xref: /openbmc/linux/drivers/mmc/host/sdhci-sprd.c (revision 3213486f)
1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Secure Digital Host Controller
4 //
5 // Copyright (C) 2018 Spreadtrum, Inc.
6 // Author: Chunyan Zhang <chunyan.zhang@unisoc.com>
7 
8 #include <linux/delay.h>
9 #include <linux/dma-mapping.h>
10 #include <linux/highmem.h>
11 #include <linux/module.h>
12 #include <linux/of.h>
13 #include <linux/of_device.h>
14 #include <linux/of_gpio.h>
15 #include <linux/platform_device.h>
16 #include <linux/pm_runtime.h>
17 #include <linux/regulator/consumer.h>
18 #include <linux/slab.h>
19 
20 #include "sdhci-pltfm.h"
21 
22 /* SDHCI_ARGUMENT2 register high 16bit */
23 #define SDHCI_SPRD_ARG2_STUFF		GENMASK(31, 16)
24 
25 #define SDHCI_SPRD_REG_32_DLL_DLY_OFFSET	0x208
26 #define  SDHCIBSPRD_IT_WR_DLY_INV		BIT(5)
27 #define  SDHCI_SPRD_BIT_CMD_DLY_INV		BIT(13)
28 #define  SDHCI_SPRD_BIT_POSRD_DLY_INV		BIT(21)
29 #define  SDHCI_SPRD_BIT_NEGRD_DLY_INV		BIT(29)
30 
31 #define SDHCI_SPRD_REG_32_BUSY_POSI		0x250
32 #define  SDHCI_SPRD_BIT_OUTR_CLK_AUTO_EN	BIT(25)
33 #define  SDHCI_SPRD_BIT_INNR_CLK_AUTO_EN	BIT(24)
34 
35 #define SDHCI_SPRD_REG_DEBOUNCE		0x28C
36 #define  SDHCI_SPRD_BIT_DLL_BAK		BIT(0)
37 #define  SDHCI_SPRD_BIT_DLL_VAL		BIT(1)
38 
39 #define  SDHCI_SPRD_INT_SIGNAL_MASK	0x1B7F410B
40 
41 /* SDHCI_HOST_CONTROL2 */
42 #define  SDHCI_SPRD_CTRL_HS200		0x0005
43 #define  SDHCI_SPRD_CTRL_HS400		0x0006
44 
45 /*
46  * According to the standard specification, BIT(3) of SDHCI_SOFTWARE_RESET is
47  * reserved, and only used on Spreadtrum's design, the hardware cannot work
48  * if this bit is cleared.
49  * 1 : normal work
50  * 0 : hardware reset
51  */
52 #define  SDHCI_HW_RESET_CARD		BIT(3)
53 
54 #define SDHCI_SPRD_MAX_CUR		0xFFFFFF
55 #define SDHCI_SPRD_CLK_MAX_DIV		1023
56 
57 #define SDHCI_SPRD_CLK_DEF_RATE		26000000
58 
59 struct sdhci_sprd_host {
60 	u32 version;
61 	struct clk *clk_sdio;
62 	struct clk *clk_enable;
63 	u32 base_rate;
64 	int flags; /* backup of host attribute */
65 };
66 
67 #define TO_SPRD_HOST(host) sdhci_pltfm_priv(sdhci_priv(host))
68 
69 static void sdhci_sprd_init_config(struct sdhci_host *host)
70 {
71 	u16 val;
72 
73 	/* set dll backup mode */
74 	val = sdhci_readl(host, SDHCI_SPRD_REG_DEBOUNCE);
75 	val |= SDHCI_SPRD_BIT_DLL_BAK | SDHCI_SPRD_BIT_DLL_VAL;
76 	sdhci_writel(host, val, SDHCI_SPRD_REG_DEBOUNCE);
77 }
78 
79 static inline u32 sdhci_sprd_readl(struct sdhci_host *host, int reg)
80 {
81 	if (unlikely(reg == SDHCI_MAX_CURRENT))
82 		return SDHCI_SPRD_MAX_CUR;
83 
84 	return readl_relaxed(host->ioaddr + reg);
85 }
86 
87 static inline void sdhci_sprd_writel(struct sdhci_host *host, u32 val, int reg)
