xref: /openbmc/linux/drivers/mmc/host/sdhci-tegra.c (revision 5104d265)
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 #include <linux/mmc/slot-gpio.h>
28 
29 #include <asm/gpio.h>
30 
31 #include "sdhci-pltfm.h"
32 
33 /* Tegra SDHOST controller vendor register definitions */
34 #define SDHCI_TEGRA_VENDOR_MISC_CTRL		0x120
35 #define SDHCI_MISC_CTRL_ENABLE_SDHCI_SPEC_300	0x20
36 
37 #define NVQUIRK_FORCE_SDHCI_SPEC_200	BIT(0)
38 #define NVQUIRK_ENABLE_BLOCK_GAP_DET	BIT(1)
39 #define NVQUIRK_ENABLE_SDHCI_SPEC_300	BIT(2)
40 
41 struct sdhci_tegra_soc_data {
42 	const struct sdhci_pltfm_data *pdata;
43 	u32 nvquirks;
44 };
45 
46 struct sdhci_tegra {
47 	const struct sdhci_tegra_soc_data *soc_data;
48 	int power_gpio;
49 };
50 
51 static u32 tegra_sdhci_readl(struct sdhci_host *host, int reg)
52 {
53 	u32 val;
54 
55 	if (unlikely(reg == SDHCI_PRESENT_STATE)) {
56 		/* Use wp_gpio here instead? */
57 		val = readl(host->ioaddr + reg);
58 		return val | SDHCI_WRITE_PROTECT;
59 	}
60 
61 	return readl(host->ioaddr + reg);
62 }
63 
64 static u16 tegra_sdhci_readw(struct sdhci_host *host, int reg)
65 {
66 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
67 	struct sdhci_tegra *tegra_host = pltfm_host->priv;
68 	const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
69 
70 	if (unlikely((soc_data->nvquirks & NVQUIRK_FORCE_SDHCI_SPEC_200) &&
71 			(reg == SDHCI_HOST_VERSION))) {
72 		/* Erratum: Version register is invalid in HW. */
73 		return SDHCI_SPEC_200;
74 	}
75 
76 	return readw(host->ioaddr + reg);
77 }
78 
79 static void tegra_sdhci_writel(struct sdhci_host *host, u32 val, int reg)
80 {
81 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
82 	struct sdhci_tegra *tegra_host = pltfm_host->priv;
83 	const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
84 
85 	/* Seems like we're getting spurious timeout and crc errors, so
86 	 * disable signalling of them. In case of real errors software
87 	 * timers should take care of eventually detecting them.
88 	 */
89 	if (unlikely(reg == SDHCI_SIGNAL_ENABLE))
90 		val &= ~(SDHCI_INT_TIMEOUT|SDHCI_INT_CRC);
91 
92 	writel(val, host->ioaddr + reg);
93 
94 	if (unlikely((soc_data->nvquirks & NVQUIRK_ENABLE_BLOCK_GAP_DET) &&
95 			(reg == SDHCI_INT_ENABLE))) {
96 		/* Erratum: Must enable block gap interrupt detection */
97 		u8 gap_ctrl = readb(host->ioaddr + SDHCI_BLOCK_GAP_CONTROL);
98 		if (val & SDHCI_INT_CARD_INT)
99 			gap_ctrl |= 0x8;
100 		else
101 			gap_ctrl &= ~0x8;
102 		writeb(gap_ctrl, host->ioaddr + SDHCI_BLOCK_GAP_CONTROL);
103 	}
104 }
105 
106 static unsigned int tegra_sdhci_get_ro(struct sdhci_host *host)
107 {
108 	return mmc_gpio_get_ro(host->mmc);
109 }
110 
111 static void tegra_sdhci_reset_exit(struct sdhci_host *host, u8 mask)
112 {
113 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
114 	struct sdhci_tegra *tegra_host = pltfm_host->priv;
115 	const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
116 
117 	if (!(mask & SDHCI_RESET_ALL))
118 		return;
119 
120 	/* Erratum: Enable SDHCI spec v3.00 support */
121 	if (soc_data->nvquirks & NVQUIRK_ENABLE_SDHCI_SPEC_300) {
122 		u32 misc_ctrl;
123 
124 		misc_ctrl = sdhci_readb(host, SDHCI_TEGRA_VENDOR_MISC_CTRL);
