xref: /linux/drivers/mmc/host/sdhci-tegra.c (revision 0883c2c06fb5bcf5b9e008270827e63c09a88c1e)
1 /*
2  * Copyright (C) 2010 Google, Inc.
3  *
4  * This software is licensed under the terms of the GNU General Public
5  * License version 2, as published by the Free Software Foundation, and
6  * may be copied, distributed, and modified under those terms.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  *
13  */
14 
15 #include <linux/delay.h>
16 #include <linux/err.h>
17 #include <linux/module.h>
18 #include <linux/init.h>
19 #include <linux/platform_device.h>
20 #include <linux/clk.h>
21 #include <linux/io.h>
22 #include <linux/of.h>
23 #include <linux/of_device.h>
24 #include <linux/mmc/card.h>
25 #include <linux/mmc/host.h>
26 #include <linux/mmc/mmc.h>
27 #include <linux/mmc/slot-gpio.h>
28 #include <linux/gpio/consumer.h>
29 
30 #include "sdhci-pltfm.h"
31 
32 /* Tegra SDHOST controller vendor register definitions */
33 #define SDHCI_TEGRA_VENDOR_CLOCK_CTRL			0x100
34 #define SDHCI_CLOCK_CTRL_TAP_MASK			0x00ff0000
35 #define SDHCI_CLOCK_CTRL_TAP_SHIFT			16
36 #define SDHCI_CLOCK_CTRL_SDR50_TUNING_OVERRIDE		BIT(5)
37 #define SDHCI_CLOCK_CTRL_PADPIPE_CLKEN_OVERRIDE		BIT(3)
38 #define SDHCI_CLOCK_CTRL_SPI_MODE_CLKEN_OVERRIDE	BIT(2)
39 
40 #define SDHCI_TEGRA_VENDOR_MISC_CTRL		0x120
41 #define SDHCI_MISC_CTRL_ENABLE_SDR104		0x8
42 #define SDHCI_MISC_CTRL_ENABLE_SDR50		0x10
43 #define SDHCI_MISC_CTRL_ENABLE_SDHCI_SPEC_300	0x20
44 #define SDHCI_MISC_CTRL_ENABLE_DDR50		0x200
45 
46 #define SDHCI_TEGRA_AUTO_CAL_CONFIG		0x1e4
47 #define SDHCI_AUTO_CAL_START			BIT(31)
48 #define SDHCI_AUTO_CAL_ENABLE			BIT(29)
49 
50 #define NVQUIRK_FORCE_SDHCI_SPEC_200	BIT(0)
51 #define NVQUIRK_ENABLE_BLOCK_GAP_DET	BIT(1)
52 #define NVQUIRK_ENABLE_SDHCI_SPEC_300	BIT(2)
53 #define NVQUIRK_ENABLE_SDR50		BIT(3)
54 #define NVQUIRK_ENABLE_SDR104		BIT(4)
55 #define NVQUIRK_ENABLE_DDR50		BIT(5)
56 #define NVQUIRK_HAS_PADCALIB		BIT(6)
57 
58 struct sdhci_tegra_soc_data {
59 	const struct sdhci_pltfm_data *pdata;
60 	u32 nvquirks;
61 };
62 
63 struct sdhci_tegra {
64 	const struct sdhci_tegra_soc_data *soc_data;
65 	struct gpio_desc *power_gpio;
66 	bool ddr_signaling;
67 	bool pad_calib_required;
68 };
69 
70 static u16 tegra_sdhci_readw(struct sdhci_host *host, int reg)
71 {
72 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
73 	struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
74 	const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
75 
76 	if (unlikely((soc_data->nvquirks & NVQUIRK_FORCE_SDHCI_SPEC_200) &&
77 			(reg == SDHCI_HOST_VERSION))) {
78 		/* Erratum: Version register is invalid in HW. */
79 		return SDHCI_SPEC_200;
80 	}
81 
82 	return readw(host->ioaddr + reg);
83 }
84 
85 static void tegra_sdhci_writew(struct sdhci_host *host, u16 val, int reg)
86 {
87 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
88 
89 	switch (reg) {
90 	case SDHCI_TRANSFER_MODE:
91 		/*
92 		 * Postpone this write, we must do it together with a
93 		 * command write that is down below.
