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linux/drivers/mtd/nand/s3c2410.c
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2 
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

705 lines
16 KiB
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/* linux/drivers/mtd/nand/s3c2410.c
*
* Copyright (c) 2004 Simtec Electronics
* Ben Dooks <ben@simtec.co.uk>
*
* Samsung S3C2410 NAND driver
*
* Changelog:
* 21-Sep-2004 BJD Initial version
* 23-Sep-2004 BJD Mulitple device support
* 28-Sep-2004 BJD Fixed ECC placement for Hardware mode
* 12-Oct-2004 BJD Fixed errors in use of platform data
*
* $Id: s3c2410.c,v 1.7 2005/01/05 18:05:14 dwmw2 Exp $
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <config/mtd/nand/s3c2410/hwecc.h>
#include <config/mtd/nand/s3c2410/debug.h>
#ifdef CONFIG_MTD_NAND_S3C2410_DEBUG
#define DEBUG
#endif
#include <linux/module.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/ioport.h>
#include <linux/device.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/nand.h>
#include <linux/mtd/nand_ecc.h>
#include <linux/mtd/partitions.h>
#include <asm/io.h>
#include <asm/mach-types.h>
#include <asm/hardware/clock.h>
#include <asm/arch/regs-nand.h>
#include <asm/arch/nand.h>
#define PFX "s3c2410-nand: "
#ifdef CONFIG_MTD_NAND_S3C2410_HWECC
static int hardware_ecc = 1;
#else
static int hardware_ecc = 0;
#endif
/* new oob placement block for use with hardware ecc generation
*/
static struct nand_oobinfo nand_hw_eccoob = {
.useecc = MTD_NANDECC_AUTOPLACE,
.eccbytes = 3,
.eccpos = {0, 1, 2 },
.oobfree = { {8, 8} }
};
/* controller and mtd information */
struct s3c2410_nand_info;
struct s3c2410_nand_mtd {
struct mtd_info mtd;
struct nand_chip chip;
struct s3c2410_nand_set *set;
struct s3c2410_nand_info *info;
int scan_res;
};
/* overview of the s3c2410 nand state */
struct s3c2410_nand_info {
/* mtd info */
struct nand_hw_control controller;
struct s3c2410_nand_mtd *mtds;
struct s3c2410_platform_nand *platform;
/* device info */
struct device *device;
struct resource *area;
struct clk *clk;
void *regs;
int mtd_count;
};
/* conversion functions */
static struct s3c2410_nand_mtd *s3c2410_nand_mtd_toours(struct mtd_info *mtd)
{
return container_of(mtd, struct s3c2410_nand_mtd, mtd);
}
static struct s3c2410_nand_info *s3c2410_nand_mtd_toinfo(struct mtd_info *mtd)
{
return s3c2410_nand_mtd_toours(mtd)->info;
}
static struct s3c2410_nand_info *to_nand_info(struct device *dev)
{
return dev_get_drvdata(dev);
}
static struct s3c2410_platform_nand *to_nand_plat(struct device *dev)
{
return dev->platform_data;
}
/* timing calculations */
#define NS_IN_KHZ 10000000
static int s3c2410_nand_calc_rate(int wanted, unsigned long clk, int max)
{
int result;
result = (wanted * NS_IN_KHZ) / clk;
result++;
pr_debug("result %d from %ld, %d\n", result, clk, wanted);
if (result > max) {
printk("%d ns is too big for current clock rate %ld\n",
wanted, clk);
return -1;
}
if (result < 1)
result = 1;
return result;
}
#define to_ns(ticks,clk) (((clk) * (ticks)) / NS_IN_KHZ)
/* controller setup */
static int s3c2410_nand_inithw(struct s3c2410_nand_info *info,
struct device *dev)
{
struct s3c2410_platform_nand *plat = to_nand_plat(dev);
unsigned int tacls, twrph0, twrph1;
unsigned long clkrate = clk_get_rate(info->clk);
unsigned long cfg;
/* calculate the timing information for the controller */
if (plat != NULL) {
tacls = s3c2410_nand_calc_rate(plat->tacls, clkrate, 8);
twrph0 = s3c2410_nand_calc_rate(plat->twrph0, clkrate, 8);
twrph1 = s3c2410_nand_calc_rate(plat->twrph1, clkrate, 8);
} else {
/* default timings */
tacls = 8;
twrph0 = 8;
twrph1 = 8;
}
if (tacls < 0 || twrph0 < 0 || twrph1 < 0) {
printk(KERN_ERR PFX "cannot get timings suitable for board\n");
return -EINVAL;
}
printk(KERN_INFO PFX "timing: Tacls %ldns, Twrph0 %ldns, Twrph1 %ldns\n",
