xref: /openbmc/linux/drivers/mmc/host/sdhci-tegra.c (revision 97da55fc)
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/err.h>
16 #include <linux/module.h>
17 #include <linux/init.h>
18 #include <linux/platform_device.h>
19 #include <linux/clk.h>
20 #include <linux/io.h>
21 #include <linux/of.h>
22 #include <linux/of_device.h>
23 #include <linux/of_gpio.h>
24 #include <linux/gpio.h>
25 #include <linux/mmc/card.h>
26 #include <linux/mmc/host.h>
27 
28 #include <asm/gpio.h>
29 
30 #include "sdhci-pltfm.h"
31 
32 /* Tegra SDHOST controller vendor register definitions */
33 #define SDHCI_TEGRA_VENDOR_MISC_CTRL		0x120
34 #define SDHCI_MISC_CTRL_ENABLE_SDHCI_SPEC_300	0x20
35 
36 #define NVQUIRK_FORCE_SDHCI_SPEC_200	BIT(0)
37 #define NVQUIRK_ENABLE_BLOCK_GAP_DET	BIT(1)
38 #define NVQUIRK_ENABLE_SDHCI_SPEC_300	BIT(2)
39 
40 struct sdhci_tegra_soc_data {
41 	struct sdhci_pltfm_data *pdata;
42 	u32 nvquirks;
43 };
44 
45 struct sdhci_tegra {
46 	const struct sdhci_tegra_soc_data *soc_data;
47 	int cd_gpio;
48 	int wp_gpio;
49 	int power_gpio;
50 	int is_8bit;
51 };
52 
53 static u32 tegra_sdhci_readl(struct sdhci_host *host, int reg)
54 {
55 	u32 val;
56 
57 	if (unlikely(reg == SDHCI_PRESENT_STATE)) {
58 		/* Use wp_gpio here instead? */
59 		val = readl(host->ioaddr + reg);
60 		return val | SDHCI_WRITE_PROTECT;
61 	}
62 
63 	return readl(host->ioaddr + reg);
64 }
65 
66 static u16 tegra_sdhci_readw(struct sdhci_host *host, int reg)
67 {
68 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
69 	struct sdhci_tegra *tegra_host = pltfm_host->priv;
70 	const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
71 
72 	if (unlikely((soc_data->nvquirks & NVQUIRK_FORCE_SDHCI_SPEC_200) &&
73 			(reg == SDHCI_HOST_VERSION))) {
74 		/* Erratum: Version register is invalid in HW. */
75 		return SDHCI_SPEC_200;
76 	}
77 
78 	return readw(host->ioaddr + reg);
79 }
80 
81 static void tegra_sdhci_writel(struct sdhci_host *host, u32 val, int reg)
82 {
83 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
84 	struct sdhci_tegra *tegra_host = pltfm_host->priv;
85 	const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
86 
87 	/* Seems like we're getting spurious timeout and crc errors, so
88 	 * disable signalling of them. In case of real errors software
89 	 * timers should take care of eventually detecting them.