94 		 */
95 		pltfm_host->xfer_mode_shadow = val;
96 		return;
97 	case SDHCI_COMMAND:
98 		writel((val << 16) | pltfm_host->xfer_mode_shadow,
99 			host->ioaddr + SDHCI_TRANSFER_MODE);
100 		return;
101 	}
102 
103 	writew(val, host->ioaddr + reg);
104 }
105 
106 static void tegra_sdhci_writel(struct sdhci_host *host, u32 val, int reg)
107 {
108 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
109 	struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
110 	const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
111 
112 	/* Seems like we're getting spurious timeout and crc errors, so
113 	 * disable signalling of them. In case of real errors software
114 	 * timers should take care of eventually detecting them.
115 	 */
116 	if (unlikely(reg == SDHCI_SIGNAL_ENABLE))
117 		val &= ~(SDHCI_INT_TIMEOUT|SDHCI_INT_CRC);
118 
119 	writel(val, host->ioaddr + reg);
120 
121 	if (unlikely((soc_data->nvquirks & NVQUIRK_ENABLE_BLOCK_GAP_DET) &&
122 			(reg == SDHCI_INT_ENABLE))) {
123 		/* Erratum: Must enable block gap interrupt detection */
124 		u8 gap_ctrl = readb(host->ioaddr + SDHCI_BLOCK_GAP_CONTROL);
125 		if (val & SDHCI_INT_CARD_INT)
126 			gap_ctrl |= 0x8;
127 		else
128 			gap_ctrl &= ~0x8;
129 		writeb(gap_ctrl, host->ioaddr + SDHCI_BLOCK_GAP_CONTROL);
130 	}
131 }
132 
133 static unsigned int tegra_sdhci_get_ro(struct sdhci_host *host)
134 {
135 	return mmc_gpio_get_ro(host->mmc);
136 }
137 
138 static void tegra_sdhci_reset(struct sdhci_host *host, u8 mask)
139 {
140 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
141 	struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
142 	const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
143 	u32 misc_ctrl, clk_ctrl;
144 
145 	sdhci_reset(host, mask);
146 
147 	if (!(mask & SDHCI_RESET_ALL))
148 		return;
149 
150 	misc_ctrl = sdhci_readl(host, SDHCI_TEGRA_VENDOR_MISC_CTRL);
151 	/* Erratum: Enable SDHCI spec v3.00 support */
152 	if (soc_data->nvquirks & NVQUIRK_ENABLE_SDHCI_SPEC_300)
153 		misc_ctrl |= SDHCI_MISC_CTRL_ENABLE_SDHCI_SPEC_300;
154 	/* Advertise UHS modes as supported by host */
155 	if (soc_data->nvquirks & NVQUIRK_ENABLE_SDR50)
156 		misc_ctrl |= SDHCI_MISC_CTRL_ENABLE_SDR50;
157 	else
158 		misc_ctrl &= ~SDHCI_MISC_CTRL_ENABLE_SDR50;
159 	if (soc_data->nvquirks & NVQUIRK_ENABLE_DDR50)
160 		misc_ctrl |= SDHCI_MISC_CTRL_ENABLE_DDR50;
161 	else
162 		misc_ctrl &= ~SDHCI_MISC_CTRL_ENABLE_DDR50;
163 	if (soc_data->nvquirks & NVQUIRK_ENABLE_SDR104)
164 		misc_ctrl |= SDHCI_MISC_CTRL_ENABLE_SDR104;
165 	else
166 		misc_ctrl &= ~SDHCI_MISC_CTRL_ENABLE_SDR104;
167 	sdhci_writel(host, misc_ctrl, SDHCI_TEGRA_VENDOR_MISC_CTRL);
168 
169 	clk_ctrl = sdhci_readl(host, SDHCI_TEGRA_VENDOR_CLOCK_CTRL);
170 	clk_ctrl &= ~SDHCI_CLOCK_CTRL_SPI_MODE_CLKEN_OVERRIDE;
171 	if (soc_data->nvquirks & SDHCI_MISC_CTRL_ENABLE_SDR50)
172 		clk_ctrl |= SDHCI_CLOCK_CTRL_SDR50_TUNING_OVERRIDE;
173 	sdhci_writel(host, clk_ctrl, SDHCI_TEGRA_VENDOR_CLOCK_CTRL);
174 
175 	if (soc_data->nvquirks & NVQUIRK_HAS_PADCALIB)
