool aligned = true, multiple = true;
165 	unsigned int align = 1;	/* 2-byte alignment */
166 
167 	for_each_sg(sg, sg_tmp, host->sg_len, i) {
168 		if (sg_tmp->offset & align)
169 			aligned = false;
170 		if (sg_tmp->length & align) {
171 			multiple = false;
172 			break;
173 		}
174 	}
175 
176 	if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_SIZE ||
177 			  (align & PAGE_MASK))) || !multiple) {
178 		ret = -EINVAL;
179 		goto pio;
180 	}
181 
182 	if (sg->length < TMIO_MMC_MIN_DMA_LEN)
183 		return;
184 
185 	/* The only sg element can be unaligned, use our bounce buffer then */
186 	if (!aligned) {
187 		sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
188 		host->sg_ptr = &host->bounce_sg;
189 		sg = host->sg_ptr;
190 	}
191 
192 	ret = dma_map_sg(chan->device->dev, sg, host->sg_len, DMA_FROM_DEVICE);
193 	if (ret > 0)
194 		desc = dmaengine_prep_slave_sg(chan, sg, ret, DMA_DEV_TO_MEM,
195 					       DMA_CTRL_ACK);
196 
197 	if (desc) {
198 		reinit_completion(&priv->dma_priv.dma_dataend);
199 		desc->callback = renesas_sdhi_sys_dmac_dma_callback;
200 		desc->callback_param = host;
201 
202 		cookie = dmaengine_submit(desc);
203 		if (cookie < 0) {
204 			desc = NULL;
205 			ret = cookie;
206 		}
207 		host->dma_on = true;
208 	}
209 pio:
210 	if (!desc) {
211 		/* DMA failed, fall back to PIO */
212 		renesas_sdhi_sys_dmac_enable_dma(host, false);
213 		if (ret >= 0)
214 			ret = -EIO;
215 		host->chan_rx = NULL;
216 		dma_release_channel(chan);
217 		/* Free the Tx channel too */
218 		chan = host->chan_tx;
219 		if (chan) {
220 			host->chan_tx = NULL;
221 			dma_release_channel(chan);
222 		}
223 		dev_warn(&host->pdev->dev,
224 			 "DMA failed: %d, falling back to PIO\n", ret);
225 	}
226 }
227 
228 static void renesas_sdhi_sys_dmac_start_dma_tx(struct tmio_mmc_host *host)
229 {
230 	struct renesas_sdhi *priv = host_to_priv(host);
231 	struct scatterlist *sg = host->sg_ptr, *sg_tmp;
232 	struct dma_async_tx_descriptor *desc = NULL;
233 	struct dma_chan *chan = host->chan_tx;
234 	dma_cookie_t cookie;
235 	int ret, i;
236 	bool aligned = true, multiple = true;
237 	unsigned int align = 1;	/* 2-byte alignment */
238 
239 	for_each_sg(sg, sg_tmp, host->sg_len, i) {
240 		if (sg_tmp->offset & align)
241 			aligned = false;
242 		if (sg_tmp->length & align) {
243 			multiple = false;
244 			break;
245 		}
246 	}
247 
248 	if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_SIZE ||
249 			  (align & PAGE_MASK))) || !multiple) {
250 		ret = -EINVAL;
251 		goto pio;
252 	}
253 
254 	if (sg->length < TMIO_MMC_MIN_DMA_LEN)
255 		return;
256 
257 	/* The only sg element can be unaligned, use our bounce buffer then */
258 	if (!aligned) {
259 		void *sg_vaddr = kmap_local_page(sg_page(sg));
260 
261 		sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
262 		memcpy(host->bounce_buf, sg_vaddr + sg->offset, host->bounce_sg.length);
263 		kunmap_local(sg_vaddr);
264 		host->sg_ptr = &host->bounce_sg;
265 		sg = host->sg_ptr;
266 	}
267 
268 	ret = dma_map_sg(chan->device->dev, sg, host->sg_len, DMA_TO_DEVICE);
269 	if (ret > 0)
270 		desc = dmaengine_prep_slave_sg(chan, sg, ret, DMA_MEM_TO_DEV,
271 					       DMA_CTRL_ACK);
272 
273 	if (desc) {
274 		reinit_completion(&priv->dma_priv.dma_dataend);
275 		desc->callback = renesas_sdhi_sys_dmac_dma_callback;
276 		desc->callback_param = host;
277 
278 		cookie = dmaengine_submit(desc);
279 		if (cookie < 0) {
280 			desc = NULL;
281 			ret = cookie;
282 		}
283 		host->dma_on = true;
284 	}
285 pio:
286 	if (!desc) {
287 		/* DMA failed, fall back to PIO */
288 		renesas_sdhi_sys_dmac_enable_dma(host, false);
289 		if (ret >= 0)
290 			ret = -EIO;
291 		host->chan_tx = NULL;
292 		dma_release_channel(chan);
293 		/* Free the Rx channel too */
294 		chan = host->chan_rx;
295 		if (chan) {
296 			host->chan_rx = NULL;
297 			dma_release_channel(chan);
298 		}
299 		dev_warn(&host->pdev->dev,
300 			 "DMA failed: %d, falling back to PIO\n", ret);
301 	}
302 }
303 
304 static void renesas_sdhi_sys_dmac_start_dma(struct tmio_mmc_host *host,
305 					    struct mmc_data *data)
306 {
307 	if (data->flags & MMC_DATA_READ) {
