From 9d75414b4fa7390975ef0e2b56ff40425657fe52 Mon Sep 17 00:00:00 2001 From: David Woodhouse Date: Sat, 13 May 2006 04:12:40 +0100 Subject: [PATCH] [MTD NAND] Update CS553x NAND driver: Hardware ECC support, optimisations. - Implement HW ECC support, - Provide read_buf() and write_buf() routines using memcpy - Use on-flash bad block table - Fix module refcounting - Avoid read/modify/write in hwcontrol() - Minor cosmetic fixes Partly based on code and ideas from Tom Sylla Signed-off-by: David Woodhouse --- drivers/mtd/nand/cs553x_nand.c | 102 ++++++++++++++++++++++++++++++----------- 1 file changed, 75 insertions(+), 27 deletions(-) diff --git a/drivers/mtd/nand/cs553x_nand.c b/drivers/mtd/nand/cs553x_nand.c index 91207a4..4f0b338 100644 --- a/drivers/mtd/nand/cs553x_nand.c +++ b/drivers/mtd/nand/cs553x_nand.c @@ -4,6 +4,7 @@ * (C) 2005, 2006 Red Hat Inc. * * Author: David Woodhouse + * Tom Sylla * * 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 @@ -22,6 +23,7 @@ #include #include #include +#include #include #include @@ -87,11 +89,34 @@ #define CS_NAND_ECC_CLRECC (1<<1) #define CS_NAND_ECC_ENECC (1<<0) +static void cs553x_read_buf(struct mtd_info *mtd, u_char *buf, int len) +{ + struct nand_chip *this = mtd->priv; + + while (unlikely(len > 0x800)) { + memcpy_fromio(buf, this->IO_ADDR_R, 0x800); + buf += 0x800; + len -= 0x800; + } + memcpy_fromio(buf, this->IO_ADDR_R, len); +} + +static void cs553x_write_buf(struct mtd_info *mtd, const u_char *buf, int len) +{ + struct nand_chip *this = mtd->priv; + + while (unlikely(len > 0x800)) { + memcpy_toio(this->IO_ADDR_R, buf, 0x800); + buf += 0x800; + len -= 0x800; + } + memcpy_toio(this->IO_ADDR_R, buf, len); +} + static unsigned char cs553x_read_byte(struct mtd_info *mtd) { struct nand_chip *this = mtd->priv; - unsigned char foo = readb(this->IO_ADDR_R); - return foo; + return readb(this->IO_ADDR_R); } static void cs553x_write_byte(struct mtd_info *mtd, u_char byte) @@ -110,35 +135,29 @@ static void cs553x_hwcontrol(struct mtd_info *mtd, int cmd) { struct nand_chip *this = mtd->priv; void __iomem *mmio_base = this->IO_ADDR_R; - - uint8_t old = readb(mmio_base + MM_NAND_CTL); + unsigned char ctl; switch(cmd) { case NAND_CTL_SETCLE: - old |= CS_NAND_CTL_CLE; + ctl = CS_NAND_CTL_CLE; break; case NAND_CTL_CLRCLE: - old &= ~CS_NAND_CTL_CLE; - break; - - case NAND_CTL_SETALE: - old |= CS_NAND_CTL_ALE; - break; - case NAND_CTL_CLRALE: - old &= ~CS_NAND_CTL_ALE; + case NAND_CTL_SETNCE: + ctl = 0; break; - case NAND_CTL_SETNCE: - old &= ~CS_NAND_CTL_CE; + case NAND_CTL_SETALE: + ctl = CS_NAND_CTL_ALE; break; + default: case NAND_CTL_CLRNCE: - old |= CS_NAND_CTL_CE; + ctl = CS_NAND_CTL_CE; break; } - writeb(old, mmio_base + MM_NAND_CTL); + writeb(ctl, mmio_base + MM_NAND_CTL); } @@ -151,6 +170,29 @@ static int cs553x_device_ready(struct mtd_info *mtd) return (foo & CS_NAND_STS_FLASH_RDY) && !(foo & CS_NAND_CTLR_BUSY); } + +static void cs_enable_hwecc(struct mtd_info *mtd, int mode) +{ + struct nand_chip *this = mtd->priv; + void __iomem *mmio_base = this->IO_ADDR_R; + + writeb(0x07, mmio_base + MM_NAND_ECC_CTL); +} + +static int cs_calculate_ecc(struct mtd_info *mtd, const u_char *dat, u_char *ecc_code) +{ + uint32_t ecc; + struct nand_chip *this = mtd->priv; + void __iomem *mmio_base = this->IO_ADDR_R; + + ecc = readl(mmio_base + MM_NAND_STS); + + ecc_code[1] = ecc >> 8; + ecc_code[0] = ecc >> 16; + ecc_code[2] = ecc >> 24; + return 0; +} + static struct mtd_info *cs553x_mtd[4]; static int __init cs553x_init_one(int cs, int mmio, unsigned long adr) @@ -167,7 +209,7 @@ static int __init cs553x_init_one(int cs, int mmio, unsigned long adr) } /* Allocate memory for MTD device structure and private data */ - new_mtd = kmalloc (sizeof(struct mtd_info) + sizeof (struct nand_chip), GFP_KERNEL); + new_mtd = kmalloc(sizeof(struct mtd_info) + sizeof (struct nand_chip), GFP_KERNEL); if (!new_mtd) { printk(KERN_WARNING "Unable to allocate CS553X NAND MTD device structure.\n"); err = -ENOMEM; @@ -178,8 +220,8 @@ static int __init cs553x_init_one(int cs, int mmio, unsigned long adr) this = (struct nand_chip *) (&new_mtd[1]); /* Initialize structures */ - memset((char *) new_mtd, 0, sizeof(struct mtd_info)); - memset((char *) this, 0, sizeof(struct nand_chip)); + memset(new_mtd, 0, sizeof(struct mtd_info)); + memset(this, 0, sizeof(struct nand_chip)); /* Link the private data with the MTD structure */ new_mtd->priv = this; @@ -196,27 +238,33 @@ static int __init cs553x_init_one(int cs, int mmio, unsigned long adr) this->dev_ready = cs553x_device_ready; this->read_byte = cs553x_read_byte; this->write_byte = cs553x_write_byte; + this->read_buf = cs553x_read_buf; + this->write_buf = cs553x_write_buf; - /* 20 us command delay time */ - this->chip_delay = 20; - this->eccmode = NAND_ECC_SOFT; + this->chip_delay = 0; + this->eccmode = NAND_ECC_HW3_256; + this->enable_hwecc = cs_enable_hwecc; + this->calculate_ecc = cs_calculate_ecc; + this->correct_data = nand_correct_data; + /* Enable the following for a flash based bad block table */ - // this->options = NAND_USE_FLASH_BBT; + this->options = NAND_USE_FLASH_BBT | NAND_NO_AUTOINCR; /* Scan to find existance of the device */ - if (nand_scan (new_mtd, 1)) { + if (nand_scan(new_mtd, 1)) { err = -ENXIO; goto out_ior; } + new_mtd->owner = THIS_MODULE; cs553x_mtd[cs] = new_mtd; goto out; out_ior: iounmap((void *)this->IO_ADDR_R); out_mtd: - kfree (new_mtd); + kfree(new_mtd); out: return err; } @@ -283,7 +331,7 @@ static void __exit cs553x_cleanup (void) iounmap(mmio_base); /* Free the MTD device structure */ - kfree (mtd); + kfree(mtd); } } module_exit(cs553x_cleanup); -- 2.7.4