[PATCH 2/2] MTD: atmel_nand: Update driver code to support Programmable HW ECC controller
Hong Xu
hong.xu at atmel.com
Thu Dec 8 01:53:39 EST 2011
The Programmable Hardware ECC (PMECC) controller is a programmable binary
BCH(Bose, Chaudhuri and Hocquenghem) encoder and decoder. This controller
can be used to support both SLC and MLC NAND Flash devices. It supports to
generate ECC to correct 2, 4, 8, 12 or 24 bits of error per sector of data.
To use this driver, the user needs to pass in the correction capability and
the sector size.
This driver has been tested on AT91SAM9X5-EK and AT91SAM9N12-EK with JFFS2,
YAFFS2 ,UBIFS and mtd-utils.
Signed-off-by: Hong Xu <hong.xu at atmel.com>
---
drivers/mtd/nand/atmel_nand.c | 235 ++++++++---
drivers/mtd/nand/atmel_nand_ecc.h | 78 ++++
drivers/mtd/nand/atmel_nand_pmecc.c | 745 +++++++++++++++++++++++++++++++++++
3 files changed, 993 insertions(+), 65 deletions(-)
create mode 100644 drivers/mtd/nand/atmel_nand_pmecc.c
diff --git a/drivers/mtd/nand/atmel_nand.c b/drivers/mtd/nand/atmel_nand.c
index 23e5d77..53d3682 100644
--- a/drivers/mtd/nand/atmel_nand.c
+++ b/drivers/mtd/nand/atmel_nand.c
@@ -15,6 +15,8 @@
* (u-boot-1.1.5/board/atmel/at91sam9263ek/nand.c)
* (C) Copyright 2006 ATMEL Rousset, Lacressonniere Nicolas
*
+ * Add Programmable Hardware ECC support for various AT91 SoC
+ * (C) Copyright 2011 ATMEL, Hong Xu
*
* 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
@@ -38,7 +40,9 @@
#include <mach/board.h>
#include <mach/cpu.h>
-#ifdef CONFIG_MTD_NAND_ATMEL_ECC_HW
+#if defined(CONFIG_MTD_NAND_ATMEL_ECC_HW)
+#define hard_ecc 1
+#elif defined(CONFIG_MTD_NAND_ATMEL_PMECC_HW)
#define hard_ecc 1
#else
#define hard_ecc 0
@@ -53,6 +57,8 @@
static int use_dma = 1;
module_param(use_dma, int, 0);
+#define NB_ERROR_MAX 25
+
static int on_flash_bbt = 0;
module_param(on_flash_bbt, int, 0);
@@ -62,8 +68,38 @@ module_param(on_flash_bbt, int, 0);
#define ecc_writel(add, reg, value) \
__raw_writel((value), add + ATMEL_ECC_##reg)
-#include "atmel_nand_ecc.h" /* Hardware ECC registers */
+/* Register access macros for PMECC */
+#define pmecc_readl(addr, reg) \
+ __raw_readl((addr) + ATMEL_PMECC_##reg)
+
+#define pmecc_writel(addr, reg, value) \
+ __raw_writel((value), (addr) + ATMEL_PMECC_##reg)
+
+#define pmecc_readb_ecc(addr, sector, n) \
+ __raw_readb((addr) + ATMEL_PMECC_ECCx + ((sector) * 0x40) + (n))
+
+#define pmecc_readl_rem(addr, sector, n) \
+ __raw_readl((addr) + ATMEL_PMECC_REMx + ((sector) * 0x40) + ((n) * 4))
+
+#define pmerrloc_readl(addr, reg) \
+ __raw_readl((addr) + ATMEL_PMERRLOC_##reg)
+
+#define pmerrloc_writel(addr, reg, value) \
+ __raw_writel((value), (addr) + ATMEL_PMERRLOC_##reg)
+
+#define pmerrloc_writel_sigma(addr, n, value) \
+ __raw_writel((value), (addr) + ATMEL_PMERRLOC_SIGMAx + ((n) * 4))
+
+#define pmerrloc_readl_sigma(addr, n) \
