xref: /openbmc/linux/drivers/mmc/host/dw_mmc-exynos.c (revision 4d75f5c664195b970e1cd2fd25b65b5eff257a0a)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Exynos Specific Extensions for Synopsys DW Multimedia Card Interface driver
4  *
5  * Copyright (C) 2012, Samsung Electronics Co., Ltd.
6  */
7 
8 #include <linux/module.h>
9 #include <linux/platform_device.h>
10 #include <linux/clk.h>
11 #include <linux/mmc/host.h>
12 #include <linux/mmc/mmc.h>
13 #include <linux/of.h>
14 #include <linux/of_gpio.h>
15 #include <linux/pm_runtime.h>
16 #include <linux/slab.h>
17 
18 #include "dw_mmc.h"
19 #include "dw_mmc-pltfm.h"
20 #include "dw_mmc-exynos.h"
21 
22 /* Variations in Exynos specific dw-mshc controller */
23 enum dw_mci_exynos_type {
24 	DW_MCI_TYPE_EXYNOS4210,
25 	DW_MCI_TYPE_EXYNOS4412,
26 	DW_MCI_TYPE_EXYNOS5250,
27 	DW_MCI_TYPE_EXYNOS5420,
28 	DW_MCI_TYPE_EXYNOS5420_SMU,
29 	DW_MCI_TYPE_EXYNOS7,
30 	DW_MCI_TYPE_EXYNOS7_SMU,
31 	DW_MCI_TYPE_EXYNOS7870,
32 	DW_MCI_TYPE_EXYNOS7870_SMU,
33 	DW_MCI_TYPE_ARTPEC8,
34 };
35 
36 /* Exynos implementation specific driver private data */
37 struct dw_mci_exynos_priv_data {
38 	enum dw_mci_exynos_type		ctrl_type;
39 	u8				ciu_div;
40 	u32				sdr_timing;
41 	u32				ddr_timing;
42 	u32				hs400_timing;
43 	u32				tuned_sample;
44 	u32				cur_speed;
45 	u32				dqs_delay;
46 	u32				saved_dqs_en;
47 	u32				saved_strobe_ctrl;
48 };
49 
50 static struct dw_mci_exynos_compatible {
51 	char				*compatible;
52 	enum dw_mci_exynos_type		ctrl_type;
53 } exynos_compat[] = {
54 	{
55 		.compatible	= "samsung,exynos4210-dw-mshc",
56 		.ctrl_type	= DW_MCI_TYPE_EXYNOS4210,
57 	}, {
58 		.compatible	= "samsung,exynos4412-dw-mshc",
59 		.ctrl_type	= DW_MCI_TYPE_EXYNOS4412,
60 	}, {
61 		.compatible	= "samsung,exynos5250-dw-mshc",
62 		.ctrl_type	= DW_MCI_TYPE_EXYNOS5250,
63 	}, {
64 		.compatible	= "samsung,exynos5420-dw-mshc",
65 		.ctrl_type	= DW_MCI_TYPE_EXYNOS5420,
66 	}, {
67 		.compatible	= "samsung,exynos5420-dw-mshc-smu",
68 		.ctrl_type	= DW_MCI_TYPE_EXYNOS5420_SMU,
69 	}, {
70 		.compatible	= "samsung,exynos7-dw-mshc",
71 		.ctrl_type	= DW_MCI_TYPE_EXYNOS7,
72 	}, {
73 		.compatible	= "samsung,exynos7-dw-mshc-smu",
74 		.ctrl_type	= DW_MCI_TYPE_EXYNOS7_SMU,
75 	}, {
76 		.compatible	= "samsung,exynos7870-dw-mshc",
77 		.ctrl_type	= DW_MCI_TYPE_EXYNOS7870,
78 	}, {
79 		.compatible	= "samsung,exynos7870-dw-mshc-smu",
80 		.ctrl_type	= DW_MCI_TYPE_EXYNOS7870_SMU,
81 	}, {
82 		.compatible	= "axis,artpec8-dw-mshc",
83 		.ctrl_type	= DW_MCI_TYPE_ARTPEC8,
84 	},
85 };
86 
dw_mci_exynos_get_ciu_div(struct dw_mci * host)87 static inline u8 dw_mci_exynos_get_ciu_div(struct dw_mci *host)
88 {
89 	struct dw_mci_exynos_priv_data *priv = host->priv;
90 
91 	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4412)
92 		return EXYNOS4412_FIXED_CIU_CLK_DIV;
93 	else if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4210)
94 		return EXYNOS4210_FIXED_CIU_CLK_DIV;
95 	else if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
96 			priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU ||
97 			priv->ctrl_type == DW_MCI_TYPE_EXYNOS7870 ||
98 			priv->ctrl_type == DW_MCI_TYPE_EXYNOS7870_SMU ||
99 			priv->ctrl_type == DW_MCI_TYPE_ARTPEC8)
100 		return SDMMC_CLKSEL_GET_DIV(mci_readl(host, CLKSEL64)) + 1;
101 	else
102 		return SDMMC_CLKSEL_GET_DIV(mci_readl(host, CLKSEL)) + 1;
