xref: /linux/drivers/mmc/host/mmci_stm32_sdmmc.c (revision 4b132aacb0768ac1e652cf517097ea6f237214b9)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) STMicroelectronics 2018 - All Rights Reserved
4  * Author: Ludovic.barre@st.com for STMicroelectronics.
5  */
6 #include <linux/bitfield.h>
7 #include <linux/delay.h>
8 #include <linux/dma-mapping.h>
9 #include <linux/iopoll.h>
10 #include <linux/mmc/host.h>
11 #include <linux/mmc/card.h>
12 #include <linux/of_address.h>
13 #include <linux/reset.h>
14 #include <linux/scatterlist.h>
15 #include "mmci.h"
16 
17 #define SDMMC_LLI_BUF_LEN	PAGE_SIZE
18 
19 #define DLYB_CR			0x0
20 #define DLYB_CR_DEN		BIT(0)
21 #define DLYB_CR_SEN		BIT(1)
22 
23 #define DLYB_CFGR		0x4
24 #define DLYB_CFGR_SEL_MASK	GENMASK(3, 0)
25 #define DLYB_CFGR_UNIT_MASK	GENMASK(14, 8)
26 #define DLYB_CFGR_LNG_MASK	GENMASK(27, 16)
27 #define DLYB_CFGR_LNGF		BIT(31)
28 
29 #define DLYB_NB_DELAY		11
30 #define DLYB_CFGR_SEL_MAX	(DLYB_NB_DELAY + 1)
31 #define DLYB_CFGR_UNIT_MAX	127
32 
33 #define DLYB_LNG_TIMEOUT_US	1000
34 #define SDMMC_VSWEND_TIMEOUT_US 10000
35 
36 #define SYSCFG_DLYBSD_CR	0x0
37 #define DLYBSD_CR_EN		BIT(0)
38 #define DLYBSD_CR_RXTAPSEL_MASK	GENMASK(6, 1)
39 #define DLYBSD_TAPSEL_NB	32
40 #define DLYBSD_BYP_EN		BIT(16)
41 #define DLYBSD_BYP_CMD		GENMASK(21, 17)
42 #define DLYBSD_ANTIGLITCH_EN	BIT(22)
43 
44 #define SYSCFG_DLYBSD_SR	0x4
45 #define DLYBSD_SR_LOCK		BIT(0)
46 #define DLYBSD_SR_RXTAPSEL_ACK	BIT(1)
47 
48 #define DLYBSD_TIMEOUT_1S_IN_US	1000000
49 
50 struct sdmmc_lli_desc {
51 	u32 idmalar;
52 	u32 idmabase;
53 	u32 idmasize;
54 };
55 
56 struct sdmmc_idma {
57 	dma_addr_t sg_dma;
58 	void *sg_cpu;
59 	dma_addr_t bounce_dma_addr;
60 	void *bounce_buf;
61 	bool use_bounce_buffer;
62 };
63 
64 struct sdmmc_dlyb;
65 
66 struct sdmmc_tuning_ops {
67 	int (*dlyb_enable)(struct sdmmc_dlyb *dlyb);
68 	void (*set_input_ck)(struct sdmmc_dlyb *dlyb);
69 	int (*tuning_prepare)(struct mmci_host *host);
70 	int (*set_cfg)(struct sdmmc_dlyb *dlyb, int unit __maybe_unused,
71 		       int phase, bool sampler __maybe_unused);
72 };
73 
74 struct sdmmc_dlyb {
75 	void __iomem *base;
76 	u32 unit;
77 	u32 max;
78 	struct sdmmc_tuning_ops *ops;
79 };
80 
81 static int sdmmc_idma_validate_data(struct mmci_host *host,
82 				    struct mmc_data *data)
83 {
84 	struct sdmmc_idma *idma = host->dma_priv;
85 	struct device *dev = mmc_dev(host->mmc);
86 	struct scatterlist *sg;
87 	int i;
88 
89 	/*
90 	 * idma has constraints on idmabase & idmasize for each element
91 	 * excepted the last element which has no constraint on idmasize
92 	 */
93 	idma->use_bounce_buffer = false;
94 	for_each_sg(data->sg, sg, data->sg_len - 1, i) {
95 		if (!IS_ALIGNED(sg->offset, sizeof(u32)) ||
96 		    !IS_ALIGNED(sg->length,