+ __raw_readl((addr) + ATMEL_PMERRLOC_SIGMAx + ((n) * 4))
+
+#define pmerrloc_readl_el(addr, n) \
+ __raw_readl((addr) + ATMEL_PMERRLOC_ELx + ((n) * 4))
+/* Include Hardware ECC registers */
+#include "atmel_nand_ecc.h"
+
+#if defined(CONFIG_MTD_NAND_ATMEL_ECC_HW)
/* oob layout for large page size
* bad block info is on bytes 0 and 1
* the bytes have to be consecutives to avoid
@@ -89,6 +125,7 @@ static struct nand_ecclayout atmel_oobinfo_small = {
{6, 10}
},
};
+#endif
struct atmel_nand_host {
struct nand_chip nand_chip;
@@ -101,11 +138,42 @@ struct atmel_nand_host {
struct completion comp;
struct dma_chan *dma_chan;
+
+#if defined(CONFIG_MTD_NAND_ATMEL_PMECC_HW)
+ void __iomem *pmerrloc_base;
+ void __iomem *rom_base;
+ /* defines the error correcting capability */
+ int tt;
+ /* The number of ecc bytes for one sector */
+ int ecc_bytes_per_sector;
+ /* degree of the remainders, GF(2**mm) */
+ int mm;
+ /* length of codeword, nn=2**mm -1 */
+ int nn;
+ int sector_number;
+
+ /* lookup table for alpha_to and index_of */
+ int16_t *alpha_to;
+ int16_t *index_of;
+
+ int16_t partial_syn[100];
+ int16_t si[100];
+ /* Sigma table */
+ int16_t smu[NB_ERROR_MAX + 2][2 * NB_ERROR_MAX + 1];
+ /* polynomal order */
+ int16_t lmu[NB_ERROR_MAX + 1];
+ uint8_t ecc_table[42 * 8];
+#endif
};
+#if defined(CONFIG_MTD_NAND_ATMEL_PMECC_HW)
+#include "atmel_nand_pmecc.c"
+#endif
+
static int cpu_has_dma(void)
{
- return cpu_is_at91sam9rl() || cpu_is_at91sam9g45();
+ return cpu_is_at91sam9rl() || cpu_is_at91sam9g45()
+ || cpu_is_at91sam9x5() || cpu_is_at91sam9n12();
}
/*
@@ -228,7 +296,7 @@ err_dma:
dma_unmap_single(dma_dev->dev, phys_addr, len, dir);
err_buf:
if (err != 0)
- dev_warn(host->dev, "Fall back to CPU I/O\n");
+ dev_dbg(host->dev, "Fall back to CPU I/O\n");
return err;
}
@@ -258,6 +326,7 @@ static void atmel_write_buf(struct mtd_info *mtd, const u8 *buf, int len)
memcpy_toio(chip->IO_ADDR_W, buf, len);
}
+#if defined(CONFIG_MTD_NAND_ATMEL_ECC_HW)
/*
* Calculate HW ECC
*
@@ -444,6 +513,84 @@ static void atmel_nand_hwctl(struct mtd_info *mtd, int mode)
}
}
+static int __init atmel_nand_init_params(struct platform_device *pdev,
+ struct atmel_nand_host *host)
+{
+ struct resource *regs;
+ struct nand_chip *nand_chip;
+ struct mtd_info *mtd;
+
+ nand_chip = &host->nand_chip;
+ mtd = &host->mtd;
+
+ regs = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ if (!regs && hard_ecc) {
+ dev_err(host->dev, "atmel_nand: can't get I/O resource "
+ "regs\nFalling back on software ECC\n");
+ }
+
+ nand_chip->ecc.mode = NAND_ECC_SOFT; /* enable ECC */
+ if (no_ecc)
+ nand_chip->ecc.mode = NAND_ECC_NONE;
+ if (hard_ecc && regs) {
+ host->ecc = ioremap(regs->start, resource_size(regs));
+ if (host->ecc == NULL) {
+ printk(KERN_ERR "atmel_nand: ioremap failed\n");
+ goto err_ecc_ioremap;
+ }
+
+ nand_chip->ecc.mode = NAND_ECC_HW;
+ nand_chip->ecc.calculate = atmel_nand_calculate;
