1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2013-2014 Renesas Electronics Europe Ltd.
4  * Author: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
5  */
6 
7 #include <linux/clk.h>
8 #include <linux/delay.h>
9 #include <linux/device.h>
10 #include <linux/dma-mapping.h>
11 #include <linux/dmaengine.h>
12 #include <linux/highmem.h>
13 #include <linux/interrupt.h>
14 #include <linux/io.h>
15 #include <linux/log2.h>
16 #include <linux/mmc/host.h>
17 #include <linux/mmc/mmc.h>
18 #include <linux/mmc/sd.h>
19 #include <linux/mmc/sdio.h>
20 #include <linux/module.h>
21 #include <linux/pagemap.h>
22 #include <linux/pinctrl/consumer.h>
23 #include <linux/platform_device.h>
24 #include <linux/scatterlist.h>
25 #include <linux/string.h>
26 #include <linux/time.h>
27 #include <linux/virtio.h>
28 #include <linux/workqueue.h>
29 
30 #define USDHI6_SD_CMD		0x0000
31 #define USDHI6_SD_PORT_SEL	0x0004
32 #define USDHI6_SD_ARG		0x0008
33 #define USDHI6_SD_STOP		0x0010
34 #define USDHI6_SD_SECCNT	0x0014
35 #define USDHI6_SD_RSP10		0x0018
36 #define USDHI6_SD_RSP32		0x0020
37 #define USDHI6_SD_RSP54		0x0028
38 #define USDHI6_SD_RSP76		0x0030
39 #define USDHI6_SD_INFO1		0x0038
40 #define USDHI6_SD_INFO2		0x003c
41 #define USDHI6_SD_INFO1_MASK	0x0040
42 #define USDHI6_SD_INFO2_MASK	0x0044
43 #define USDHI6_SD_CLK_CTRL	0x0048
44 #define USDHI6_SD_SIZE		0x004c
45 #define USDHI6_SD_OPTION	0x0050
46 #define USDHI6_SD_ERR_STS1	0x0058
47 #define USDHI6_SD_ERR_STS2	0x005c
48 #define USDHI6_SD_BUF0		0x0060
49 #define USDHI6_SDIO_MODE	0x0068
50 #define USDHI6_SDIO_INFO1	0x006c
51 #define USDHI6_SDIO_INFO1_MASK	0x0070
52 #define USDHI6_CC_EXT_MODE	0x01b0
53 #define USDHI6_SOFT_RST		0x01c0
54 #define USDHI6_VERSION		0x01c4
55 #define USDHI6_HOST_MODE	0x01c8
56 #define USDHI6_SDIF_MODE	0x01cc
57 
58 #define USDHI6_SD_CMD_APP		0x0040
59 #define USDHI6_SD_CMD_MODE_RSP_AUTO	0x0000
60 #define USDHI6_SD_CMD_MODE_RSP_NONE	0x0300
61 #define USDHI6_SD_CMD_MODE_RSP_R1	0x0400	/* Also R5, R6, R7 */
62 #define USDHI6_SD_CMD_MODE_RSP_R1B	0x0500	/* R1b */
63 #define USDHI6_SD_CMD_MODE_RSP_R2	0x0600
64 #define USDHI6_SD_CMD_MODE_RSP_R3	0x0700	/* Also R4 */
65 #define USDHI6_SD_CMD_DATA		0x0800
66 #define USDHI6_SD_CMD_READ		0x1000
67 #define USDHI6_SD_CMD_MULTI		0x2000
68 #define USDHI6_SD_CMD_CMD12_AUTO_OFF	0x4000
69 
70 #define USDHI6_CC_EXT_MODE_SDRW		BIT(1)
71 
72 #define USDHI6_SD_INFO1_RSP_END		BIT(0)
73 #define USDHI6_SD_INFO1_ACCESS_END	BIT(2)
74 #define USDHI6_SD_INFO1_CARD_OUT	BIT(3)
75 #define USDHI6_SD_INFO1_CARD_IN		BIT(4)
76 #define USDHI6_SD_INFO1_CD		BIT(5)
77 #define USDHI6_SD_INFO1_WP		BIT(7)
78 #define USDHI6_SD_INFO1_D3_CARD_OUT	BIT(8)
79 #define USDHI6_SD_INFO1_D3_CARD_IN	BIT(9)
80 
81 #define USDHI6_SD_INFO2_CMD_ERR		BIT(0)
82 #define USDHI6_SD_INFO2_CRC_ERR		BIT(1)
83 #define USDHI6_SD_INFO2_END_ERR		BIT(2)
84 #define USDHI6_SD_INFO2_TOUT		BIT(3)
85 #define USDHI6_SD_INFO2_IWA_ERR		BIT(4)
86 #define USDHI6_SD_INFO2_IRA_ERR		BIT(5)
87 #define USDHI6_SD_INFO2_RSP_TOUT	BIT(6)
88 #define USDHI6_SD_INFO2_SDDAT0		BIT(7)
89 #define USDHI6_SD_INFO2_BRE		BIT(8)
90 #define USDHI6_SD_INFO2_BWE		BIT(9)
91 #define USDHI6_SD_INFO2_SCLKDIVEN	BIT(13)
92 #define USDHI6_SD_INFO2_CBSY		BIT(14)
93 #define USDHI6_SD_INFO2_ILA		BIT(15)
94 
95 #define USDHI6_SD_INFO1_CARD_INSERT (USDHI6_SD_INFO1_CARD_IN | USDHI6_SD_INFO1_D3_CARD_IN)
96 #define USDHI6_SD_INFO1_CARD_EJECT (USDHI6_SD_INFO1_CARD_OUT | USDHI6_SD_INFO1_D3_CARD_OUT)
97 #define USDHI6_SD_INFO1_CARD (USDHI6_SD_INFO1_CARD_INSERT | USDHI6_SD_INFO1_CARD_EJECT)
98 #define USDHI6_SD_INFO1_CARD_CD (USDHI6_SD_INFO1_CARD_IN | USDHI6_SD_INFO1_CARD_OUT)
99 
100 #define USDHI6_SD_INFO2_ERR	(USDHI6_SD_INFO2_CMD_ERR |	\
101 	USDHI6_SD_INFO2_CRC_ERR | USDHI6_SD_INFO2_END_ERR |	\
102 	USDHI6_SD_INFO2_TOUT | USDHI6_SD_INFO2_IWA_ERR |	\
103 	USDHI6_SD_INFO2_IRA_ERR | USDHI6_SD_INFO2_RSP_TOUT |	\
104 	USDHI6_SD_INFO2_ILA)
105 
106 #define USDHI6_SD_INFO1_IRQ	(USDHI6_SD_INFO1_RSP_END | USDHI6_SD_INFO1_ACCESS_END | \
107 				 USDHI6_SD_INFO1_CARD)
108 
109 #define USDHI6_SD_INFO2_IRQ	(USDHI6_SD_INFO2_ERR | USDHI6_SD_INFO2_BRE | \
110 				 USDHI6_SD_INFO2_BWE | 0x0800 | USDHI6_SD_INFO2_ILA)
111 
112 #define USDHI6_SD_CLK_CTRL_SCLKEN	BIT(8)
113 
114 #define USDHI6_SD_STOP_STP		BIT(0)
115 #define USDHI6_SD_STOP_SEC		BIT(8)
116 
117 #define USDHI6_SDIO_INFO1_IOIRQ		BIT(0)
118 #define USDHI6_SDIO_INFO1_EXPUB52	BIT(14)
119 #define USDHI6_SDIO_INFO1_EXWT		BIT(15)
120 
121 #define USDHI6_SD_ERR_STS1_CRC_NO_ERROR	BIT(13)
122 
123 #define USDHI6_SOFT_RST_RESERVED	(BIT(1) | BIT(2))
124 #define USDHI6_SOFT_RST_RESET		BIT(0)
125 
126 #define USDHI6_SD_OPTION_TIMEOUT_SHIFT	4
127 #define USDHI6_SD_OPTION_TIMEOUT_MASK	(0xf << USDHI6_SD_OPTION_TIMEOUT_SHIFT)
128 #define USDHI6_SD_OPTION_WIDTH_1	BIT(15)
129 
130 #define USDHI6_SD_PORT_SEL_PORTS_SHIFT	8
131 
132 #define USDHI6_SD_CLK_CTRL_DIV_MASK	0xff
133 
134 #define USDHI6_SDIO_INFO1_IRQ	(USDHI6_SDIO_INFO1_IOIRQ | 3 | \
135 				 USDHI6_SDIO_INFO1_EXPUB52 | USDHI6_SDIO_INFO1_EXWT)
136 
137 #define USDHI6_MIN_DMA 64
138 
139 #define USDHI6_REQ_TIMEOUT_MS 4000
140 
141 enum usdhi6_wait_for {
142 	USDHI6_WAIT_FOR_REQUEST,
143 	USDHI6_WAIT_FOR_CMD,
144 	USDHI6_WAIT_FOR_MREAD,
145 	USDHI6_WAIT_FOR_MWRITE,
146 	USDHI6_WAIT_FOR_READ,
147 	USDHI6_WAIT_FOR_WRITE,
148 	USDHI6_WAIT_FOR_DATA_END,
149 	USDHI6_WAIT_FOR_STOP,
150 	USDHI6_WAIT_FOR_DMA,
151 };
152 
153 struct usdhi6_page {
154 	struct page *page;
155 	void *mapped;		/* mapped page */
156 };
157 
158 struct usdhi6_host {
159 	struct mmc_host *mmc;
160 	struct mmc_request *mrq;
161 	void __iomem *base;
162 	struct clk *clk;
163 
164 	/* SG memory handling */
165 
166 	/* Common for multiple and single block requests */
167 	struct usdhi6_page pg;	/* current page from an SG */
168 	void *blk_page;		/* either a mapped page, or the bounce buffer */
169 	size_t offset;		/* offset within a page, including sg->offset */
170 
171 	/* Blocks, crossing a page boundary */
172 	size_t head_len;
173 	struct usdhi6_page head_pg;
174 
175 	/* A bounce buffer for unaligned blocks or blocks, crossing a page boundary */
176 	struct scatterlist bounce_sg;
177 	u8 bounce_buf[512];
178 
179 	/* Multiple block requests only */
180 	struct scatterlist *sg;	/* current SG segment */
181 	int page_idx;		/* page index within an SG segment */
182 
183 	enum usdhi6_wait_for wait;
184 	u32 status_mask;
185 	u32 status2_mask;
186 	u32 sdio_mask;
187 	u32 io_error;
188 	u32 irq_status;
189 	unsigned long imclk;
190 	unsigned long rate;
191 	bool app_cmd;
192 
193 	/* Timeout handling */
194 	struct delayed_work timeout_work;
195 	unsigned long timeout;
196 
197 	/* DMA support */
198 	struct dma_chan *chan_rx;
199 	struct dma_chan *chan_tx;
200 	bool dma_active;
201 
202 	/* Pin control */
203 	struct pinctrl *pinctrl;
204 	struct pinctrl_state *pins_uhs;
205 };
206 
207 /*			I/O primitives					*/
208 
usdhi6_write(struct usdhi6_host * host,u32 reg,u32 data)209 static void usdhi6_write(struct usdhi6_host *host, u32 reg, u32 data)
210 {
211 	iowrite32(data, host->base + reg);
212 	dev_vdbg(mmc_dev(host->mmc), "%s(0x%p + 0x%x) = 0x%x\n", __func__,