176 		tegra_host->pad_calib_required = true;
177 
178 	tegra_host->ddr_signaling = false;
179 }
180 
181 static void tegra_sdhci_set_bus_width(struct sdhci_host *host, int bus_width)
182 {
183 	u32 ctrl;
184 
185 	ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
186 	if ((host->mmc->caps & MMC_CAP_8_BIT_DATA) &&
187 	    (bus_width == MMC_BUS_WIDTH_8)) {
188 		ctrl &= ~SDHCI_CTRL_4BITBUS;
189 		ctrl |= SDHCI_CTRL_8BITBUS;
190 	} else {
191 		ctrl &= ~SDHCI_CTRL_8BITBUS;
192 		if (bus_width == MMC_BUS_WIDTH_4)
193 			ctrl |= SDHCI_CTRL_4BITBUS;
194 		else
195 			ctrl &= ~SDHCI_CTRL_4BITBUS;
196 	}
197 	sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
198 }
199 
200 static void tegra_sdhci_pad_autocalib(struct sdhci_host *host)
201 {
202 	u32 val;
203 
204 	mdelay(1);
205 
206 	val = sdhci_readl(host, SDHCI_TEGRA_AUTO_CAL_CONFIG);
207 	val |= SDHCI_AUTO_CAL_ENABLE | SDHCI_AUTO_CAL_START;
208 	sdhci_writel(host,val, SDHCI_TEGRA_AUTO_CAL_CONFIG);
209 }
210 
211 static void tegra_sdhci_set_clock(struct sdhci_host *host, unsigned int clock)
212 {
213 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
214 	struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
215 	unsigned long host_clk;
216 
217 	if (!clock)
218 		return sdhci_set_clock(host, clock);
219 
220 	host_clk = tegra_host->ddr_signaling ? clock * 2 : clock;
221 	clk_set_rate(pltfm_host->clk, host_clk);
222 	host->max_clk = clk_get_rate(pltfm_host->clk);
223 
224 	sdhci_set_clock(host, clock);
225 
226 	if (tegra_host->pad_calib_required) {
227 		tegra_sdhci_pad_autocalib(host);
228 		tegra_host->pad_calib_required = false;
229 	}
230 }
231 
232 static void tegra_sdhci_set_uhs_signaling(struct sdhci_host *host,
233 					  unsigned timing)
234 {
235 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
236 	struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
237 
238 	if (timing == MMC_TIMING_UHS_DDR50)
239 		tegra_host->ddr_signaling = true;
240 
241 	return sdhci_set_uhs_signaling(host, timing);
242 }
243 
244 static unsigned int tegra_sdhci_get_max_clock(struct sdhci_host *host)
245 {
246 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
247 
248 	/*
249 	 * DDR modes require the host to run at double the card frequency, so
250 	 * the maximum rate we can support is half of the module input clock.
251 	 */
252 	return clk_round_rate(pltfm_host->clk, UINT_MAX) / 2;
253 }
254 
255 static void tegra_sdhci_set_tap(struct sdhci_host *host, unsigned int tap)
256 {
257 	u32 reg;
258 
259 	reg = sdhci_readl(host, SDHCI_TEGRA_VENDOR_CLOCK_CTRL);
260 	reg &= ~SDHCI_CLOCK_CTRL_TAP_MASK;
261 	reg |= tap << SDHCI_CLOCK_CTRL_TAP_SHIFT;
262 	sdhci_writel(host, reg, SDHCI_TEGRA_VENDOR_CLOCK_CTRL);
263 }
264 
265 static int tegra_sdhci_execute_tuning(struct sdhci_host *host, u32 opcode)
266 {
267 	unsigned int min, max;
268 
269 	/*
270 	 * Start search for minimum tap value at 10, as smaller values are
271 	 * may wrongly be reported as working but fail at higher speeds,
272 	 * according to the TRM.