to_ns(tacls, clkrate),
to_ns(twrph0, clkrate),
to_ns(twrph1, clkrate));
cfg = S3C2410_NFCONF_EN;
cfg |= S3C2410_NFCONF_TACLS(tacls-1);
cfg |= S3C2410_NFCONF_TWRPH0(twrph0-1);
cfg |= S3C2410_NFCONF_TWRPH1(twrph1-1);
pr_debug(PFX "NF_CONF is 0x%lx\n", cfg);
writel(cfg, info->regs + S3C2410_NFCONF);
return 0;
}
/* select chip */
static void s3c2410_nand_select_chip(struct mtd_info *mtd, int chip)
{
struct s3c2410_nand_info *info;
struct s3c2410_nand_mtd *nmtd;
struct nand_chip *this = mtd->priv;
unsigned long cur;
nmtd = this->priv;
info = nmtd->info;
cur = readl(info->regs + S3C2410_NFCONF);
if (chip == -1) {
cur |= S3C2410_NFCONF_nFCE;
} else {
if (chip > nmtd->set->nr_chips) {
printk(KERN_ERR PFX "chip %d out of range\n", chip);
return;
}
if (info->platform != NULL) {
if (info->platform->select_chip != NULL)
(info->platform->select_chip)(nmtd->set, chip);
}
cur &= ~S3C2410_NFCONF_nFCE;
}
writel(cur, info->regs + S3C2410_NFCONF);
}
/* command and control functions */
static void s3c2410_nand_hwcontrol(struct mtd_info *mtd, int cmd)
{
struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
unsigned long cur;
switch (cmd) {
case NAND_CTL_SETNCE:
cur = readl(info->regs + S3C2410_NFCONF);
cur &= ~S3C2410_NFCONF_nFCE;
writel(cur, info->regs + S3C2410_NFCONF);
break;
case NAND_CTL_CLRNCE:
cur = readl(info->regs + S3C2410_NFCONF);
cur |= S3C2410_NFCONF_nFCE;
writel(cur, info->regs + S3C2410_NFCONF);
break;
/* we don't need to implement these */
case NAND_CTL_SETCLE:
case NAND_CTL_CLRCLE:
case NAND_CTL_SETALE:
case NAND_CTL_CLRALE:
pr_debug(PFX "s3c2410_nand_hwcontrol(%d) unusedn", cmd);
break;
}
}
/* s3c2410_nand_command
*
* This function implements sending commands and the relevant address
* information to the chip, via the hardware controller. Since the
* S3C2410 generates the correct ALE/CLE signaling automatically, we
* do not need to use hwcontrol.
*/
static void s3c2410_nand_command (struct mtd_info *mtd, unsigned command,
int column, int page_addr)
{
register struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
register struct nand_chip *this = mtd->priv;
/*
* Write out the command to the device.
*/
if (command == NAND_CMD_SEQIN) {
int readcmd;
if (column >= mtd->oobblock) {
/* OOB area */
column -= mtd->oobblock;
readcmd = NAND_CMD_READOOB;
} else if (column < 256) {
/* First 256 bytes --> READ0 */
readcmd = NAND_CMD_READ0;
} else {
column -= 256;
readcmd = NAND_CMD_READ1;
}
writeb(readcmd, info->regs + S3C2410_NFCMD);
}
writeb(command, info->regs + S3C2410_NFCMD);
/* Set ALE and clear CLE to start address cycle */
if (column != -1 || page_addr != -1) {
/* Serially input address */
if (column != -1) {
/* Adjust columns for 16 bit buswidth */
if (this->options & NAND_BUSWIDTH_16)
column >>= 1;
writeb(column, info->regs + S3C2410_NFADDR);
}
if (page_addr != -1) {
writeb((unsigned char) (page_addr), info->regs + S3C2410_NFADDR);
writeb((unsigned char) (page_addr >> 8), info->regs + S3C2410_NFADDR);
/* One more address cycle for higher density devices */
if (this->chipsize & 0x0c000000)
writeb((unsigned char) ((page_addr >> 16) & 0x0f),
info->regs + S3C2410_NFADDR);
}
/* Latch in address */
}
/*
* program and erase have their own busy handlers
* status and sequential in needs 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:
if (this->dev_ready)
break;
udelay(this->chip_delay);
writeb(NAND_CMD_STATUS, info->regs + S3C2410_NFCMD);
while ( !(this->read_byte(mtd) & 0x40));
return;
/* This applies to read commands */
default:
/*
* If we don't have access to the busy pin, we apply the given
* command delay
*/
if (!this->dev_ready) {
udelay (this->chip_delay);
return;
}
}
/* Apply this short delay always to ensure that we do wait tWB in
* any case on any machine. */
ndelay (100);
/* wait until command is processed */
