- 根目录:
- drivers
- mtd
- nand
- au1550nd.c
/*
* drivers/mtd/nand/au1550nd.c
*
* Copyright (C) 2004 Embedded Edge, LLC
*
* 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/gpio.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/nand.h>
#include <linux/mtd/partitions.h>
#include <asm/io.h>
#include <asm/mach-au1x00/au1xxx.h>
#include <asm/mach-db1x00/bcsr.h>
/*
* MTD structure for NAND controller
*/
static struct mtd_info *au1550_mtd = NULL;
static void __iomem *p_nand;
static int nand_width = 1; /* default x8 */
static void (*au1550_write_byte)(struct mtd_info *, u_char);
/*
* Define partitions for flash device
*/
static const struct mtd_partition partition_info[] = {
{
.name = "NAND FS 0",
.offset = 0,
.size = 8 * 1024 * 1024},
{
.name = "NAND FS 1",
.offset = MTDPART_OFS_APPEND,
.size = MTDPART_SIZ_FULL}
};
/**
* au_read_byte - read one byte from the chip
* @mtd: MTD device structure
*
* read function for 8bit buswith
*/
static u_char au_read_byte(struct mtd_info *mtd)
{
struct nand_chip *this = mtd->priv;
u_char ret = readb(this->IO_ADDR_R);
au_sync();
return ret;
}
/**
* au_write_byte - write one byte to the chip
* @mtd: MTD device structure
* @byte: pointer to data byte to write
*
* write function for 8it buswith
*/
static void au_write_byte(struct mtd_info *mtd, u_char byte)
{
struct nand_chip *this = mtd->priv;
writeb(byte, this->IO_ADDR_W);
au_sync();
}
/**
* au_read_byte16 - read one byte endianess aware from the chip
* @mtd: MTD device structure
*
* read function for 16bit buswith with
* endianess conversion
*/
static u_char au_read_byte16(struct mtd_info *mtd)
{
struct nand_chip *this = mtd->priv;
u_char ret = (u_char) cpu_to_le16(readw(this->IO_ADDR_R));
au_sync();
return ret;
}
/**
* au_write_byte16 - write one byte endianess aware to the chip
* @mtd: MTD device structure
* @byte: pointer to data byte to write
*
* write function for 16bit buswith with
* endianess conversion
*/
static void au_write_byte16(struct mtd_info *mtd, u_char byte)
{
struct nand_chip *this = mtd->priv;
writew(le16_to_cpu((u16) byte), this->IO_ADDR_W);
au_sync();
}
/**
* au_read_word - read one word from the chip
* @mtd: MTD device structure
*
* read function for 16bit buswith without
* endianess conversion
*/
static u16 au_read_word(struct mtd_info *mtd)
{
struct nand_chip *this = mtd->priv;
u16 ret = readw(this->IO_ADDR_R);
au_sync();
return ret;
}
/**
* au_write_buf - write buffer to chip
* @mtd: MTD device structure
* @buf: data buffer
* @len: number of bytes to write
*
* write function for 8bit buswith
*/
static void au_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
{
int i;
struct nand_chip *this = mtd->priv;
for (i = 0; i < len; i++) {
writeb(buf[i], this->IO_ADDR_W);
au_sync();
}
}
/**
* au_read_buf - read chip data into buffer
* @mtd: MTD device structure
* @buf: buffer to store date
* @len: number of bytes to read
*
* read function for 8bit buswith
*/
static void au_read_buf(struct mtd_info *mtd, u_char *buf, int len)
{
int i;
struct nand_chip *this = mtd->priv;
for (i = 0; i < len; i++) {
buf[i] = readb(this->IO_ADDR_R);
au_sync();
}
}
/**
* au_verify_buf - Verify chip data against buffer
* @mtd: MTD device structure
* @buf: buffer containing the data to compare
* @len: number of bytes to compare
*
* verify function for 8bit buswith
*/
static int au_verify_buf(struct mtd_info *mtd, const u_char *buf, int len)
{
int i;
struct nand_chip *this = mtd->priv;
for (i = 0; i < len; i++) {
if (buf[i] != readb(this->IO_ADDR_R))
return -EFAULT;
au_sync();
}
return 0;
}
/**
* au_write_buf16 - write buffer to chip
* @mtd: MTD device structure
* @buf: data buffer