213 		host->base, reg, data);
214 }
215 
usdhi6_write16(struct usdhi6_host * host,u32 reg,u16 data)216 static void usdhi6_write16(struct usdhi6_host *host, u32 reg, u16 data)
217 {
218 	iowrite16(data, host->base + reg);
219 	dev_vdbg(mmc_dev(host->mmc), "%s(0x%p + 0x%x) = 0x%x\n", __func__,
220 		host->base, reg, data);
221 }
222 
usdhi6_read(struct usdhi6_host * host,u32 reg)223 static u32 usdhi6_read(struct usdhi6_host *host, u32 reg)
224 {
225 	u32 data = ioread32(host->base + reg);
226 	dev_vdbg(mmc_dev(host->mmc), "%s(0x%p + 0x%x) = 0x%x\n", __func__,
227 		host->base, reg, data);
228 	return data;
229 }
230 
usdhi6_read16(struct usdhi6_host * host,u32 reg)231 static u16 usdhi6_read16(struct usdhi6_host *host, u32 reg)
232 {
233 	u16 data = ioread16(host->base + reg);
234 	dev_vdbg(mmc_dev(host->mmc), "%s(0x%p + 0x%x) = 0x%x\n", __func__,
235 		host->base, reg, data);
236 	return data;
237 }
238 
usdhi6_irq_enable(struct usdhi6_host * host,u32 info1,u32 info2)239 static void usdhi6_irq_enable(struct usdhi6_host *host, u32 info1, u32 info2)
240 {
241 	host->status_mask = USDHI6_SD_INFO1_IRQ & ~info1;
242 	host->status2_mask = USDHI6_SD_INFO2_IRQ & ~info2;
243 	usdhi6_write(host, USDHI6_SD_INFO1_MASK, host->status_mask);
244 	usdhi6_write(host, USDHI6_SD_INFO2_MASK, host->status2_mask);
245 }
246 
usdhi6_wait_for_resp(struct usdhi6_host * host)247 static void usdhi6_wait_for_resp(struct usdhi6_host *host)
248 {
249 	usdhi6_irq_enable(host, USDHI6_SD_INFO1_RSP_END |
250 			  USDHI6_SD_INFO1_ACCESS_END | USDHI6_SD_INFO1_CARD_CD,
251 			  USDHI6_SD_INFO2_ERR);
252 }
253 
usdhi6_wait_for_brwe(struct usdhi6_host * host,bool read)254 static void usdhi6_wait_for_brwe(struct usdhi6_host *host, bool read)
255 {
256 	usdhi6_irq_enable(host, USDHI6_SD_INFO1_ACCESS_END |
257 			  USDHI6_SD_INFO1_CARD_CD, USDHI6_SD_INFO2_ERR |
258 			  (read ? USDHI6_SD_INFO2_BRE : USDHI6_SD_INFO2_BWE));
259 }
260 
usdhi6_only_cd(struct usdhi6_host * host)261 static void usdhi6_only_cd(struct usdhi6_host *host)
262 {
263 	/* Mask all except card hotplug */
264 	usdhi6_irq_enable(host, USDHI6_SD_INFO1_CARD_CD, 0);
265 }
266 
usdhi6_mask_all(struct usdhi6_host * host)267 static void usdhi6_mask_all(struct usdhi6_host *host)
268 {
269 	usdhi6_irq_enable(host, 0, 0);
270 }
271 
usdhi6_error_code(struct usdhi6_host * host)272 static int usdhi6_error_code(struct usdhi6_host *host)
273 {
274 	u32 err;
275 
276 	usdhi6_write(host, USDHI6_SD_STOP, USDHI6_SD_STOP_STP);
277 
278 	if (host->io_error &
279 	    (USDHI6_SD_INFO2_RSP_TOUT | USDHI6_SD_INFO2_TOUT)) {
280 		u32 rsp54 = usdhi6_read(host, USDHI6_SD_RSP54);
281 		int opc = host->mrq ? host->mrq->cmd->opcode : -1;
282 
283 		err = usdhi6_read(host, USDHI6_SD_ERR_STS2);
284 		/* Response timeout is often normal, don't spam the log */
285 		if (host->wait == USDHI6_WAIT_FOR_CMD)
286 			dev_dbg(mmc_dev(host->mmc),
287 				"T-out sts 0x%x, resp 0x%x, state %u, CMD%d\n",
288 				err, rsp54, host->wait, opc);
289 		else
290 			dev_warn(mmc_dev(host->mmc),
291 				 "T-out sts 0x%x, resp 0x%x, state %u, CMD%d\n",
292 				 err, rsp54, host->wait, opc);
293 		return -ETIMEDOUT;
294 	}
295 
296 	err = usdhi6_read(host, USDHI6_SD_ERR_STS1);
297 	if (err != USDHI6_SD_ERR_STS1_CRC_NO_ERROR)
298 		dev_warn(mmc_dev(host->mmc), "Err sts 0x%x, state %u, CMD%d\n",
299 			 err, host->wait, host->mrq ? host->mrq->cmd->opcode : -1);
300 	if (host->io_error & USDHI6_SD_INFO2_ILA)
301 		return -EILSEQ;
302 
303 	return -EIO;
304 }
305 
306 /*			Scatter-Gather management			*/
307 
308 /*
309  * In PIO mode we have to map each page separately, using kmap(). That way
310  * adjacent pages are mapped to non-adjacent virtual addresses. That's why we
311  * have to use a bounce buffer for blocks, crossing page boundaries. Such blocks
312  * have been observed with an SDIO WiFi card (b43 driver).
313  */
usdhi6_blk_bounce(struct usdhi6_host * host,struct scatterlist * sg)314 static void usdhi6_blk_bounce(struct usdhi6_host *host,
315 			      struct scatterlist *sg)
316 {
317 	struct mmc_data *data = host->mrq->data;
318 	size_t blk_head = host->head_len;
319 
320 	dev_dbg(mmc_dev(host->mmc), "%s(): CMD%u of %u SG: %ux%u @ 0x%x\n",
321 		__func__, host->mrq->cmd->opcode, data->sg_len,
322 		data->blksz, data->blocks, sg->offset);
323 
324 	host->head_pg.page	= host->pg.page;
325 	host->head_pg.mapped	= host->pg.mapped;
326 	host->pg.page		= nth_page(host->pg.page, 1);
327 	host->pg.mapped		= kmap(host->pg.page);
328 
329 	host->blk_page = host->bounce_buf;
330 	host->offset = 0;
331 
332 	if (data->flags & MMC_DATA_READ)
333 		return;
334 
335 	memcpy(host->bounce_buf, host->head_pg.mapped + PAGE_SIZE - blk_head,
336 	       blk_head);
337 	memcpy(host->bounce_buf + blk_head, host->pg.mapped,
338 	       data->blksz - blk_head);
339 }
340 
341 /* Only called for multiple block IO */
usdhi6_sg_prep(struct usdhi6_host * host)342 static void usdhi6_sg_prep(struct usdhi6_host *host)
343 {
344 	struct mmc_request *mrq = host->mrq;
345 	struct mmc_data *data = mrq->data;
346 
347 	usdhi6_write(host, USDHI6_SD_SECCNT, data->blocks);
348 
349 	host->sg = data->sg;
350 	/* TODO: if we always map, this is redundant */
351 	host->offset = host->sg->offset;
352 }
353 
354 /* Map the first page in an SG segment: common for multiple and single block IO */
usdhi6_sg_map(struct usdhi6_host * host)355 static void *usdhi6_sg_map(struct usdhi6_host *host)
356 {
357 	struct mmc_data *data = host->mrq->data;
358 	struct scatterlist *sg = data->sg_len > 1 ? host->sg : data->sg;
359 	size_t head = PAGE_SIZE - sg->offset;
360 	size_t blk_head = head % data->blksz;
361 
362 	WARN(host->pg.page, "%p not properly unmapped!\n", host->pg.page);
363 	if (WARN(sg_dma_len(sg) % data->blksz,
364 		 "SG size %u isn't a multiple of block size %u\n",
365 		 sg_dma_len(sg), data->blksz))
366 		return NULL;
367 
368 	host->pg.page = sg_page(sg);
369 	host->pg.mapped = kmap(host->pg.page);
370 	host->offset = sg->offset;
371 
372 	/*
373 	 * Block size must be a power of 2 for multi-block transfers,
374 	 * therefore blk_head is equal for all pages in this SG
375 	 */
376 	host->head_len = blk_head;
377 
378 	if (head < data->blksz)
379 		/*
380 		 * The first block in the SG crosses a page boundary.
381 		 * Max blksz = 512, so blocks can only span 2 pages
382 		 */
383 		usdhi6_blk_bounce(host, sg);
384 	else
385 		host->blk_page = host->pg.mapped;
386 
387 	dev_dbg(mmc_dev(host->mmc), "Mapped %p (%lx) at %p + %u for CMD%u @ 0x%p\n",
388 		host->pg.page, page_to_pfn(host->pg.page), host->pg.mapped,
389 		sg->offset, host->mrq->cmd->opcode, host->mrq);
390 
391 	return host->blk_page + host->offset;
392 }
393 
394 /* Unmap the current page: common for multiple and single block IO */
usdhi6_sg_unmap(struct usdhi6_host * host,bool force)395 static void usdhi6_sg_unmap(struct usdhi6_host *host, bool force)
396 {
397 	struct mmc_data *data = host->mrq->data;
398 	struct page *page = host->head_pg.page;
399 
400 	if (page) {
401 		/* Previous block was cross-page boundary */
402 		struct scatterlist *sg = data->sg_len > 1 ?