273 	 */
274 	min = 10;
275 	while (min < 255) {
276 		tegra_sdhci_set_tap(host, min);
277 		if (!mmc_send_tuning(host->mmc, opcode, NULL))
278 			break;
279 		min++;
280 	}
281 
282 	/* Find the maximum tap value that still passes. */
283 	max = min + 1;
284 	while (max < 255) {
285 		tegra_sdhci_set_tap(host, max);
286 		if (mmc_send_tuning(host->mmc, opcode, NULL)) {
287 			max--;
288 			break;
289 		}
290 		max++;
291 	}
292 
293 	/* The TRM states the ideal tap value is at 75% in the passing range. */
294 	tegra_sdhci_set_tap(host, min + ((max - min) * 3 / 4));
295 
296 	return mmc_send_tuning(host->mmc, opcode, NULL);
297 }
298 
299 static void tegra_sdhci_voltage_switch(struct sdhci_host *host)
300 {
301 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
302 	struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
303 	const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
304 
305 	if (soc_data->nvquirks & NVQUIRK_HAS_PADCALIB)
306 		tegra_host->pad_calib_required = true;
307 }
308 
309 static const struct sdhci_ops tegra_sdhci_ops = {
310 	.get_ro     = tegra_sdhci_get_ro,
311 	.read_w     = tegra_sdhci_readw,
312 	.write_l    = tegra_sdhci_writel,
313 	.set_clock  = tegra_sdhci_set_clock,
314 	.set_bus_width = tegra_sdhci_set_bus_width,
315 	.reset      = tegra_sdhci_reset,
316 	.platform_execute_tuning = tegra_sdhci_execute_tuning,
317 	.set_uhs_signaling = tegra_sdhci_set_uhs_signaling,
318 	.voltage_switch = tegra_sdhci_voltage_switch,
319 	.get_max_clock = tegra_sdhci_get_max_clock,
320 };
321 
322 static const struct sdhci_pltfm_data sdhci_tegra20_pdata = {
323 	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
324 		  SDHCI_QUIRK_SINGLE_POWER_WRITE |
325 		  SDHCI_QUIRK_NO_HISPD_BIT |
326 		  SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
327 		  SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
328 	.ops  = &tegra_sdhci_ops,
329 };
330 
331 static const struct sdhci_tegra_soc_data soc_data_tegra20 = {
332 	.pdata = &sdhci_tegra20_pdata,
333 	.nvquirks = NVQUIRK_FORCE_SDHCI_SPEC_200 |
334 		    NVQUIRK_ENABLE_BLOCK_GAP_DET,
335 };
336 
337 static const struct sdhci_pltfm_data sdhci_tegra30_pdata = {
338 	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
339 		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
340 		  SDHCI_QUIRK_SINGLE_POWER_WRITE |
341 		  SDHCI_QUIRK_NO_HISPD_BIT |
342 		  SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
343 		  SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
344 	.quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
345 	.ops  = &tegra_sdhci_ops,
346 };
347 
348 static const struct sdhci_tegra_soc_data soc_data_tegra30 = {
349 	.pdata = &sdhci_tegra30_pdata,
350 	.nvquirks = NVQUIRK_ENABLE_SDHCI_SPEC_300 |
351 		    NVQUIRK_ENABLE_SDR50 |
352 		    NVQUIRK_ENABLE_SDR104 |
353 		    NVQUIRK_HAS_PADCALIB,
354 };
355 
356 static const struct sdhci_ops tegra114_sdhci_ops = {
357 	.get_ro     = tegra_sdhci_get_ro,
358 	.read_w     = tegra_sdhci_readw,
359 	.write_w    = tegra_sdhci_writew,
360 	.write_l    = tegra_sdhci_writel,
361 	.set_clock  = tegra_sdhci_set_clock,
362 	.set_bus_width = tegra_sdhci_set_bus_width,
363 	.reset      = tegra_sdhci_reset,
364 	.platform_execute_tuning = tegra_sdhci_execute_tuning,
365 	.set_uhs_signaling = tegra_sdhci_set_uhs_signaling,
366 	.voltage_switch = tegra_sdhci_voltage_switch,
367 	.get_max_clock = tegra_sdhci_get_max_clock,
368 };
369 
370 static const struct sdhci_pltfm_data sdhci_tegra114_pdata = {
371 	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
372 		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
373 		  SDHCI_QUIRK_SINGLE_POWER_WRITE |