90 	 */
91 	if (unlikely(reg == SDHCI_SIGNAL_ENABLE))
92 		val &= ~(SDHCI_INT_TIMEOUT|SDHCI_INT_CRC);
93 
94 	writel(val, host->ioaddr + reg);
95 
96 	if (unlikely((soc_data->nvquirks & NVQUIRK_ENABLE_BLOCK_GAP_DET) &&
97 			(reg == SDHCI_INT_ENABLE))) {
98 		/* Erratum: Must enable block gap interrupt detection */
99 		u8 gap_ctrl = readb(host->ioaddr + SDHCI_BLOCK_GAP_CONTROL);
100 		if (val & SDHCI_INT_CARD_INT)
101 			gap_ctrl |= 0x8;
102 		else
103 			gap_ctrl &= ~0x8;
104 		writeb(gap_ctrl, host->ioaddr + SDHCI_BLOCK_GAP_CONTROL);
105 	}
106 }
107 
108 static unsigned int tegra_sdhci_get_ro(struct sdhci_host *host)
109 {
110 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
111 	struct sdhci_tegra *tegra_host = pltfm_host->priv;
112 
113 	if (!gpio_is_valid(tegra_host->wp_gpio))
114 		return -1;
115 
116 	return gpio_get_value(tegra_host->wp_gpio);
117 }
118 
119 static irqreturn_t carddetect_irq(int irq, void *data)
120 {
121 	struct sdhci_host *sdhost = (struct sdhci_host *)data;
122 
123 	tasklet_schedule(&sdhost->card_tasklet);
124 	return IRQ_HANDLED;
125 };
126 
127 static void tegra_sdhci_reset_exit(struct sdhci_host *host, u8 mask)
128 {
129 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
130 	struct sdhci_tegra *tegra_host = pltfm_host->priv;
131 	const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
132 
133 	if (!(mask & SDHCI_RESET_ALL))
134 		return;
135 
136 	/* Erratum: Enable SDHCI spec v3.00 support */
137 	if (soc_data->nvquirks & NVQUIRK_ENABLE_SDHCI_SPEC_300) {
138 		u32 misc_ctrl;
139 
140 		misc_ctrl = sdhci_readb(host, SDHCI_TEGRA_VENDOR_MISC_CTRL);
141 		misc_ctrl |= SDHCI_MISC_CTRL_ENABLE_SDHCI_SPEC_300;
142 		sdhci_writeb(host, misc_ctrl, SDHCI_TEGRA_VENDOR_MISC_CTRL);
143 	}
144 }
145 
146 static int tegra_sdhci_buswidth(struct sdhci_host *host, int bus_width)
147 {
148 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
149 	struct sdhci_tegra *tegra_host = pltfm_host->priv;
150 	u32 ctrl;
151 
152 	ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
153 	if (tegra_host->is_8bit && bus_width == MMC_BUS_WIDTH_8) {
154 		ctrl &= ~SDHCI_CTRL_4BITBUS;
155 		ctrl |= SDHCI_CTRL_8BITBUS;
156 	} else {
157 		ctrl &= ~SDHCI_CTRL_8BITBUS;
158 		if (bus_width == MMC_BUS_WIDTH_4)
159 			ctrl |= SDHCI_CTRL_4BITBUS;
160 		else
161 			ctrl &= ~SDHCI_CTRL_4BITBUS;
162 	}
163 	sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
164 	return 0;
165 }
166 
167 static struct sdhci_ops tegra_sdhci_ops = {
168 	.get_ro     = tegra_sdhci_get_ro,
169 	.read_l     = tegra_sdhci_readl,
170 	.read_w     = tegra_sdhci_readw,
171 	.write_l    = tegra_sdhci_writel,
172 	.platform_bus_width = tegra_sdhci_buswidth,
173 	.platform_reset_exit = tegra_sdhci_reset_exit,
174 };
175 
176 #ifdef CONFIG_ARCH_TEGRA_2x_SOC
177 static struct sdhci_pltfm_data sdhci_tegra20_pdata = {
178 	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
179 		  SDHCI_QUIRK_SINGLE_POWER_WRITE |
180 		  SDHCI_QUIRK_NO_HISPD_BIT |
181 		  SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC,
182 	.ops  = &tegra_sdhci_ops,
183 };
