WSL2-Linux-Kernel/drivers/mtd/nand/toto.c

207 строки
4.8 KiB
C

/*
* drivers/mtd/nand/toto.c
*
* Copyright (c) 2003 Texas Instruments
*
* Derived from drivers/mtd/autcpu12.c
*
* Copyright (c) 2002 Thomas Gleixner <tgxl@linutronix.de>
*
* 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.
*
* Overview:
* This is a device driver for the NAND flash device found on the
* TI fido board. It supports 32MiB and 64MiB cards
*/
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/nand.h>
#include <linux/mtd/partitions.h>
#include <asm/io.h>
#include <asm/arch/hardware.h>
#include <asm/sizes.h>
#include <asm/arch/toto.h>
#include <asm/arch-omap1510/hardware.h>
#include <asm/arch/gpio.h>
#define CONFIG_NAND_WORKAROUND 1
/*
* MTD structure for TOTO board
*/
static struct mtd_info *toto_mtd = NULL;
static unsigned long toto_io_base = OMAP_FLASH_1_BASE;
/*
* Define partitions for flash devices
*/
static struct mtd_partition partition_info64M[] = {
{ .name = "toto kernel partition 1",
.offset = 0,
.size = 2 * SZ_1M },
{ .name = "toto file sys partition 2",
.offset = 2 * SZ_1M,
.size = 14 * SZ_1M },
{ .name = "toto user partition 3",
.offset = 16 * SZ_1M,
.size = 16 * SZ_1M },
{ .name = "toto devboard extra partition 4",
.offset = 32 * SZ_1M,
.size = 32 * SZ_1M },
};
static struct mtd_partition partition_info32M[] = {
{ .name = "toto kernel partition 1",
.offset = 0,
.size = 2 * SZ_1M },
{ .name = "toto file sys partition 2",
.offset = 2 * SZ_1M,
.size = 14 * SZ_1M },
{ .name = "toto user partition 3",
.offset = 16 * SZ_1M,
.size = 16 * SZ_1M },
};
#define NUM_PARTITIONS32M 3
#define NUM_PARTITIONS64M 4
/*
* hardware specific access to control-lines
*
* ctrl:
* NAND_NCE: bit 0 -> bit 14 (0x4000)
* NAND_CLE: bit 1 -> bit 12 (0x1000)
* NAND_ALE: bit 2 -> bit 1 (0x0002)
*/
static void toto_hwcontrol(struct mtd_info *mtd, int cmd,
unsigned int ctrl)
{
struct nand_chip *chip = mtd->priv;
if (ctrl & NAND_CTRL_CHANGE) {
unsigned long bits;
/* hopefully enough time for tc make proceding write to clear */
udelay(1);
bits = (~ctrl & NAND_NCE) << 14;
bits |= (ctrl & NAND_CLE) << 12;
bits |= (ctrl & NAND_ALE) >> 1;
#warning Wild guess as gpiosetout() is nowhere defined in the kernel source - tglx
gpiosetout(0x5002, bits);
#ifdef CONFIG_NAND_WORKAROUND
/* "some" dev boards busted, blue wired to rts2 :( */
rts2setout(2, (ctrl & NAND_CLE) << 1);
#endif
/* allow time to ensure gpio state to over take memory write */
udelay(1);
}
if (cmd != NAND_CMD_NONE)
writeb(cmd, chip->IO_ADDR_W);
}
/*
* Main initialization routine
*/
static int __init toto_init(void)
{
struct nand_chip *this;
int err = 0;
/* Allocate memory for MTD device structure and private data */
toto_mtd = kmalloc(sizeof(struct mtd_info) + sizeof(struct nand_chip), GFP_KERNEL);
if (!toto_mtd) {
printk(KERN_WARNING "Unable to allocate toto NAND MTD device structure.\n");
err = -ENOMEM;
goto out;
}
/* Get pointer to private data */
this = (struct nand_chip *)(&toto_mtd[1]);
/* Initialize structures */
memset(toto_mtd, 0, sizeof(struct mtd_info));
memset(this, 0, sizeof(struct nand_chip));
/* Link the private data with the MTD structure */
toto_mtd->priv = this;
toto_mtd->owner = THIS_MODULE;
/* Set address of NAND IO lines */
this->IO_ADDR_R = toto_io_base;
this->IO_ADDR_W = toto_io_base;
this->cmd_ctrl = toto_hwcontrol;
this->dev_ready = NULL;
/* 25 us command delay time */
this->chip_delay = 30;
this->ecc.mode = NAND_ECC_SOFT;
/* Scan to find existance of the device */
if (nand_scan(toto_mtd, 1)) {
err = -ENXIO;
goto out_mtd;
}
/* Register the partitions */
switch (toto_mtd->size) {
case SZ_64M:
add_mtd_partitions(toto_mtd, partition_info64M, NUM_PARTITIONS64M);
break;
case SZ_32M:
add_mtd_partitions(toto_mtd, partition_info32M, NUM_PARTITIONS32M);
break;
default:{
printk(KERN_WARNING "Unsupported Nand device\n");
err = -ENXIO;
goto out_buf;
}
}
gpioreserve(NAND_MASK); /* claim our gpios */
archflashwp(0, 0); /* open up flash for writing */
goto out;
out_mtd:
kfree(toto_mtd);
out:
return err;
}
module_init(toto_init);
/*
* Clean up routine
*/
static void __exit toto_cleanup(void)
{
/* Release resources, unregister device */
nand_release(toto_mtd);
/* Free the MTD device structure */
kfree(toto_mtd);
/* stop flash writes */
archflashwp(0, 1);
/* release gpios to system */
gpiorelease(NAND_MASK);
}
module_exit(toto_cleanup);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Richard Woodruff <r-woodruff2@ti.com>");
MODULE_DESCRIPTION("Glue layer for NAND flash on toto board");