97 				host->variant->stm32_idmabsize_align)) {
98 			dev_dbg(mmc_dev(host->mmc),
99 				"unaligned scatterlist: ofst:%x length:%d\n",
100 				data->sg->offset, data->sg->length);
101 			goto use_bounce_buffer;
102 		}
103 	}
104 
105 	if (!IS_ALIGNED(sg->offset, sizeof(u32))) {
106 		dev_dbg(mmc_dev(host->mmc),
107 			"unaligned last scatterlist: ofst:%x length:%d\n",
108 			data->sg->offset, data->sg->length);
109 		goto use_bounce_buffer;
110 	}
111 
112 	return 0;
113 
114 use_bounce_buffer:
115 	if (!idma->bounce_buf) {
116 		idma->bounce_buf = dmam_alloc_coherent(dev,
117 						       host->mmc->max_req_size,
118 						       &idma->bounce_dma_addr,
119 						       GFP_KERNEL);
120 		if (!idma->bounce_buf) {
121 			dev_err(dev, "Unable to map allocate DMA bounce buffer.\n");
122 			return -ENOMEM;
123 		}
124 	}
125 
126 	idma->use_bounce_buffer = true;
127 
128 	return 0;
129 }
130 
131 static int _sdmmc_idma_prep_data(struct mmci_host *host,
132 				 struct mmc_data *data)
133 {
134 	struct sdmmc_idma *idma = host->dma_priv;
135 
136 	if (idma->use_bounce_buffer) {
137 		if (data->flags & MMC_DATA_WRITE) {
138 			unsigned int xfer_bytes = data->blksz * data->blocks;
139 
140 			sg_copy_to_buffer(data->sg, data->sg_len,
141 					  idma->bounce_buf, xfer_bytes);
142 			dma_wmb();
143 		}
144 	} else {
145 		int n_elem;
146 
147 		n_elem = dma_map_sg(mmc_dev(host->mmc),
148 				    data->sg,
149 				    data->sg_len,
150 				    mmc_get_dma_dir(data));
151 
152 		if (!n_elem) {
153 			dev_err(mmc_dev(host->mmc), "dma_map_sg failed\n");
154 			return -EINVAL;
155 		}
156 	}
157 	return 0;
158 }
159 
160 static int sdmmc_idma_prep_data(struct mmci_host *host,
161 				struct mmc_data *data, bool next)
162 {
163 	/* Check if job is already prepared. */
164 	if (!next && data->host_cookie == host->next_cookie)
165 		return 0;
166 
167 	return _sdmmc_idma_prep_data(host, data);
168 }
169 
170 static void sdmmc_idma_unprep_data(struct mmci_host *host,
171 				   struct mmc_data *data, int err)
172 {
173 	struct sdmmc_idma *idma = host->dma_priv;
174 
175 	if (idma->use_bounce_buffer) {
176 		if (data->flags & MMC_DATA_READ) {
177 			unsigned int xfer_bytes = data->blksz * data->blocks;
178 
179 			sg_copy_from_buffer(data->sg, data->sg_len,
180 					    idma->bounce_buf, xfer_bytes);
181 		}
182 	} else {
183 		dma_unmap_sg(mmc_dev(host->mmc), data->sg, data->sg_len,
184 			     mmc_get_dma_dir(data));
185 	}
186 }
187 
188 static int sdmmc_idma_setup(struct mmci_host *host)
189 {
190 	struct sdmmc_idma *idma;
191 	struct device *dev = mmc_dev(host->mmc);
192 
193 	idma = devm_kzalloc(dev, sizeof(*idma), GFP_KERNEL);
194 	if (!idma)
195 		return -ENOMEM;
196 
197 	host->dma_priv = idma;
198 
199 	if (host->variant->dma_lli) {