while (!this->dev_ready(mtd));
}
/* s3c2410_nand_devready()
*
* returns 0 if the nand is busy, 1 if it is ready
*/
static int s3c2410_nand_devready(struct mtd_info *mtd)
{
struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
return readb(info->regs + S3C2410_NFSTAT) & S3C2410_NFSTAT_BUSY;
}
/* ECC handling functions */
static int s3c2410_nand_correct_data(struct mtd_info *mtd, u_char *dat,
u_char *read_ecc, u_char *calc_ecc)
{
pr_debug("s3c2410_nand_correct_data(%p,%p,%p,%p)\n",
mtd, dat, read_ecc, calc_ecc);
pr_debug("eccs: read %02x,%02x,%02x vs calc %02x,%02x,%02x\n",
read_ecc[0], read_ecc[1], read_ecc[2],
calc_ecc[0], calc_ecc[1], calc_ecc[2]);
if (read_ecc[0] == calc_ecc[0] &&
read_ecc[1] == calc_ecc[1] &&
read_ecc[2] == calc_ecc[2])
return 0;
/* we curently have no method for correcting the error */
return -1;
}
static void s3c2410_nand_enable_hwecc(struct mtd_info *mtd, int mode)
{
struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
unsigned long ctrl;
ctrl = readl(info->regs + S3C2410_NFCONF);
ctrl |= S3C2410_NFCONF_INITECC;
writel(ctrl, info->regs + S3C2410_NFCONF);
}
static int s3c2410_nand_calculate_ecc(struct mtd_info *mtd,
const u_char *dat, u_char *ecc_code)
{
struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
ecc_code[0] = readb(info->regs + S3C2410_NFECC + 0);
ecc_code[1] = readb(info->regs + S3C2410_NFECC + 1);
ecc_code[2] = readb(info->regs + S3C2410_NFECC + 2);
pr_debug("calculate_ecc: returning ecc %02x,%02x,%02x\n",
ecc_code[0], ecc_code[1], ecc_code[2]);
return 0;
}
/* over-ride the standard functions for a little more speed? */
static void s3c2410_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
{
struct nand_chip *this = mtd->priv;
readsb(this->IO_ADDR_R, buf, len);
}
static void s3c2410_nand_write_buf(struct mtd_info *mtd,
const u_char *buf, int len)
{
struct nand_chip *this = mtd->priv;
writesb(this->IO_ADDR_W, buf, len);
}
/* device management functions */
static int s3c2410_nand_remove(struct device *dev)
{
struct s3c2410_nand_info *info = to_nand_info(dev);
dev_set_drvdata(dev, NULL);
if (info == NULL)
return 0;
/* first thing we need to do is release all our mtds
* and their partitions, then go through freeing the
* resources used
*/
if (info->mtds != NULL) {
struct s3c2410_nand_mtd *ptr = info->mtds;
int mtdno;
for (mtdno = 0; mtdno < info->mtd_count; mtdno++, ptr++) {
pr_debug("releasing mtd %d (%p)\n", mtdno, ptr);
nand_release(&ptr->mtd);
}
kfree(info->mtds);
}
/* free the common resources */
if (info->clk != NULL && !IS_ERR(info->clk)) {
clk_disable(info->clk);
clk_unuse(info->clk);
clk_put(info->clk);
}
if (info->regs != NULL) {
iounmap(info->regs);
info->regs = NULL;
}
if (info->area != NULL) {
release_resource(info->area);
kfree(info->area);
info->area = NULL;
}
kfree(info);
return 0;
}
#ifdef CONFIG_MTD_PARTITIONS
static int s3c2410_nand_add_partition(struct s3c2410_nand_info *info,
struct s3c2410_nand_mtd *mtd,
struct s3c2410_nand_set *set)
{
if (set == NULL)
return add_mtd_device(&mtd->mtd);
if (set->nr_partitions > 0 && set->partitions != NULL) {
return add_mtd_partitions(&mtd->mtd,
set->partitions,
set->nr_partitions);
}
return add_mtd_device(&mtd->mtd);
}
#else
static int s3c2410_nand_add_partition(struct s3c2410_nand_info *info,
struct s3c2410_nand_mtd *mtd,
struct s3c2410_nand_set *set)
{
return add_mtd_device(&mtd->mtd);
}
#endif
/* s3c2410_nand_init_chip
*
* init a single instance of an chip
*/
static void s3c2410_nand_init_chip(struct s3c2410_nand_info *info,
struct s3c2410_nand_mtd *nmtd,
struct s3c2410_nand_set *set)
{
struct nand_chip *chip = &nmtd->chip;
chip->IO_ADDR_R = (char *)info->regs + S3C2410_NFDATA;
chip->IO_ADDR_W = (char *)info->regs + S3C2410_NFDATA;
chip->hwcontrol = s3c2410_nand_hwcontrol;
chip->dev_ready = s3c2410_nand_devready;
