xref: /openbmc/linux/drivers/mmc/host/sdhci-esdhc-imx.c (revision baa7eb025ab14f3cba2e35c0a8648f9c9f01d24f)
1 /*
2  * Freescale eSDHC i.MX controller driver for the platform bus.
3  *
4  * derived from the OF-version.
5  *
6  * Copyright (c) 2010 Pengutronix e.K.
7  *   Author: Wolfram Sang <w.sang@pengutronix.de>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License.
12  */
13 
14 #include <linux/io.h>
15 #include <linux/delay.h>
16 #include <linux/err.h>
17 #include <linux/clk.h>
18 #include <linux/mmc/host.h>
19 #include <linux/mmc/sdhci-pltfm.h>
20 #include <mach/hardware.h>
21 #include "sdhci.h"
22 #include "sdhci-pltfm.h"
23 #include "sdhci-esdhc.h"
24 
25 static inline void esdhc_clrset_le(struct sdhci_host *host, u32 mask, u32 val, int reg)
26 {
27 	void __iomem *base = host->ioaddr + (reg & ~0x3);
28 	u32 shift = (reg & 0x3) * 8;
29 
30 	writel(((readl(base) & ~(mask << shift)) | (val << shift)), base);
31 }
32 
33 static u16 esdhc_readw_le(struct sdhci_host *host, int reg)
34 {
35 	if (unlikely(reg == SDHCI_HOST_VERSION))
36 		reg ^= 2;
37 
38 	return readw(host->ioaddr + reg);
39 }
40 
41 static void esdhc_writew_le(struct sdhci_host *host, u16 val, int reg)
42 {
43 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
44 
45 	switch (reg) {
46 	case SDHCI_TRANSFER_MODE:
47 		/*
48 		 * Postpone this write, we must do it together with a
49 		 * command write that is down below.
50 		 */
51 		pltfm_host->scratchpad = val;
52 		return;
53 	case SDHCI_COMMAND:
54 		writel(val << 16 | pltfm_host->scratchpad,
55 			host->ioaddr + SDHCI_TRANSFER_MODE);
56 		return;
57 	case SDHCI_BLOCK_SIZE:
58 		val &= ~SDHCI_MAKE_BLKSZ(0x7, 0);
59 		break;
60 	}
61 	esdhc_clrset_le(host, 0xffff, val, reg);
62 }
63 
64 static void esdhc_writeb_le(struct sdhci_host *host, u8 val, int reg)
65 {
66 	u32 new_val;
67 
68 	switch (reg) {
69 	case SDHCI_POWER_CONTROL:
70 		/*
71 		 * FSL put some DMA bits here
72 		 * If your board has a regulator, code should be here
73 		 */
74 		return;
75 	case SDHCI_HOST_CONTROL:
76 		/* FSL messed up here, so we can just keep those two */
77 		new_val = val & (SDHCI_CTRL_LED | SDHCI_CTRL_4BITBUS);
78 		/* ensure the endianess */
79 		new_val |= ESDHC_HOST_CONTROL_LE;
80 		/* DMA mode bits are shifted */
81 		new_val |= (val & SDHCI_CTRL_DMA_MASK) << 5;
82 
83 		esdhc_clrset_le(host, 0xffff, new_val, reg);
84 		return;
85 	}
86 	esdhc_clrset_le(host, 0xff, val, reg);
87 }
88 
89 static unsigned int esdhc_pltfm_get_max_clock(struct sdhci_host *host)
90 {
91 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
92 
93 	return clk_get_rate(pltfm_host->clk);
94 }
95 
96 static unsigned int esdhc_pltfm_get_min_clock(struct sdhci_host *host)
97 {
98 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
99 
100 	return clk_get_rate(pltfm_host->clk) / 256 / 16;
101 }
102 
103 static int esdhc_pltfm_init(struct sdhci_host *host, struct sdhci_pltfm_data *pdata)
104 {
105 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
106 	struct clk *clk;
107 
108 	clk = clk_get(mmc_dev(host->mmc), NULL);
109 	if (IS_ERR(clk)) {
110 		dev_err(mmc_dev(host->mmc), "clk err\n");
111 		return PTR_ERR(clk);
112 	}
113 	clk_enable(clk);
114 	pltfm_host->clk = clk;
115 
116 	if (cpu_is_mx35() || cpu_is_mx51())
117 		host->quirks |= SDHCI_QUIRK_BROKEN_TIMEOUT_VAL;
118 
119 	/* Fix errata ENGcm07207 which is present on i.MX25 and i.MX35 */
120 	if (cpu_is_mx25() || cpu_is_mx35())
121 		host->quirks |= SDHCI_QUIRK_NO_MULTIBLOCK;
122 
123 	return 0;
124 }
125 
126 static void esdhc_pltfm_exit(struct sdhci_host *host)
127 {
128 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
129 
130 	clk_disable(pltfm_host->clk);
131 	clk_put(pltfm_host->clk);
132 }
133 
134 static struct sdhci_ops sdhci_esdhc_ops = {
135 	.read_w = esdhc_readw_le,
136 	.write_w = esdhc_writew_le,
137 	.write_b = esdhc_writeb_le,
138 	.set_clock = esdhc_set_clock,
139 	.get_max_clock = esdhc_pltfm_get_max_clock,
140 	.get_min_clock = esdhc_pltfm_get_min_clock,
141 };
142 
143 struct sdhci_pltfm_data sdhci_esdhc_imx_pdata = {
144 	.quirks = ESDHC_DEFAULT_QUIRKS | SDHCI_QUIRK_BROKEN_ADMA,
145 	/* ADMA has issues. Might be fixable */
146 	.ops = &sdhci_esdhc_ops,
147 	.init = esdhc_pltfm_init,
148 	.exit = esdhc_pltfm_exit,
149 };
150