200 		idma->sg_cpu = dmam_alloc_coherent(dev, SDMMC_LLI_BUF_LEN,
201 						   &idma->sg_dma, GFP_KERNEL);
202 		if (!idma->sg_cpu) {
203 			dev_err(dev, "Failed to alloc IDMA descriptor\n");
204 			return -ENOMEM;
205 		}
206 		host->mmc->max_segs = SDMMC_LLI_BUF_LEN /
207 			sizeof(struct sdmmc_lli_desc);
208 		host->mmc->max_seg_size = host->variant->stm32_idmabsize_mask;
209 
210 		host->mmc->max_req_size = SZ_1M;
211 	} else {
212 		host->mmc->max_segs = 1;
213 		host->mmc->max_seg_size = host->mmc->max_req_size;
214 	}
215 
216 	return dma_set_max_seg_size(dev, host->mmc->max_seg_size);
217 }
218 
219 static int sdmmc_idma_start(struct mmci_host *host, unsigned int *datactrl)
220 
221 {
222 	struct sdmmc_idma *idma = host->dma_priv;
223 	struct sdmmc_lli_desc *desc = (struct sdmmc_lli_desc *)idma->sg_cpu;
224 	struct mmc_data *data = host->data;
225 	struct scatterlist *sg;
226 	int i;
227 
228 	host->dma_in_progress = true;
229 
230 	if (!host->variant->dma_lli || data->sg_len == 1 ||
231 	    idma->use_bounce_buffer) {
232 		u32 dma_addr;
233 
234 		if (idma->use_bounce_buffer)
235 			dma_addr = idma->bounce_dma_addr;
236 		else
237 			dma_addr = sg_dma_address(data->sg);
238 
239 		writel_relaxed(dma_addr,
240 			       host->base + MMCI_STM32_IDMABASE0R);
241 		writel_relaxed(MMCI_STM32_IDMAEN,
242 			       host->base + MMCI_STM32_IDMACTRLR);
243 		return 0;
244 	}
245 
246 	for_each_sg(data->sg, sg, data->sg_len, i) {
247 		desc[i].idmalar = (i + 1) * sizeof(struct sdmmc_lli_desc);
248 		desc[i].idmalar |= MMCI_STM32_ULA | MMCI_STM32_ULS
249 			| MMCI_STM32_ABR;
250 		desc[i].idmabase = sg_dma_address(sg);
251 		desc[i].idmasize = sg_dma_len(sg);
252 	}
253 
254 	/* notice the end of link list */
255 	desc[data->sg_len - 1].idmalar &= ~MMCI_STM32_ULA;
256 
257 	dma_wmb();
258 	writel_relaxed(idma->sg_dma, host->base + MMCI_STM32_IDMABAR);
259 	writel_relaxed(desc[0].idmalar, host->base + MMCI_STM32_IDMALAR);
260 	writel_relaxed(desc[0].idmabase, host->base + MMCI_STM32_IDMABASE0R);
261 	writel_relaxed(desc[0].idmasize, host->base + MMCI_STM32_IDMABSIZER);
262 	writel_relaxed(MMCI_STM32_IDMAEN | MMCI_STM32_IDMALLIEN,
263 		       host->base + MMCI_STM32_IDMACTRLR);
264 
265 	return 0;
266 }
267 
268 static void sdmmc_idma_error(struct mmci_host *host)
269 {
270 	struct mmc_data *data = host->data;
271 	struct sdmmc_idma *idma = host->dma_priv;
272 
273 	if (!dma_inprogress(host))
274 		return;
275 
276 	writel_relaxed(0, host->base + MMCI_STM32_IDMACTRLR);
277 	host->dma_in_progress = false;
278 	data->host_cookie = 0;
279 
280 	if (!idma->use_bounce_buffer)
281 		dma_unmap_sg(mmc_dev(host->mmc), data->sg, data->sg_len,
282 			     mmc_get_dma_dir(data));
283 }
284 
285 static void sdmmc_idma_finalize(struct mmci_host *host, struct mmc_data *data)
286 {