103 }
104 
dw_mci_exynos_config_smu(struct dw_mci * host)105 static void dw_mci_exynos_config_smu(struct dw_mci *host)
106 {
107 	struct dw_mci_exynos_priv_data *priv = host->priv;
108 
109 	/*
110 	 * If Exynos is provided the Security management,
111 	 * set for non-ecryption mode at this time.
112 	 */
113 	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS5420_SMU ||
114 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU ||
115 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7870_SMU) {
116 		mci_writel(host, MPSBEGIN0, 0);
117 		mci_writel(host, MPSEND0, SDMMC_ENDING_SEC_NR_MAX);
118 		mci_writel(host, MPSCTRL0, SDMMC_MPSCTRL_SECURE_WRITE_BIT |
119 			   SDMMC_MPSCTRL_NON_SECURE_READ_BIT |
120 			   SDMMC_MPSCTRL_VALID |
121 			   SDMMC_MPSCTRL_NON_SECURE_WRITE_BIT);
122 	}
123 }
124 
dw_mci_exynos_priv_init(struct dw_mci * host)125 static int dw_mci_exynos_priv_init(struct dw_mci *host)
126 {
127 	struct dw_mci_exynos_priv_data *priv = host->priv;
128 
129 	dw_mci_exynos_config_smu(host);
130 
131 	if (priv->ctrl_type >= DW_MCI_TYPE_EXYNOS5420) {
132 		priv->saved_strobe_ctrl = mci_readl(host, HS400_DLINE_CTRL);
133 		priv->saved_dqs_en = mci_readl(host, HS400_DQS_EN);
134 		priv->saved_dqs_en |= AXI_NON_BLOCKING_WR;
135 		mci_writel(host, HS400_DQS_EN, priv->saved_dqs_en);
136 		if (!priv->dqs_delay)
137 			priv->dqs_delay =
138 				DQS_CTRL_GET_RD_DELAY(priv->saved_strobe_ctrl);
139 	}
140 
141 	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7870 ||
142 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7870_SMU) {
143 		/* Quirk needed for certain Exynos SoCs */
144 		host->quirks |= DW_MMC_QUIRK_FIFO64_32;
145 	}
146 
147 	if (priv->ctrl_type == DW_MCI_TYPE_ARTPEC8) {
148 		/* Quirk needed for the ARTPEC-8 SoC */
149 		host->quirks |= DW_MMC_QUIRK_EXTENDED_TMOUT;
150 	}
151 
152 	host->bus_hz /= (priv->ciu_div + 1);
153 
154 	return 0;
155 }
156 
dw_mci_exynos_set_clksel_timing(struct dw_mci * host,u32 timing)157 static void dw_mci_exynos_set_clksel_timing(struct dw_mci *host, u32 timing)
158 {
159 	struct dw_mci_exynos_priv_data *priv = host->priv;
160 	u32 clksel;
161 
162 	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
163 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU ||
164 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7870 ||
165 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7870_SMU ||
166 		priv->ctrl_type == DW_MCI_TYPE_ARTPEC8)
167 		clksel = mci_readl(host, CLKSEL64);
168 	else
169 		clksel = mci_readl(host, CLKSEL);
170 
171 	clksel = (clksel & ~SDMMC_CLKSEL_TIMING_MASK) | timing;
172 
173 	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
174 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU ||
175 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7870 ||
176 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7870_SMU ||
177 		priv->ctrl_type == DW_MCI_TYPE_ARTPEC8)
178 		mci_writel(host, CLKSEL64, clksel);
179 	else
180 		mci_writel(host, CLKSEL, clksel);
181 
182 	/*
183 	 * Exynos4412 and Exynos5250 extends the use of CMD register with the
184 	 * use of bit 29 (which is reserved on standard MSHC controllers) for
185 	 * optionally bypassing the HOLD register for command and data. The
186 	 * HOLD register should be bypassed in case there is no phase shift
187 	 * applied on CMD/DATA that is sent to the card.
