Openwrt/target/linux/olpc/files/drivers/mtd/onenand/onenand_sim.c
John Crispin 42fc624cba cleaning up olpc patch 1
SVN-Revision: 10060
2007-12-30 17:38:08 +00:00

496 lines
12 KiB
C

/*
* linux/drivers/mtd/onenand/onenand_sim.c
*
* The OneNAND simulator
*
* Copyright © 2005-2007 Samsung Electronics
* Kyungmin Park <kyungmin.park@samsung.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/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/vmalloc.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
#include <linux/mtd/onenand.h>
#include <linux/io.h>
#ifndef CONFIG_ONENAND_SIM_MANUFACTURER
#define CONFIG_ONENAND_SIM_MANUFACTURER 0xec
#endif
#ifndef CONFIG_ONENAND_SIM_DEVICE_ID
#define CONFIG_ONENAND_SIM_DEVICE_ID 0x04
#endif
#ifndef CONFIG_ONENAND_SIM_VERSION_ID
#define CONFIG_ONENAND_SIM_VERSION_ID 0x1e
#endif
static int manuf_id = CONFIG_ONENAND_SIM_MANUFACTURER;
static int device_id = CONFIG_ONENAND_SIM_DEVICE_ID;
static int version_id = CONFIG_ONENAND_SIM_VERSION_ID;
struct onenand_flash {
void __iomem *base;
void __iomem *data;
};
#define ONENAND_CORE(flash) (flash->data)
#define ONENAND_CORE_SPARE(flash, this, offset) \
((flash->data) + (this->chipsize) + (offset >> 5))
#define ONENAND_MAIN_AREA(this, offset) \
(this->base + ONENAND_DATARAM + offset)
#define ONENAND_SPARE_AREA(this, offset) \
(this->base + ONENAND_SPARERAM + offset)
#define ONENAND_GET_WP_STATUS(this) \
(readw(this->base + ONENAND_REG_WP_STATUS))
#define ONENAND_SET_WP_STATUS(v, this) \
(writew(v, this->base + ONENAND_REG_WP_STATUS))
/* It has all 0xff chars */
#define MAX_ONENAND_PAGESIZE (2048 + 64)
static unsigned char *ffchars;
static struct mtd_partition os_partitions[] = {
{
.name = "OneNAND simulator partition",
.offset = 0,
.size = MTDPART_SIZ_FULL,
},
};
/*
* OneNAND simulator mtd
*/
struct onenand_info {
struct mtd_info mtd;
struct mtd_partition *parts;
struct onenand_chip onenand;
struct onenand_flash flash;
};
struct onenand_info *info;
#define DPRINTK(format, args...) \
do { \
printk(KERN_DEBUG "%s[%d]: " format "\n", __func__, \
__LINE__, ##args); \
} while (0)
/**
* onenand_lock_handle - Handle Lock scheme
* @param this OneNAND device structure
* @param cmd The command to be sent
*
* Send lock command to OneNAND device.
* The lock scheme is depends on chip type.
*/
static void onenand_lock_handle(struct onenand_chip *this, int cmd)
{
int block_lock_scheme;
int status;
status = ONENAND_GET_WP_STATUS(this);
block_lock_scheme = !(this->options & ONENAND_HAS_CONT_LOCK);
switch (cmd) {
case ONENAND_CMD_UNLOCK:
if (block_lock_scheme)
ONENAND_SET_WP_STATUS(ONENAND_WP_US, this);
else
ONENAND_SET_WP_STATUS(status | ONENAND_WP_US, this);
break;
case ONENAND_CMD_LOCK:
if (block_lock_scheme)
ONENAND_SET_WP_STATUS(ONENAND_WP_LS, this);
else
ONENAND_SET_WP_STATUS(status | ONENAND_WP_LS, this);
break;
case ONENAND_CMD_LOCK_TIGHT:
if (block_lock_scheme)
ONENAND_SET_WP_STATUS(ONENAND_WP_LTS, this);
else
ONENAND_SET_WP_STATUS(status | ONENAND_WP_LTS, this);
break;
default:
break;
}
}
/**
* onenand_bootram_handle - Handle BootRAM area
* @param this OneNAND device structure
* @param cmd The command to be sent
*
* Emulate BootRAM area. It is possible to do basic operation using BootRAM.
*/
static void onenand_bootram_handle(struct onenand_chip *this, int cmd)
{
switch (cmd) {
case ONENAND_CMD_READID:
writew(manuf_id, this->base);
writew(device_id, this->base + 2);
writew(version_id, this->base + 4);
break;
default:
/* REVIST: Handle other commands */
break;
}
}
/**
* onenand_update_interrupt - Set interrupt register
* @param this OneNAND device structure
* @param cmd The command to be sent
*
* Update interrupt register. The status is depends on command.