287 	if (!dma_inprogress(host))
288 		return;
289 
290 	writel_relaxed(0, host->base + MMCI_STM32_IDMACTRLR);
291 	host->dma_in_progress = false;
292 
293 	if (!data->host_cookie)
294 		sdmmc_idma_unprep_data(host, data, 0);
295 }
296 
297 static void mmci_sdmmc_set_clkreg(struct mmci_host *host, unsigned int desired)
298 {
299 	unsigned int clk = 0, ddr = 0;
300 
301 	if (host->mmc->ios.timing == MMC_TIMING_MMC_DDR52 ||
302 	    host->mmc->ios.timing == MMC_TIMING_UHS_DDR50)
303 		ddr = MCI_STM32_CLK_DDR;
304 
305 	/*
306 	 * cclk = mclk / (2 * clkdiv)
307 	 * clkdiv 0 => bypass
308 	 * in ddr mode bypass is not possible
309 	 */
310 	if (desired) {
311 		if (desired >= host->mclk && !ddr) {
312 			host->cclk = host->mclk;
313 		} else {
314 			clk = DIV_ROUND_UP(host->mclk, 2 * desired);
315 			if (clk > MCI_STM32_CLK_CLKDIV_MSK)
316 				clk = MCI_STM32_CLK_CLKDIV_MSK;
317 			host->cclk = host->mclk / (2 * clk);
318 		}
319 	} else {
320 		/*
321 		 * while power-on phase the clock can't be define to 0,
322 		 * Only power-off and power-cyc deactivate the clock.
323 		 * if desired clock is 0, set max divider
324 		 */
325 		clk = MCI_STM32_CLK_CLKDIV_MSK;
326 		host->cclk = host->mclk / (2 * clk);
327 	}
328 
329 	/* Set actual clock for debug */
330 	if (host->mmc->ios.power_mode == MMC_POWER_ON)
331 		host->mmc->actual_clock = host->cclk;
332 	else
333 		host->mmc->actual_clock = 0;
334 
335 	if (host->mmc->ios.bus_width == MMC_BUS_WIDTH_4)
336 		clk |= MCI_STM32_CLK_WIDEBUS_4;
337 	if (host->mmc->ios.bus_width == MMC_BUS_WIDTH_8)
338 		clk |= MCI_STM32_CLK_WIDEBUS_8;
339 
340 	clk |= MCI_STM32_CLK_HWFCEN;
341 	clk |= host->clk_reg_add;
342 	clk |= ddr;
343 
344 	if (host->mmc->ios.timing >= MMC_TIMING_UHS_SDR50)
345 		clk |= MCI_STM32_CLK_BUSSPEED;
346 
347 	mmci_write_clkreg(host, clk);
348 }
349 
350 static void sdmmc_dlyb_mp15_input_ck(struct sdmmc_dlyb *dlyb)
351 {
352 	if (!dlyb || !dlyb->base)
353 		return;
354 
355 	/* Output clock = Input clock */
356 	writel_relaxed(0, dlyb->base + DLYB_CR);
357 }
358 
359 static void mmci_sdmmc_set_pwrreg(struct mmci_host *host, unsigned int pwr)
360 {
361 	struct mmc_ios ios = host->mmc->ios;
362 	struct sdmmc_dlyb *dlyb = host->variant_priv;
363 
364 	/* adds OF options */
365 	pwr = host->pwr_reg_add;
366 
367 	if (dlyb && dlyb->ops->set_input_ck)
368 		dlyb->ops->set_input_ck(dlyb);
369 
370 	if (ios.power_mode == MMC_POWER_OFF) {
371 		/* Only a reset could power-off sdmmc */
372 		reset_control_assert(host->rst);
373 		udelay(2);
374 		reset_control_deassert(host->rst);
375 
376 		/*
377 		 * Set the SDMMC in Power-cycle state.
378 		 * This will make that the SDMMC_D[7:0], SDMMC_CMD and SDMMC_CK
379 		 * are driven low, to prevent the Card from being supplied
380 		 * through the signal lines.