188 	 */
189 	if (!SDMMC_CLKSEL_GET_DRV_WD3(clksel) && host->slot)
190 		set_bit(DW_MMC_CARD_NO_USE_HOLD, &host->slot->flags);
191 }
192 
193 #ifdef CONFIG_PM
dw_mci_exynos_runtime_resume(struct device * dev)194 static int dw_mci_exynos_runtime_resume(struct device *dev)
195 {
196 	struct dw_mci *host = dev_get_drvdata(dev);
197 	int ret;
198 
199 	ret = dw_mci_runtime_resume(dev);
200 	if (ret)
201 		return ret;
202 
203 	dw_mci_exynos_config_smu(host);
204 
205 	return ret;
206 }
207 #endif /* CONFIG_PM */
208 
209 #ifdef CONFIG_PM_SLEEP
210 /**
211  * dw_mci_exynos_suspend_noirq - Exynos-specific suspend code
212  * @dev: Device to suspend (this device)
213  *
214  * This ensures that device will be in runtime active state in
215  * dw_mci_exynos_resume_noirq after calling pm_runtime_force_resume()
216  */
dw_mci_exynos_suspend_noirq(struct device * dev)217 static int dw_mci_exynos_suspend_noirq(struct device *dev)
218 {
219 	pm_runtime_get_noresume(dev);
220 	return pm_runtime_force_suspend(dev);
221 }
222 
223 /**
224  * dw_mci_exynos_resume_noirq - Exynos-specific resume code
225  * @dev: Device to resume (this device)
226  *
227  * On exynos5420 there is a silicon errata that will sometimes leave the
228  * WAKEUP_INT bit in the CLKSEL register asserted.  This bit is 1 to indicate
229  * that it fired and we can clear it by writing a 1 back.  Clear it to prevent
230  * interrupts from going off constantly.
231  *
232  * We run this code on all exynos variants because it doesn't hurt.
233  */
dw_mci_exynos_resume_noirq(struct device * dev)234 static int dw_mci_exynos_resume_noirq(struct device *dev)
235 {
236 	struct dw_mci *host = dev_get_drvdata(dev);
237 	struct dw_mci_exynos_priv_data *priv = host->priv;
238 	u32 clksel;
239 	int ret;
240 
241 	ret = pm_runtime_force_resume(dev);
242 	if (ret)
243 		return ret;
244 
245 	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
246 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU ||
247 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7870 ||
248 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7870_SMU ||
249 		priv->ctrl_type == DW_MCI_TYPE_ARTPEC8)
250 		clksel = mci_readl(host, CLKSEL64);
251 	else
252 		clksel = mci_readl(host, CLKSEL);
253 
254 	if (clksel & SDMMC_CLKSEL_WAKEUP_INT) {
255 		if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
256 			priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU ||
257 			priv->ctrl_type == DW_MCI_TYPE_EXYNOS7870 ||
258 			priv->ctrl_type == DW_MCI_TYPE_EXYNOS7870_SMU ||
259 			priv->ctrl_type == DW_MCI_TYPE_ARTPEC8)
260 			mci_writel(host, CLKSEL64, clksel);
261 		else
262 			mci_writel(host, CLKSEL, clksel);
263 	}
264 
265 	pm_runtime_put(dev);
266 
267 	return 0;
268 }
269 #endif /* CONFIG_PM_SLEEP */
270 
dw_mci_exynos_config_hs400(struct dw_mci * host,u32 timing)271 static void dw_mci_exynos_config_hs400(struct dw_mci *host, u32 timing)
272 {
273 	struct dw_mci_exynos_priv_data *priv = host->priv;
274 	u32 dqs, strobe;
275 
276 	/*
277 	 * Not supported to configure register
