xref: /openbmc/linux/drivers/mmc/host/sdhci-pxav2.c (revision 8440bb9b)
1 /*
2  * Copyright (C) 2010 Marvell International Ltd.
3  *		Zhangfei Gao <zhangfei.gao@marvell.com>
4  *		Kevin Wang <dwang4@marvell.com>
5  *		Jun Nie <njun@marvell.com>
6  *		Qiming Wu <wuqm@marvell.com>
7  *		Philip Rakity <prakity@marvell.com>
8  *
9  * This software is licensed under the terms of the GNU General Public
10  * License version 2, as published by the Free Software Foundation, and
11  * may be copied, distributed, and modified under those terms.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  */
19 
20 #include <linux/err.h>
21 #include <linux/init.h>
22 #include <linux/platform_device.h>
23 #include <linux/clk.h>
24 #include <linux/module.h>
25 #include <linux/io.h>
26 #include <linux/mmc/card.h>
27 #include <linux/mmc/host.h>
28 #include <linux/platform_data/pxa_sdhci.h>
29 #include <linux/slab.h>
30 #include <linux/of.h>
31 #include <linux/of_device.h>
32 
33 #include "sdhci.h"
34 #include "sdhci-pltfm.h"
35 
36 #define SD_FIFO_PARAM		0xe0
37 #define DIS_PAD_SD_CLK_GATE	0x0400 /* Turn on/off Dynamic SD Clock Gating */
38 #define CLK_GATE_ON		0x0200 /* Disable/enable Clock Gate */
39 #define CLK_GATE_CTL		0x0100 /* Clock Gate Control */
40 #define CLK_GATE_SETTING_BITS	(DIS_PAD_SD_CLK_GATE | \
41 		CLK_GATE_ON | CLK_GATE_CTL)
42 
43 #define SD_CLOCK_BURST_SIZE_SETUP	0xe6
44 #define SDCLK_SEL_SHIFT		8
45 #define SDCLK_SEL_MASK		0x3
46 #define SDCLK_DELAY_SHIFT	10
47 #define SDCLK_DELAY_MASK	0x3c
48 
49 #define SD_CE_ATA_2		0xea
50 #define MMC_CARD		0x1000
51 #define MMC_WIDTH		0x0100
52 
53 static void pxav2_reset(struct sdhci_host *host, u8 mask)
54 {
55 	struct platform_device *pdev = to_platform_device(mmc_dev(host->mmc));
56 	struct sdhci_pxa_platdata *pdata = pdev->dev.platform_data;
57 
58 	sdhci_reset(host, mask);
59 
60 	if (mask == SDHCI_RESET_ALL) {
61 		u16 tmp = 0;
62 
63 		/*
64 		 * tune timing of read data/command when crc error happen
65 		 * no performance impact
66 		 */
67 		if (pdata && pdata->clk_delay_sel == 1) {
68 			tmp = readw(host->ioaddr + SD_CLOCK_BURST_SIZE_SETUP);
69 
70 			tmp &= ~(SDCLK_DELAY_MASK << SDCLK_DELAY_SHIFT);
71 			tmp |= (pdata->clk_delay_cycles & SDCLK_DELAY_MASK)
72 				<< SDCLK_DELAY_SHIFT;
73 			tmp &= ~(SDCLK_SEL_MASK << SDCLK_SEL_SHIFT);
74 			tmp |= (1 & SDCLK_SEL_MASK) << SDCLK_SEL_SHIFT;
75 
76 			writew(tmp, host->ioaddr + SD_CLOCK_BURST_SIZE_SETUP);
77 		}
78 
79 		if (pdata && (pdata->flags & PXA_FLAG_ENABLE_CLOCK_GATING)) {
80 			tmp = readw(host->ioaddr + SD_FIFO_PARAM);
81 			tmp &= ~CLK_GATE_SETTING_BITS;
82 			writew(tmp, host->ioaddr + SD_FIFO_PARAM);
83 		} else {
84 			tmp = readw(host->ioaddr + SD_FIFO_PARAM);
85 			tmp &= ~CLK_GATE_SETTING_BITS;
86 			tmp |= CLK_GATE_SETTING_BITS;
87 			writew(tmp, host->ioaddr + SD_FIFO_PARAM);
88 		}
89 	}
90 }
91 
92 static void pxav2_mmc_set_bus_width(struct sdhci_host *host, int width)
93 {
94 	u8 ctrl;
95 	u16 tmp;
96 
97 	ctrl = readb(host->ioaddr + SDHCI_HOST_CONTROL);
98 	tmp = readw(host->ioaddr + SD_CE_ATA_2);
99 	if (width == MMC_BUS_WIDTH_8) {
100 		ctrl &= ~SDHCI_CTRL_4BITBUS;
101 		tmp |= MMC_CARD | MMC_WIDTH;
102 	} else {
103 		tmp &= ~(MMC_CARD | MMC_WIDTH);
104 		if (width == MMC_BUS_WIDTH_4)
105 			ctrl |= SDHCI_CTRL_4BITBUS;
106 		else
107 			ctrl &= ~SDHCI_CTRL_4BITBUS;
108 	}
109 	writew(tmp, host->ioaddr + SD_CE_ATA_2);
110 	writeb(ctrl, host->ioaddr + SDHCI_HOST_CONTROL);
111 }
112 
113 static const struct sdhci_ops pxav2_sdhci_ops = {
114 	.set_clock     = sdhci_set_clock,
115 	.get_max_clock = sdhci_pltfm_clk_get_max_clock,
116 	.set_bus_width = pxav2_mmc_set_bus_width,