381 		 */
382 		mmci_write_pwrreg(host, MCI_STM32_PWR_CYC | pwr);
383 	} else if (ios.power_mode == MMC_POWER_ON) {
384 		/*
385 		 * After power-off (reset): the irq mask defined in probe
386 		 * functionis lost
387 		 * ault irq mask (probe) must be activated
388 		 */
389 		writel(MCI_IRQENABLE | host->variant->start_err,
390 		       host->base + MMCIMASK0);
391 
392 		/* preserves voltage switch bits */
393 		pwr |= host->pwr_reg & (MCI_STM32_VSWITCHEN |
394 					MCI_STM32_VSWITCH);
395 
396 		/*
397 		 * After a power-cycle state, we must set the SDMMC in
398 		 * Power-off. The SDMMC_D[7:0], SDMMC_CMD and SDMMC_CK are
399 		 * driven high. Then we can set the SDMMC to Power-on state
400 		 */
401 		mmci_write_pwrreg(host, MCI_PWR_OFF | pwr);
402 		mdelay(1);
403 		mmci_write_pwrreg(host, MCI_PWR_ON | pwr);
404 	}
405 }
406 
407 static u32 sdmmc_get_dctrl_cfg(struct mmci_host *host)
408 {
409 	u32 datactrl;
410 
411 	datactrl = mmci_dctrl_blksz(host);
412 
413 	if (host->hw_revision >= 3) {
414 		u32 thr = 0;
415 
416 		if (host->mmc->ios.timing == MMC_TIMING_UHS_SDR104 ||
417 		    host->mmc->ios.timing == MMC_TIMING_MMC_HS200) {
418 			thr = ffs(min_t(unsigned int, host->data->blksz,
419 					host->variant->fifosize));
420 			thr = min_t(u32, thr, MMCI_STM32_THR_MASK);
421 		}
422 
423 		writel_relaxed(thr, host->base + MMCI_STM32_FIFOTHRR);
424 	}
425 
426 	if (host->mmc->card && mmc_card_sdio(host->mmc->card) &&
427 	    host->data->blocks == 1)
428 		datactrl |= MCI_DPSM_STM32_MODE_SDIO;
429 	else if (host->data->stop && !host->mrq->sbc)
430 		datactrl |= MCI_DPSM_STM32_MODE_BLOCK_STOP;
431 	else
432 		datactrl |= MCI_DPSM_STM32_MODE_BLOCK;
433 
434 	return datactrl;
435 }
436 
437 static bool sdmmc_busy_complete(struct mmci_host *host, struct mmc_command *cmd,
438 				u32 status, u32 err_msk)
439 {
440 	void __iomem *base = host->base;
441 	u32 busy_d0, busy_d0end, mask, sdmmc_status;
442 
443 	mask = readl_relaxed(base + MMCIMASK0);
444 	sdmmc_status = readl_relaxed(base + MMCISTATUS);
445 	busy_d0end = sdmmc_status & MCI_STM32_BUSYD0END;
446 	busy_d0 = sdmmc_status & MCI_STM32_BUSYD0;
447 
448 	/* complete if there is an error or busy_d0end */
449 	if ((status & err_msk) || busy_d0end)
450 		goto complete;
451 
452 	/*
453 	 * On response the busy signaling is reflected in the BUSYD0 flag.
454 	 * if busy_d0 is in-progress we must activate busyd0end interrupt
455 	 * to wait this completion. Else this request has no busy step.