* @len: number of bytes to write
*
* write function for 16bit buswith
*/
static void au_write_buf16(struct mtd_info *mtd, const u_char *buf, int len)
{
int i;
struct nand_chip *this = mtd->priv;
u16 *p = (u16 *) buf;
len >>= 1;
for (i = 0; i < len; i++) {
writew(p[i], this->IO_ADDR_W);
au_sync();
}
}
/**
* au_read_buf16 - read chip data into buffer
* @mtd: MTD device structure
* @buf: buffer to store date
* @len: number of bytes to read
*
* read function for 16bit buswith
*/
static void au_read_buf16(struct mtd_info *mtd, u_char *buf, int len)
{
int i;
struct nand_chip *this = mtd->priv;
u16 *p = (u16 *) buf;
len >>= 1;
for (i = 0; i < len; i++) {
p[i] = readw(this->IO_ADDR_R);
au_sync();
}
}
/**
* au_verify_buf16 - Verify chip data against buffer
* @mtd: MTD device structure
* @buf: buffer containing the data to compare
* @len: number of bytes to compare
*
* verify function for 16bit buswith
*/
static int au_verify_buf16(struct mtd_info *mtd, const u_char *buf, int len)
{
int i;
struct nand_chip *this = mtd->priv;
u16 *p = (u16 *) buf;
len >>= 1;
for (i = 0; i < len; i++) {
if (p[i] != readw(this->IO_ADDR_R))
return -EFAULT;
au_sync();
}
return 0;
}
/* Select the chip by setting nCE to low */
#define NAND_CTL_SETNCE 1
/* Deselect the chip by setting nCE to high */
#define NAND_CTL_CLRNCE 2
/* Select the command latch by setting CLE to high */
#define NAND_CTL_SETCLE 3
/* Deselect the command latch by setting CLE to low */
#define NAND_CTL_CLRCLE 4
/* Select the address latch by setting ALE to high */
#define NAND_CTL_SETALE 5
/* Deselect the address latch by setting ALE to low */
#define NAND_CTL_CLRALE 6
static void au1550_hwcontrol(struct mtd_info *mtd, int cmd)
{
register struct nand_chip *this = mtd->priv;
switch (cmd) {
case NAND_CTL_SETCLE:
this->IO_ADDR_W = p_nand + MEM_STNAND_CMD;
break;
case NAND_CTL_CLRCLE:
this->IO_ADDR_W = p_nand + MEM_STNAND_DATA;
break;
case NAND_CTL_SETALE:
this->IO_ADDR_W = p_nand + MEM_STNAND_ADDR;
break;
case NAND_CTL_CLRALE:
this->IO_ADDR_W = p_nand + MEM_STNAND_DATA;
/* FIXME: Nobody knows why this is necessary,
* but it works only that way */
udelay(1);
break;
case NAND_CTL_SETNCE:
/* assert (force assert) chip enable */
au_writel((1 << (4 + NAND_CS)), MEM_STNDCTL);
break;
case NAND_CTL_CLRNCE:
/* deassert chip enable */
au_writel(0, MEM_STNDCTL);
break;
}
this->IO_ADDR_R = this->IO_ADDR_W;
/* Drain the writebuffer */
au_sync();
}
int au1550_device_ready(struct mtd_info *mtd)
{
int ret = (au_readl(MEM_STSTAT) & 0x1) ? 1 : 0;
au_sync();
return ret;
}
/**
* au1550_select_chip - control -CE line
* Forbid driving -CE manually permitting the NAND controller to do this.
* Keeping -CE asserted during the whole sector reads interferes with the
* NOR flash and PCMCIA drivers as it causes contention on the static bus.
* We only have to hold -CE low for the NAND read commands since the flash
* chip needs it to be asserted during chip not ready time but the NAND
* controller keeps it released.
*
* @mtd: MTD device structure
* @chip: chipnumber to select, -1 for deselect
*/
static void au1550_select_chip(struct mtd_info *mtd, int chip)
{
}
/**
* au1550_command - Send command to NAND device
* @mtd: MTD device structure
* @command: the command to be sent
* @column: the column address for this command, -1 if none
* @page_addr: the page address for this command, -1 if none
*/
static void au1550_command(struct mtd_info *mtd, unsigned command, int column, int page_addr)
{
register struct nand_chip *this = mtd->priv;
int ce_override = 0, i;
ulong flags;
/* Begin command latch cycle */
au1550_hwcontrol(mtd, NAND_CTL_SETCLE);
/*
* Write out the command to the device.