125 		misc_ctrl |= SDHCI_MISC_CTRL_ENABLE_SDHCI_SPEC_300;
126 		sdhci_writeb(host, misc_ctrl, SDHCI_TEGRA_VENDOR_MISC_CTRL);
127 	}
128 }
129 
130 static int tegra_sdhci_buswidth(struct sdhci_host *host, int bus_width)
131 {
132 	u32 ctrl;
133 
134 	ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
135 	if ((host->mmc->caps & MMC_CAP_8_BIT_DATA) &&
136 	    (bus_width == MMC_BUS_WIDTH_8)) {
137 		ctrl &= ~SDHCI_CTRL_4BITBUS;
138 		ctrl |= SDHCI_CTRL_8BITBUS;
139 	} else {
140 		ctrl &= ~SDHCI_CTRL_8BITBUS;
141 		if (bus_width == MMC_BUS_WIDTH_4)
142 			ctrl |= SDHCI_CTRL_4BITBUS;
143 		else
144 			ctrl &= ~SDHCI_CTRL_4BITBUS;
145 	}
146 	sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
147 	return 0;
148 }
149 
150 static const struct sdhci_ops tegra_sdhci_ops = {
151 	.get_ro     = tegra_sdhci_get_ro,
152 	.read_l     = tegra_sdhci_readl,
153 	.read_w     = tegra_sdhci_readw,
154 	.write_l    = tegra_sdhci_writel,
155 	.platform_bus_width = tegra_sdhci_buswidth,
156 	.platform_reset_exit = tegra_sdhci_reset_exit,
157 };
158 
159 static const struct sdhci_pltfm_data sdhci_tegra20_pdata = {
160 	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
161 		  SDHCI_QUIRK_SINGLE_POWER_WRITE |
162 		  SDHCI_QUIRK_NO_HISPD_BIT |
163 		  SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC,
164 	.ops  = &tegra_sdhci_ops,
165 };
166 
167 static struct sdhci_tegra_soc_data soc_data_tegra20 = {
168 	.pdata = &sdhci_tegra20_pdata,
169 	.nvquirks = NVQUIRK_FORCE_SDHCI_SPEC_200 |
170 		    NVQUIRK_ENABLE_BLOCK_GAP_DET,
171 };
172 
173 static const struct sdhci_pltfm_data sdhci_tegra30_pdata = {
174 	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
175 		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
176 		  SDHCI_QUIRK_SINGLE_POWER_WRITE |
177 		  SDHCI_QUIRK_NO_HISPD_BIT |
178 		  SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC,
179 	.ops  = &tegra_sdhci_ops,
180 };
181 
182 static struct sdhci_tegra_soc_data soc_data_tegra30 = {
183 	.pdata = &sdhci_tegra30_pdata,
184 	.nvquirks = NVQUIRK_ENABLE_SDHCI_SPEC_300,
185 };
186 
187 static const struct sdhci_pltfm_data sdhci_tegra114_pdata = {
188 	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
189 		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
190 		  SDHCI_QUIRK_SINGLE_POWER_WRITE |
191 		  SDHCI_QUIRK_NO_HISPD_BIT |
192 		  SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC,
193 	.ops  = &tegra_sdhci_ops,
194 };
195 
196 static struct sdhci_tegra_soc_data soc_data_tegra114 = {
197 	.pdata = &sdhci_tegra114_pdata,
198 };
199 
200 static const struct of_device_id sdhci_tegra_dt_match[] = {
201 	{ .compatible = "nvidia,tegra114-sdhci", .data = &soc_data_tegra114 },
202 	{ .compatible = "nvidia,tegra30-sdhci", .data = &soc_data_tegra30 },
203 	{ .compatible = "nvidia,tegra20-sdhci", .data = &soc_data_tegra20 },
204 	{}
205 };
206 MODULE_DEVICE_TABLE(of, sdhci_tegra_dt_match);
207 
208 static int sdhci_tegra_parse_dt(struct device *dev)
209 {
210 	struct device_node *np = dev->of_node;
211 	struct sdhci_host *host = dev_get_drvdata(dev);
212 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