+ nand_chip->ecc.correct = atmel_nand_correct;
+ nand_chip->ecc.hwctl = atmel_nand_hwctl;
+ nand_chip->ecc.read_page = atmel_nand_read_page;
+ nand_chip->ecc.bytes = 4;
+ }
+
+ if (nand_chip->ecc.mode == NAND_ECC_HW) {
+ /* ECC is calculated for the whole page (1 step) */
+ nand_chip->ecc.size = mtd->writesize;
+
+ /* set ECC page size and oob layout */
+ switch (mtd->writesize) {
+ case 512:
+ nand_chip->ecc.layout = &atmel_oobinfo_small;
+ ecc_writel(host->ecc, MR, ATMEL_ECC_PAGESIZE_528);
+ break;
+ case 1024:
+ nand_chip->ecc.layout = &atmel_oobinfo_large;
+ ecc_writel(host->ecc, MR, ATMEL_ECC_PAGESIZE_1056);
+ break;
+ case 2048:
+ nand_chip->ecc.layout = &atmel_oobinfo_large;
+ ecc_writel(host->ecc, MR, ATMEL_ECC_PAGESIZE_2112);
+ break;
+ case 4096:
+ nand_chip->ecc.layout = &atmel_oobinfo_large;
+ ecc_writel(host->ecc, MR, ATMEL_ECC_PAGESIZE_4224);
+ break;
+ default:
+ /* page size not handled by HW ECC */
+ /* switching back to soft ECC */
+ nand_chip->ecc.mode = NAND_ECC_SOFT;
+ nand_chip->ecc.calculate = NULL;
+ nand_chip->ecc.correct = NULL;
+ nand_chip->ecc.hwctl = NULL;
+ nand_chip->ecc.read_page = NULL;
+ nand_chip->ecc.postpad = 0;
+ nand_chip->ecc.prepad = 0;
+ nand_chip->ecc.bytes = 0;
+ break;
+ }
+ }
+
+ return 0;
+
+err_ecc_ioremap:
+ return -EIO;
+}
+#endif
+
/*
* Probe for the NAND device.
*/
@@ -452,9 +599,8 @@ static int __init atmel_nand_probe(struct platform_device *pdev)
struct atmel_nand_host *host;
struct mtd_info *mtd;
struct nand_chip *nand_chip;
- struct resource *regs;
struct resource *mem;
- int res;
+ int res = 0;
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!mem) {
@@ -495,29 +641,9 @@ static int __init atmel_nand_probe(struct platform_device *pdev)
if (host->board->rdy_pin)
nand_chip->dev_ready = atmel_nand_device_ready;
- regs = platform_get_resource(pdev, IORESOURCE_MEM, 1);
- if (!regs && hard_ecc) {
- printk(KERN_ERR "atmel_nand: can't get I/O resource "
- "regs\nFalling back on software ECC\n");
- }
-
nand_chip->ecc.mode = NAND_ECC_SOFT; /* enable ECC */
if (no_ecc)
nand_chip->ecc.mode = NAND_ECC_NONE;
- if (hard_ecc && regs) {
- host->ecc = ioremap(regs->start, resource_size(regs));
- if (host->ecc == NULL) {
- printk(KERN_ERR "atmel_nand: ioremap failed\n");
- res = -EIO;
- goto err_ecc_ioremap;
- }
- nand_chip->ecc.mode = NAND_ECC_HW;
- nand_chip->ecc.calculate = atmel_nand_calculate;
- nand_chip->ecc.correct = atmel_nand_correct;
- nand_chip->ecc.hwctl = atmel_nand_hwctl;
- nand_chip->ecc.read_page = atmel_nand_read_page;
- nand_chip->ecc.bytes = 4;
- }
nand_chip->chip_delay = 20; /* 20us command delay time */
@@ -569,42 +695,13 @@ static int __init atmel_nand_probe(struct platform_device *pdev)
goto err_scan_ident;
}
- if (nand_chip->ecc.mode == NAND_ECC_HW) {
- /* ECC is calculated for the whole page (1 step) */
- nand_chip->ecc.size = mtd->writesize;