*/
if (command == NAND_CMD_SEQIN) {
int readcmd;
if (column >= mtd->writesize) {
/* OOB area */
column -= mtd->writesize;
readcmd = NAND_CMD_READOOB;
} else if (column < 256) {
/* First 256 bytes --> READ0 */
readcmd = NAND_CMD_READ0;
} else {
column -= 256;
readcmd = NAND_CMD_READ1;
}
au1550_write_byte(mtd, readcmd);
}
au1550_write_byte(mtd, command);
/* Set ALE and clear CLE to start address cycle */
au1550_hwcontrol(mtd, NAND_CTL_CLRCLE);
if (column != -1 || page_addr != -1) {
au1550_hwcontrol(mtd, NAND_CTL_SETALE);
/* Serially input address */
if (column != -1) {
/* Adjust columns for 16 bit buswidth */
if (this->options & NAND_BUSWIDTH_16)
column >>= 1;
au1550_write_byte(mtd, column);
}
if (page_addr != -1) {
au1550_write_byte(mtd, (u8)(page_addr & 0xff));
if (command == NAND_CMD_READ0 ||
command == NAND_CMD_READ1 ||
command == NAND_CMD_READOOB) {
/*
* NAND controller will release -CE after
* the last address byte is written, so we'll
* have to forcibly assert it. No interrupts
* are allowed while we do this as we don't
* want the NOR flash or PCMCIA drivers to
* steal our precious bytes of data...
*/
ce_override = 1;
local_irq_save(flags);
au1550_hwcontrol(mtd, NAND_CTL_SETNCE);
}
au1550_write_byte(mtd, (u8)(page_addr >> 8));
/* One more address cycle for devices > 32MiB */
if (this->chipsize > (32 << 20))
au1550_write_byte(mtd, (u8)((page_addr >> 16) & 0x0f));
}
/* Latch in address */
au1550_hwcontrol(mtd, NAND_CTL_CLRALE);
}
/*
* Program and erase have their own busy handlers.
* Status and sequential in need no delay.
*/
switch (command) {
case NAND_CMD_PAGEPROG:
case NAND_CMD_ERASE1:
case NAND_CMD_ERASE2:
case NAND_CMD_SEQIN:
case NAND_CMD_STATUS:
return;
case NAND_CMD_RESET:
break;
case NAND_CMD_READ0:
case NAND_CMD_READ1:
case NAND_CMD_READOOB:
/* Check if we're really driving -CE low (just in case) */
if (unlikely(!ce_override))
break;
/* Apply a short delay always to ensure that we do wait tWB. */
ndelay(100);
/* Wait for a chip to become ready... */
for (i = this->chip_delay; !this->dev_ready(mtd) && i > 0; --i)
udelay(1);
/* Release -CE and re-enable interrupts. */
au1550_hwcontrol(mtd, NAND_CTL_CLRNCE);
local_irq_restore(flags);
return;
}
/* Apply this short delay always to ensure that we do wait tWB. */
ndelay(100);
while(!this->dev_ready(mtd));
}
/*
* Main initialization routine
*/
static int __init au1xxx_nand_init(void)
{
struct nand_chip *this;
u16 boot_swapboot = 0; /* default value */
int retval;
u32 mem_staddr;
u32 nand_phys;
/* Allocate memory for MTD device structure and private data */
au1550_mtd = kzalloc(sizeof(struct mtd_info) + sizeof(struct nand_chip), GFP_KERNEL);
if (!au1550_mtd) {
printk("Unable to allocate NAND MTD dev structure.\n");
return -ENOMEM;
}
/* Get pointer to private data */
this = (struct nand_chip *)(&au1550_mtd[1]);
/* Link the private data with the MTD structure */
au1550_mtd->priv = this;
au1550_mtd->owner = THIS_MODULE;
/* MEM_STNDCTL: disable ints, disable nand boot */
au_writel(0, MEM_STNDCTL);
#ifdef CONFIG_MIPS_PB1550
/* set gpio206 high */
gpio_direction_input(206);
boot_swapboot = (au_readl(MEM_STSTAT) & (0x7 << 1)) | ((bcsr_read(BCSR_STATUS) >> 6) & 0x1);
switch (boot_swapboot) {
case 0:
case 2:
case 8:
case 0xC:
case 0xD:
/* x16 NAND Flash */
nand_width = 0;
break;
case 1:
case 9:
case 3:
case 0xE:
case 0xF:
/* x8 NAND Flash */
nand_width = 1;
break;
default:
printk("Pb1550 NAND: bad boot:swap\n");
retval = -EINVAL;
goto outmem;
}
#endif
/* Configure chip-select; normally done by boot code, e.g. YAMON */
#ifdef NAND_STCFG
if (NAND_CS == 0) {
au_writel(NAND_STCFG, MEM_STCFG0);
au_writel(NAND_STTIME, MEM_STTIME0);
au_writel(NAND_STADDR, MEM_STADDR0);
}
if (NAND_CS == 1) {
au_writel(NAND_STCFG, MEM_STCFG1);
au_writel(NAND_STTIME, MEM_STTIME1);
au_writel(NAND_STADDR, MEM_STADDR1);
}
if (NAND_CS == 2) {
au_writel(NAND_STCFG, MEM_STCFG2);
au_writel(NAND_STTIME, MEM_STTIME2);
au_writel(NAND_STADDR, MEM_STADDR2);
}
if (NAND_CS == 3) {
au_writel(NAND_STCFG, MEM_STCFG3);
au_writel(NAND_STTIME, MEM_STTIME3);
au_writel(NAND_STADDR, MEM_STADDR3);
}
#endif
/* Locate NAND chip-select in order to determine NAND phys address */
mem_staddr = 0x00000000;
if (((au_readl(MEM_STCFG0) & 0x7) == 0x5) && (NAND_CS == 0))
mem_staddr = au_readl(MEM_STADDR0);
else if (((au_readl(MEM_STCFG1) & 0x7) == 0x5) && (NAND_CS == 1))
mem_staddr = au_readl(MEM_STADDR1);
else if (((au_readl(MEM_STCFG2) & 0x7) == 0x5) && (NAND_CS == 2))
mem_staddr = au_readl(MEM_STADDR2);
else if (((au_readl(MEM_STCFG3) & 0x7) == 0x5) && (NAND_CS == 3))
mem_staddr = au_readl(MEM_STADDR3);
if (mem_staddr == 0x00000000) {
printk("Au1xxx NAND: ERROR WITH NAND CHIP-SELECT\n");
kfree(au1550_mtd);
return 1;
}
nand_phys = (mem_staddr << 4) & 0xFFFC0000;
p_nand = ioremap(nand_phys, 0x1000);
/* make controller and MTD agree */
if (NAND_CS == 0)
nand_width = au_readl(MEM_STCFG0) & (1 << 22);
if (NAND_CS == 1)
nand_width = au_readl(MEM_STCFG1) & (1 << 22);
if (NAND_CS == 2)
nand_width = au_readl(MEM_STCFG2) & (1 << 22);
if (NAND_CS == 3)
nand_width = au_readl(MEM_STCFG3) & (1 << 22);
/* Set address of hardware control function */
this->dev_ready = au1550_device_ready;
this->select_chip = au1550_select_chip;
this->cmdfunc = au1550_command;
/* 30 us command delay time */
this->chip_delay = 30;
this->ecc.mode = NAND_ECC_SOFT;
this->options = NAND_NO_AUTOINCR;
if (!nand_width)
this->options |= NAND_BUSWIDTH_16;
this->read_byte = (!nand_width) ? au_read_byte16 : au_read_byte;
au1550_write_byte = (!nand_width) ? au_write_byte16 : au_write_byte;
this->read_word = au_read_word;
this->write_buf = (!nand_width) ? au_write_buf16 : au_write_buf;
this->read_buf = (!nand_width) ? au_read_buf16 : au_read_buf;
this->verify_buf = (!nand_width) ? au_verify_buf16 : au_verify_buf;
/* Scan to find existence of the device */
if (nand_scan(au1550_mtd, 1)) {
retval = -ENXIO;
goto outio;
}
/* Register the partitions */
mtd_device_register(au1550_mtd, partition_info,
ARRAY_SIZE(partition_info));
return 0;
outio:
iounmap(p_nand);
outmem:
kfree(au1550_mtd);
return retval;
}
module_init(au1xxx_nand_init);
/*
* Clean up routine
*/
static void __exit au1550_cleanup(void)
{
/* Release resources, unregister device */
nand_release(au1550_mtd);
/* Free the MTD device structure */
kfree(au1550_mtd);
/* Unmap */
iounmap(p_nand);
}
module_exit(au1550_cleanup);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Embedded Edge, LLC");
MODULE_DESCRIPTION("Board-specific glue layer for NAND flash on Pb1550 board");