278 	 * related to HS400
279 	 */
280 	if ((priv->ctrl_type < DW_MCI_TYPE_EXYNOS5420) ||
281 		(priv->ctrl_type == DW_MCI_TYPE_ARTPEC8)) {
282 		if (timing == MMC_TIMING_MMC_HS400)
283 			dev_warn(host->dev,
284 				 "cannot configure HS400, unsupported chipset\n");
285 		return;
286 	}
287 
288 	dqs = priv->saved_dqs_en;
289 	strobe = priv->saved_strobe_ctrl;
290 
291 	if (timing == MMC_TIMING_MMC_HS400) {
292 		dqs |= DATA_STROBE_EN;
293 		strobe = DQS_CTRL_RD_DELAY(strobe, priv->dqs_delay);
294 	} else if (timing == MMC_TIMING_UHS_SDR104) {
295 		dqs &= 0xffffff00;
296 	} else {
297 		dqs &= ~DATA_STROBE_EN;
298 	}
299 
300 	mci_writel(host, HS400_DQS_EN, dqs);
301 	mci_writel(host, HS400_DLINE_CTRL, strobe);
302 }
303 
dw_mci_exynos_adjust_clock(struct dw_mci * host,unsigned int wanted)304 static void dw_mci_exynos_adjust_clock(struct dw_mci *host, unsigned int wanted)
305 {
306 	struct dw_mci_exynos_priv_data *priv = host->priv;
307 	unsigned long actual;
308 	u8 div;
309 	int ret;
310 	/*
311 	 * Don't care if wanted clock is zero or
312 	 * ciu clock is unavailable
313 	 */
314 	if (!wanted || IS_ERR(host->ciu_clk))
315 		return;
316 
317 	/* Guaranteed minimum frequency for cclkin */
318 	if (wanted < EXYNOS_CCLKIN_MIN)
319 		wanted = EXYNOS_CCLKIN_MIN;
320 
321 	if (wanted == priv->cur_speed)
322 		return;
323 
324 	div = dw_mci_exynos_get_ciu_div(host);
325 	ret = clk_set_rate(host->ciu_clk, wanted * div);
326 	if (ret)
327 		dev_warn(host->dev,
328 			"failed to set clk-rate %u error: %d\n",
329 			wanted * div, ret);
330 	actual = clk_get_rate(host->ciu_clk);
331 	host->bus_hz = actual / div;
332 	priv->cur_speed = wanted;
333 	host->current_speed = 0;
334 }
335 
dw_mci_exynos_set_ios(struct dw_mci * host,struct mmc_ios * ios)336 static void dw_mci_exynos_set_ios(struct dw_mci *host, struct mmc_ios *ios)
337 {
338 	struct dw_mci_exynos_priv_data *priv = host->priv;
339 	unsigned int wanted = ios->clock;
340 	u32 timing = ios->timing, clksel;
341 
342 	switch (timing) {
343 	case MMC_TIMING_MMC_HS400:
344 		/* Update tuned sample timing */
345 		clksel = SDMMC_CLKSEL_UP_SAMPLE(
346 				priv->hs400_timing, priv->tuned_sample);
347 		wanted <<= 1;
348 		break;
349 	case MMC_TIMING_MMC_DDR52:
350 		clksel = priv->ddr_timing;
351 		/* Should be double rate for DDR mode */
352 		if (ios->bus_width == MMC_BUS_WIDTH_8)
353 			wanted <<= 1;
354 		break;
355 	case MMC_TIMING_UHS_SDR104:
356 	case MMC_TIMING_UHS_SDR50:
357 		clksel = (priv->sdr_timing & 0xfff8ffff) |
358 			(priv->ciu_div << 16);
359 		break;
360 	case MMC_TIMING_UHS_DDR50:
361 		clksel = (priv->ddr_timing & 0xfff8ffff) |
362 			(priv->ciu_div << 16);
363 		break;
364 	default:
365 		clksel = priv->sdr_timing;
366 	}
367 
368 	/* Set clock timing for the requested speed mode*/
369 	dw_mci_exynos_set_clksel_timing(host, clksel);
370 
371 	/* Configure setting for HS400 */
372 	dw_mci_exynos_config_hs400(host, timing);
373 
374 	/* Configure clock rate */
375 	dw_mci_exynos_adjust_clock(host, wanted);