-
- /* set ECC page size and oob layout */
- switch (mtd->writesize) {
- case 512:
- nand_chip->ecc.layout = &atmel_oobinfo_small;
- ecc_writel(host->ecc, MR, ATMEL_ECC_PAGESIZE_528);
- break;
- case 1024:
- nand_chip->ecc.layout = &atmel_oobinfo_large;
- ecc_writel(host->ecc, MR, ATMEL_ECC_PAGESIZE_1056);
- break;
- case 2048:
- nand_chip->ecc.layout = &atmel_oobinfo_large;
- ecc_writel(host->ecc, MR, ATMEL_ECC_PAGESIZE_2112);
- break;
- case 4096:
- nand_chip->ecc.layout = &atmel_oobinfo_large;
- ecc_writel(host->ecc, MR, ATMEL_ECC_PAGESIZE_4224);
- break;
- default:
- /* page size not handled by HW ECC */
- /* switching back to soft ECC */
- nand_chip->ecc.mode = NAND_ECC_SOFT;
- nand_chip->ecc.calculate = NULL;
- nand_chip->ecc.correct = NULL;
- nand_chip->ecc.hwctl = NULL;
- nand_chip->ecc.read_page = NULL;
- nand_chip->ecc.postpad = 0;
- nand_chip->ecc.prepad = 0;
- nand_chip->ecc.bytes = 0;
- break;
- }
- }
+#if defined(CONFIG_MTD_NAND_ATMEL_ECC_HW)
+ res = atmel_nand_init_params(pdev, host);
+#elif defined(CONFIG_MTD_NAND_ATMEL_PMECC_HW)
+ res = atmel_pmecc_init_params(pdev, host);
+#endif
+ if (res != 0)
+ goto err;
/* second phase scan */
if (nand_scan_tail(mtd)) {
@@ -618,6 +715,7 @@ static int __init atmel_nand_probe(struct platform_device *pdev)
if (!res)
return res;
+err:
err_scan_tail:
err_scan_ident:
err_no_card:
@@ -625,9 +723,6 @@ err_no_card:
platform_set_drvdata(pdev, NULL);
if (host->dma_chan)
dma_release_channel(host->dma_chan);
- if (host->ecc)
- iounmap(host->ecc);
-err_ecc_ioremap:
iounmap(host->io_base);
err_nand_ioremap:
kfree(host);
@@ -646,6 +741,16 @@ static int __exit atmel_nand_remove(struct platform_device *pdev)
atmel_nand_disable(host);
+#if defined(CONFIG_MTD_NAND_ATMEL_PMECC_HW)
+ if (cpu_has_pmecc())
+ pmecc_writel(host->ecc, CTRL, PMECC_CTRL_DISABLE);
+ if (host->pmerrloc_base) {
+ pmerrloc_writel(host->pmerrloc_base, ELDIS, PMERRLOC_DISABLE);
+ iounmap(host->pmerrloc_base);
+ }
+ if (host->rom_base)
+ iounmap(host->rom_base);
+#endif
if (host->ecc)
iounmap(host->ecc);
diff --git a/drivers/mtd/nand/atmel_nand_ecc.h b/drivers/mtd/nand/atmel_nand_ecc.h
index 578c776..f7ae3e3 100644
--- a/drivers/mtd/nand/atmel_nand_ecc.h
+++ b/drivers/mtd/nand/atmel_nand_ecc.h
@@ -36,4 +36,82 @@
#define ATMEL_ECC_NPR 0x10 /* NParity register */
#define ATMEL_ECC_NPARITY (0xffff << 0) /* NParity */
+/* PMECC Register Definitions */
+#define ATMEL_PMECC_CFG 0x000 /* Configuration Register */
+#define PMECC_CFG_BCH_ERR2 (0 << 0)
+#define PMECC_CFG_BCH_ERR4 (1 << 0)
+#define PMECC_CFG_BCH_ERR8 (2 << 0)
+#define PMECC_CFG_BCH_ERR12 (3 << 0)
+#define PMECC_CFG_BCH_ERR24 (4 << 0)
+
+#define PMECC_CFG_SECTOR512 (0 << 4)
+#define PMECC_CFG_SECTOR1024 (1 << 4)
+
+#define PMECC_CFG_PAGE_1SECTOR (0 << 8)
+#define PMECC_CFG_PAGE_2SECTORS (1 << 8)
+#define PMECC_CFG_PAGE_4SECTORS (2 << 8)