184 
185 static struct sdhci_tegra_soc_data soc_data_tegra20 = {
186 	.pdata = &sdhci_tegra20_pdata,
187 	.nvquirks = NVQUIRK_FORCE_SDHCI_SPEC_200 |
188 		    NVQUIRK_ENABLE_BLOCK_GAP_DET,
189 };
190 #endif
191 
192 #ifdef CONFIG_ARCH_TEGRA_3x_SOC
193 static struct sdhci_pltfm_data sdhci_tegra30_pdata = {
194 	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
195 		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
196 		  SDHCI_QUIRK_SINGLE_POWER_WRITE |
197 		  SDHCI_QUIRK_NO_HISPD_BIT |
198 		  SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC,
199 	.ops  = &tegra_sdhci_ops,
200 };
201 
202 static struct sdhci_tegra_soc_data soc_data_tegra30 = {
203 	.pdata = &sdhci_tegra30_pdata,
204 	.nvquirks = NVQUIRK_ENABLE_SDHCI_SPEC_300,
205 };
206 #endif
207 
208 static const struct of_device_id sdhci_tegra_dt_match[] = {
209 #ifdef CONFIG_ARCH_TEGRA_3x_SOC
210 	{ .compatible = "nvidia,tegra30-sdhci", .data = &soc_data_tegra30 },
211 #endif
212 #ifdef CONFIG_ARCH_TEGRA_2x_SOC
213 	{ .compatible = "nvidia,tegra20-sdhci", .data = &soc_data_tegra20 },
214 #endif
215 	{}
216 };
217 MODULE_DEVICE_TABLE(of, sdhci_dt_ids);
218 
219 static void sdhci_tegra_parse_dt(struct device *dev,
220 					struct sdhci_tegra *tegra_host)
221 {
222 	struct device_node *np = dev->of_node;
223 	u32 bus_width;
224 
225 	tegra_host->cd_gpio = of_get_named_gpio(np, "cd-gpios", 0);
226 	tegra_host->wp_gpio = of_get_named_gpio(np, "wp-gpios", 0);
227 	tegra_host->power_gpio = of_get_named_gpio(np, "power-gpios", 0);
228 
229 	if (of_property_read_u32(np, "bus-width", &bus_width) == 0 &&
230 	    bus_width == 8)
231 		tegra_host->is_8bit = 1;
232 }
233 
234 static int sdhci_tegra_probe(struct platform_device *pdev)
235 {
236 	const struct of_device_id *match;
237 	const struct sdhci_tegra_soc_data *soc_data;
238 	struct sdhci_host *host;
239 	struct sdhci_pltfm_host *pltfm_host;
240 	struct sdhci_tegra *tegra_host;
241 	struct clk *clk;
242 	int rc;
243 
244 	match = of_match_device(sdhci_tegra_dt_match, &pdev->dev);
245 	if (!match)
246 		return -EINVAL;
247 	soc_data = match->data;
248 
249 	host = sdhci_pltfm_init(pdev, soc_data->pdata);
250 	if (IS_ERR(host))
251 		return PTR_ERR(host);
252 	pltfm_host = sdhci_priv(host);
253 
254 	tegra_host = devm_kzalloc(&pdev->dev, sizeof(*tegra_host), GFP_KERNEL);
255 	if (!tegra_host) {
256 		dev_err(mmc_dev(host->mmc), "failed to allocate tegra_host\n");
257 		rc = -ENOMEM;
258 		goto err_alloc_tegra_host;
259 	}
260 	tegra_host->soc_data = soc_data;
261 	pltfm_host->priv = tegra_host;
262 
263 	sdhci_tegra_parse_dt(&pdev->dev, tegra_host);
264 
265 	if (gpio_is_valid(tegra_host->power_gpio)) {
266 		rc = gpio_request(tegra_host->power_gpio, "sdhci_power");
267 		if (rc) {
268 			dev_err(mmc_dev(host->mmc),
269 				"failed to allocate power gpio\n");
270 			goto err_power_req;
271 		}
272 		gpio_direction_output(tegra_host->power_gpio, 1);
273 	}
274 
275 	if (gpio_is_valid(tegra_host->cd_gpio)) {
276 		rc = gpio_request(tegra_host->cd_gpio, "sdhci_cd");
277 		if (rc) {
278 			dev_err(mmc_dev(host->mmc),