117 	.reset         = pxav2_reset,
118 	.set_uhs_signaling = sdhci_set_uhs_signaling,
119 };
120 
121 #ifdef CONFIG_OF
122 static const struct of_device_id sdhci_pxav2_of_match[] = {
123 	{
124 		.compatible = "mrvl,pxav2-mmc",
125 	},
126 	{},
127 };
128 MODULE_DEVICE_TABLE(of, sdhci_pxav2_of_match);
129 
130 static struct sdhci_pxa_platdata *pxav2_get_mmc_pdata(struct device *dev)
131 {
132 	struct sdhci_pxa_platdata *pdata;
133 	struct device_node *np = dev->of_node;
134 	u32 bus_width;
135 	u32 clk_delay_cycles;
136 
137 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
138 	if (!pdata)
139 		return NULL;
140 
141 	if (of_find_property(np, "non-removable", NULL))
142 		pdata->flags |= PXA_FLAG_CARD_PERMANENT;
143 
144 	of_property_read_u32(np, "bus-width", &bus_width);
145 	if (bus_width == 8)
146 		pdata->flags |= PXA_FLAG_SD_8_BIT_CAPABLE_SLOT;
147 
148 	of_property_read_u32(np, "mrvl,clk-delay-cycles", &clk_delay_cycles);
149 	if (clk_delay_cycles > 0) {
150 		pdata->clk_delay_sel = 1;
151 		pdata->clk_delay_cycles = clk_delay_cycles;
152 	}
153 
154 	return pdata;
155 }
156 #else
157 static inline struct sdhci_pxa_platdata *pxav2_get_mmc_pdata(struct device *dev)
158 {
159 	return NULL;
160 }
161 #endif
162 
163 static int sdhci_pxav2_probe(struct platform_device *pdev)
164 {
165 	struct sdhci_pltfm_host *pltfm_host;
166 	struct sdhci_pxa_platdata *pdata = pdev->dev.platform_data;
167 	struct device *dev = &pdev->dev;
168 	struct sdhci_host *host = NULL;
169 	const struct of_device_id *match;
170 
171 	int ret;
172 	struct clk *clk;
173 
174 	host = sdhci_pltfm_init(pdev, NULL, 0);
175 	if (IS_ERR(host))
176 		return PTR_ERR(host);
177 
178 	pltfm_host = sdhci_priv(host);
179 
180 	clk = devm_clk_get(dev, "PXA-SDHCLK");
181 	if (IS_ERR(clk)) {
182 		dev_err(dev, "failed to get io clock\n");
183 		ret = PTR_ERR(clk);
184 		goto free;
185 	}
186 	pltfm_host->clk = clk;
187 	ret = clk_prepare_enable(clk);
188 	if (ret) {
189 		dev_err(&pdev->dev, "failed to enable io clock\n");
190 		goto free;
191 	}
192 
193 	host->quirks = SDHCI_QUIRK_BROKEN_ADMA
194 		| SDHCI_QUIRK_BROKEN_TIMEOUT_VAL
195 		| SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN;
196 
197 	match = of_match_device(of_match_ptr(sdhci_pxav2_of_match), &pdev->dev);
198 	if (match) {
199 		pdata = pxav2_get_mmc_pdata(dev);
200 	}
201 	if (pdata) {
202 		if (pdata->flags & PXA_FLAG_CARD_PERMANENT) {
203 			/* on-chip device */
204 			host->quirks |= SDHCI_QUIRK_BROKEN_CARD_DETECTION;
205 			host->mmc->caps |= MMC_CAP_NONREMOVABLE;
206 		}
207 
208 		/* If slot design supports 8 bit data, indicate this to MMC. */
209 		if (pdata->flags & PXA_FLAG_SD_8_BIT_CAPABLE_SLOT)
210 			host->mmc->caps |= MMC_CAP_8_BIT_DATA;
211 
212 		if (pdata->quirks)
213 			host->quirks |= pdata->quirks;
214 		if (pdata->host_caps)
215 			host->mmc->caps |= pdata->host_caps;
216 		if (pdata->pm_caps)
217 			host->mmc->pm_caps |= pdata->pm_caps;
218 	}
219 
220 	host->ops = &pxav2_sdhci_ops;
221 
222 	ret = sdhci_add_host(host);
223 	if (ret)
224 		goto disable_clk;
225 
226 	return 0;
227 
228 disable_clk:
229 	clk_disable_unprepare(clk);
230 free:
231 	sdhci_pltfm_free(pdev);
232 	return ret;
233 }
234 
235 static struct platform_driver sdhci_pxav2_driver = {
236 	.driver		= {
237 		.name	= "sdhci-pxav2",
238 		.of_match_table = of_match_ptr(sdhci_pxav2_of_match),
239 		.pm	= &sdhci_pltfm_pmops,
240 	},
241 	.probe		= sdhci_pxav2_probe,
242 	.remove		= sdhci_pltfm_unregister,
243 };
244 
245 module_platform_driver(sdhci_pxav2_driver);
246 
247 MODULE_DESCRIPTION("SDHCI driver for pxav2");
248 MODULE_AUTHOR("Marvell International Ltd.");
249 MODULE_LICENSE("GPL v2");
250 
251