android_kernel_xiaomi_sm8350/drivers/mtd/nand/spia.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

179 lines
4.3 KiB
C

/*
* drivers/mtd/nand/spia.c
*
* Copyright (C) 2000 Steven J. Hill (sjhill@realitydiluted.com)
*
*
* 10-29-2001 TG change to support hardwarespecific access
* to controllines (due to change in nand.c)
* page_cache added
*
* $Id: spia.c,v 1.25 2005/11/07 11:14:31 gleixner 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
* SPIA board which utilizes the Toshiba TC58V64AFT part. This is
* a 64Mibit (8MiB x 8 bits) NAND flash device.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/nand.h>
#include <linux/mtd/partitions.h>
#include <asm/io.h>
/*
* MTD structure for SPIA board
*/
static struct mtd_info *spia_mtd = NULL;
/*
* Values specific to the SPIA board (used with EP7212 processor)
*/
#define SPIA_IO_BASE 0xd0000000 /* Start of EP7212 IO address space */
#define SPIA_FIO_BASE 0xf0000000 /* Address where flash is mapped */
#define SPIA_PEDR 0x0080 /*
* IO offset to Port E data register
* where the CLE, ALE and NCE pins
* are wired to.
*/
#define SPIA_PEDDR 0x00c0 /*
* IO offset to Port E data direction
* register so we can control the IO
* lines.
*/
/*
* Module stuff
*/
static int spia_io_base = SPIA_IO_BASE;
static int spia_fio_base = SPIA_FIO_BASE;
static int spia_pedr = SPIA_PEDR;
static int spia_peddr = SPIA_PEDDR;
module_param(spia_io_base, int, 0);
module_param(spia_fio_base, int, 0);
module_param(spia_pedr, int, 0);
module_param(spia_peddr, int, 0);
/*
* Define partitions for flash device
*/
static const struct mtd_partition partition_info[] = {
{
.name = "SPIA flash partition 1",
.offset = 0,
.size = 2 * 1024 * 1024},
{
.name = "SPIA flash partition 2",
.offset = 2 * 1024 * 1024,
.size = 6 * 1024 * 1024}
};
#define NUM_PARTITIONS 2
/*
* hardware specific access to control-lines
*
* ctrl:
* NAND_CNE: bit 0 -> bit 2
* NAND_CLE: bit 1 -> bit 0
* NAND_ALE: bit 2 -> bit 1
*/
static void spia_hwcontrol(struct mtd_info *mtd, int cmd)
{
struct nand_chip *chip = mtd->priv;
if (ctrl & NAND_CTRL_CHANGE) {
void __iomem *addr = spia_io_base + spia_pedr;
unsigned char bits;
bits = (ctrl & NAND_CNE) << 2;
bits |= (ctrl & NAND_CLE | NAND_ALE) >> 1;
writeb((readb(addr) & ~0x7) | bits, addr);
}
if (cmd != NAND_CMD_NONE)
writeb(cmd, chip->IO_ADDR_W);
}
/*
* Main initialization routine
*/
static int __init spia_init(void)
{
struct nand_chip *this;
/* Allocate memory for MTD device structure and private data */
spia_mtd = kmalloc(sizeof(struct mtd_info) + sizeof(struct nand_chip), GFP_KERNEL);
if (!spia_mtd) {
printk("Unable to allocate SPIA NAND MTD device structure.\n");
return -ENOMEM;
}
/* Get pointer to private data */
this = (struct nand_chip *)(&spia_mtd[1]);
/* Initialize structures */
memset(spia_mtd, 0, sizeof(struct mtd_info));
memset(this, 0, sizeof(struct nand_chip));
/* Link the private data with the MTD structure */
spia_mtd->priv = this;
spia_mtd->owner = THIS_MODULE;
/*
* Set GPIO Port E control register so that the pins are configured
* to be outputs for controlling the NAND flash.
*/
(*(volatile unsigned char *)(spia_io_base + spia_peddr)) = 0x07;
/* Set address of NAND IO lines */
this->IO_ADDR_R = (void __iomem *)spia_fio_base;
this->IO_ADDR_W = (void __iomem *)spia_fio_base;
/* Set address of hardware control function */
this->cmd_ctrl = spia_hwcontrol;
/* 15 us command delay time */
this->chip_delay = 15;
/* Scan to find existence of the device */
if (nand_scan(spia_mtd, 1)) {
kfree(spia_mtd);
return -ENXIO;
}
/* Register the partitions */
add_mtd_partitions(spia_mtd, partition_info, NUM_PARTITIONS);
/* Return happy */
return 0;
}
module_init(spia_init);
/*
* Clean up routine
*/
static void __exit spia_cleanup(void)
{
/* Release resources, unregister device */
nand_release(spia_mtd);
/* Free the MTD device structure */
kfree(spia_mtd);
}
module_exit(spia_cleanup);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Steven J. Hill <sjhill@realitydiluted.com");
MODULE_DESCRIPTION("Board-specific glue layer for NAND flash on SPIA board");