+#define PMECC_CFG_PAGE_8SECTORS (3 << 8)
+
+#define PMECC_CFG_READ_OP (0 << 12)
+#define PMECC_CFG_WRITE_OP (1 << 12)
+
+#define PMECC_CFG_SPARE_ENABLE (1 << 16)
+#define PMECC_CFG_SPARE_DISABLE (0 << 16)
+
+#define PMECC_CFG_AUTO_ENABLE (1 << 20)
+#define PMECC_CFG_AUTO_DISABLE (0 << 20)
+
+#define ATMEL_PMECC_SAREA 0x004 /* Spare area size */
+#define ATMEL_PMECC_SADDR 0x008 /* PMECC starting address */
+#define ATMEL_PMECC_EADDR 0x00c /* PMECC ending address */
+#define ATMEL_PMECC_CLK 0x010 /* PMECC clock control */
+#define PMECC_CLK_133MHZ (2 << 0)
+
+#define ATMEL_PMECC_CTRL 0x014 /* PMECC control register */
+#define PMECC_CTRL_RST (1 << 0)
+#define PMECC_CTRL_DATA (1 << 1)
+#define PMECC_CTRL_USER (1 << 2)
+#define PMECC_CTRL_ENABLE (1 << 4)
+#define PMECC_CTRL_DISABLE (1 << 5)
+
+#define ATMEL_PMECC_SR 0x018 /* PMECC status register */
+#define PMECC_SR_BUSY (1 << 0)
+#define PMECC_SR_ENABLE (1 << 4)
+
+#define ATMEL_PMECC_IER 0x01c /* PMECC interrupt enable */
+#define PMECC_IER_ENABLE (1 << 0)
+#define ATMEL_PMECC_IDR 0x020 /* PMECC interrupt disable */
+#define PMECC_IER_DISABLE (1 << 0)
+#define ATMEL_PMECC_IMR 0x024 /* PMECC interrupt mask */
+#define PMECC_IER_MASK (1 << 0)
+#define ATMEL_PMECC_ISR 0x028 /* PMECC interrupt status */
+#define ATMEL_PMECC_ECCx 0x040 /* PMECC ECC x */
+#define ATMEL_PMECC_REMx 0x240 /* PMECC REM x */
+
+/* PMERRLOC Register Definitions */
+#define ATMEL_PMERRLOC_ELCFG 0x000 /* Error location config */
+#define PMERRLOC_ELCFG_SECTOR_512 (0 << 0)
+#define PMERRLOC_ELCFG_SECTOR_1024 (1 << 0)
+#define PMERRLOC_ELCFG_NUM_ERRORS(n) ((n) << 16)
+
+#define ATMEL_PMERRLOC_ELPRIM 0x004 /* Error location primitive */
+#define ATMEL_PMERRLOC_ELEN 0x008 /* Error location enable */
+#define ATMEL_PMERRLOC_ELDIS 0x00c /* Error location disable */
+#define PMERRLOC_DISABLE (1 << 0)
+
+#define ATMEL_PMERRLOC_ELSR 0x010 /* Error location status */
+#define PMERRLOC_ELSR_BUSY (1 << 0)
+#define ATMEL_PMERRLOC_ELIER 0x014 /* Error location int enable */
+#define ATMEL_PMERRLOC_ELIDR 0x018 /* Error location int disable */
+#define ATMEL_PMERRLOC_ELIMR 0x01c /* Error location int mask */
+#define ATMEL_PMERRLOC_ELISR 0x020 /* Error location int status */
+#define PMERRLOC_ERR_NUM_MASK (0x1f << 8)
+#define PMERRLOC_CALC_DONE (1 << 0)
+#define ATMEL_PMERRLOC_SIGMAx 0x028 /* Error location SIGMA x */
+#define ATMEL_PMERRLOC_ELx 0x08c /* Error location x */
+
+/* Galois field dimension */
+#define GF_DIMENSION_13 13
+#define GF_DIMENSION_14 14
+
#endif
diff --git a/drivers/mtd/nand/atmel_nand_pmecc.c b/drivers/mtd/nand/atmel_nand_pmecc.c
new file mode 100644
index 0000000..d1084ac
--- /dev/null
+++ b/drivers/mtd/nand/atmel_nand_pmecc.c
@@ -0,0 +1,745 @@
+/*
+ * (C) Copyright 2011 ATMEL, Hong Xu
+ *
+ * PMECC related definitions and routines
+ *
+ * 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.
