diff options
Diffstat (limited to 'drivers/mtd/nand/s3c2410.c')
-rw-r--r-- | drivers/mtd/nand/s3c2410.c | 704 |
1 files changed, 704 insertions, 0 deletions
diff --git a/drivers/mtd/nand/s3c2410.c b/drivers/mtd/nand/s3c2410.c new file mode 100644 index 0000000..d05e9b9 --- /dev/null +++ b/drivers/mtd/nand/s3c2410.c @@ -0,0 +1,704 @@ +/* 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"); |