213 	struct sdhci_tegra *tegra_host = pltfm_host->priv;
214 
215 	tegra_host->power_gpio = of_get_named_gpio(np, "power-gpios", 0);
216 	return mmc_of_parse(host->mmc);
217 }
218 
219 static int sdhci_tegra_probe(struct platform_device *pdev)
220 {
221 	const struct of_device_id *match;
222 	const struct sdhci_tegra_soc_data *soc_data;
223 	struct sdhci_host *host;
224 	struct sdhci_pltfm_host *pltfm_host;
225 	struct sdhci_tegra *tegra_host;
226 	struct clk *clk;
227 	int rc;
228 
229 	match = of_match_device(sdhci_tegra_dt_match, &pdev->dev);
230 	if (!match)
231 		return -EINVAL;
232 	soc_data = match->data;
233 
234 	host = sdhci_pltfm_init(pdev, soc_data->pdata, 0);
235 	if (IS_ERR(host))
236 		return PTR_ERR(host);
237 	pltfm_host = sdhci_priv(host);
238 
239 	tegra_host = devm_kzalloc(&pdev->dev, sizeof(*tegra_host), GFP_KERNEL);
240 	if (!tegra_host) {
241 		dev_err(mmc_dev(host->mmc), "failed to allocate tegra_host\n");
242 		rc = -ENOMEM;
243 		goto err_alloc_tegra_host;
244 	}
245 	tegra_host->soc_data = soc_data;
246 	pltfm_host->priv = tegra_host;
247 
248 	rc = sdhci_tegra_parse_dt(&pdev->dev);
249 	if (rc)
250 		goto err_parse_dt;
251 
252 	if (gpio_is_valid(tegra_host->power_gpio)) {
253 		rc = gpio_request(tegra_host->power_gpio, "sdhci_power");
254 		if (rc) {
255 			dev_err(mmc_dev(host->mmc),
256 				"failed to allocate power gpio\n");
257 			goto err_power_req;
258 		}
259 		gpio_direction_output(tegra_host->power_gpio, 1);
260 	}
261 
262 	clk = clk_get(mmc_dev(host->mmc), NULL);
263 	if (IS_ERR(clk)) {
264 		dev_err(mmc_dev(host->mmc), "clk err\n");
265 		rc = PTR_ERR(clk);
266 		goto err_clk_get;
267 	}
268 	clk_prepare_enable(clk);
269 	pltfm_host->clk = clk;
270 
271 	rc = sdhci_add_host(host);
272 	if (rc)
273 		goto err_add_host;
274 
275 	return 0;
276 
277 err_add_host:
278 	clk_disable_unprepare(pltfm_host->clk);
279 	clk_put(pltfm_host->clk);
280 err_clk_get:
281 	if (gpio_is_valid(tegra_host->power_gpio))
282 		gpio_free(tegra_host->power_gpio);
283 err_power_req:
284 err_parse_dt:
285 err_alloc_tegra_host:
286 	sdhci_pltfm_free(pdev);
287 	return rc;
288 }
289 
290 static int sdhci_tegra_remove(struct platform_device *pdev)
291 {
292 	struct sdhci_host *host = platform_get_drvdata(pdev);
293 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
294 	struct sdhci_tegra *tegra_host = pltfm_host->priv;
295 	int dead = (readl(host->ioaddr + SDHCI_INT_STATUS) == 0xffffffff);
296 
297 	sdhci_remove_host(host, dead);
298 
299 	if (gpio_is_valid(tegra_host->power_gpio))
300 		gpio_free(tegra_host->power_gpio);
301 
302 	clk_disable_unprepare(pltfm_host->clk);
303 	clk_put(pltfm_host->clk);
304 
305 	sdhci_pltfm_free(pdev);
306 
307 	return 0;
308 }
309 
310 static struct platform_driver sdhci_tegra_driver = {
311 	.driver		= {
312 		.name	= "sdhci-tegra",
313 		.owner	= THIS_MODULE,
314 		.of_match_table = sdhci_tegra_dt_match,
315 		.pm	= SDHCI_PLTFM_PMOPS,
316 	},
317 	.probe		= sdhci_tegra_probe,
318 	.remove		= sdhci_tegra_remove,
319 };
320 
321 module_platform_driver(sdhci_tegra_driver);
322 
323 MODULE_DESCRIPTION("SDHCI driver for Tegra");
324 MODULE_AUTHOR("Google, Inc.");
325 MODULE_LICENSE("GPL v2");
326