88 {
89 	/* SDHCI_MAX_CURRENT is reserved on Spreadtrum's platform */
90 	if (unlikely(reg == SDHCI_MAX_CURRENT))
91 		return;
92 
93 	if (unlikely(reg == SDHCI_SIGNAL_ENABLE || reg == SDHCI_INT_ENABLE))
94 		val = val & SDHCI_SPRD_INT_SIGNAL_MASK;
95 
96 	writel_relaxed(val, host->ioaddr + reg);
97 }
98 
99 static inline void sdhci_sprd_writew(struct sdhci_host *host, u16 val, int reg)
100 {
101 	/* SDHCI_BLOCK_COUNT is Read Only on Spreadtrum's platform */
102 	if (unlikely(reg == SDHCI_BLOCK_COUNT))
103 		return;
104 
105 	writew_relaxed(val, host->ioaddr + reg);
106 }
107 
108 static inline void sdhci_sprd_writeb(struct sdhci_host *host, u8 val, int reg)
109 {
110 	/*
111 	 * Since BIT(3) of SDHCI_SOFTWARE_RESET is reserved according to the
112 	 * standard specification, sdhci_reset() write this register directly
113 	 * without checking other reserved bits, that will clear BIT(3) which
114 	 * is defined as hardware reset on Spreadtrum's platform and clearing
115 	 * it by mistake will lead the card not work. So here we need to work
116 	 * around it.
117 	 */
118 	if (unlikely(reg == SDHCI_SOFTWARE_RESET)) {
119 		if (readb_relaxed(host->ioaddr + reg) & SDHCI_HW_RESET_CARD)
120 			val |= SDHCI_HW_RESET_CARD;
121 	}
122 
123 	writeb_relaxed(val, host->ioaddr + reg);
124 }
125 
126 static inline void sdhci_sprd_sd_clk_off(struct sdhci_host *host)
127 {
128 	u16 ctrl = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
129 
130 	ctrl &= ~SDHCI_CLOCK_CARD_EN;
131 	sdhci_writew(host, ctrl, SDHCI_CLOCK_CONTROL);
132 }
133 
134 static inline void
135 sdhci_sprd_set_dll_invert(struct sdhci_host *host, u32 mask, bool en)
136 {
137 	u32 dll_dly_offset;
138 
139 	dll_dly_offset = sdhci_readl(host, SDHCI_SPRD_REG_32_DLL_DLY_OFFSET);
140 	if (en)
141 		dll_dly_offset |= mask;
142 	else
143 		dll_dly_offset &= ~mask;
144 	sdhci_writel(host, dll_dly_offset, SDHCI_SPRD_REG_32_DLL_DLY_OFFSET);
145 }
146 
147 static inline u32 sdhci_sprd_calc_div(u32 base_clk, u32 clk)
148 {
149 	u32 div;
150 
151 	/* select 2x clock source */
152 	if (base_clk <= clk * 2)
153 		return 0;
154 
155 	div = (u32) (base_clk / (clk * 2));
156 
157 	if ((base_clk / div) > (clk * 2))
158 		div++;
159 
160 	if (div > SDHCI_SPRD_CLK_MAX_DIV)
161 		div = SDHCI_SPRD_CLK_MAX_DIV;
162 
163 	if (div % 2)
164 		div = (div + 1) / 2;
165 	else
166 		div = div / 2;
167 
168 	return div;
169 }
170 
171 static inline void _sdhci_sprd_set_clock(struct sdhci_host *host,
172 					unsigned int clk)
173 {
174 	struct sdhci_sprd_host *sprd_host = TO_SPRD_HOST(host);
175 	u32 div, val, mask;
176 
177 	div = sdhci_sprd_calc_div(sprd_host->base_rate, clk);
178 
179 	clk |= ((div & 0x300) >> 2) | ((div & 0xFF) << 8);
