linux/drivers/mtd/nand/ts7250.c
Thomas Gleixner 7abd3ef987 [MTD] Refactor NAND hwcontrol to cmd_ctrl
The hwcontrol function enforced a step by step state machine
for any kind of hardware chip access. Let the hardware driver
know which control bits are set and inform it about a change
of the control lines. Let the hardware driver write out the
command and address bytes directly. This gives a peformance
advantage for address bus controlled chips and simplifies the
quirks in the hardware drivers.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2006-05-23 23:25:53 +02:00

207 lines
4.8 KiB
C

/*
* drivers/mtd/nand/ts7250.c
*
* Copyright (C) 2004 Technologic Systems (support@embeddedARM.com)
*
* Derived from drivers/mtd/nand/edb7312.c
* Copyright (C) 2004 Marius Gröger (mag@sysgo.de)
*
* Derived from drivers/mtd/nand/autcpu12.c
* Copyright (c) 2001 Thomas Gleixner (gleixner@autronix.de)
*
* $Id: ts7250.c,v 1.4 2004/12/30 22:02:07 joff Exp $
*
* 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
* TS-7250 board which utilizes a Samsung 32 Mbyte part.
*/
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/init.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/mach-types.h>
/*
* MTD structure for TS7250 board
*/
static struct mtd_info *ts7250_mtd = NULL;
#ifdef CONFIG_MTD_PARTITIONS
static const char *part_probes[] = { "cmdlinepart", NULL };
#define NUM_PARTITIONS 3
/*
* Define static partitions for flash device
*/
static struct mtd_partition partition_info32[] = {
{
.name = "TS-BOOTROM",
.offset = 0x00000000,
.size = 0x00004000,
}, {
.name = "Linux",
.offset = 0x00004000,
.size = 0x01d00000,
}, {
.name = "RedBoot",
.offset = 0x01d04000,
.size = 0x002fc000,
},
};
/*
* Define static partitions for flash device
*/
static struct mtd_partition partition_info128[] = {
{
.name = "TS-BOOTROM",
.offset = 0x00000000,
.size = 0x00004000,
}, {
.name = "Linux",
.offset = 0x00004000,
.size = 0x07d00000,
}, {
.name = "RedBoot",
.offset = 0x07d04000,
.size = 0x002fc000,
},
};
#endif
/*
* hardware specific access to control-lines
*
* ctrl:
* NAND_NCE: bit 0 -> bit 2
* NAND_CLE: bit 1 -> bit 1
* NAND_ALE: bit 2 -> bit 0
*/
static void ts7250_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl)
{
struct nand_chip *chip = mtd->priv;
if (ctrl & NAND_CTRL_CHANGE) {
unsigned long addr = TS72XX_NAND_CONTROL_VIRT_BASE;
unsigned char bits;
bits = (ctrl & NAND_CNE) << 2;
bits |= ctrl & NAND_CLE;
bits |= (ctrl & NAND_ALE) >> 2;
__raw_writeb((__raw_readb(addr) & ~0x7) | bits, addr);
}
if (cmd != NAND_CMD_NONE)
writeb(cmd, chip->IO_ADDR_W);
}
/*
* read device ready pin
*/
static int ts7250_device_ready(struct mtd_info *mtd)
{
return __raw_readb(TS72XX_NAND_BUSY_VIRT_BASE) & 0x20;
}
/*
* Main initialization routine
*/
static int __init ts7250_init(void)
{
struct nand_chip *this;
const char *part_type = 0;
int mtd_parts_nb = 0;
struct mtd_partition *mtd_parts = 0;
if (!machine_is_ts72xx() || board_is_ts7200())
return -ENXIO;
/* Allocate memory for MTD device structure and private data */
ts7250_mtd = kmalloc(sizeof(struct mtd_info) + sizeof(struct nand_chip), GFP_KERNEL);
if (!ts7250_mtd) {
printk("Unable to allocate TS7250 NAND MTD device structure.\n");
return -ENOMEM;
}
/* Get pointer to private data */
this = (struct nand_chip *)(&ts7250_mtd[1]);
/* Initialize structures */
memset(ts7250_mtd, 0, sizeof(struct mtd_info));
memset(this, 0, sizeof(struct nand_chip));
/* Link the private data with the MTD structure */
ts7250_mtd->priv = this;
ts7250_mtd->owner = THIS_MODULE;
/* insert callbacks */
this->IO_ADDR_R = (void *)TS72XX_NAND_DATA_VIRT_BASE;
this->IO_ADDR_W = (void *)TS72XX_NAND_DATA_VIRT_BASE;
this->cmd_ctrl = ts7250_hwcontrol;
this->dev_ready = ts7250_device_ready;
this->chip_delay = 15;
this->ecc.mode = NAND_ECC_SOFT;
printk("Searching for NAND flash...\n");
/* Scan to find existence of the device */
if (nand_scan(ts7250_mtd, 1)) {
kfree(ts7250_mtd);
return -ENXIO;
}
#ifdef CONFIG_MTD_PARTITIONS
ts7250_mtd->name = "ts7250-nand";
mtd_parts_nb = parse_mtd_partitions(ts7250_mtd, part_probes, &mtd_parts, 0);
if (mtd_parts_nb > 0)
part_type = "command line";
else
mtd_parts_nb = 0;
#endif
if (mtd_parts_nb == 0) {
mtd_parts = partition_info32;
if (ts7250_mtd->size >= (128 * 0x100000))
mtd_parts = partition_info128;
mtd_parts_nb = NUM_PARTITIONS;
part_type = "static";
}
/* Register the partitions */
printk(KERN_NOTICE "Using %s partition definition\n", part_type);
add_mtd_partitions(ts7250_mtd, mtd_parts, mtd_parts_nb);
/* Return happy */
return 0;
}
module_init(ts7250_init);
/*
* Clean up routine
*/
static void __exit ts7250_cleanup(void)
{
/* Unregister the device */
del_mtd_device(ts7250_mtd);
/* Free the MTD device structure */
kfree(ts7250_mtd);
}
module_exit(ts7250_cleanup);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Jesse Off <joff@embeddedARM.com>");
MODULE_DESCRIPTION("MTD map driver for Technologic Systems TS-7250 board");