376 }
377 
dw_mci_exynos_parse_dt(struct dw_mci * host)378 static int dw_mci_exynos_parse_dt(struct dw_mci *host)
379 {
380 	struct dw_mci_exynos_priv_data *priv;
381 	struct device_node *np = host->dev->of_node;
382 	u32 timing[2];
383 	u32 div = 0;
384 	int idx;
385 	int ret;
386 
387 	priv = devm_kzalloc(host->dev, sizeof(*priv), GFP_KERNEL);
388 	if (!priv)
389 		return -ENOMEM;
390 
391 	for (idx = 0; idx < ARRAY_SIZE(exynos_compat); idx++) {
392 		if (of_device_is_compatible(np, exynos_compat[idx].compatible))
393 			priv->ctrl_type = exynos_compat[idx].ctrl_type;
394 	}
395 
396 	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4412)
397 		priv->ciu_div = EXYNOS4412_FIXED_CIU_CLK_DIV - 1;
398 	else if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4210)
399 		priv->ciu_div = EXYNOS4210_FIXED_CIU_CLK_DIV - 1;
400 	else {
401 		of_property_read_u32(np, "samsung,dw-mshc-ciu-div", &div);
402 		priv->ciu_div = div;
403 	}
404 
405 	ret = of_property_read_u32_array(np,
406 			"samsung,dw-mshc-sdr-timing", timing, 2);
407 	if (ret)
408 		return ret;
409 
410 	priv->sdr_timing = SDMMC_CLKSEL_TIMING(timing[0], timing[1], div);
411 
412 	ret = of_property_read_u32_array(np,
413 			"samsung,dw-mshc-ddr-timing", timing, 2);
414 	if (ret)
415 		return ret;
416 
417 	priv->ddr_timing = SDMMC_CLKSEL_TIMING(timing[0], timing[1], div);
418 
419 	ret = of_property_read_u32_array(np,
420 			"samsung,dw-mshc-hs400-timing", timing, 2);
421 	if (!ret && of_property_read_u32(np,
422 				"samsung,read-strobe-delay", &priv->dqs_delay))
423 		dev_dbg(host->dev,
424 			"read-strobe-delay is not found, assuming usage of default value\n");
425 
426 	priv->hs400_timing = SDMMC_CLKSEL_TIMING(timing[0], timing[1],
427 						HS400_FIXED_CIU_CLK_DIV);
428 	host->priv = priv;
429 	return 0;
430 }
431 
dw_mci_exynos_get_clksmpl(struct dw_mci * host)432 static inline u8 dw_mci_exynos_get_clksmpl(struct dw_mci *host)
433 {
434 	struct dw_mci_exynos_priv_data *priv = host->priv;
435 
436 	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
437 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU ||
438 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7870 ||
439 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7870_SMU ||
440 		priv->ctrl_type == DW_MCI_TYPE_ARTPEC8)
441 		return SDMMC_CLKSEL_CCLK_SAMPLE(mci_readl(host, CLKSEL64));
442 	else
443 		return SDMMC_CLKSEL_CCLK_SAMPLE(mci_readl(host, CLKSEL));
444 }
445 
dw_mci_exynos_set_clksmpl(struct dw_mci * host,u8 sample)446 static inline void dw_mci_exynos_set_clksmpl(struct dw_mci *host, u8 sample)
447 {
448 	u32 clksel;
449 	struct dw_mci_exynos_priv_data *priv = host->priv;
450 
451 	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
452 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU ||
453 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7870 ||
454 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7870_SMU ||
455 		priv->ctrl_type == DW_MCI_TYPE_ARTPEC8)
456 		clksel = mci_readl(host, CLKSEL64);
457 	else