403 			host->sg : data->sg;
404 		size_t blk_head = host->head_len;
405 
406 		if (!data->error && data->flags & MMC_DATA_READ) {
407 			memcpy(host->head_pg.mapped + PAGE_SIZE - blk_head,
408 			       host->bounce_buf, blk_head);
409 			memcpy(host->pg.mapped, host->bounce_buf + blk_head,
410 			       data->blksz - blk_head);
411 		}
412 
413 		flush_dcache_page(page);
414 		kunmap(page);
415 
416 		host->head_pg.page = NULL;
417 
418 		if (!force && sg_dma_len(sg) + sg->offset >
419 		    (host->page_idx << PAGE_SHIFT) + data->blksz - blk_head)
420 			/* More blocks in this SG, don't unmap the next page */
421 			return;
422 	}
423 
424 	page = host->pg.page;
425 	if (!page)
426 		return;
427 
428 	flush_dcache_page(page);
429 	kunmap(page);
430 
431 	host->pg.page = NULL;
432 }
433 
434 /* Called from MMC_WRITE_MULTIPLE_BLOCK or MMC_READ_MULTIPLE_BLOCK */
usdhi6_sg_advance(struct usdhi6_host * host)435 static void usdhi6_sg_advance(struct usdhi6_host *host)
436 {
437 	struct mmc_data *data = host->mrq->data;
438 	size_t done, total;
439 
440 	/* New offset: set at the end of the previous block */
441 	if (host->head_pg.page) {
442 		/* Finished a cross-page block, jump to the new page */
443 		host->page_idx++;
444 		host->offset = data->blksz - host->head_len;
445 		host->blk_page = host->pg.mapped;
446 		usdhi6_sg_unmap(host, false);
447 	} else {
448 		host->offset += data->blksz;
449 		/* The completed block didn't cross a page boundary */
450 		if (host->offset == PAGE_SIZE) {
451 			/* If required, we'll map the page below */
452 			host->offset = 0;
453 			host->page_idx++;
454 		}
455 	}
456 
457 	/*
458 	 * Now host->blk_page + host->offset point at the end of our last block
459 	 * and host->page_idx is the index of the page, in which our new block
460 	 * is located, if any
461 	 */
462 
463 	done = (host->page_idx << PAGE_SHIFT) + host->offset;
464 	total = host->sg->offset + sg_dma_len(host->sg);
465 
466 	dev_dbg(mmc_dev(host->mmc), "%s(): %zu of %zu @ %zu\n", __func__,
467 		done, total, host->offset);
468 
469 	if (done < total && host->offset) {
470 		/* More blocks in this page */
471 		if (host->offset + data->blksz > PAGE_SIZE)
472 			/* We approached at a block, that spans 2 pages */
473 			usdhi6_blk_bounce(host, host->sg);
474 
475 		return;
476 	}
477 
478 	/* Finished current page or an SG segment */
479 	usdhi6_sg_unmap(host, false);
480 
481 	if (done == total) {
482 		/*
483 		 * End of an SG segment or the complete SG: jump to the next
484 		 * segment, we'll map it later in usdhi6_blk_read() or
485 		 * usdhi6_blk_write()
486 		 */
487 		struct scatterlist *next = sg_next(host->sg);
488 
489 		host->page_idx = 0;
490 
491 		if (!next)
492 			host->wait = USDHI6_WAIT_FOR_DATA_END;
493 		host->sg = next;
494 
495 		if (WARN(next && sg_dma_len(next) % data->blksz,
496 			 "SG size %u isn't a multiple of block size %u\n",
497 			 sg_dma_len(next), data->blksz))
498 			data->error = -EINVAL;
499 
500 		return;
501 	}
502 
503 	/* We cannot get here after crossing a page border */
504 
505 	/* Next page in the same SG */
506 	host->pg.page = nth_page(sg_page(host->sg), host->page_idx);
507 	host->pg.mapped = kmap(host->pg.page);
508 	host->blk_page = host->pg.mapped;
509 
510 	dev_dbg(mmc_dev(host->mmc), "Mapped %p (%lx) at %p for CMD%u @ 0x%p\n",
511 		host->pg.page, page_to_pfn(host->pg.page), host->pg.mapped,
512 		host->mrq->cmd->opcode, host->mrq);
513 }
514 
515 /*			DMA handling					*/
516 
usdhi6_dma_release(struct usdhi6_host * host)517 static void usdhi6_dma_release(struct usdhi6_host *host)
518 {
519 	host->dma_active = false;
520 	if (host->chan_tx) {
521 		struct dma_chan *chan = host->chan_tx;
522 		host->chan_tx = NULL;
523 		dma_release_channel(chan);
524 	}
525 	if (host->chan_rx) {
526 		struct dma_chan *chan = host->chan_rx;
527 		host->chan_rx = NULL;
528 		dma_release_channel(chan);
529 	}
530 }
531 
usdhi6_dma_stop_unmap(struct usdhi6_host * host)532 static void usdhi6_dma_stop_unmap(struct usdhi6_host *host)
533 {
534 	struct mmc_data *data = host->mrq->data;
535 
536 	if (!host->dma_active)
537 		return;
538 
539 	usdhi6_write(host, USDHI6_CC_EXT_MODE, 0);
540 	host->dma_active = false;
541 
542 	if (data->flags & MMC_DATA_READ)
543 		dma_unmap_sg(host->chan_rx->device->dev, data->sg,
544 			     data->sg_len, DMA_FROM_DEVICE);
545 	else
546 		dma_unmap_sg(host->chan_tx->device->dev, data->sg,
547 			     data->sg_len, DMA_TO_DEVICE);
548 }
549 
usdhi6_dma_complete(void * arg)550 static void usdhi6_dma_complete(void *arg)
551 {
552 	struct usdhi6_host *host = arg;
553 	struct mmc_request *mrq = host->mrq;
554 
555 	if (WARN(!mrq || !mrq->data, "%s: NULL data in DMA completion for %p!\n",
556 		 dev_name(mmc_dev(host->mmc)), mrq))
557 		return;
558 
559 	dev_dbg(mmc_dev(host->mmc), "%s(): CMD%u DMA completed\n", __func__,
560 		mrq->cmd->opcode);
561 
562 	usdhi6_dma_stop_unmap(host);
563 	usdhi6_wait_for_brwe(host, mrq->data->flags & MMC_DATA_READ);
564 }
565 
usdhi6_dma_setup(struct usdhi6_host * host,struct dma_chan * chan,enum dma_transfer_direction dir)566 static int usdhi6_dma_setup(struct usdhi6_host *host, struct dma_chan *chan,
567 			    enum dma_transfer_direction dir)
568 {
569 	struct mmc_data *data = host->mrq->data;
570 	struct scatterlist *sg = data->sg;
571 	struct dma_async_tx_descriptor *desc = NULL;
572 	dma_cookie_t cookie = -EINVAL;
573 	enum dma_data_direction data_dir;
574 	int ret;
575 
576 	switch (dir) {
577 	case DMA_MEM_TO_DEV:
578 		data_dir = DMA_TO_DEVICE;
579 		break;
580 	case DMA_DEV_TO_MEM:
581 		data_dir = DMA_FROM_DEVICE;
582 		break;
583 	default:
584 		return -EINVAL;
585 	}
586 
587 	ret = dma_map_sg(chan->device->dev, sg, data->sg_len, data_dir);
588 	if (ret > 0) {
589 		host->dma_active = true;
590 		desc = dmaengine_prep_slave_sg(chan, sg, ret, dir,
591 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
592 	}
593 
594 	if (desc) {
595 		desc->callback = usdhi6_dma_complete;
596 		desc->callback_param = host;
597 		cookie = dmaengine_submit(desc);
598 	}
599 
600 	dev_dbg(mmc_dev(host->mmc), "%s(): mapped %d -> %d, cookie %d @ %p\n",
601 		__func__, data->sg_len, ret, cookie, desc);
602 
603 	if (cookie < 0) {
604 		/* DMA failed, fall back to PIO */
605 		if (ret >= 0)
606 			ret = cookie;
607 		usdhi6_dma_release(host);
608 		dev_warn(mmc_dev(host->mmc),
609 			 "DMA failed: %d, falling back to PIO\n", ret);
610 	}
611 
612 	return cookie;
613 }
614 
usdhi6_dma_start(struct usdhi6_host * host)615 static int usdhi6_dma_start(struct usdhi6_host *host)
616 {
617 	if (!host->chan_rx || !host->chan_tx)
618 		return -ENODEV;
619 
620 	if (host->mrq->data->flags & MMC_DATA_READ)
621 		return usdhi6_dma_setup(host, host->chan_rx, DMA_DEV_TO_MEM);
622 
623 	return usdhi6_dma_setup(host, host->chan_tx, DMA_MEM_TO_DEV);
624 }
625 
usdhi6_dma_kill(struct usdhi6_host * host)626 static void usdhi6_dma_kill(struct usdhi6_host *host)
627 {
628 	struct mmc_data *data = host->mrq->data;
629 
630 	dev_dbg(mmc_dev(host->mmc), "%s(): SG of %u: %ux%u\n",
631 		__func__, data->sg_len, data->blocks, data->blksz);
632 	/* Abort DMA */
633 	if (data->flags & MMC_DATA_READ)
634 		dmaengine_terminate_sync(host->chan_rx);
635 	else
636 		dmaengine_terminate_sync(host->chan_tx);
637 }
638 
usdhi6_dma_check_error(struct usdhi6_host * host)639 static void usdhi6_dma_check_error(struct usdhi6_host *host)
640 {
641 	struct mmc_data *data = host->mrq->data;
642 
643 	dev_dbg(mmc_dev(host->mmc), "%s(): IO error %d, status 0x%x\n",
644 		__func__, host->io_error, usdhi6_read(host, USDHI6_SD_INFO1));
645 
646 	if (host->io_error) {
647 		data->error = usdhi6_error_code(host);
648 		data->bytes_xfered = 0;
649 		usdhi6_dma_kill(host);
650 		usdhi6_dma_release(host);
651 		dev_warn(mmc_dev(host->mmc),
652 			 "DMA failed: %d, falling back to PIO\n", data->error);
653 		return;
654 	}
655 
656 	/*
657 	 * The datasheet tells us to check a response from the card, whereas
658 	 * responses only come after the command phase, not after the data
659 	 * phase. Let's check anyway.