308 		if (host->chan_rx)
309 			renesas_sdhi_sys_dmac_start_dma_rx(host);
310 	} else {
311 		if (host->chan_tx)
312 			renesas_sdhi_sys_dmac_start_dma_tx(host);
313 	}
314 }
315 
316 static void renesas_sdhi_sys_dmac_issue_work_fn(struct work_struct *work)
317 {
318 	struct tmio_mmc_host *host = from_work(host, work, dma_issue);
319 	struct dma_chan *chan = NULL;
320 
321 	spin_lock_irq(&host->lock);
322 
323 	if (host->data) {
324 		if (host->data->flags & MMC_DATA_READ)
325 			chan = host->chan_rx;
326 		else
327 			chan = host->chan_tx;
328 	}
329 
330 	spin_unlock_irq(&host->lock);
331 
332 	tmio_mmc_enable_mmc_irqs(host, TMIO_STAT_DATAEND);
333 
334 	if (chan)
335 		dma_async_issue_pending(chan);
336 }
337 
338 static void renesas_sdhi_sys_dmac_request_dma(struct tmio_mmc_host *host,
339 					      struct tmio_mmc_data *pdata)
340 {
341 	struct renesas_sdhi *priv = host_to_priv(host);
342 
343 	/* We can only either use DMA for both Tx and Rx or not use it at all */
344 	if (!host->pdev->dev.of_node &&
345 	    (!pdata->chan_priv_tx || !pdata->chan_priv_rx))
346 		return;
347 
348 	if (!host->chan_tx && !host->chan_rx) {
349 		struct resource *res = platform_get_resource(host->pdev,
350 							     IORESOURCE_MEM, 0);
351 		struct dma_slave_config cfg = {};
352 		dma_cap_mask_t mask;
353 		int ret;
354 
355 		if (!res)
356 			return;
357 
358 		dma_cap_zero(mask);
359 		dma_cap_set(DMA_SLAVE, mask);
360 
361 		host->chan_tx = dma_request_slave_channel_compat(mask,
362 					priv->dma_priv.filter, pdata->chan_priv_tx,
363 					&host->pdev->dev, "tx");
364 		dev_dbg(&host->pdev->dev, "%s: TX: got channel %p\n", __func__,
365 			host->chan_tx);
366 
367 		if (!host->chan_tx)
368 			return;
369 
370 		cfg.direction = DMA_MEM_TO_DEV;
371 		cfg.dst_addr = res->start +
372 			(CTL_SD_DATA_PORT << host->bus_shift);
373 		cfg.dst_addr_width = priv->dma_priv.dma_buswidth;
374 		if (!cfg.dst_addr_width)
375 			cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
376 		cfg.src_addr = 0;
377 		ret = dmaengine_slave_config(host->chan_tx, &cfg);
378 		if (ret < 0)
379 			goto ecfgtx;
380 
381 		host->chan_rx = dma_request_slave_channel_compat(mask,
382 					priv->dma_priv.filter, pdata->chan_priv_rx,
383 					&host->pdev->dev, "rx");
384 		dev_dbg(&host->pdev->dev, "%s: RX: got channel %p\n", __func__,
385 			host->chan_rx);
386 
387 		if (!host->chan_rx)
388 			goto ereqrx;
389 
390 		cfg.direction = DMA_DEV_TO_MEM;
391 		cfg.src_addr = cfg.dst_addr + host->pdata->dma_rx_offset;
392 		cfg.src_addr_width = priv->dma_priv.dma_buswidth;
393 		if (!cfg.src_addr_width)
394 			cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
395 		cfg.dst_addr = 0;
396 		ret = dmaengine_slave_config(host->chan_rx, &cfg);
397 		if (ret < 0)
398 			goto ecfgrx;
399 
400 		host->bounce_buf = (u8 *)__get_free_page(GFP_KERNEL | GFP_DMA);
401 		if (!host->bounce_buf)
402 			goto ebouncebuf;
403 
404 		init_completion(&priv->dma_priv.dma_dataend);
405 		INIT_WORK(&host->dma_issue,
406 			  renesas_sdhi_sys_dmac_issue_work_fn);
407 	}
408 
409 	renesas_sdhi_sys_dmac_enable_dma(host, true);
410 
411 	return;
412 
413 ebouncebuf:
414 ecfgrx:
415 	dma_release_channel(host->chan_rx);
416 	host->chan_rx = NULL;
417 ereqrx:
418 ecfgtx:
419 	dma_release_channel(host->chan_tx);
420 	host->chan_tx = NULL;
421 }
422 
423 static 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((unsigned long)host->bounce_buf, 0);
439 		host->bounce_buf = NULL;
440 	}
441 }
442 
443 static 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 
452 static int renesas_sdhi_sys_dmac_probe(struct platform_device *pdev)
453 {
454 	return renesas_sdhi_probe(pdev, &renesas_sdhi_sys_dmac_dma_ops,
455 				  of_device_get_match_data(&pdev->dev), NULL);
456 }
457 
458 static 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 
466 static 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 
477 module_platform_driver(renesas_sys_dmac_sdhi_driver);
478 
479 MODULE_DESCRIPTION("Renesas SDHI driver");
480 MODULE_AUTHOR("Magnus Damm");
481 MODULE_LICENSE("GPL v2");
482 MODULE_ALIAS("platform:sh_mobile_sdhi");
483