458 		clksel = mci_readl(host, CLKSEL);
459 	clksel = SDMMC_CLKSEL_UP_SAMPLE(clksel, sample);
460 	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
461 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU ||
462 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7870 ||
463 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7870_SMU ||
464 		priv->ctrl_type == DW_MCI_TYPE_ARTPEC8)
465 		mci_writel(host, CLKSEL64, clksel);
466 	else
467 		mci_writel(host, CLKSEL, clksel);
468 }
469 
dw_mci_exynos_move_next_clksmpl(struct dw_mci * host)470 static inline u8 dw_mci_exynos_move_next_clksmpl(struct dw_mci *host)
471 {
472 	struct dw_mci_exynos_priv_data *priv = host->priv;
473 	u32 clksel;
474 	u8 sample;
475 
476 	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
477 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU ||
478 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7870 ||
479 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7870_SMU ||
480 		priv->ctrl_type == DW_MCI_TYPE_ARTPEC8)
481 		clksel = mci_readl(host, CLKSEL64);
482 	else
483 		clksel = mci_readl(host, CLKSEL);
484 
485 	sample = (clksel + 1) & 0x7;
486 	clksel = SDMMC_CLKSEL_UP_SAMPLE(clksel, sample);
487 
488 	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
489 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU ||
490 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7870 ||
491 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7870_SMU ||
492 		priv->ctrl_type == DW_MCI_TYPE_ARTPEC8)
493 		mci_writel(host, CLKSEL64, clksel);
494 	else
495 		mci_writel(host, CLKSEL, clksel);
496 
497 	return sample;
498 }
499 
dw_mci_exynos_get_best_clksmpl(u8 candidates)500 static s8 dw_mci_exynos_get_best_clksmpl(u8 candidates)
501 {
502 	const u8 iter = 8;
503 	u8 __c;
504 	s8 i, loc = -1;
505 
506 	for (i = 0; i < iter; i++) {
507 		__c = ror8(candidates, i);
508 		if ((__c & 0xc7) == 0xc7) {
509 			loc = i;
510 			goto out;
511 		}
512 	}
513 
514 	for (i = 0; i < iter; i++) {
515 		__c = ror8(candidates, i);
516 		if ((__c & 0x83) == 0x83) {
517 			loc = i;
518 			goto out;
519 		}
520 	}
521 
522 	/*
523 	 * If there is no cadiates value, then it needs to return -EIO.
524 	 * If there are candidates values and don't find bset clk sample value,
525 	 * then use a first candidates clock sample value.
526 	 */
527 	for (i = 0; i < iter; i++) {
528 		__c = ror8(candidates, i);
529 		if ((__c & 0x1) == 0x1) {
530 			loc = i;
531 			goto out;
532 		}
533 	}
534 out:
535 	return loc;
536 }
537 
dw_mci_exynos_execute_tuning(struct dw_mci_slot * slot,u32 opcode)538 static int dw_mci_exynos_execute_tuning(struct dw_mci_slot *slot, u32 opcode)
539 {
540 	struct dw_mci *host = slot->host;
541 	struct dw_mci_exynos_priv_data *priv = host->priv;
542 	struct mmc_host *mmc = slot->mmc;
543 	u8 start_smpl, smpl, candidates = 0;
544 	s8 found;
545 	int ret = 0;
546 
547 	start_smpl = dw_mci_exynos_get_clksmpl(host);
548 
549 	do {
550 		mci_writel(host, TMOUT, ~0);
551 		smpl = dw_mci_exynos_move_next_clksmpl(host);
552 