180 	sdhci_enable_clk(host, clk);
181 
182 	/* enable auto gate sdhc_enable_auto_gate */
183 	val = sdhci_readl(host, SDHCI_SPRD_REG_32_BUSY_POSI);
184 	mask = SDHCI_SPRD_BIT_OUTR_CLK_AUTO_EN |
185 	       SDHCI_SPRD_BIT_INNR_CLK_AUTO_EN;
186 	if (mask != (val & mask)) {
187 		val |= mask;
188 		sdhci_writel(host, val, SDHCI_SPRD_REG_32_BUSY_POSI);
189 	}
190 }
191 
192 static void sdhci_sprd_set_clock(struct sdhci_host *host, unsigned int clock)
193 {
194 	bool en = false;
195 
196 	if (clock == 0) {
197 		sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
198 	} else if (clock != host->clock) {
199 		sdhci_sprd_sd_clk_off(host);
200 		_sdhci_sprd_set_clock(host, clock);
201 
202 		if (clock <= 400000)
203 			en = true;
204 		sdhci_sprd_set_dll_invert(host, SDHCI_SPRD_BIT_CMD_DLY_INV |
205 					  SDHCI_SPRD_BIT_POSRD_DLY_INV, en);
206 	} else {
207 		_sdhci_sprd_set_clock(host, clock);
208 	}
209 }
210 
211 static unsigned int sdhci_sprd_get_max_clock(struct sdhci_host *host)
212 {
213 	struct sdhci_sprd_host *sprd_host = TO_SPRD_HOST(host);
214 
215 	return clk_round_rate(sprd_host->clk_sdio, ULONG_MAX);
216 }
217 
218 static unsigned int sdhci_sprd_get_min_clock(struct sdhci_host *host)
219 {
220 	return 400000;
221 }
222 
223 static void sdhci_sprd_set_uhs_signaling(struct sdhci_host *host,
224 					 unsigned int timing)
225 {
226 	u16 ctrl_2;
227 
228 	if (timing == host->timing)
229 		return;
230 
231 	ctrl_2 = sdhci_readw(host, SDHCI_HOST_CONTROL2);
232 	/* Select Bus Speed Mode for host */
233 	ctrl_2 &= ~SDHCI_CTRL_UHS_MASK;
234 	switch (timing) {
235 	case MMC_TIMING_UHS_SDR12:
236 		ctrl_2 |= SDHCI_CTRL_UHS_SDR12;
237 		break;
238 	case MMC_TIMING_MMC_HS:
239 	case MMC_TIMING_SD_HS:
240 	case MMC_TIMING_UHS_SDR25:
241 		ctrl_2 |= SDHCI_CTRL_UHS_SDR25;
242 		break;
243 	case MMC_TIMING_UHS_SDR50:
244 		ctrl_2 |= SDHCI_CTRL_UHS_SDR50;
245 		break;
246 	case MMC_TIMING_UHS_SDR104:
247 		ctrl_2 |= SDHCI_CTRL_UHS_SDR104;
248 		break;
249 	case MMC_TIMING_UHS_DDR50:
250 	case MMC_TIMING_MMC_DDR52:
251 		ctrl_2 |= SDHCI_CTRL_UHS_DDR50;
252 		break;
253 	case MMC_TIMING_MMC_HS200:
254 		ctrl_2 |= SDHCI_SPRD_CTRL_HS200;
255 		break;
256 	case MMC_TIMING_MMC_HS400:
257 		ctrl_2 |= SDHCI_SPRD_CTRL_HS400;
258 		break;
259 	default:
260 		break;
261 	}
262 
263 	sdhci_writew(host, ctrl_2, SDHCI_HOST_CONTROL2);
264 }
265 
266 static void sdhci_sprd_hw_reset(struct sdhci_host *host)
267 {
268 	int val;
269 
270 	/*
271 	 * Note: don't use sdhci_writeb() API here since it is redirected to
272 	 * sdhci_sprd_writeb() in which we have a workaround for
273 	 * SDHCI_SOFTWARE_RESET which would make bit SDHCI_HW_RESET_CARD can
274 	 * not be cleared.