660 	 */
661 	if (host->irq_status & USDHI6_SD_INFO1_RSP_END)
662 		dev_warn(mmc_dev(host->mmc), "Unexpected response received!\n");
663 }
664 
usdhi6_dma_kick(struct usdhi6_host * host)665 static void usdhi6_dma_kick(struct usdhi6_host *host)
666 {
667 	if (host->mrq->data->flags & MMC_DATA_READ)
668 		dma_async_issue_pending(host->chan_rx);
669 	else
670 		dma_async_issue_pending(host->chan_tx);
671 }
672 
usdhi6_dma_request(struct usdhi6_host * host,phys_addr_t start)673 static void usdhi6_dma_request(struct usdhi6_host *host, phys_addr_t start)
674 {
675 	struct dma_slave_config cfg = {
676 		.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
677 		.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
678 	};
679 	int ret;
680 
681 	host->chan_tx = dma_request_chan(mmc_dev(host->mmc), "tx");
682 	dev_dbg(mmc_dev(host->mmc), "%s: TX: got channel %p\n", __func__,
683 		host->chan_tx);
684 
685 	if (IS_ERR(host->chan_tx)) {
686 		host->chan_tx = NULL;
687 		return;
688 	}
689 
690 	cfg.direction = DMA_MEM_TO_DEV;
691 	cfg.dst_addr = start + USDHI6_SD_BUF0;
692 	cfg.dst_maxburst = 128;	/* 128 words * 4 bytes = 512 bytes */
693 	cfg.src_addr = 0;
694 	ret = dmaengine_slave_config(host->chan_tx, &cfg);
695 	if (ret < 0)
696 		goto e_release_tx;
697 
698 	host->chan_rx = dma_request_chan(mmc_dev(host->mmc), "rx");
699 	dev_dbg(mmc_dev(host->mmc), "%s: RX: got channel %p\n", __func__,
700 		host->chan_rx);
701 
702 	if (IS_ERR(host->chan_rx)) {
703 		host->chan_rx = NULL;
704 		goto e_release_tx;
705 	}
706 
707 	cfg.direction = DMA_DEV_TO_MEM;
708 	cfg.src_addr = cfg.dst_addr;
709 	cfg.src_maxburst = 128;	/* 128 words * 4 bytes = 512 bytes */
710 	cfg.dst_addr = 0;
711 	ret = dmaengine_slave_config(host->chan_rx, &cfg);
712 	if (ret < 0)
713 		goto e_release_rx;
714 
715 	return;
716 
717 e_release_rx:
718 	dma_release_channel(host->chan_rx);
719 	host->chan_rx = NULL;
720 e_release_tx:
721 	dma_release_channel(host->chan_tx);
722 	host->chan_tx = NULL;
723 }
724 
725 /*			API helpers					*/
726 
usdhi6_clk_set(struct usdhi6_host * host,struct mmc_ios * ios)727 static void usdhi6_clk_set(struct usdhi6_host *host, struct mmc_ios *ios)
728 {
729 	unsigned long rate = ios->clock;
730 	u32 val;
731 	unsigned int i;
732 
733 	for (i = 1000; i; i--) {
734 		if (usdhi6_read(host, USDHI6_SD_INFO2) & USDHI6_SD_INFO2_SCLKDIVEN)
735 			break;
736 		usleep_range(10, 100);
737 	}
738 
739 	if (!i) {
740 		dev_err(mmc_dev(host->mmc), "SD bus busy, clock set aborted\n");
741 		return;
742 	}
743 
744 	val = usdhi6_read(host, USDHI6_SD_CLK_CTRL) & ~USDHI6_SD_CLK_CTRL_DIV_MASK;
745 
746 	if (rate) {
747 		unsigned long new_rate;
748 
749 		if (host->imclk <= rate) {
750 			if (ios->timing != MMC_TIMING_UHS_DDR50) {
751 				/* Cannot have 1-to-1 clock in DDR mode */
752 				new_rate = host->imclk;
753 				val |= 0xff;
754 			} else {
755 				new_rate = host->imclk / 2;
756 			}
757 		} else {
758 			unsigned long div =
759 				roundup_pow_of_two(DIV_ROUND_UP(host->imclk, rate));
760 			val |= div >> 2;
761 			new_rate = host->imclk / div;
762 		}
763 
764 		if (host->rate == new_rate)
765 			return;
766 
767 		host->rate = new_rate;
768 
769 		dev_dbg(mmc_dev(host->mmc), "target %lu, div %u, set %lu\n",
770 			rate, (val & 0xff) << 2, new_rate);
771 	}
772 
773 	/*
774 	 * if old or new rate is equal to input rate, have to switch the clock
775 	 * off before changing and on after
776 	 */
777 	if (host->imclk == rate || host->imclk == host->rate || !rate)
778 		usdhi6_write(host, USDHI6_SD_CLK_CTRL,
779 			     val & ~USDHI6_SD_CLK_CTRL_SCLKEN);
780 
781 	if (!rate) {
782 		host->rate = 0;
783 		return;
784 	}
785 
786 	usdhi6_write(host, USDHI6_SD_CLK_CTRL, val);
787 
788 	if (host->imclk == rate || host->imclk == host->rate ||
789 	    !(val & USDHI6_SD_CLK_CTRL_SCLKEN))
790 		usdhi6_write(host, USDHI6_SD_CLK_CTRL,
791 			     val | USDHI6_SD_CLK_CTRL_SCLKEN);
792 }
793 
usdhi6_set_power(struct usdhi6_host * host,struct mmc_ios * ios)794 static void usdhi6_set_power(struct usdhi6_host *host, struct mmc_ios *ios)
795 {
796 	struct mmc_host *mmc = host->mmc;
797 
798 	if (!IS_ERR(mmc->supply.vmmc))
799 		/* Errors ignored... */
800 		mmc_regulator_set_ocr(mmc, mmc->supply.vmmc,
801 				      ios->power_mode ? ios->vdd : 0);
802 }
803 
usdhi6_reset(struct usdhi6_host * host)804 static int usdhi6_reset(struct usdhi6_host *host)
805 {
806 	int i;
807 
808 	usdhi6_write(host, USDHI6_SOFT_RST, USDHI6_SOFT_RST_RESERVED);
809 	cpu_relax();
810 	usdhi6_write(host, USDHI6_SOFT_RST, USDHI6_SOFT_RST_RESERVED | USDHI6_SOFT_RST_RESET);
811 	for (i = 1000; i; i--)
812 		if (usdhi6_read(host, USDHI6_SOFT_RST) & USDHI6_SOFT_RST_RESET)
813 			break;
814 
815 	return i ? 0 : -ETIMEDOUT;
816 }
817 
usdhi6_set_ios(struct mmc_host * mmc,struct mmc_ios * ios)818 static void usdhi6_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
819 {
820 	struct usdhi6_host *host = mmc_priv(mmc);
821 	u32 option, mode;
822 	int ret;
823 
824 	dev_dbg(mmc_dev(mmc), "%uHz, OCR: %u, power %u, bus-width %u, timing %u\n",
825 		ios->clock, ios->vdd, ios->power_mode, ios->bus_width, ios->timing);
826 
827 	switch (ios->power_mode) {
828 	case MMC_POWER_OFF:
829 		usdhi6_set_power(host, ios);
830 		usdhi6_only_cd(host);
831 		break;
832 	case MMC_POWER_UP:
833 		/*
834 		 * We only also touch USDHI6_SD_OPTION from .request(), which
835 		 * cannot race with MMC_POWER_UP
836 		 */
837 		ret = usdhi6_reset(host);
838 		if (ret < 0) {
839 			dev_err(mmc_dev(mmc), "Cannot reset the interface!\n");
840 		} else {
841 			usdhi6_set_power(host, ios);
842 			usdhi6_only_cd(host);
843 		}
844 		break;
845 	case MMC_POWER_ON:
846 		option = usdhi6_read(host, USDHI6_SD_OPTION);
847 		/*
848 		 * The eMMC standard only allows 4 or 8 bits in the DDR mode,
849 		 * the same probably holds for SD cards. We check here anyway,
850 		 * since the datasheet explicitly requires 4 bits for DDR.
851 		 */
852 		if (ios->bus_width == MMC_BUS_WIDTH_1) {
853 			if (ios->timing == MMC_TIMING_UHS_DDR50)
854 				dev_err(mmc_dev(mmc),
855 					"4 bits are required for DDR\n");
856 			option |= USDHI6_SD_OPTION_WIDTH_1;
857 			mode = 0;
858 		} else {
859 			option &= ~USDHI6_SD_OPTION_WIDTH_1;
860 			mode = ios->timing == MMC_TIMING_UHS_DDR50;
861 		}
862 		usdhi6_write(host, USDHI6_SD_OPTION, option);
863 		usdhi6_write(host, USDHI6_SDIF_MODE, mode);
864 		break;
865 	}
866 
867 	if (host->rate != ios->clock)
868 		usdhi6_clk_set(host, ios);
869 }
870 
871 /* This is data timeout. Response timeout is fixed to 640 clock cycles */
usdhi6_timeout_set(struct usdhi6_host * host)872 static void usdhi6_timeout_set(struct usdhi6_host *host)
873 {
874 	struct mmc_request *mrq = host->mrq;
875 	u32 val;
876 	unsigned long ticks;
877 
878 	if (!mrq->data)
879 		ticks = host->rate / 1000 * mrq->cmd->busy_timeout;
880 	else
881 		ticks = host->rate / 1000000 * (mrq->data->timeout_ns / 1000) +
882 			mrq->data->timeout_clks;
883 
884 	if (!ticks || ticks > 1 << 27)
885 		/* Max timeout */
886 		val = 14;
887 	else if (ticks < 1 << 13)
888 		/* Min timeout */
889 		val = 0;
890 	else
891 		val = order_base_2(ticks) - 13;
892 
893 	dev_dbg(mmc_dev(host->mmc), "Set %s timeout %lu ticks @ %lu Hz\n",
894 		mrq->data ? "data" : "cmd", ticks, host->rate);
895 
896 	/* Timeout Counter mask: 0xf0 */
897 	usdhi6_write(host, USDHI6_SD_OPTION, (val << USDHI6_SD_OPTION_TIMEOUT_SHIFT) |
898 		     (usdhi6_read(host, USDHI6_SD_OPTION) & ~USDHI6_SD_OPTION_TIMEOUT_MASK));
899 }
900 
usdhi6_request_done(struct usdhi6_host * host)901 static void usdhi6_request_done(struct usdhi6_host *host)
902 {
903 	struct mmc_request *mrq = host->mrq;
904 	struct mmc_data *data = mrq->data;
905 