456 	 */
457 	if (busy_d0) {
458 		if (!host->busy_status) {
459 			writel_relaxed(mask | host->variant->busy_detect_mask,
460 				       base + MMCIMASK0);
461 			host->busy_status = status &
462 				(MCI_CMDSENT | MCI_CMDRESPEND);
463 		}
464 		return false;
465 	}
466 
467 complete:
468 	if (host->busy_status) {
469 		writel_relaxed(mask & ~host->variant->busy_detect_mask,
470 			       base + MMCIMASK0);
471 		host->busy_status = 0;
472 	}
473 
474 	writel_relaxed(host->variant->busy_detect_mask, base + MMCICLEAR);
475 
476 	return true;
477 }
478 
479 static int sdmmc_dlyb_mp15_enable(struct sdmmc_dlyb *dlyb)
480 {
481 	writel_relaxed(DLYB_CR_DEN, dlyb->base + DLYB_CR);
482 
483 	return 0;
484 }
485 
486 static int sdmmc_dlyb_mp15_set_cfg(struct sdmmc_dlyb *dlyb,
487 				   int unit, int phase, bool sampler)
488 {
489 	u32 cfgr;
490 
491 	writel_relaxed(DLYB_CR_SEN | DLYB_CR_DEN, dlyb->base + DLYB_CR);
492 
493 	cfgr = FIELD_PREP(DLYB_CFGR_UNIT_MASK, unit) |
494 	       FIELD_PREP(DLYB_CFGR_SEL_MASK, phase);
495 	writel_relaxed(cfgr, dlyb->base + DLYB_CFGR);
496 
497 	if (!sampler)
498 		writel_relaxed(DLYB_CR_DEN, dlyb->base + DLYB_CR);
499 
500 	return 0;
501 }
502 
503 static int sdmmc_dlyb_mp15_prepare(struct mmci_host *host)
504 {
505 	struct sdmmc_dlyb *dlyb = host->variant_priv;
506 	u32 cfgr;
507 	int i, lng, ret;
508 
509 	for (i = 0; i <= DLYB_CFGR_UNIT_MAX; i++) {
510 		dlyb->ops->set_cfg(dlyb, i, DLYB_CFGR_SEL_MAX, true);
511 
512 		ret = readl_relaxed_poll_timeout(dlyb->base + DLYB_CFGR, cfgr,
513 						 (cfgr & DLYB_CFGR_LNGF),
514 						 1, DLYB_LNG_TIMEOUT_US);
515 		if (ret) {
516 			dev_warn(mmc_dev(host->mmc),
517 				 "delay line cfg timeout unit:%d cfgr:%d\n",
518 				 i, cfgr);
519 			continue;
520 		}
521 
522 		lng = FIELD_GET(DLYB_CFGR_LNG_MASK, cfgr);
523 		if (lng < BIT(DLYB_NB_DELAY) && lng > 0)
524 			break;
525 	}
526 
527 	if (i > DLYB_CFGR_UNIT_MAX)
528 		return -EINVAL;
529 
530 	dlyb->unit = i;
531 	dlyb->max = __fls(lng);
532 
533 	return 0;
534 }
535 
536 static int sdmmc_dlyb_mp25_enable(struct sdmmc_dlyb *dlyb)
537 {
538 	u32 cr, sr;
539 
540 	cr = readl_relaxed(dlyb->base + SYSCFG_DLYBSD_CR);
541 	cr |= DLYBSD_CR_EN;
542 
543 	writel_relaxed(cr, dlyb->base + SYSCFG_DLYBSD_CR);
544 
545 	return readl_relaxed_poll_timeout(dlyb->base + SYSCFG_DLYBSD_SR,
546 					   sr, sr & DLYBSD_SR_LOCK, 1,
547 					   DLYBSD_TIMEOUT_1S_IN_US);
548 }
549 
550 static int sdmmc_dlyb_mp25_set_cfg(struct sdmmc_dlyb *dlyb,
