summaryrefslogtreecommitdiffstats
path: root/drivers/mmc/host/sdhci-of-esdhc.c
blob: d5b11a17e64805c7e5e8531d192afdd0230a1805 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
/*
 * Freescale eSDHC controller driver.
 *
 * Copyright (c) 2007 Freescale Semiconductor, Inc.
 * Copyright (c) 2009 MontaVista Software, Inc.
 *
 * Authors: Xiaobo Xie <X.Xie@freescale.com>
 *	    Anton Vorontsov <avorontsov@ru.mvista.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or (at
 * your option) any later version.
 */

#include <linux/io.h>
#include <linux/delay.h>
#include <linux/mmc/host.h>
#include "sdhci-of.h"
#include "sdhci.h"

/*
 * Ops and quirks for the Freescale eSDHC controller.
 */

#define ESDHC_DMA_SYSCTL	0x40c
#define ESDHC_DMA_SNOOP		0x00000040

#define ESDHC_SYSTEM_CONTROL	0x2c
#define ESDHC_CLOCK_MASK	0x0000fff0
#define ESDHC_PREDIV_SHIFT	8
#define ESDHC_DIVIDER_SHIFT	4
#define ESDHC_CLOCK_PEREN	0x00000004
#define ESDHC_CLOCK_HCKEN	0x00000002
#define ESDHC_CLOCK_IPGEN	0x00000001

#define ESDHC_HOST_CONTROL_RES	0x05

static u16 esdhc_readw(struct sdhci_host *host, int reg)
{
	u16 ret;

	if (unlikely(reg == SDHCI_HOST_VERSION))
		ret = in_be16(host->ioaddr + reg);
	else
		ret = sdhci_be32bs_readw(host, reg);
	return ret;
}

static void esdhc_writew(struct sdhci_host *host, u16 val, int reg)
{
	if (reg == SDHCI_BLOCK_SIZE) {
		/*
		 * Two last DMA bits are reserved, and first one is used for
		 * non-standard blksz of 4096 bytes that we don't support
		 * yet. So clear the DMA boundary bits.
		 */
		val &= ~SDHCI_MAKE_BLKSZ(0x7, 0);
	}
	sdhci_be32bs_writew(host, val, reg);
}

static void esdhc_writeb(struct sdhci_host *host, u8 val, int reg)
{
	/* Prevent SDHCI core from writing reserved bits (e.g. HISPD). */
	if (reg == SDHCI_HOST_CONTROL)
		val &= ~ESDHC_HOST_CONTROL_RES;
	sdhci_be32bs_writeb(host, val, reg);
}

static void esdhc_set_clock(struct sdhci_host *host, unsigned int clock)
{
	int pre_div = 2;
	int div = 1;

	clrbits32(host->ioaddr + ESDHC_SYSTEM_CONTROL, ESDHC_CLOCK_IPGEN |
		  ESDHC_CLOCK_HCKEN | ESDHC_CLOCK_PEREN | ESDHC_CLOCK_MASK);

	if (clock == 0)
		goto out;

	while (host->max_clk / pre_div / 16 > clock && pre_div < 256)
		pre_div *= 2;

	while (host->max_clk / pre_div / div > clock && div < 16)
		div++;

	dev_dbg(mmc_dev(host->mmc), "desired SD clock: %d, actual: %d\n",
		clock, host->max_clk / pre_div / div);

	pre_div >>= 1;
	div--;

	setbits32(host->ioaddr + ESDHC_SYSTEM_CONTROL, ESDHC_CLOCK_IPGEN |
		  ESDHC_CLOCK_HCKEN | ESDHC_CLOCK_PEREN |
		  div << ESDHC_DIVIDER_SHIFT | pre_div << ESDHC_PREDIV_SHIFT);
	mdelay(100);
out:
	host->clock = clock;
}

static int esdhc_enable_dma(struct sdhci_host *host)
{
	setbits32(host->ioaddr + ESDHC_DMA_SYSCTL, ESDHC_DMA_SNOOP);
	return 0;
}

static unsigned int esdhc_get_max_clock(struct sdhci_host *host)
{
	struct sdhci_of_host *of_host = sdhci_priv(host);

	return of_host->clock;
}

static unsigned int esdhc_get_min_clock(struct sdhci_host *host)
{
	struct sdhci_of_host *of_host = sdhci_priv(host);

	return of_host->clock / 256 / 16;
}

struct sdhci_of_data sdhci_esdhc = {
	.quirks = SDHCI_QUIRK_FORCE_BLK_SZ_2048 |
		  SDHCI_QUIRK_BROKEN_CARD_DETECTION |
		  SDHCI_QUIRK_NO_BUSY_IRQ |
		  SDHCI_QUIRK_NONSTANDARD_CLOCK |
		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
		  SDHCI_QUIRK_PIO_NEEDS_DELAY |
		  SDHCI_QUIRK_RESTORE_IRQS_AFTER_RESET |
		  SDHCI_QUIRK_NO_CARD_NO_RESET,
	.ops = {
		.readl = sdhci_be32bs_readl,
		.readw = esdhc_readw,
		.readb = sdhci_be32bs_readb,
		.writel = sdhci_be32bs_writel,
		.writew = esdhc_writew,
		.writeb = esdhc_writeb,
		.set_clock = esdhc_set_clock,
		.enable_dma = esdhc_enable_dma,
		.get_max_clock = esdhc_get_max_clock,
		.get_min_clock = esdhc_get_min_clock,
	},
};
OpenPOWER on IntegriCloud