374 		  SDHCI_QUIRK_NO_HISPD_BIT |
375 		  SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
376 		  SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
377 	.quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
378 	.ops  = &tegra114_sdhci_ops,
379 };
380 
381 static const struct sdhci_tegra_soc_data soc_data_tegra114 = {
382 	.pdata = &sdhci_tegra114_pdata,
383 };
384 
385 static const struct sdhci_pltfm_data sdhci_tegra210_pdata = {
386 	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
387 		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
388 		  SDHCI_QUIRK_SINGLE_POWER_WRITE |
389 		  SDHCI_QUIRK_NO_HISPD_BIT |
390 		  SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
391 		  SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
392 	.quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
393 	.ops  = &tegra114_sdhci_ops,
394 };
395 
396 static const struct sdhci_tegra_soc_data soc_data_tegra210 = {
397 	.pdata = &sdhci_tegra210_pdata,
398 };
399 
400 static const struct of_device_id sdhci_tegra_dt_match[] = {
401 	{ .compatible = "nvidia,tegra210-sdhci", .data = &soc_data_tegra210 },
402 	{ .compatible = "nvidia,tegra124-sdhci", .data = &soc_data_tegra114 },
403 	{ .compatible = "nvidia,tegra114-sdhci", .data = &soc_data_tegra114 },
404 	{ .compatible = "nvidia,tegra30-sdhci", .data = &soc_data_tegra30 },
405 	{ .compatible = "nvidia,tegra20-sdhci", .data = &soc_data_tegra20 },
406 	{}
407 };
408 MODULE_DEVICE_TABLE(of, sdhci_tegra_dt_match);
409 
410 static int sdhci_tegra_probe(struct platform_device *pdev)
411 {
412 	const struct of_device_id *match;
413 	const struct sdhci_tegra_soc_data *soc_data;
414 	struct sdhci_host *host;
415 	struct sdhci_pltfm_host *pltfm_host;
416 	struct sdhci_tegra *tegra_host;
417 	struct clk *clk;
418 	int rc;
419 
420 	match = of_match_device(sdhci_tegra_dt_match, &pdev->dev);
421 	if (!match)
422 		return -EINVAL;
423 	soc_data = match->data;
424 
425 	host = sdhci_pltfm_init(pdev, soc_data->pdata, sizeof(*tegra_host));
426 	if (IS_ERR(host))
427 		return PTR_ERR(host);
428 	pltfm_host = sdhci_priv(host);
429 
430 	tegra_host = sdhci_pltfm_priv(pltfm_host);
431 	tegra_host->ddr_signaling = false;
432 	tegra_host->pad_calib_required = false;
433 	tegra_host->soc_data = soc_data;
434 
435 	rc = mmc_of_parse(host->mmc);
436 	if (rc)
437 		goto err_parse_dt;
438 
439 	if (tegra_host->soc_data->nvquirks & NVQUIRK_ENABLE_DDR50)
440 		host->mmc->caps |= MMC_CAP_1_8V_DDR;
441 
442 	tegra_host->power_gpio = devm_gpiod_get_optional(&pdev->dev, "power",
443 							 GPIOD_OUT_HIGH);
444 	if (IS_ERR(tegra_host->power_gpio)) {
445 		rc = PTR_ERR(tegra_host->power_gpio);
446 		goto err_power_req;
447 	}
448 
449 	clk = devm_clk_get(mmc_dev(host->mmc), NULL);
450 	if (IS_ERR(clk)) {
451 		dev_err(mmc_dev(host->mmc), "clk err\n");
452 		rc = PTR_ERR(clk);
453 		goto err_clk_get;
454 	}
455 	clk_prepare_enable(clk);
456 	pltfm_host->clk = clk;
457 
458 	rc = sdhci_add_host(host);
459 	if (rc)
460 		goto err_add_host;
461 
462 	return 0;
463 
464 err_add_host:
465 	clk_disable_unprepare(pltfm_host->clk);
466 err_clk_get:
467 err_power_req:
468 err_parse_dt:
469 	sdhci_pltfm_free(pdev);
470 	return rc;
471 }
472 
473 static struct platform_driver sdhci_tegra_driver = {
474 	.driver		= {
475 		.name	= "sdhci-tegra",
476 		.of_match_table = sdhci_tegra_dt_match,
477 		.pm	= SDHCI_PLTFM_PMOPS,
478 	},
479 	.probe		= sdhci_tegra_probe,
480 	.remove		= sdhci_pltfm_unregister,
481 };
482 
483 module_platform_driver(sdhci_tegra_driver);
484 
485 MODULE_DESCRIPTION("SDHCI driver for Tegra");
486 MODULE_AUTHOR("Google, Inc.");
487 MODULE_LICENSE("GPL v2");
488