275 	 */
276 	val = readb_relaxed(host->ioaddr + SDHCI_SOFTWARE_RESET);
277 	val &= ~SDHCI_HW_RESET_CARD;
278 	writeb_relaxed(val, host->ioaddr + SDHCI_SOFTWARE_RESET);
279 	/* wait for 10 us */
280 	usleep_range(10, 20);
281 
282 	val |= SDHCI_HW_RESET_CARD;
283 	writeb_relaxed(val, host->ioaddr + SDHCI_SOFTWARE_RESET);
284 	usleep_range(300, 500);
285 }
286 
287 static struct sdhci_ops sdhci_sprd_ops = {
288 	.read_l = sdhci_sprd_readl,
289 	.write_l = sdhci_sprd_writel,
290 	.write_b = sdhci_sprd_writeb,
291 	.set_clock = sdhci_sprd_set_clock,
292 	.get_max_clock = sdhci_sprd_get_max_clock,
293 	.get_min_clock = sdhci_sprd_get_min_clock,
294 	.set_bus_width = sdhci_set_bus_width,
295 	.reset = sdhci_reset,
296 	.set_uhs_signaling = sdhci_sprd_set_uhs_signaling,
297 	.hw_reset = sdhci_sprd_hw_reset,
298 };
299 
300 static void sdhci_sprd_request(struct mmc_host *mmc, struct mmc_request *mrq)
301 {
302 	struct sdhci_host *host = mmc_priv(mmc);
303 	struct sdhci_sprd_host *sprd_host = TO_SPRD_HOST(host);
304 
305 	host->flags |= sprd_host->flags & SDHCI_AUTO_CMD23;
306 
307 	/*
308 	 * From version 4.10 onward, ARGUMENT2 register is also as 32-bit
309 	 * block count register which doesn't support stuff bits of
310 	 * CMD23 argument on Spreadtrum's sd host controller.
311 	 */
312 	if (host->version >= SDHCI_SPEC_410 &&
313 	    mrq->sbc && (mrq->sbc->arg & SDHCI_SPRD_ARG2_STUFF) &&
314 	    (host->flags & SDHCI_AUTO_CMD23))
315 		host->flags &= ~SDHCI_AUTO_CMD23;
316 
317 	sdhci_request(mmc, mrq);
318 }
319 
320 static const struct sdhci_pltfm_data sdhci_sprd_pdata = {
321 	.quirks = SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK,
322 	.quirks2 = SDHCI_QUIRK2_BROKEN_HS200 |
323 		   SDHCI_QUIRK2_USE_32BIT_BLK_CNT,
324 	.ops = &sdhci_sprd_ops,
325 };
326 
327 static int sdhci_sprd_probe(struct platform_device *pdev)
328 {
329 	struct sdhci_host *host;
330 	struct sdhci_sprd_host *sprd_host;
331 	struct clk *clk;
332 	int ret = 0;
333 
334 	host = sdhci_pltfm_init(pdev, &sdhci_sprd_pdata, sizeof(*sprd_host));
335 	if (IS_ERR(host))
336 		return PTR_ERR(host);
337 
338 	host->dma_mask = DMA_BIT_MASK(64);
339 	pdev->dev.dma_mask = &host->dma_mask;
340 	host->mmc_host_ops.request = sdhci_sprd_request;
341 
342 	host->mmc->caps = MMC_CAP_SD_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED |
343 		MMC_CAP_ERASE | MMC_CAP_CMD23;
344 	ret = mmc_of_parse(host->mmc);
345 	if (ret)
346 		goto pltfm_free;
347 
348 	sprd_host = TO_SPRD_HOST(host);
349 
350 	clk = devm_clk_get(&pdev->dev, "sdio");
351 	if (IS_ERR(clk)) {
352 		ret = PTR_ERR(clk);
353 		goto pltfm_free;
354 	}
355 	sprd_host->clk_sdio = clk;
356 	sprd_host->base_rate = clk_get_rate(sprd_host->clk_sdio);
357 	if (!sprd_host->base_rate)
358 		sprd_host->base_rate = SDHCI_SPRD_CLK_DEF_RATE;
359 
360 	clk = devm_clk_get(&pdev->dev, "enable");
361 	if (IS_ERR(clk)) {
362 		ret = PTR_ERR(clk);
363 		goto pltfm_free;
364 	}
365 	sprd_host->clk_enable = clk;
366 
367 	ret = clk_prepare_enable(sprd_host->clk_sdio);
368 	if (ret)
369 		goto pltfm_free;
370 
371 	clk_prepare_enable(sprd_host->clk_enable);
372 	if (ret)
373 		goto clk_disable;
374 
375 	sdhci_sprd_init_config(host);
376 	host->version = sdhci_readw(host, SDHCI_HOST_VERSION);
377 	sprd_host->version = ((host->version & SDHCI_VENDOR_VER_MASK) >>