906 	if (WARN(host->pg.page || host->head_pg.page,
907 		 "Page %p or %p not unmapped: wait %u, CMD%d(%c) @ +0x%zx %ux%u in SG%u!\n",
908 		 host->pg.page, host->head_pg.page, host->wait, mrq->cmd->opcode,
909 		 data ? (data->flags & MMC_DATA_READ ? 'R' : 'W') : '-',
910 		 data ? host->offset : 0, data ? data->blocks : 0,
911 		 data ? data->blksz : 0, data ? data->sg_len : 0))
912 		usdhi6_sg_unmap(host, true);
913 
914 	if (mrq->cmd->error ||
915 	    (data && data->error) ||
916 	    (mrq->stop && mrq->stop->error))
917 		dev_dbg(mmc_dev(host->mmc), "%s(CMD%d: %ux%u): err %d %d %d\n",
918 			__func__, mrq->cmd->opcode, data ? data->blocks : 0,
919 			data ? data->blksz : 0,
920 			mrq->cmd->error,
921 			data ? data->error : 1,
922 			mrq->stop ? mrq->stop->error : 1);
923 
924 	/* Disable DMA */
925 	usdhi6_write(host, USDHI6_CC_EXT_MODE, 0);
926 	host->wait = USDHI6_WAIT_FOR_REQUEST;
927 	host->mrq = NULL;
928 
929 	mmc_request_done(host->mmc, mrq);
930 }
931 
usdhi6_cmd_flags(struct usdhi6_host * host)932 static int usdhi6_cmd_flags(struct usdhi6_host *host)
933 {
934 	struct mmc_request *mrq = host->mrq;
935 	struct mmc_command *cmd = mrq->cmd;
936 	u16 opc = cmd->opcode;
937 
938 	if (host->app_cmd) {
939 		host->app_cmd = false;
940 		opc |= USDHI6_SD_CMD_APP;
941 	}
942 
943 	if (mrq->data) {
944 		opc |= USDHI6_SD_CMD_DATA;
945 
946 		if (mrq->data->flags & MMC_DATA_READ)
947 			opc |= USDHI6_SD_CMD_READ;
948 
949 		if (cmd->opcode == MMC_READ_MULTIPLE_BLOCK ||
950 		    cmd->opcode == MMC_WRITE_MULTIPLE_BLOCK ||
951 		    (cmd->opcode == SD_IO_RW_EXTENDED &&
952 		     mrq->data->blocks > 1)) {
953 			opc |= USDHI6_SD_CMD_MULTI;
954 			if (!mrq->stop)
955 				opc |= USDHI6_SD_CMD_CMD12_AUTO_OFF;
956 		}
957 
958 		switch (mmc_resp_type(cmd)) {
959 		case MMC_RSP_NONE:
960 			opc |= USDHI6_SD_CMD_MODE_RSP_NONE;
961 			break;
962 		case MMC_RSP_R1:
963 			opc |= USDHI6_SD_CMD_MODE_RSP_R1;
964 			break;
965 		case MMC_RSP_R1B:
966 			opc |= USDHI6_SD_CMD_MODE_RSP_R1B;
967 			break;
968 		case MMC_RSP_R2:
969 			opc |= USDHI6_SD_CMD_MODE_RSP_R2;
970 			break;
971 		case MMC_RSP_R3:
972 			opc |= USDHI6_SD_CMD_MODE_RSP_R3;
973 			break;
974 		default:
975 			dev_warn(mmc_dev(host->mmc),
976 				 "Unknown response type %d\n",
977 				 mmc_resp_type(cmd));
978 			return -EINVAL;
979 		}
980 	}
981 
982 	return opc;
983 }
984 
usdhi6_rq_start(struct usdhi6_host * host)985 static int usdhi6_rq_start(struct usdhi6_host *host)
986 {
987 	struct mmc_request *mrq = host->mrq;
988 	struct mmc_command *cmd = mrq->cmd;
989 	struct mmc_data *data = mrq->data;
990 	int opc = usdhi6_cmd_flags(host);
991 	int i;
992 
993 	if (opc < 0)
994 		return opc;
995 
996 	for (i = 1000; i; i--) {
997 		if (!(usdhi6_read(host, USDHI6_SD_INFO2) & USDHI6_SD_INFO2_CBSY))
998 			break;
999 		usleep_range(10, 100);
1000 	}
1001 
1002 	if (!i) {
1003 		dev_dbg(mmc_dev(host->mmc), "Command active, request aborted\n");
1004 		return -EAGAIN;
1005 	}
1006 
1007 	if (data) {
1008 		bool use_dma;
1009 		int ret = 0;
1010 
1011 		host->page_idx = 0;
1012 
1013 		if (cmd->opcode == SD_IO_RW_EXTENDED && data->blocks > 1) {
1014 			switch (data->blksz) {
1015 			case 512:
1016 				break;
1017 			case 32:
1018 			case 64:
1019 			case 128:
1020 			case 256:
1021 				if (mrq->stop)
1022 					ret = -EINVAL;
1023 				break;
1024 			default:
1025 				ret = -EINVAL;
1026 			}
1027 		} else if ((cmd->opcode == MMC_READ_MULTIPLE_BLOCK ||
1028 			    cmd->opcode == MMC_WRITE_MULTIPLE_BLOCK) &&
1029 			   data->blksz != 512) {
1030 			ret = -EINVAL;
1031 		}
1032 
1033 		if (ret < 0) {
1034 			dev_warn(mmc_dev(host->mmc), "%s(): %u blocks of %u bytes\n",
1035 				 __func__, data->blocks, data->blksz);
1036 			return -EINVAL;
1037 		}
1038 
1039 		if (cmd->opcode == MMC_READ_MULTIPLE_BLOCK ||
1040 		    cmd->opcode == MMC_WRITE_MULTIPLE_BLOCK ||
1041 		    (cmd->opcode == SD_IO_RW_EXTENDED &&
1042 		     data->blocks > 1))
1043 			usdhi6_sg_prep(host);
1044 
1045 		usdhi6_write(host, USDHI6_SD_SIZE, data->blksz);
1046 
1047 		if ((data->blksz >= USDHI6_MIN_DMA ||
1048 		     data->blocks > 1) &&
1049 		    (data->blksz % 4 ||
1050 		     data->sg->offset % 4))
1051 			dev_dbg(mmc_dev(host->mmc),
1052 				"Bad SG of %u: %ux%u @ %u\n", data->sg_len,
1053 				data->blksz, data->blocks, data->sg->offset);
1054 
1055 		/* Enable DMA for USDHI6_MIN_DMA bytes or more */
1056 		use_dma = data->blksz >= USDHI6_MIN_DMA &&
1057 			!(data->blksz % 4) &&
1058 			usdhi6_dma_start(host) >= DMA_MIN_COOKIE;
1059 
1060 		if (use_dma)
1061 			usdhi6_write(host, USDHI6_CC_EXT_MODE, USDHI6_CC_EXT_MODE_SDRW);
1062 
1063 		dev_dbg(mmc_dev(host->mmc),
1064 			"%s(): request opcode %u, %u blocks of %u bytes in %u segments, %s %s @+0x%x%s\n",
1065 			__func__, cmd->opcode, data->blocks, data->blksz,
1066 			data->sg_len, use_dma ? "DMA" : "PIO",
1067 			data->flags & MMC_DATA_READ ? "read" : "write",
1068 			data->sg->offset, mrq->stop ? " + stop" : "");
1069 	} else {
1070 		dev_dbg(mmc_dev(host->mmc), "%s(): request opcode %u\n",
1071 			__func__, cmd->opcode);
1072 	}
1073 
1074 	/* We have to get a command completion interrupt with DMA too */
1075 	usdhi6_wait_for_resp(host);
1076 
1077 	host->wait = USDHI6_WAIT_FOR_CMD;
1078 	schedule_delayed_work(&host->timeout_work, host->timeout);
1079 
1080 	/* SEC bit is required to enable block counting by the core */
1081 	usdhi6_write(host, USDHI6_SD_STOP,
1082 		     data && data->blocks > 1 ? USDHI6_SD_STOP_SEC : 0);
1083 	usdhi6_write(host, USDHI6_SD_ARG, cmd->arg);
1084 
1085 	/* Kick command execution */
1086 	usdhi6_write(host, USDHI6_SD_CMD, opc);
1087 
1088 	return 0;
1089 }
1090 
usdhi6_request(struct mmc_host * mmc,struct mmc_request * mrq)1091 static void usdhi6_request(struct mmc_host *mmc, struct mmc_request *mrq)
1092 {
1093 	struct usdhi6_host *host = mmc_priv(mmc);
1094 	int ret;
1095 
1096 	cancel_delayed_work_sync(&host->timeout_work);
1097 
1098 	host->mrq = mrq;
1099 	host->sg = NULL;
1100 
1101 	usdhi6_timeout_set(host);
1102 	ret = usdhi6_rq_start(host);
1103 	if (ret < 0) {
1104 		mrq->cmd->error = ret;
1105 		usdhi6_request_done(host);
1106 	}
1107 }
1108 
usdhi6_get_cd(struct mmc_host * mmc)1109 static int usdhi6_get_cd(struct mmc_host *mmc)
1110 {
1111 	struct usdhi6_host *host = mmc_priv(mmc);
1112 	/* Read is atomic, no need to lock */
1113 	u32 status = usdhi6_read(host, USDHI6_SD_INFO1) & USDHI6_SD_INFO1_CD;
1114 
1115 /*
1116  *	level	status.CD	CD_ACTIVE_HIGH	card present
1117  *	1	0		0		0
1118  *	1	0		1		1
1119  *	0	1		0		1
1120  *	0	1		1		0
1121  */
1122 	return !status ^ !(mmc->caps2 & MMC_CAP2_CD_ACTIVE_HIGH);
1123 }
1124 
usdhi6_get_ro(struct mmc_host * mmc)1125 static int usdhi6_get_ro(struct mmc_host *mmc)
1126 {
1127 	struct usdhi6_host *host = mmc_priv(mmc);
1128 	/* No locking as above */
1129 	u32 status = usdhi6_read(host, USDHI6_SD_INFO1) & USDHI6_SD_INFO1_WP;
1130 
1131 /*
1132  *	level	status.WP	RO_ACTIVE_HIGH	card read-only
1133  *	1	0		0		0
1134  *	1	0		1		1
1135  *	0	1		0		1
1136  *	0	1		1		0
1137  */
1138 	return !status ^ !(mmc->caps2 & MMC_CAP2_RO_ACTIVE_HIGH);
1139 }
1140 
usdhi6_enable_sdio_irq(struct mmc_host * mmc,int enable)1141 static void usdhi6_enable_sdio_irq(struct mmc_host *mmc, int enable)
1142 {
1143 	struct usdhi6_host *host = mmc_priv(mmc);
1144 
1145 	dev_dbg(mmc_dev(mmc), "%s(): %sable\n", __func__, enable ? "en" : "dis");
1146 
1147 	if (enable) {
1148 		host->sdio_mask = USDHI6_SDIO_INFO1_IRQ & ~USDHI6_SDIO_INFO1_IOIRQ;
1149 		usdhi6_write(host, USDHI6_SDIO_INFO1_MASK, host->sdio_mask);
1150 		usdhi6_write(host, USDHI6_SDIO_MODE, 1);
1151 	} else {
1152 		usdhi6_write(host, USDHI6_SDIO_MODE, 0);