553 		if (!mmc_send_tuning(mmc, opcode, NULL))
554 			candidates |= (1 << smpl);
555 
556 	} while (start_smpl != smpl);
557 
558 	found = dw_mci_exynos_get_best_clksmpl(candidates);
559 	if (found >= 0) {
560 		dw_mci_exynos_set_clksmpl(host, found);
561 		priv->tuned_sample = found;
562 	} else {
563 		ret = -EIO;
564 		dev_warn(&mmc->class_dev,
565 			"There is no candidates value about clksmpl!\n");
566 	}
567 
568 	return ret;
569 }
570 
dw_mci_exynos_prepare_hs400_tuning(struct dw_mci * host,struct mmc_ios * ios)571 static int dw_mci_exynos_prepare_hs400_tuning(struct dw_mci *host,
572 					struct mmc_ios *ios)
573 {
574 	struct dw_mci_exynos_priv_data *priv = host->priv;
575 
576 	dw_mci_exynos_set_clksel_timing(host, priv->hs400_timing);
577 	dw_mci_exynos_adjust_clock(host, (ios->clock) << 1);
578 
579 	return 0;
580 }
581 
dw_mci_exynos_set_data_timeout(struct dw_mci * host,unsigned int timeout_ns)582 static void dw_mci_exynos_set_data_timeout(struct dw_mci *host,
583 					   unsigned int timeout_ns)
584 {
585 	u32 clk_div, tmout;
586 	u64 tmp;
587 	unsigned int tmp2;
588 
589 	clk_div = (mci_readl(host, CLKDIV) & 0xFF) * 2;
590 	if (clk_div == 0)
591 		clk_div = 1;
592 
593 	tmp = DIV_ROUND_UP_ULL((u64)timeout_ns * host->bus_hz, NSEC_PER_SEC);
594 	tmp = DIV_ROUND_UP_ULL(tmp, clk_div);
595 
596 	/* TMOUT[7:0] (RESPONSE_TIMEOUT) */
597 	tmout = 0xFF; /* Set maximum */
598 
599 	/*
600 	 * Extended HW timer (max = 0x6FFFFF2):
601 	 * ((TMOUT[10:8] - 1) * 0xFFFFFF + TMOUT[31:11] * 8)
602 	 */
603 	if (!tmp || tmp > 0x6FFFFF2)
604 		tmout |= (0xFFFFFF << 8);
605 	else {
606 		/* TMOUT[10:8] */
607 		tmp2 = (((unsigned int)tmp / 0xFFFFFF) + 1) & 0x7;
608 		tmout |= tmp2 << 8;
609 
610 		/* TMOUT[31:11] */
611 		tmp = tmp - ((tmp2 - 1) * 0xFFFFFF);
612 		tmout |= (tmp & 0xFFFFF8) << 8;
613 	}
614 
615 	mci_writel(host, TMOUT, tmout);
616 	dev_dbg(host->dev, "timeout_ns: %u => TMOUT[31:8]: %#08x",
617 		timeout_ns, tmout >> 8);
618 }
619 
dw_mci_exynos_get_drto_clks(struct dw_mci * host)620 static u32 dw_mci_exynos_get_drto_clks(struct dw_mci *host)
621 {
622 	u32 drto_clks;
623 
624 	drto_clks = mci_readl(host, TMOUT) >> 8;
625 
626 	return (((drto_clks & 0x7) - 1) * 0xFFFFFF) + ((drto_clks & 0xFFFFF8));
627 }
628 
629 /* Common capabilities of Exynos4/Exynos5 SoC */
630 static unsigned long exynos_dwmmc_caps[4] = {
631 	MMC_CAP_1_8V_DDR | MMC_CAP_8_BIT_DATA,
632 	0,
633 	0,
634 	0,
635 };
636 
637 static const struct dw_mci_drv_data exynos_drv_data = {
638 	.caps			= exynos_dwmmc_caps,
639 	.num_caps		= ARRAY_SIZE(exynos_dwmmc_caps),
640 	.common_caps		= MMC_CAP_CMD23,
641 	.init			= dw_mci_exynos_priv_init,
642 	.set_ios		= dw_mci_exynos_set_ios,
643 	.parse_dt		= dw_mci_exynos_parse_dt,
644 	.execute_tuning		= dw_mci_exynos_execute_tuning,
645 	.prepare_hs400_tuning	= dw_mci_exynos_prepare_hs400_tuning,
646 };
647 
648 static const struct dw_mci_drv_data artpec_drv_data = {
649 	.common_caps		= MMC_CAP_CMD23,
650 	.init			= dw_mci_exynos_priv_init,
651 	.set_ios		= dw_mci_exynos_set_ios,