chip->cmdfunc = s3c2410_nand_command;
chip->write_buf = s3c2410_nand_write_buf;
chip->read_buf = s3c2410_nand_read_buf;
chip->select_chip = s3c2410_nand_select_chip;
chip->chip_delay = 50;
chip->priv = nmtd;
chip->options = 0;
chip->controller = &info->controller;
nmtd->info = info;
nmtd->mtd.priv = chip;
nmtd->set = set;
if (hardware_ecc) {
chip->correct_data = s3c2410_nand_correct_data;
chip->enable_hwecc = s3c2410_nand_enable_hwecc;
chip->calculate_ecc = s3c2410_nand_calculate_ecc;
chip->eccmode = NAND_ECC_HW3_512;
chip->autooob = &nand_hw_eccoob;
} else {
chip->eccmode = NAND_ECC_SOFT;
}
}
/* s3c2410_nand_probe
*
* called by device layer when it finds a device matching
* one our driver can handled. This code checks to see if
* it can allocate all necessary resources then calls the
* nand layer to look for devices
*/
static int s3c2410_nand_probe(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct s3c2410_platform_nand *plat = to_nand_plat(dev);
struct s3c2410_nand_info *info;
struct s3c2410_nand_mtd *nmtd;
struct s3c2410_nand_set *sets;
struct resource *res;
int err = 0;
int size;
int nr_sets;
int setno;
pr_debug("s3c2410_nand_probe(%p)\n", dev);
info = kmalloc(sizeof(*info), GFP_KERNEL);
if (info == NULL) {
printk(KERN_ERR PFX "no memory for flash info\n");
err = -ENOMEM;
goto exit_error;
}
memzero(info, sizeof(*info));
dev_set_drvdata(dev, info);
spin_lock_init(&info->controller.lock);
/* get the clock source and enable it */
info->clk = clk_get(dev, "nand");
if (IS_ERR(info->clk)) {
printk(KERN_ERR PFX "failed to get clock");
err = -ENOENT;
goto exit_error;
}
clk_use(info->clk);
clk_enable(info->clk);
/* allocate and map the resource */
res = pdev->resource; /* assume that the flash has one resource */
size = res->end - res->start + 1;
info->area = request_mem_region(res->start, size, pdev->name);
if (info->area == NULL) {
printk(KERN_ERR PFX "cannot reserve register region\n");
err = -ENOENT;
goto exit_error;
}
info->device = dev;
info->platform = plat;
info->regs = ioremap(res->start, size);
if (info->regs == NULL) {
printk(KERN_ERR PFX "cannot reserve register region\n");
err = -EIO;
goto exit_error;
}
printk(KERN_INFO PFX "mapped registers at %p\n", info->regs);
/* initialise the hardware */
err = s3c2410_nand_inithw(info, dev);
if (err != 0)
goto exit_error;
sets = (plat != NULL) ? plat->sets : NULL;
nr_sets = (plat != NULL) ? plat->nr_sets : 1;
info->mtd_count = nr_sets;
/* allocate our information */
size = nr_sets * sizeof(*info->mtds);
info->mtds = kmalloc(size, GFP_KERNEL);
if (info->mtds == NULL) {
printk(KERN_ERR PFX "failed to allocate mtd storage\n");
err = -ENOMEM;
goto exit_error;
}
memzero(info->mtds, size);
/* initialise all possible chips */
nmtd = info->mtds;
for (setno = 0; setno < nr_sets; setno++, nmtd++) {
pr_debug("initialising set %d (%p, info %p)\n",
setno, nmtd, info);
s3c2410_nand_init_chip(info, nmtd, sets);
nmtd->scan_res = nand_scan(&nmtd->mtd,
(sets) ? sets->nr_chips : 1);
if (nmtd->scan_res == 0) {
s3c2410_nand_add_partition(info, nmtd, sets);
}
if (sets != NULL)
sets++;
}
pr_debug("initialised ok\n");
return 0;
exit_error:
s3c2410_nand_remove(dev);
if (err == 0)
err = -EINVAL;
return err;
}
static struct device_driver s3c2410_nand_driver = {
.name = "s3c2410-nand",
.bus = &platform_bus_type,
.probe = s3c2410_nand_probe,
.remove = s3c2410_nand_remove,
};
static int __init s3c2410_nand_init(void)
{
printk("S3C2410 NAND Driver, (c) 2004 Simtec Electronics\n");
return driver_register(&s3c2410_nand_driver);
}
static void __exit s3c2410_nand_exit(void)
{
driver_unregister(&s3c2410_nand_driver);
}
module_init(s3c2410_nand_init);
module_exit(s3c2410_nand_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
MODULE_DESCRIPTION("S3C2410 MTD NAND driver");
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