1153 		usdhi6_write(host, USDHI6_SDIO_INFO1_MASK, USDHI6_SDIO_INFO1_IRQ);
1154 		host->sdio_mask = USDHI6_SDIO_INFO1_IRQ;
1155 	}
1156 }
1157 
usdhi6_set_pinstates(struct usdhi6_host * host,int voltage)1158 static int usdhi6_set_pinstates(struct usdhi6_host *host, int voltage)
1159 {
1160 	if (IS_ERR(host->pins_uhs))
1161 		return 0;
1162 
1163 	switch (voltage) {
1164 	case MMC_SIGNAL_VOLTAGE_180:
1165 	case MMC_SIGNAL_VOLTAGE_120:
1166 		return pinctrl_select_state(host->pinctrl,
1167 					    host->pins_uhs);
1168 
1169 	default:
1170 		return pinctrl_select_default_state(mmc_dev(host->mmc));
1171 	}
1172 }
1173 
usdhi6_sig_volt_switch(struct mmc_host * mmc,struct mmc_ios * ios)1174 static int usdhi6_sig_volt_switch(struct mmc_host *mmc, struct mmc_ios *ios)
1175 {
1176 	int ret;
1177 
1178 	ret = mmc_regulator_set_vqmmc(mmc, ios);
1179 	if (ret < 0)
1180 		return ret;
1181 
1182 	ret = usdhi6_set_pinstates(mmc_priv(mmc), ios->signal_voltage);
1183 	if (ret)
1184 		dev_warn_once(mmc_dev(mmc),
1185 			      "Failed to set pinstate err=%d\n", ret);
1186 	return ret;
1187 }
1188 
usdhi6_card_busy(struct mmc_host * mmc)1189 static int usdhi6_card_busy(struct mmc_host *mmc)
1190 {
1191 	struct usdhi6_host *host = mmc_priv(mmc);
1192 	u32 tmp = usdhi6_read(host, USDHI6_SD_INFO2);
1193 
1194 	/* Card is busy if it is pulling dat[0] low */
1195 	return !(tmp & USDHI6_SD_INFO2_SDDAT0);
1196 }
1197 
1198 static const struct mmc_host_ops usdhi6_ops = {
1199 	.request	= usdhi6_request,
1200 	.set_ios	= usdhi6_set_ios,
1201 	.get_cd		= usdhi6_get_cd,
1202 	.get_ro		= usdhi6_get_ro,
1203 	.enable_sdio_irq = usdhi6_enable_sdio_irq,
1204 	.start_signal_voltage_switch = usdhi6_sig_volt_switch,
1205 	.card_busy = usdhi6_card_busy,
1206 };
1207 
1208 /*			State machine handlers				*/
1209 
usdhi6_resp_cmd12(struct usdhi6_host * host)1210 static void usdhi6_resp_cmd12(struct usdhi6_host *host)
1211 {
1212 	struct mmc_command *cmd = host->mrq->stop;
1213 	cmd->resp[0] = usdhi6_read(host, USDHI6_SD_RSP10);
1214 }
1215 
usdhi6_resp_read(struct usdhi6_host * host)1216 static void usdhi6_resp_read(struct usdhi6_host *host)
1217 {
1218 	struct mmc_command *cmd = host->mrq->cmd;
1219 	u32 *rsp = cmd->resp, tmp = 0;
1220 	int i;
1221 
1222 /*
1223  * RSP10	39-8
1224  * RSP32	71-40
1225  * RSP54	103-72
1226  * RSP76	127-104
1227  * R2-type response:
1228  * resp[0]	= r[127..96]
1229  * resp[1]	= r[95..64]
1230  * resp[2]	= r[63..32]
1231  * resp[3]	= r[31..0]
1232  * Other responses:
1233  * resp[0]	= r[39..8]
1234  */
1235 
1236 	if (mmc_resp_type(cmd) == MMC_RSP_NONE)
1237 		return;
1238 
1239 	if (!(host->irq_status & USDHI6_SD_INFO1_RSP_END)) {
1240 		dev_err(mmc_dev(host->mmc),
1241 			"CMD%d: response expected but is missing!\n", cmd->opcode);
1242 		return;
1243 	}
1244 
1245 	if (mmc_resp_type(cmd) & MMC_RSP_136)
1246 		for (i = 0; i < 4; i++) {
1247 			if (i)
1248 				rsp[3 - i] = tmp >> 24;
1249 			tmp = usdhi6_read(host, USDHI6_SD_RSP10 + i * 8);
1250 			rsp[3 - i] |= tmp << 8;
1251 		}
1252 	else if (cmd->opcode == MMC_READ_MULTIPLE_BLOCK ||
1253 		 cmd->opcode == MMC_WRITE_MULTIPLE_BLOCK)
1254 		/* Read RSP54 to avoid conflict with auto CMD12 */
1255 		rsp[0] = usdhi6_read(host, USDHI6_SD_RSP54);
1256 	else
1257 		rsp[0] = usdhi6_read(host, USDHI6_SD_RSP10);
1258 
1259 	dev_dbg(mmc_dev(host->mmc), "Response 0x%x\n", rsp[0]);
1260 }
1261 
usdhi6_blk_read(struct usdhi6_host * host)1262 static int usdhi6_blk_read(struct usdhi6_host *host)
1263 {
1264 	struct mmc_data *data = host->mrq->data;
1265 	u32 *p;
1266 	int i, rest;
1267 
1268 	if (host->io_error) {
1269 		data->error = usdhi6_error_code(host);
1270 		goto error;
1271 	}
1272 
1273 	if (host->pg.page) {
1274 		p = host->blk_page + host->offset;
1275 	} else {
1276 		p = usdhi6_sg_map(host);
1277 		if (!p) {
1278 			data->error = -ENOMEM;
1279 			goto error;
1280 		}
1281 	}
1282 
1283 	for (i = 0; i < data->blksz / 4; i++, p++)
1284 		*p = usdhi6_read(host, USDHI6_SD_BUF0);
1285 
1286 	rest = data->blksz % 4;
1287 	for (i = 0; i < (rest + 1) / 2; i++) {
1288 		u16 d = usdhi6_read16(host, USDHI6_SD_BUF0);
1289 		((u8 *)p)[2 * i] = ((u8 *)&d)[0];
1290 		if (rest > 1 && !i)
1291 			((u8 *)p)[2 * i + 1] = ((u8 *)&d)[1];
1292 	}
1293 
1294 	return 0;
1295 
1296 error:
1297 	dev_dbg(mmc_dev(host->mmc), "%s(): %d\n", __func__, data->error);
1298 	host->wait = USDHI6_WAIT_FOR_REQUEST;
1299 	return data->error;
1300 }
1301 
usdhi6_blk_write(struct usdhi6_host * host)1302 static int usdhi6_blk_write(struct usdhi6_host *host)
1303 {
1304 	struct mmc_data *data = host->mrq->data;
1305 	u32 *p;
1306 	int i, rest;
1307 
1308 	if (host->io_error) {
1309 		data->error = usdhi6_error_code(host);
1310 		goto error;
1311 	}
1312 
1313 	if (host->pg.page) {
1314 		p = host->blk_page + host->offset;
1315 	} else {
1316 		p = usdhi6_sg_map(host);
1317 		if (!p) {
1318 			data->error = -ENOMEM;
1319 			goto error;
1320 		}
1321 	}
1322 
1323 	for (i = 0; i < data->blksz / 4; i++, p++)
1324 		usdhi6_write(host, USDHI6_SD_BUF0, *p);
1325 
1326 	rest = data->blksz % 4;
1327 	for (i = 0; i < (rest + 1) / 2; i++) {
1328 		u16 d;
1329 		((u8 *)&d)[0] = ((u8 *)p)[2 * i];
1330 		if (rest > 1 && !i)
1331 			((u8 *)&d)[1] = ((u8 *)p)[2 * i + 1];
1332 		else
1333 			((u8 *)&d)[1] = 0;
1334 		usdhi6_write16(host, USDHI6_SD_BUF0, d);
1335 	}
1336 
1337 	return 0;
1338 
1339 error:
1340 	dev_dbg(mmc_dev(host->mmc), "%s(): %d\n", __func__, data->error);
1341 	host->wait = USDHI6_WAIT_FOR_REQUEST;
1342 	return data->error;
1343 }
1344 
usdhi6_stop_cmd(struct usdhi6_host * host)1345 static int usdhi6_stop_cmd(struct usdhi6_host *host)
1346 {
1347 	struct mmc_request *mrq = host->mrq;
1348 
1349 	switch (mrq->cmd->opcode) {
1350 	case MMC_READ_MULTIPLE_BLOCK:
1351 	case MMC_WRITE_MULTIPLE_BLOCK:
1352 		if (mrq->stop->opcode == MMC_STOP_TRANSMISSION) {
1353 			host->wait = USDHI6_WAIT_FOR_STOP;
1354 			return 0;
1355 		}
1356 		fallthrough;	/* Unsupported STOP command */
1357 	default:
1358 		dev_err(mmc_dev(host->mmc),
1359 			"unsupported stop CMD%d for CMD%d\n",
1360 			mrq->stop->opcode, mrq->cmd->opcode);
1361 		mrq->stop->error = -EOPNOTSUPP;
1362 	}
1363 
1364 	return -EOPNOTSUPP;
1365 }
1366 
usdhi6_end_cmd(struct usdhi6_host * host)1367 static bool usdhi6_end_cmd(struct usdhi6_host *host)
1368 {
1369 	struct mmc_request *mrq = host->mrq;
1370 	struct mmc_command *cmd = mrq->cmd;
1371 
1372 	if (host->io_error) {
1373 		cmd->error = usdhi6_error_code(host);
1374 		return false;
1375 	}
1376 
1377 	usdhi6_resp_read(host);
1378 
1379 	if (!mrq->data)
1380 		return false;
1381 
1382 	if (host->dma_active) {
1383 		usdhi6_dma_kick(host);
1384 		if (!mrq->stop)
1385 			host->wait = USDHI6_WAIT_FOR_DMA;
1386 		else if (usdhi6_stop_cmd(host) < 0)
1387 			return false;
1388 	} else if (mrq->data->flags & MMC_DATA_READ) {
1389 		if (cmd->opcode == MMC_READ_MULTIPLE_BLOCK ||
1390 		    (cmd->opcode == SD_IO_RW_EXTENDED &&
1391 		     mrq->data->blocks > 1))
1392 			host->wait = USDHI6_WAIT_FOR_MREAD;
1393 		else
1394 			host->wait = USDHI6_WAIT_FOR_READ;
1395 	} else {
1396 		if (cmd->opcode == MMC_WRITE_MULTIPLE_BLOCK ||
1397 		    (cmd->opcode == SD_IO_RW_EXTENDED &&
1398 		     mrq->data->blocks > 1))
1399 			host->wait = USDHI6_WAIT_FOR_MWRITE;
1400 		else
1401 			host->wait = USDHI6_WAIT_FOR_WRITE;
1402 	}
1403 
1404 	return true;
1405 }
1406 
usdhi6_read_block(struct usdhi6_host * host)1407 static bool usdhi6_read_block(struct usdhi6_host *host)
1408 {
1409 	/* ACCESS_END IRQ is already unmasked */
1410 	int ret = usdhi6_blk_read(host);
1411 
1412 	/*
1413 	 * Have to force unmapping both pages: the single block could have been
1414 	 * cross-page, in which case for single-block IO host->page_idx == 0.