*/
static void onenand_update_interrupt(struct onenand_chip *this, int cmd)
{
int interrupt = ONENAND_INT_MASTER;
switch (cmd) {
case ONENAND_CMD_READ:
case ONENAND_CMD_READOOB:
interrupt |= ONENAND_INT_READ;
break;
case ONENAND_CMD_PROG:
case ONENAND_CMD_PROGOOB:
interrupt |= ONENAND_INT_WRITE;
break;
case ONENAND_CMD_ERASE:
interrupt |= ONENAND_INT_ERASE;
break;
case ONENAND_CMD_RESET:
interrupt |= ONENAND_INT_RESET;
break;
default:
break;
}
writew(interrupt, this->base + ONENAND_REG_INTERRUPT);
}
/**
* onenand_check_overwrite - Check over-write if happend
* @param dest The destination pointer
* @param src The source pointer
* @param count The length to be check
* @return 0 on same, otherwise 1
*
* Compare the source with destination
*/
static int onenand_check_overwrite(void *dest, void *src, size_t count)
{
unsigned int *s = (unsigned int *) src;
unsigned int *d = (unsigned int *) dest;
int i;
count >>= 2;
for (i = 0; i < count; i++)
if ((*s++ ^ *d++) != 0)
return 1;
return 0;
}
/**
* onenand_data_handle - Handle OneNAND Core and DataRAM
* @param this OneNAND device structure
* @param cmd The command to be sent
* @param dataram Which dataram used
* @param offset The offset to OneNAND Core
*
* Copy data from OneNAND Core to DataRAM (read)
* Copy data from DataRAM to OneNAND Core (write)
* Erase the OneNAND Core (erase)
*/
static void onenand_data_handle(struct onenand_chip *this, int cmd,
int dataram, unsigned int offset)
{
struct mtd_info *mtd = &info->mtd;
struct onenand_flash *flash = this->priv;
int main_offset, spare_offset;
void __iomem *src;
void __iomem *dest;
unsigned int i;
if (dataram) {
main_offset = mtd->writesize;
spare_offset = mtd->oobsize;
} else {
main_offset = 0;
spare_offset = 0;
}
switch (cmd) {
case ONENAND_CMD_READ:
src = ONENAND_CORE(flash) + offset;
dest = ONENAND_MAIN_AREA(this, main_offset);
memcpy(dest, src, mtd->writesize);
/* Fall through */
case ONENAND_CMD_READOOB:
src = ONENAND_CORE_SPARE(flash, this, offset);
dest = ONENAND_SPARE_AREA(this, spare_offset);
memcpy(dest, src, mtd->oobsize);
break;
case ONENAND_CMD_PROG:
src = ONENAND_MAIN_AREA(this, main_offset);
dest = ONENAND_CORE(flash) + offset;
/* To handle partial write */
for (i = 0; i < (1 << mtd->subpage_sft); i++) {
int off = i * this->subpagesize;
if (!memcmp(src + off, ffchars, this->subpagesize))
continue;
if (memcmp(dest + off, ffchars, this->subpagesize) &&
onenand_check_overwrite(dest + off, src + off, this->subpagesize))
printk(KERN_ERR "over-write happend at 0x%08x\n", offset);
memcpy(dest + off, src + off, this->subpagesize);
}
/* Fall through */
case ONENAND_CMD_PROGOOB:
src = ONENAND_SPARE_AREA(this, spare_offset);
/* Check all data is 0xff chars */
if (!memcmp(src, ffchars, mtd->oobsize))
break;
dest = ONENAND_CORE_SPARE(flash, this, offset);
if (memcmp(dest, ffchars, mtd->oobsize) &&
onenand_check_overwrite(dest, src, mtd->oobsize))
printk(KERN_ERR "OOB: over-write happend at 0x%08x\n",
offset);
memcpy(dest, src, mtd->oobsize);
break;
case ONENAND_CMD_ERASE:
memset(ONENAND_CORE(flash) + offset, 0xff, mtd->erasesize);
memset(ONENAND_CORE_SPARE(flash, this, offset), 0xff,
(mtd->erasesize >> 5));
break;
default:
break;
}
}
/**
* onenand_command_handle - Handle command
* @param this OneNAND device structure
* @param cmd The command to be sent
*
* Emulate OneNAND command.