378 			       SDHCI_VENDOR_VER_SHIFT);
379 
380 	pm_runtime_get_noresume(&pdev->dev);
381 	pm_runtime_set_active(&pdev->dev);
382 	pm_runtime_enable(&pdev->dev);
383 	pm_runtime_set_autosuspend_delay(&pdev->dev, 50);
384 	pm_runtime_use_autosuspend(&pdev->dev);
385 	pm_suspend_ignore_children(&pdev->dev, 1);
386 
387 	sdhci_enable_v4_mode(host);
388 
389 	ret = sdhci_setup_host(host);
390 	if (ret)
391 		goto pm_runtime_disable;
392 
393 	sprd_host->flags = host->flags;
394 
395 	ret = __sdhci_add_host(host);
396 	if (ret)
397 		goto err_cleanup_host;
398 
399 	pm_runtime_mark_last_busy(&pdev->dev);
400 	pm_runtime_put_autosuspend(&pdev->dev);
401 
402 	return 0;
403 
404 err_cleanup_host:
405 	sdhci_cleanup_host(host);
406 
407 pm_runtime_disable:
408 	pm_runtime_disable(&pdev->dev);
409 	pm_runtime_set_suspended(&pdev->dev);
410 
411 	clk_disable_unprepare(sprd_host->clk_enable);
412 
413 clk_disable:
414 	clk_disable_unprepare(sprd_host->clk_sdio);
415 
416 pltfm_free:
417 	sdhci_pltfm_free(pdev);
418 	return ret;
419 }
420 
421 static int sdhci_sprd_remove(struct platform_device *pdev)
422 {
423 	struct sdhci_host *host = platform_get_drvdata(pdev);
424 	struct sdhci_sprd_host *sprd_host = TO_SPRD_HOST(host);
425 	struct mmc_host *mmc = host->mmc;
426 
427 	mmc_remove_host(mmc);
428 	clk_disable_unprepare(sprd_host->clk_sdio);
429 	clk_disable_unprepare(sprd_host->clk_enable);
430 
431 	mmc_free_host(mmc);
432 
433 	return 0;
434 }
435 
436 static const struct of_device_id sdhci_sprd_of_match[] = {
437 	{ .compatible = "sprd,sdhci-r11", },
438 	{ }
439 };
440 MODULE_DEVICE_TABLE(of, sdhci_sprd_of_match);
441 
442 #ifdef CONFIG_PM
443 static int sdhci_sprd_runtime_suspend(struct device *dev)
444 {
445 	struct sdhci_host *host = dev_get_drvdata(dev);
446 	struct sdhci_sprd_host *sprd_host = TO_SPRD_HOST(host);
447 
448 	sdhci_runtime_suspend_host(host);
449 
450 	clk_disable_unprepare(sprd_host->clk_sdio);
451 	clk_disable_unprepare(sprd_host->clk_enable);
452 
453 	return 0;
454 }
455 
456 static int sdhci_sprd_runtime_resume(struct device *dev)
457 {
458 	struct sdhci_host *host = dev_get_drvdata(dev);
459 	struct sdhci_sprd_host *sprd_host = TO_SPRD_HOST(host);
460 	int ret;
461 
462 	ret = clk_prepare_enable(sprd_host->clk_enable);
463 	if (ret)
464 		return ret;
465 
466 	ret = clk_prepare_enable(sprd_host->clk_sdio);
467 	if (ret) {
468 		clk_disable_unprepare(sprd_host->clk_enable);
469 		return ret;
470 	}
471 
472 	sdhci_runtime_resume_host(host);
473 
474 	return 0;
475 }
476 #endif
477 
478 static const struct dev_pm_ops sdhci_sprd_pm_ops = {
479 	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
480 				pm_runtime_force_resume)
481 	SET_RUNTIME_PM_OPS(sdhci_sprd_runtime_suspend,
482 			   sdhci_sprd_runtime_resume, NULL)
483 };
484 
485 static struct platform_driver sdhci_sprd_driver = {
486 	.probe = sdhci_sprd_probe,
487 	.remove = sdhci_sprd_remove,
488 	.driver = {
489 		.name = "sdhci_sprd_r11",
490 		.of_match_table = of_match_ptr(sdhci_sprd_of_match),
491 		.pm = &sdhci_sprd_pm_ops,
492 	},
493 };
494 module_platform_driver(sdhci_sprd_driver);
495 
496 MODULE_DESCRIPTION("Spreadtrum sdio host controller r11 driver");
497 MODULE_LICENSE("GPL v2");
498 MODULE_ALIAS("platform:sdhci-sprd-r11");
499