summaryrefslogtreecommitdiffstats
path: root/arch/arm/mach-omap2/gpmc-nand.c
blob: 93914d2200691ca3e27a6b74d04ce3b52eb02703 (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
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
/*
 * gpmc-nand.c
 *
 * Copyright (C) 2009 Texas Instruments
 * Vimal Singh <vimalsingh@ti.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/mtd/nand.h>
#include <linux/platform_data/mtd-nand-omap2.h>

#include <asm/mach/flash.h>

#include "gpmc.h"
#include "soc.h"
#include "gpmc-nand.h"

/* minimum size for IO mapping */
#define	NAND_IO_SIZE	4

static struct resource gpmc_nand_resource[] = {
	{
		.flags		= IORESOURCE_MEM,
	},
	{
		.flags		= IORESOURCE_IRQ,
	},
	{
		.flags		= IORESOURCE_IRQ,
	},
};

static struct platform_device gpmc_nand_device = {
	.name		= "omap2-nand",
	.id		= 0,
	.num_resources	= ARRAY_SIZE(gpmc_nand_resource),
	.resource	= gpmc_nand_resource,
};

static bool gpmc_hwecc_bch_capable(enum omap_ecc ecc_opt)
{
	/* platforms which support all ECC schemes */
	if (soc_is_am33xx() || soc_is_am43xx() || cpu_is_omap44xx() ||
		 soc_is_omap54xx() || soc_is_dra7xx())
		return 1;

	if (ecc_opt == OMAP_ECC_BCH4_CODE_HW_DETECTION_SW ||
		 ecc_opt == OMAP_ECC_BCH8_CODE_HW_DETECTION_SW) {
		if (cpu_is_omap24xx())
			return 0;
		else if (cpu_is_omap3630() && (GET_OMAP_REVISION() == 0))
			return 0;
		else
			return 1;
	}

	/* OMAP3xxx do not have ELM engine, so cannot support ECC schemes
	 * which require H/W based ECC error detection */
	if ((cpu_is_omap34xx() || cpu_is_omap3630()) &&
	    ((ecc_opt == OMAP_ECC_BCH4_CODE_HW) ||
		 (ecc_opt == OMAP_ECC_BCH8_CODE_HW)))
		return 0;

	/* legacy platforms support only HAM1 (1-bit Hamming) ECC scheme */
	if (ecc_opt == OMAP_ECC_HAM1_CODE_HW)
		return 1;
	else
		return 0;
}

/* This function will go away once the device-tree convertion is complete */
static void gpmc_set_legacy(struct omap_nand_platform_data *gpmc_nand_data,
			    struct gpmc_settings *s)
{
	/* Enable RD PIN Monitoring Reg */
	if (gpmc_nand_data->dev_ready) {
		s->wait_on_read = true;
		s->wait_on_write = true;
	}

	if (gpmc_nand_data->devsize == NAND_BUSWIDTH_16)
		s->device_width = GPMC_DEVWIDTH_16BIT;
	else
		s->device_width = GPMC_DEVWIDTH_8BIT;
}

int gpmc_nand_init(struct omap_nand_platform_data *gpmc_nand_data,
		   struct gpmc_timings *gpmc_t)
{
	int err	= 0;
	struct gpmc_settings s;
	struct device *dev = &gpmc_nand_device.dev;

	memset(&s, 0, sizeof(struct gpmc_settings));

	gpmc_nand_device.dev.platform_data = gpmc_nand_data;

	err = gpmc_cs_request(gpmc_nand_data->cs, NAND_IO_SIZE,
				(unsigned long *)&gpmc_nand_resource[0].start);
	if (err < 0) {
		dev_err(dev, "Cannot request GPMC CS %d, error %d\n",
			gpmc_nand_data->cs, err);
		return err;
	}

	gpmc_nand_resource[0].end = gpmc_nand_resource[0].start +
							NAND_IO_SIZE - 1;

	gpmc_nand_resource[1].start =
				gpmc_get_client_irq(GPMC_IRQ_FIFOEVENTENABLE);
	gpmc_nand_resource[2].start =
				gpmc_get_client_irq(GPMC_IRQ_COUNT_EVENT);

	if (gpmc_t) {
		err = gpmc_cs_set_timings(gpmc_nand_data->cs, gpmc_t);
		if (err < 0) {
			dev_err(dev, "Unable to set gpmc timings: %d\n", err);
			return err;
		}
	}

	if (gpmc_nand_data->of_node)
		gpmc_read_settings_dt(gpmc_nand_data->of_node, &s);
	else
		gpmc_set_legacy(gpmc_nand_data, &s);

	s.device_nand = true;

	err = gpmc_cs_program_settings(gpmc_nand_data->cs, &s);
	if (err < 0)
		goto out_free_cs;

	err = gpmc_configure(GPMC_CONFIG_WP, 0);
	if (err < 0)
		goto out_free_cs;

	gpmc_update_nand_reg(&gpmc_nand_data->reg, gpmc_nand_data->cs);

	if (!gpmc_hwecc_bch_capable(gpmc_nand_data->ecc_opt)) {
		dev_err(dev, "Unsupported NAND ECC scheme selected\n");
		return -EINVAL;
	}

	err = platform_device_register(&gpmc_nand_device);
	if (err < 0) {
		dev_err(dev, "Unable to register NAND device\n");
		goto out_free_cs;
	}

	return 0;

out_free_cs:
	gpmc_cs_free(gpmc_nand_data->cs);

	return err;
}
OpenPOWER on IntegriCloud