*/
static void onenand_command_handle(struct onenand_chip *this, int cmd)
{
unsigned long offset = 0;
int block = -1, page = -1, bufferram = -1;
int dataram = 0;
switch (cmd) {
case ONENAND_CMD_UNLOCK:
case ONENAND_CMD_LOCK:
case ONENAND_CMD_LOCK_TIGHT:
case ONENAND_CMD_UNLOCK_ALL:
onenand_lock_handle(this, cmd);
break;
case ONENAND_CMD_BUFFERRAM:
/* Do nothing */
return;
default:
block = (int) readw(this->base + ONENAND_REG_START_ADDRESS1);
if (block & (1 << ONENAND_DDP_SHIFT)) {
block &= ~(1 << ONENAND_DDP_SHIFT);
/* The half of chip block */
block += this->chipsize >> (this->erase_shift + 1);
}
if (cmd == ONENAND_CMD_ERASE)
break;
page = (int) readw(this->base + ONENAND_REG_START_ADDRESS8);
page = (page >> ONENAND_FPA_SHIFT);
bufferram = (int) readw(this->base + ONENAND_REG_START_BUFFER);
bufferram >>= ONENAND_BSA_SHIFT;
bufferram &= ONENAND_BSA_DATARAM1;
dataram = (bufferram == ONENAND_BSA_DATARAM1) ? 1 : 0;
break;
}
if (block != -1)
offset += block << this->erase_shift;
if (page != -1)
offset += page << this->page_shift;
onenand_data_handle(this, cmd, dataram, offset);
onenand_update_interrupt(this, cmd);
}
/**
* onenand_writew - [OneNAND Interface] Emulate write operation
* @param value value to write
* @param addr address to write
*
* Write OneNAND register with value
*/
static void onenand_writew(unsigned short value, void __iomem * addr)
{
struct onenand_chip *this = info->mtd.priv;
/* BootRAM handling */
if (addr < this->base + ONENAND_DATARAM) {
onenand_bootram_handle(this, value);
return;
}
/* Command handling */
if (addr == this->base + ONENAND_REG_COMMAND)
onenand_command_handle(this, value);
writew(value, addr);
}
/**
* flash_init - Initialize OneNAND simulator
* @param flash OneNAND simulaotr data strucutres
*
* Initialize OneNAND simulator.
*/
static int __init flash_init(struct onenand_flash *flash)
{
int density, size;
int buffer_size;
flash->base = kzalloc(131072, GFP_KERNEL);
if (!flash->base) {
printk(KERN_ERR "Unable to allocate base address.\n");
return -ENOMEM;
}
density = device_id >> ONENAND_DEVICE_DENSITY_SHIFT;
size = ((16 << 20) << density);
ONENAND_CORE(flash) = vmalloc(size + (size >> 5));
if (!ONENAND_CORE(flash)) {
printk(KERN_ERR "Unable to allocate nand core address.\n");
kfree(flash->base);
return -ENOMEM;
}
memset(ONENAND_CORE(flash), 0xff, size + (size >> 5));
/* Setup registers */
writew(manuf_id, flash->base + ONENAND_REG_MANUFACTURER_ID);
writew(device_id, flash->base + ONENAND_REG_DEVICE_ID);
writew(version_id, flash->base + ONENAND_REG_VERSION_ID);
if (density < 2)
buffer_size = 0x0400; /* 1KiB page */
else
buffer_size = 0x0800; /* 2KiB page */
writew(buffer_size, flash->base + ONENAND_REG_DATA_BUFFER_SIZE);
return 0;
}
/**
* flash_exit - Clean up OneNAND simulator
* @param flash OneNAND simulaotr data strucutres
*
* Clean up OneNAND simulator.
*/
static void flash_exit(struct onenand_flash *flash)
{
vfree(ONENAND_CORE(flash));
kfree(flash->base);
kfree(flash);
}
static int __init onenand_sim_init(void)
{
/* Allocate all 0xff chars pointer */
ffchars = kmalloc(MAX_ONENAND_PAGESIZE, GFP_KERNEL);
if (!ffchars) {
printk(KERN_ERR "Unable to allocate ff chars.\n");
return -ENOMEM;
}
memset(ffchars, 0xff, MAX_ONENAND_PAGESIZE);
/* Allocate OneNAND simulator mtd pointer */
info = kzalloc(sizeof(struct onenand_info), GFP_KERNEL);
if (!info) {
printk(KERN_ERR "Unable to allocate core structures.\n");
kfree(ffchars);
return -ENOMEM;
}
/* Override write_word function */
info->onenand.write_word = onenand_writew;
if (flash_init(&info->flash)) {
printk(KERN_ERR "Unable to allocat flash.\n");
kfree(ffchars);
kfree(info);
return -ENOMEM;
}
info->parts = os_partitions;
info->onenand.base = info->flash.base;
info->onenand.priv = &info->flash;
info->mtd.name = "OneNAND simulator";
info->mtd.priv = &info->onenand;
info->mtd.owner = THIS_MODULE;
if (onenand_scan(&info->mtd, 1)) {
flash_exit(&info->flash);
kfree(ffchars);
kfree(info);
return -ENXIO;
}
add_mtd_partitions(&info->mtd, info->parts, ARRAY_SIZE(os_partitions));
return 0;
}
static void __exit onenand_sim_exit(void)
{
struct onenand_chip *this = info->mtd.priv;
struct onenand_flash *flash = this->priv;
onenand_release(&info->mtd);
flash_exit(flash);
kfree(ffchars);
kfree(info);
}
module_init(onenand_sim_init);
module_exit(onenand_sim_exit);
MODULE_AUTHOR("Kyungmin Park <kyungmin.park@samsung.com>");
MODULE_DESCRIPTION("The OneNAND flash simulator");
MODULE_LICENSE("GPL");