1415 	 * So, if we don't force, the second page won't be unmapped.
1416 	 */
1417 	usdhi6_sg_unmap(host, true);
1418 
1419 	if (ret < 0)
1420 		return false;
1421 
1422 	host->wait = USDHI6_WAIT_FOR_DATA_END;
1423 	return true;
1424 }
1425 
usdhi6_mread_block(struct usdhi6_host * host)1426 static bool usdhi6_mread_block(struct usdhi6_host *host)
1427 {
1428 	int ret = usdhi6_blk_read(host);
1429 
1430 	if (ret < 0)
1431 		return false;
1432 
1433 	usdhi6_sg_advance(host);
1434 
1435 	return !host->mrq->data->error &&
1436 		(host->wait != USDHI6_WAIT_FOR_DATA_END || !host->mrq->stop);
1437 }
1438 
usdhi6_write_block(struct usdhi6_host * host)1439 static bool usdhi6_write_block(struct usdhi6_host *host)
1440 {
1441 	int ret = usdhi6_blk_write(host);
1442 
1443 	/* See comment in usdhi6_read_block() */
1444 	usdhi6_sg_unmap(host, true);
1445 
1446 	if (ret < 0)
1447 		return false;
1448 
1449 	host->wait = USDHI6_WAIT_FOR_DATA_END;
1450 	return true;
1451 }
1452 
usdhi6_mwrite_block(struct usdhi6_host * host)1453 static bool usdhi6_mwrite_block(struct usdhi6_host *host)
1454 {
1455 	int ret = usdhi6_blk_write(host);
1456 
1457 	if (ret < 0)
1458 		return false;
1459 
1460 	usdhi6_sg_advance(host);
1461 
1462 	return !host->mrq->data->error &&
1463 		(host->wait != USDHI6_WAIT_FOR_DATA_END || !host->mrq->stop);
1464 }
1465 
1466 /*			Interrupt & timeout handlers			*/
1467 
usdhi6_sd_bh(int irq,void * dev_id)1468 static irqreturn_t usdhi6_sd_bh(int irq, void *dev_id)
1469 {
1470 	struct usdhi6_host *host = dev_id;
1471 	struct mmc_request *mrq;
1472 	struct mmc_command *cmd;
1473 	struct mmc_data *data;
1474 	bool io_wait = false;
1475 
1476 	cancel_delayed_work_sync(&host->timeout_work);
1477 
1478 	mrq = host->mrq;
1479 	if (!mrq)
1480 		return IRQ_HANDLED;
1481 
1482 	cmd = mrq->cmd;
1483 	data = mrq->data;
1484 
1485 	switch (host->wait) {
1486 	case USDHI6_WAIT_FOR_REQUEST:
1487 		/* We're too late, the timeout has already kicked in */
1488 		return IRQ_HANDLED;
1489 	case USDHI6_WAIT_FOR_CMD:
1490 		/* Wait for data? */
1491 		io_wait = usdhi6_end_cmd(host);
1492 		break;
1493 	case USDHI6_WAIT_FOR_MREAD:
1494 		/* Wait for more data? */
1495 		io_wait = usdhi6_mread_block(host);
1496 		break;
1497 	case USDHI6_WAIT_FOR_READ:
1498 		/* Wait for data end? */
1499 		io_wait = usdhi6_read_block(host);
1500 		break;
1501 	case USDHI6_WAIT_FOR_MWRITE:
1502 		/* Wait data to write? */
1503 		io_wait = usdhi6_mwrite_block(host);
1504 		break;
1505 	case USDHI6_WAIT_FOR_WRITE:
1506 		/* Wait for data end? */
1507 		io_wait = usdhi6_write_block(host);
1508 		break;
1509 	case USDHI6_WAIT_FOR_DMA:
1510 		usdhi6_dma_check_error(host);
1511 		break;
1512 	case USDHI6_WAIT_FOR_STOP:
1513 		usdhi6_write(host, USDHI6_SD_STOP, 0);
1514 		if (host->io_error) {
1515 			int ret = usdhi6_error_code(host);
1516 			if (mrq->stop)
1517 				mrq->stop->error = ret;
1518 			else
1519 				mrq->data->error = ret;
1520 			dev_warn(mmc_dev(host->mmc), "%s(): %d\n", __func__, ret);
1521 			break;
1522 		}
1523 		usdhi6_resp_cmd12(host);
1524 		mrq->stop->error = 0;
1525 		break;
1526 	case USDHI6_WAIT_FOR_DATA_END:
1527 		if (host->io_error) {
1528 			mrq->data->error = usdhi6_error_code(host);
1529 			dev_warn(mmc_dev(host->mmc), "%s(): %d\n", __func__,
1530 				 mrq->data->error);
1531 		}
1532 		break;
1533 	default:
1534 		cmd->error = -EFAULT;
1535 		dev_err(mmc_dev(host->mmc), "Invalid state %u\n", host->wait);
1536 		usdhi6_request_done(host);
1537 		return IRQ_HANDLED;
1538 	}
1539 
1540 	if (io_wait) {
1541 		schedule_delayed_work(&host->timeout_work, host->timeout);
1542 		/* Wait for more data or ACCESS_END */
1543 		if (!host->dma_active)
1544 			usdhi6_wait_for_brwe(host, mrq->data->flags & MMC_DATA_READ);
1545 		return IRQ_HANDLED;
1546 	}
1547 
1548 	if (!cmd->error) {
1549 		if (data) {
1550 			if (!data->error) {
1551 				if (host->wait != USDHI6_WAIT_FOR_STOP &&
1552 				    host->mrq->stop &&
1553 				    !host->mrq->stop->error &&
1554 				    !usdhi6_stop_cmd(host)) {
1555 					/* Sending STOP */
1556 					usdhi6_wait_for_resp(host);
1557 
1558 					schedule_delayed_work(&host->timeout_work,
1559 							      host->timeout);
1560 
1561 					return IRQ_HANDLED;
1562 				}
1563 
1564 				data->bytes_xfered = data->blocks * data->blksz;
1565 			} else {
1566 				/* Data error: might need to unmap the last page */
1567 				dev_warn(mmc_dev(host->mmc), "%s(): data error %d\n",
1568 					 __func__, data->error);
1569 				usdhi6_sg_unmap(host, true);
1570 			}
1571 		} else if (cmd->opcode == MMC_APP_CMD) {
1572 			host->app_cmd = true;
1573 		}
1574 	}
1575 
1576 	usdhi6_request_done(host);
1577 
1578 	return IRQ_HANDLED;
1579 }
1580 
usdhi6_sd(int irq,void * dev_id)1581 static irqreturn_t usdhi6_sd(int irq, void *dev_id)
1582 {
1583 	struct usdhi6_host *host = dev_id;
1584 	u16 status, status2, error;
1585 
1586 	status = usdhi6_read(host, USDHI6_SD_INFO1) & ~host->status_mask &
1587 		~USDHI6_SD_INFO1_CARD;
1588 	status2 = usdhi6_read(host, USDHI6_SD_INFO2) & ~host->status2_mask;
1589 
1590 	usdhi6_only_cd(host);
1591 
1592 	dev_dbg(mmc_dev(host->mmc),
1593 		"IRQ status = 0x%08x, status2 = 0x%08x\n", status, status2);
1594 
1595 	if (!status && !status2)
1596 		return IRQ_NONE;
1597 
1598 	error = status2 & USDHI6_SD_INFO2_ERR;
1599 
1600 	/* Ack / clear interrupts */
1601 	if (USDHI6_SD_INFO1_IRQ & status)
1602 		usdhi6_write(host, USDHI6_SD_INFO1,
1603 			     0xffff & ~(USDHI6_SD_INFO1_IRQ & status));
1604 
1605 	if (USDHI6_SD_INFO2_IRQ & status2) {
1606 		if (error)
1607 			/* In error cases BWE and BRE aren't cleared automatically */
1608 			status2 |= USDHI6_SD_INFO2_BWE | USDHI6_SD_INFO2_BRE;
1609 
1610 		usdhi6_write(host, USDHI6_SD_INFO2,
1611 			     0xffff & ~(USDHI6_SD_INFO2_IRQ & status2));
1612 	}
1613 
1614 	host->io_error = error;
1615 	host->irq_status = status;
1616 
1617 	if (error) {
1618 		/* Don't pollute the log with unsupported command timeouts */
1619 		if (host->wait != USDHI6_WAIT_FOR_CMD ||
1620 		    error != USDHI6_SD_INFO2_RSP_TOUT)
1621 			dev_warn(mmc_dev(host->mmc),
1622 				 "%s(): INFO2 error bits 0x%08x\n",
1623 				 __func__, error);
1624 		else
1625 			dev_dbg(mmc_dev(host->mmc),
1626 				"%s(): INFO2 error bits 0x%08x\n",
1627 				__func__, error);
1628 	}
1629 
1630 	return IRQ_WAKE_THREAD;
1631 }
1632 
usdhi6_sdio(int irq,void * dev_id)1633 static irqreturn_t usdhi6_sdio(int irq, void *dev_id)
1634 {
1635 	struct usdhi6_host *host = dev_id;
1636 	u32 status = usdhi6_read(host, USDHI6_SDIO_INFO1) & ~host->sdio_mask;
1637 
1638 	dev_dbg(mmc_dev(host->mmc), "%s(): status 0x%x\n", __func__, status);
1639 
1640 	if (!status)
1641 		return IRQ_NONE;
1642 
1643 	usdhi6_write(host, USDHI6_SDIO_INFO1, ~status);
1644 
1645 	mmc_signal_sdio_irq(host->mmc);
1646 
1647 	return IRQ_HANDLED;
1648 }
1649 
usdhi6_cd(int irq,void * dev_id)1650 static irqreturn_t usdhi6_cd(int irq, void *dev_id)
1651 {
1652 	struct usdhi6_host *host = dev_id;
1653 	struct mmc_host *mmc = host->mmc;
1654 	u16 status;
1655 
1656 	/* We're only interested in hotplug events here */
1657 	status = usdhi6_read(host, USDHI6_SD_INFO1) & ~host->status_mask &
1658 		USDHI6_SD_INFO1_CARD;
1659 
1660 	if (!status)
1661 		return IRQ_NONE;
1662 
1663 	/* Ack */
1664 	usdhi6_write(host, USDHI6_SD_INFO1, ~status);
1665 
1666 	if (!work_pending(&mmc->detect.work) &&
1667 	    (((status & USDHI6_SD_INFO1_CARD_INSERT) &&
1668 	      !mmc->card) ||
1669 	     ((status & USDHI6_SD_INFO1_CARD_EJECT) &&
1670 	      mmc->card)))
1671 		mmc_detect_change(mmc, msecs_to_jiffies(100));
1672 
1673 	return IRQ_HANDLED;
1674 }
1675 
1676 /*
1677  * Actually this should not be needed, if the built-in timeout works reliably in
1678  * the both PIO cases and DMA never fails. But if DMA does fail, a timeout
1679  * handler might be the only way to catch the error.
