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
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
|
/*
* arch/cris/arch-v32/drivers/nandflash.c
*
* Copyright (c) 2007
*
* Derived from drivers/mtd/nand/spia.c
* Copyright (C) 2000 Steven J. Hill (sjhill@realitydiluted.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/slab.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/nand.h>
#include <linux/mtd/partitions.h>
#include <arch/memmap.h>
#include <hwregs/reg_map.h>
#include <hwregs/reg_rdwr.h>
#include <hwregs/pio_defs.h>
#include <pinmux.h>
#include <asm/io.h>
#define MANUAL_ALE_CLE_CONTROL 1
#define regf_ALE a0
#define regf_CLE a1
#define regf_NCE ce0_n
#define CLE_BIT 10
#define ALE_BIT 11
#define CE_BIT 12
struct mtd_info_wrapper {
struct mtd_info info;
struct nand_chip chip;
};
/* Bitmask for control pins */
#define PIN_BITMASK ((1 << CE_BIT) | (1 << CLE_BIT) | (1 << ALE_BIT))
static struct mtd_info *crisv32_mtd;
/*
* hardware specific access to control-lines
*/
static void crisv32_hwcontrol(struct mtd_info *mtd, int cmd,
unsigned int ctrl)
{
unsigned long flags;
reg_pio_rw_dout dout;
struct nand_chip *this = mtd->priv;
local_irq_save(flags);
/* control bits change */
if (ctrl & NAND_CTRL_CHANGE) {
dout = REG_RD(pio, regi_pio, rw_dout);
dout.regf_NCE = (ctrl & NAND_NCE) ? 0 : 1;
#if !MANUAL_ALE_CLE_CONTROL
if (ctrl & NAND_ALE) {
/* A0 = ALE high */
this->IO_ADDR_W = (void __iomem *)REG_ADDR(pio,
regi_pio, rw_io_access1);
} else if (ctrl & NAND_CLE) {
/* A1 = CLE high */
this->IO_ADDR_W = (void __iomem *)REG_ADDR(pio,
regi_pio, rw_io_access2);
} else {
/* A1 = CLE and A0 = ALE low */
this->IO_ADDR_W = (void __iomem *)REG_ADDR(pio,
regi_pio, rw_io_access0);
}
#else
dout.regf_CLE = (ctrl & NAND_CLE) ? 1 : 0;
dout.regf_ALE = (ctrl & NAND_ALE) ? 1 : 0;
#endif
REG_WR(pio, regi_pio, rw_dout, dout);
}
/* command to chip */
if (cmd != NAND_CMD_NONE)
writeb(cmd, this->IO_ADDR_W);
local_irq_restore(flags);
}
/*
* read device ready pin
*/
static int crisv32_device_ready(struct mtd_info *mtd)
{
reg_pio_r_din din = REG_RD(pio, regi_pio, r_din);
return din.rdy;
}
/*
* Main initialization routine
*/
struct mtd_info *__init crisv32_nand_flash_probe(void)
{
void __iomem *read_cs;
void __iomem *write_cs;
struct mtd_info_wrapper *wrapper;
struct nand_chip *this;
int err = 0;
reg_pio_rw_man_ctrl man_ctrl = {
.regf_NCE = regk_pio_yes,
#if MANUAL_ALE_CLE_CONTROL
.regf_ALE = regk_pio_yes,
.regf_CLE = regk_pio_yes
#endif
};
reg_pio_rw_oe oe = {
.regf_NCE = regk_pio_yes,
#if MANUAL_ALE_CLE_CONTROL
.regf_ALE = regk_pio_yes,
.regf_CLE = regk_pio_yes
#endif
};
reg_pio_rw_dout dout = { .regf_NCE = 1 };
/* Allocate pio pins to pio */
crisv32_pinmux_alloc_fixed(pinmux_pio);
/* Set up CE, ALE, CLE (ce0_n, a0, a1) for manual control and output */
REG_WR(pio, regi_pio, rw_man_ctrl, man_ctrl);
REG_WR(pio, regi_pio, rw_dout, dout);
REG_WR(pio, regi_pio, rw_oe, oe);
/* Allocate memory for MTD device structure and private data */
wrapper = kzalloc(sizeof(struct mtd_info_wrapper), GFP_KERNEL);
if (!wrapper) {
printk(KERN_ERR "Unable to allocate CRISv32 NAND MTD "
"device structure.\n");
err = -ENOMEM;
return NULL;
}
read_cs = write_cs = (void __iomem *)REG_ADDR(pio, regi_pio,
rw_io_access0);
/* Get pointer to private data */
this = &wrapper->chip;
crisv32_mtd = &wrapper->info;
/* Link the private data with the MTD structure */
crisv32_mtd->priv = this;
/* Set address of NAND IO lines */
this->IO_ADDR_R = read_cs;
this->IO_ADDR_W = write_cs;
this->cmd_ctrl = crisv32_hwcontrol;
this->dev_ready = crisv32_device_ready;
/* 20 us command delay time */
this->chip_delay = 20;
this->ecc.mode = NAND_ECC_SOFT;
/* Enable the following for a flash based bad block table */
/* this->options = NAND_USE_FLASH_BBT; */
/* Scan to find existence of the device */
if (nand_scan(crisv32_mtd, 1)) {
err = -ENXIO;
goto out_mtd;
}
return crisv32_mtd;
out_mtd:
kfree(wrapper);
return NULL;
}
|