652 	.parse_dt		= dw_mci_exynos_parse_dt,
653 	.execute_tuning		= dw_mci_exynos_execute_tuning,
654 	.set_data_timeout		= dw_mci_exynos_set_data_timeout,
655 	.get_drto_clks		= dw_mci_exynos_get_drto_clks,
656 };
657 
658 static const struct of_device_id dw_mci_exynos_match[] = {
659 	{ .compatible = "samsung,exynos4412-dw-mshc",
660 			.data = &exynos_drv_data, },
661 	{ .compatible = "samsung,exynos5250-dw-mshc",
662 			.data = &exynos_drv_data, },
663 	{ .compatible = "samsung,exynos5420-dw-mshc",
664 			.data = &exynos_drv_data, },
665 	{ .compatible = "samsung,exynos5420-dw-mshc-smu",
666 			.data = &exynos_drv_data, },
667 	{ .compatible = "samsung,exynos7-dw-mshc",
668 			.data = &exynos_drv_data, },
669 	{ .compatible = "samsung,exynos7-dw-mshc-smu",
670 			.data = &exynos_drv_data, },
671 	{ .compatible = "samsung,exynos7870-dw-mshc",
672 			.data = &exynos_drv_data, },
673 	{ .compatible = "samsung,exynos7870-dw-mshc-smu",
674 			.data = &exynos_drv_data, },
675 	{ .compatible = "axis,artpec8-dw-mshc",
676 			.data = &artpec_drv_data, },
677 	{},
678 };
679 MODULE_DEVICE_TABLE(of, dw_mci_exynos_match);
680 
dw_mci_exynos_probe(struct platform_device * pdev)681 static int dw_mci_exynos_probe(struct platform_device *pdev)
682 {
683 	const struct dw_mci_drv_data *drv_data;
684 	const struct of_device_id *match;
685 	int ret;
686 
687 	match = of_match_node(dw_mci_exynos_match, pdev->dev.of_node);
688 	drv_data = match->data;
689 
690 	pm_runtime_get_noresume(&pdev->dev);
691 	pm_runtime_set_active(&pdev->dev);
692 	pm_runtime_enable(&pdev->dev);
693 
694 	ret = dw_mci_pltfm_register(pdev, drv_data);
695 	if (ret) {
696 		pm_runtime_disable(&pdev->dev);
697 		pm_runtime_set_suspended(&pdev->dev);
698 		pm_runtime_put_noidle(&pdev->dev);
699 
700 		return ret;
701 	}
702 
703 	return 0;
704 }
705 
dw_mci_exynos_remove(struct platform_device * pdev)706 static void dw_mci_exynos_remove(struct platform_device *pdev)
707 {
708 	pm_runtime_disable(&pdev->dev);
709 	pm_runtime_set_suspended(&pdev->dev);
710 	pm_runtime_put_noidle(&pdev->dev);
711 
712 	dw_mci_pltfm_remove(pdev);
713 }
714 
715 static const struct dev_pm_ops dw_mci_exynos_pmops = {
716 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(dw_mci_exynos_suspend_noirq,
717 				      dw_mci_exynos_resume_noirq)
718 	SET_RUNTIME_PM_OPS(dw_mci_runtime_suspend,
719 			   dw_mci_exynos_runtime_resume,
720 			   NULL)
721 };
722 
723 static struct platform_driver dw_mci_exynos_pltfm_driver = {
724 	.probe		= dw_mci_exynos_probe,
725 	.remove_new	= dw_mci_exynos_remove,
726 	.driver		= {
727 		.name		= "dwmmc_exynos",
728 		.probe_type	= PROBE_PREFER_ASYNCHRONOUS,
729 		.of_match_table	= dw_mci_exynos_match,
730 		.pm		= &dw_mci_exynos_pmops,
731 	},
732 };
733 
734 module_platform_driver(dw_mci_exynos_pltfm_driver);
735 
736 MODULE_DESCRIPTION("Samsung Specific DW-MSHC Driver Extension");
737 MODULE_AUTHOR("Thomas Abraham <thomas.ab@samsung.com");
738 MODULE_LICENSE("GPL v2");
739 MODULE_ALIAS("platform:dwmmc_exynos");
740