551 				   int unit __maybe_unused, int phase,
552 				   bool sampler __maybe_unused)
553 {
554 	u32 cr, sr;
555 
556 	cr = readl_relaxed(dlyb->base + SYSCFG_DLYBSD_CR);
557 	cr &= ~DLYBSD_CR_RXTAPSEL_MASK;
558 	cr |= FIELD_PREP(DLYBSD_CR_RXTAPSEL_MASK, phase);
559 
560 	writel_relaxed(cr, dlyb->base + SYSCFG_DLYBSD_CR);
561 
562 	return readl_relaxed_poll_timeout(dlyb->base + SYSCFG_DLYBSD_SR,
563 					  sr, sr & DLYBSD_SR_RXTAPSEL_ACK, 1,
564 					  DLYBSD_TIMEOUT_1S_IN_US);
565 }
566 
567 static int sdmmc_dlyb_mp25_prepare(struct mmci_host *host)
568 {
569 	struct sdmmc_dlyb *dlyb = host->variant_priv;
570 
571 	dlyb->max = DLYBSD_TAPSEL_NB;
572 
573 	return 0;
574 }
575 
576 static int sdmmc_dlyb_phase_tuning(struct mmci_host *host, u32 opcode)
577 {
578 	struct sdmmc_dlyb *dlyb = host->variant_priv;
579 	int cur_len = 0, max_len = 0, end_of_len = 0;
580 	int phase, ret;
581 
582 	for (phase = 0; phase <= dlyb->max; phase++) {
583 		ret = dlyb->ops->set_cfg(dlyb, dlyb->unit, phase, false);
584 		if (ret) {
585 			dev_err(mmc_dev(host->mmc), "tuning config failed\n");
586 			return ret;
587 		}
588 
589 		if (mmc_send_tuning(host->mmc, opcode, NULL)) {
590 			cur_len = 0;
591 		} else {
592 			cur_len++;
593 			if (cur_len > max_len) {
594 				max_len = cur_len;
595 				end_of_len = phase;
596 			}
597 		}
598 	}
599 
600 	if (!max_len) {
601 		dev_err(mmc_dev(host->mmc), "no tuning point found\n");
602 		return -EINVAL;
603 	}
604 
605 	if (dlyb->ops->set_input_ck)
606 		dlyb->ops->set_input_ck(dlyb);
607 
608 	phase = end_of_len - max_len / 2;
609 	ret = dlyb->ops->set_cfg(dlyb, dlyb->unit, phase, false);
610 	if (ret) {
611 		dev_err(mmc_dev(host->mmc), "tuning reconfig failed\n");
612 		return ret;
613 	}
614 
615 	dev_dbg(mmc_dev(host->mmc), "unit:%d max_dly:%d phase:%d\n",
616 		dlyb->unit, dlyb->max, phase);
617 
618 	return 0;
619 }
620 
621 static int sdmmc_execute_tuning(struct mmc_host *mmc, u32 opcode)
622 {
623 	struct mmci_host *host = mmc_priv(mmc);
624 	struct sdmmc_dlyb *dlyb = host->variant_priv;
625 	u32 clk;
626 	int ret;
627 
628 	if ((host->mmc->ios.timing != MMC_TIMING_UHS_SDR104 &&
629 	     host->mmc->ios.timing != MMC_TIMING_MMC_HS200) ||
630 	    host->mmc->actual_clock <= 50000000)
631 		return 0;
632 
633 	if (!dlyb || !dlyb->base)
634 		return -EINVAL;
635 
636 	ret = dlyb->ops->dlyb_enable(dlyb);
637 	if (ret)
638 		return ret;
639 
640 	/*
641 	 * SDMMC_FBCK is selected when an external Delay Block is needed
642 	 * with SDR104 or HS200.