1680  */
usdhi6_timeout_work(struct work_struct * work)1681 static void usdhi6_timeout_work(struct work_struct *work)
1682 {
1683 	struct delayed_work *d = to_delayed_work(work);
1684 	struct usdhi6_host *host = container_of(d, struct usdhi6_host, timeout_work);
1685 	struct mmc_request *mrq = host->mrq;
1686 	struct mmc_data *data = mrq ? mrq->data : NULL;
1687 	struct scatterlist *sg;
1688 
1689 	dev_warn(mmc_dev(host->mmc),
1690 		 "%s timeout wait %u CMD%d: IRQ 0x%08x:0x%08x, last IRQ 0x%08x\n",
1691 		 host->dma_active ? "DMA" : "PIO",
1692 		 host->wait, mrq ? mrq->cmd->opcode : -1,
1693 		 usdhi6_read(host, USDHI6_SD_INFO1),
1694 		 usdhi6_read(host, USDHI6_SD_INFO2), host->irq_status);
1695 
1696 	if (host->dma_active) {
1697 		usdhi6_dma_kill(host);
1698 		usdhi6_dma_stop_unmap(host);
1699 	}
1700 
1701 	switch (host->wait) {
1702 	default:
1703 		dev_err(mmc_dev(host->mmc), "Invalid state %u\n", host->wait);
1704 		fallthrough;	/* mrq can be NULL, but is impossible */
1705 	case USDHI6_WAIT_FOR_CMD:
1706 		usdhi6_error_code(host);
1707 		if (mrq)
1708 			mrq->cmd->error = -ETIMEDOUT;
1709 		break;
1710 	case USDHI6_WAIT_FOR_STOP:
1711 		usdhi6_error_code(host);
1712 		mrq->stop->error = -ETIMEDOUT;
1713 		break;
1714 	case USDHI6_WAIT_FOR_DMA:
1715 	case USDHI6_WAIT_FOR_MREAD:
1716 	case USDHI6_WAIT_FOR_MWRITE:
1717 	case USDHI6_WAIT_FOR_READ:
1718 	case USDHI6_WAIT_FOR_WRITE:
1719 		sg = host->sg ?: data->sg;
1720 		dev_dbg(mmc_dev(host->mmc),
1721 			"%c: page #%u @ +0x%zx %ux%u in SG%u. Current SG %u bytes @ %u\n",
1722 			data->flags & MMC_DATA_READ ? 'R' : 'W', host->page_idx,
1723 			host->offset, data->blocks, data->blksz, data->sg_len,
1724 			sg_dma_len(sg), sg->offset);
1725 		usdhi6_sg_unmap(host, true);
1726 		fallthrough;	/* page unmapped in USDHI6_WAIT_FOR_DATA_END */
1727 	case USDHI6_WAIT_FOR_DATA_END:
1728 		usdhi6_error_code(host);
1729 		data->error = -ETIMEDOUT;
1730 	}
1731 
1732 	if (mrq)
1733 		usdhi6_request_done(host);
1734 }
1735 
1736 /*			 Probe / release				*/
1737 
1738 static const struct of_device_id usdhi6_of_match[] = {
1739 	{.compatible = "renesas,usdhi6rol0"},
1740 	{}
1741 };
1742 MODULE_DEVICE_TABLE(of, usdhi6_of_match);
1743 
usdhi6_probe(struct platform_device * pdev)1744 static int usdhi6_probe(struct platform_device *pdev)
1745 {
1746 	struct device *dev = &pdev->dev;
1747 	struct mmc_host *mmc;
1748 	struct usdhi6_host *host;
1749 	struct resource *res;
1750 	int irq_cd, irq_sd, irq_sdio;
1751 	u32 version;
1752 	int ret;
1753 
1754 	if (!dev->of_node)
1755 		return -ENODEV;
1756 
1757 	irq_cd = platform_get_irq_byname(pdev, "card detect");
1758 	irq_sd = platform_get_irq_byname(pdev, "data");
1759 	irq_sdio = platform_get_irq_byname(pdev, "SDIO");
1760 	if (irq_sd < 0 || irq_sdio < 0)
1761 		return -ENODEV;
1762 
1763 	mmc = mmc_alloc_host(sizeof(struct usdhi6_host), dev);
1764 	if (!mmc)
1765 		return -ENOMEM;
1766 
1767 	ret = mmc_regulator_get_supply(mmc);
1768 	if (ret)
1769 		goto e_free_mmc;
1770 
1771 	ret = mmc_of_parse(mmc);
1772 	if (ret < 0)
1773 		goto e_free_mmc;
1774 
1775 	host		= mmc_priv(mmc);
1776 	host->mmc	= mmc;
1777 	host->wait	= USDHI6_WAIT_FOR_REQUEST;
1778 	host->timeout	= msecs_to_jiffies(USDHI6_REQ_TIMEOUT_MS);
1779 	/*
1780 	 * We use a fixed timeout of 4s, hence inform the core about it. A
1781 	 * future improvement should instead respect the cmd->busy_timeout.
1782 	 */
1783 	mmc->max_busy_timeout = USDHI6_REQ_TIMEOUT_MS;
1784 
1785 	host->pinctrl = devm_pinctrl_get(&pdev->dev);
1786 	if (IS_ERR(host->pinctrl)) {
1787 		ret = PTR_ERR(host->pinctrl);
1788 		goto e_free_mmc;
1789 	}
1790 
1791 	host->pins_uhs = pinctrl_lookup_state(host->pinctrl, "state_uhs");
1792 
1793 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1794 	host->base = devm_ioremap_resource(dev, res);
1795 	if (IS_ERR(host->base)) {
1796 		ret = PTR_ERR(host->base);
1797 		goto e_free_mmc;
1798 	}
1799 
1800 	host->clk = devm_clk_get(dev, NULL);
1801 	if (IS_ERR(host->clk)) {
1802 		ret = PTR_ERR(host->clk);
1803 		goto e_free_mmc;
1804 	}
1805 
1806 	host->imclk = clk_get_rate(host->clk);
1807 
1808 	ret = clk_prepare_enable(host->clk);
1809 	if (ret < 0)
1810 		goto e_free_mmc;
1811 
1812 	version = usdhi6_read(host, USDHI6_VERSION);
1813 	if ((version & 0xfff) != 0xa0d) {
1814 		ret = -EPERM;
1815 		dev_err(dev, "Version not recognized %x\n", version);
1816 		goto e_clk_off;
1817 	}
1818 
1819 	dev_info(dev, "A USDHI6ROL0 SD host detected with %d ports\n",
1820 		 usdhi6_read(host, USDHI6_SD_PORT_SEL) >> USDHI6_SD_PORT_SEL_PORTS_SHIFT);
1821 
1822 	usdhi6_mask_all(host);
1823 
1824 	if (irq_cd >= 0) {
1825 		ret = devm_request_irq(dev, irq_cd, usdhi6_cd, 0,
1826 				       dev_name(dev), host);
1827 		if (ret < 0)
1828 			goto e_clk_off;
1829 	} else {
1830 		mmc->caps |= MMC_CAP_NEEDS_POLL;
1831 	}
1832 
1833 	ret = devm_request_threaded_irq(dev, irq_sd, usdhi6_sd, usdhi6_sd_bh, 0,
1834 			       dev_name(dev), host);
1835 	if (ret < 0)
1836 		goto e_clk_off;
1837 
1838 	ret = devm_request_irq(dev, irq_sdio, usdhi6_sdio, 0,
1839 			       dev_name(dev), host);
1840 	if (ret < 0)
1841 		goto e_clk_off;
1842 
1843 	INIT_DELAYED_WORK(&host->timeout_work, usdhi6_timeout_work);
1844 
1845 	usdhi6_dma_request(host, res->start);
1846 
1847 	mmc->ops = &usdhi6_ops;
1848 	mmc->caps |= MMC_CAP_SD_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED |
1849 		     MMC_CAP_SDIO_IRQ;
1850 	/* Set .max_segs to some random number. Feel free to adjust. */
1851 	mmc->max_segs = 32;
1852 	mmc->max_blk_size = 512;
1853 	mmc->max_req_size = PAGE_SIZE * mmc->max_segs;
1854 	mmc->max_blk_count = mmc->max_req_size / mmc->max_blk_size;
1855 	/*
1856 	 * Setting .max_seg_size to 1 page would simplify our page-mapping code,
1857 	 * But OTOH, having large segments makes DMA more efficient. We could
1858 	 * check, whether we managed to get DMA and fall back to 1 page
1859 	 * segments, but if we do manage to obtain DMA and then it fails at
1860 	 * run-time and we fall back to PIO, we will continue getting large
1861 	 * segments. So, we wouldn't be able to get rid of the code anyway.
1862 	 */
1863 	mmc->max_seg_size = mmc->max_req_size;
1864 	if (!mmc->f_max)
1865 		mmc->f_max = host->imclk;
1866 	mmc->f_min = host->imclk / 512;
1867 
1868 	platform_set_drvdata(pdev, host);
1869 
1870 	ret = mmc_add_host(mmc);
1871 	if (ret < 0)
1872 		goto e_release_dma;
1873 
1874 	return 0;
1875 
1876 e_release_dma:
1877 	usdhi6_dma_release(host);
1878 e_clk_off:
1879 	clk_disable_unprepare(host->clk);
1880 e_free_mmc:
1881 	mmc_free_host(mmc);
1882 
1883 	return ret;
1884 }
1885 
usdhi6_remove(struct platform_device * pdev)1886 static int usdhi6_remove(struct platform_device *pdev)
1887 {
1888 	struct usdhi6_host *host = platform_get_drvdata(pdev);
1889 
1890 	mmc_remove_host(host->mmc);
1891 
1892 	usdhi6_mask_all(host);
1893 	cancel_delayed_work_sync(&host->timeout_work);
1894 	usdhi6_dma_release(host);
1895 	clk_disable_unprepare(host->clk);
1896 	mmc_free_host(host->mmc);
1897 
1898 	return 0;
1899 }
1900 
1901 static struct platform_driver usdhi6_driver = {
1902 	.probe		= usdhi6_probe,
1903 	.remove		= usdhi6_remove,
1904 	.driver		= {
1905 		.name	= "usdhi6rol0",
1906 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
1907 		.of_match_table = usdhi6_of_match,
1908 	},
1909 };
1910 
1911 module_platform_driver(usdhi6_driver);
1912 
1913 MODULE_DESCRIPTION("Renesas usdhi6rol0 SD/SDIO host driver");
1914 MODULE_LICENSE("GPL v2");
1915 MODULE_ALIAS("platform:usdhi6rol0");
1916 MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>");
1917