279 				"failed to allocate cd gpio\n");
280 			goto err_cd_req;
281 		}
282 		gpio_direction_input(tegra_host->cd_gpio);
283 
284 		rc = request_irq(gpio_to_irq(tegra_host->cd_gpio),
285 				 carddetect_irq,
286 				 IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
287 				 mmc_hostname(host->mmc), host);
288 
289 		if (rc)	{
290 			dev_err(mmc_dev(host->mmc), "request irq error\n");
291 			goto err_cd_irq_req;
292 		}
293 
294 	}
295 
296 	if (gpio_is_valid(tegra_host->wp_gpio)) {
297 		rc = gpio_request(tegra_host->wp_gpio, "sdhci_wp");
298 		if (rc) {
299 			dev_err(mmc_dev(host->mmc),
300 				"failed to allocate wp gpio\n");
301 			goto err_wp_req;
302 		}
303 		gpio_direction_input(tegra_host->wp_gpio);
304 	}
305 
306 	clk = clk_get(mmc_dev(host->mmc), NULL);
307 	if (IS_ERR(clk)) {
308 		dev_err(mmc_dev(host->mmc), "clk err\n");
309 		rc = PTR_ERR(clk);
310 		goto err_clk_get;
311 	}
312 	clk_prepare_enable(clk);
313 	pltfm_host->clk = clk;
314 
315 	if (tegra_host->is_8bit)
316 		host->mmc->caps |= MMC_CAP_8_BIT_DATA;
317 
318 	rc = sdhci_add_host(host);
319 	if (rc)
320 		goto err_add_host;
321 
322 	return 0;
323 
324 err_add_host:
325 	clk_disable_unprepare(pltfm_host->clk);
326 	clk_put(pltfm_host->clk);
327 err_clk_get:
328 	if (gpio_is_valid(tegra_host->wp_gpio))
329 		gpio_free(tegra_host->wp_gpio);
330 err_wp_req:
331 	if (gpio_is_valid(tegra_host->cd_gpio))
332 		free_irq(gpio_to_irq(tegra_host->cd_gpio), host);
333 err_cd_irq_req:
334 	if (gpio_is_valid(tegra_host->cd_gpio))
335 		gpio_free(tegra_host->cd_gpio);
336 err_cd_req:
337 	if (gpio_is_valid(tegra_host->power_gpio))
338 		gpio_free(tegra_host->power_gpio);
339 err_power_req:
340 err_alloc_tegra_host:
341 	sdhci_pltfm_free(pdev);
342 	return rc;
343 }
344 
345 static int sdhci_tegra_remove(struct platform_device *pdev)
346 {
347 	struct sdhci_host *host = platform_get_drvdata(pdev);
348 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
349 	struct sdhci_tegra *tegra_host = pltfm_host->priv;
350 	int dead = (readl(host->ioaddr + SDHCI_INT_STATUS) == 0xffffffff);
351 
352 	sdhci_remove_host(host, dead);
353 
354 	if (gpio_is_valid(tegra_host->wp_gpio))
355 		gpio_free(tegra_host->wp_gpio);
356 
357 	if (gpio_is_valid(tegra_host->cd_gpio)) {
358 		free_irq(gpio_to_irq(tegra_host->cd_gpio), host);
359 		gpio_free(tegra_host->cd_gpio);
360 	}
361 
362 	if (gpio_is_valid(tegra_host->power_gpio))
363 		gpio_free(tegra_host->power_gpio);
364 
365 	clk_disable_unprepare(pltfm_host->clk);
366 	clk_put(pltfm_host->clk);
367 
368 	sdhci_pltfm_free(pdev);
369 
370 	return 0;
371 }
372 
373 static struct platform_driver sdhci_tegra_driver = {
374 	.driver		= {
375 		.name	= "sdhci-tegra",
376 		.owner	= THIS_MODULE,
377 		.of_match_table = sdhci_tegra_dt_match,
378 		.pm	= SDHCI_PLTFM_PMOPS,
379 	},
380 	.probe		= sdhci_tegra_probe,
381 	.remove		= sdhci_tegra_remove,
382 };
383 
384 module_platform_driver(sdhci_tegra_driver);
385 
386 MODULE_DESCRIPTION("SDHCI driver for Tegra");
387 MODULE_AUTHOR("Google, Inc.");
388 MODULE_LICENSE("GPL v2");
389