643 	 */
644 	clk = host->clk_reg;
645 	clk &= ~MCI_STM32_CLK_SEL_MSK;
646 	clk |= MCI_STM32_CLK_SELFBCK;
647 	mmci_write_clkreg(host, clk);
648 
649 	ret = dlyb->ops->tuning_prepare(host);
650 	if (ret)
651 		return ret;
652 
653 	return sdmmc_dlyb_phase_tuning(host, opcode);
654 }
655 
656 static void sdmmc_pre_sig_volt_vswitch(struct mmci_host *host)
657 {
658 	/* clear the voltage switch completion flag */
659 	writel_relaxed(MCI_STM32_VSWENDC, host->base + MMCICLEAR);
660 	/* enable Voltage switch procedure */
661 	mmci_write_pwrreg(host, host->pwr_reg | MCI_STM32_VSWITCHEN);
662 }
663 
664 static int sdmmc_post_sig_volt_switch(struct mmci_host *host,
665 				      struct mmc_ios *ios)
666 {
667 	unsigned long flags;
668 	u32 status;
669 	int ret = 0;
670 
671 	spin_lock_irqsave(&host->lock, flags);
672 	if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_180 &&
673 	    host->pwr_reg & MCI_STM32_VSWITCHEN) {
674 		mmci_write_pwrreg(host, host->pwr_reg | MCI_STM32_VSWITCH);
675 		spin_unlock_irqrestore(&host->lock, flags);
676 
677 		/* wait voltage switch completion while 10ms */
678 		ret = readl_relaxed_poll_timeout(host->base + MMCISTATUS,
679 						 status,
680 						 (status & MCI_STM32_VSWEND),
681 						 10, SDMMC_VSWEND_TIMEOUT_US);
682 
683 		writel_relaxed(MCI_STM32_VSWENDC | MCI_STM32_CKSTOPC,
684 			       host->base + MMCICLEAR);
685 		spin_lock_irqsave(&host->lock, flags);
686 		mmci_write_pwrreg(host, host->pwr_reg &
687 				  ~(MCI_STM32_VSWITCHEN | MCI_STM32_VSWITCH));
688 	}
689 	spin_unlock_irqrestore(&host->lock, flags);
690 
691 	return ret;
692 }
693 
694 static struct mmci_host_ops sdmmc_variant_ops = {
695 	.validate_data = sdmmc_idma_validate_data,
696 	.prep_data = sdmmc_idma_prep_data,
697 	.unprep_data = sdmmc_idma_unprep_data,
698 	.get_datactrl_cfg = sdmmc_get_dctrl_cfg,
699 	.dma_setup = sdmmc_idma_setup,
700 	.dma_start = sdmmc_idma_start,
701 	.dma_finalize = sdmmc_idma_finalize,
702 	.dma_error = sdmmc_idma_error,
703 	.set_clkreg = mmci_sdmmc_set_clkreg,
704 	.set_pwrreg = mmci_sdmmc_set_pwrreg,
705 	.busy_complete = sdmmc_busy_complete,
706 	.pre_sig_volt_switch = sdmmc_pre_sig_volt_vswitch,
707 	.post_sig_volt_switch = sdmmc_post_sig_volt_switch,
708 };
709 
710 static struct sdmmc_tuning_ops dlyb_tuning_mp15_ops = {
711 	.dlyb_enable = sdmmc_dlyb_mp15_enable,
712 	.set_input_ck = sdmmc_dlyb_mp15_input_ck,
713 	.tuning_prepare = sdmmc_dlyb_mp15_prepare,
714 	.set_cfg = sdmmc_dlyb_mp15_set_cfg,
715 };
716 
717 static struct sdmmc_tuning_ops dlyb_tuning_mp25_ops = {
718 	.dlyb_enable = sdmmc_dlyb_mp25_enable,
719 	.tuning_prepare = sdmmc_dlyb_mp25_prepare,
720 	.set_cfg = sdmmc_dlyb_mp25_set_cfg,
721 };
722 
723 void sdmmc_variant_init(struct mmci_host *host)
724 {
725 	struct device_node *np = host->mmc->parent->of_node;
726 	void __iomem *base_dlyb;
727 	struct sdmmc_dlyb *dlyb;
728 
729 	host->ops = &sdmmc_variant_ops;
730 	host->pwr_reg = readl_relaxed(host->base + MMCIPOWER);
731 
732 	base_dlyb = devm_of_iomap(mmc_dev(host->mmc), np, 1, NULL);
733 	if (IS_ERR(base_dlyb))
734 		return;
735 
736 	dlyb = devm_kzalloc(mmc_dev(host->mmc), sizeof(*dlyb), GFP_KERNEL);
737 	if (!dlyb)
738 		return;
739 
740 	dlyb->base = base_dlyb;
741 	if (of_device_is_compatible(np, "st,stm32mp25-sdmmc2"))
742 		dlyb->ops = &dlyb_tuning_mp25_ops;
743 	else
744 		dlyb->ops = &dlyb_tuning_mp15_ops;
745 
746 	host->variant_priv = dlyb;
747 	host->mmc_ops->execute_tuning = sdmmc_execute_tuning;
748 }
749