+ *
+ */
+
+static struct nand_ecclayout atmel_pmecc_oobinfo;
+/*
+ * Number of ECC bytes per sector is determined by both sector size
+ * and correction capability
+ *
+ * Correction Capability Sector_512_bytes Sector_1024_bytes
+ * ===================== ================ =================
+ * 2-bits 4-bytes 4-bytes
+ * 4-bits 7-bytes 7-bytes
+ * 8-bits 13-bytes 14-bytes
+ * 12-bits 20-bytes 21-bytes
+ * 24-bits 39-bytes 42-bytes
+ *
+ */
+static const int ecc_bytes_table[5][2] = {
+ {4, 4}, {7, 7}, {13, 14}, {20, 21}, {39, 42}
+};
+
+/*
+ * Return number of ecc bytes per sector according to sector size and
+ * correction capability
+ */
+static int pmecc_get_ecc_bytes(int cap, int sector_size)
+{
+ int i, j;
+
+ switch (cap) {
+ case 2:
+ i = 0;
+ break;
+ case 4:
+ i = 1;
+ break;
+ case 8:
+ i = 2;
+ break;
+ case 12:
+ i = 3;
+ break;
+ case 24:
+ i = 4;
+ break;
+ default:
+ BUG();
+ }
+
+ switch (sector_size) {
+ case 512:
+ j = 0;
+ break;
+ case 1024:
+ j = 1;
+ break;
+ default:
+ BUG();
+ }
+
+ return ecc_bytes_table[i][j];
+}
+
+static int cpu_has_pmecc(void)
+{
+ return cpu_is_at91sam9x5() || cpu_is_at91sam9n12();
+}
+
+static void pmecc_config_ecc_layout(struct nand_ecclayout *layout, int oobsize,
+ int ecc_len)
+{
+ int i;
+
+ layout->eccbytes = ecc_len;
+
+ /* ECC will occupy the last ecc_len bytes continuously */
+ for (i = 0; i < ecc_len; i++)
+ layout->eccpos[i] = oobsize - ecc_len + i;
+
+ /* Reserve at least first 2 bytes */
+ layout->oobfree[0].offset = 2;
+ layout->oobfree[0].length = oobsize - ecc_len - 2;
+}
+
+static int16_t *pmecc_get_alpha_to(struct atmel_nand_host *host)
+{
+ int16_t *p;
+
+ if (host->board->sector_size == 512)
+ p = (int16_t *)((u32)host->rom_base +
+ AT_PMECC_LOOKUP_TABLE_OFFSET_512) +
+ AT_PMECC_LOOKUP_TABLE_SIZE_512;
+ else
+ p = (int16_t *)((u32)host->rom_base +
+ AT_PMECC_LOOKUP_TABLE_OFFSET_1024) +
+ AT_PMECC_LOOKUP_TABLE_SIZE_1024;
+ return p;
+}
+
+static int16_t *pmecc_get_index_of(struct atmel_nand_host *host)
+{
+ int16_t *p = (int16_t *)host->rom_base;
+
+ if (host->board->sector_size == 512)
+ p = (int16_t *)((u32)host->rom_base +
+ AT_PMECC_LOOKUP_TABLE_OFFSET_512);
+ else
+ p = (int16_t *)((u32)host->rom_base +
+ AT_PMECC_LOOKUP_TABLE_OFFSET_1024);
+ return p;
+}
+
+static void pmecc_gen_syndrome(struct mtd_info *mtd, int sector)
+{
+ int i;
+ uint32_t value;
+ struct nand_chip *nand_chip = mtd->priv;
+ struct atmel_nand_host *host = nand_chip->priv;
+
+ /* Fill odd syndromes */
+ for (i = 0; i < host->tt; i++) {
+ value = pmecc_readl_rem(host->ecc, sector, i / 2);
+ if (i % 2 == 0)
+ value &= 0xffff;
+ else
+ value = (value & 0xffff0000) >> 16;
+ host->partial_syn[(2 * i) + 1] = value;
+ }
+}
+
+static void pmecc_substitute(struct mtd_info *mtd)
+{
+ int16_t *si;
+ int i, j;
+ struct nand_chip *nand_chip = mtd->priv;
+ struct atmel_nand_host *host = nand_chip->priv;
+ int16_t *alpha_to = host->alpha_to;
+ int16_t *index_of = host->index_of;
+ int16_t *partial_syn = host->partial_syn;
+
+ /* si[] is a table that holds the current syndrome value,
+ * an element of that table belongs to the field
+ */
+ si = host->si;
+
+ for (i = 1; i < 2 * NB_ERROR_MAX; i++)
+ si[i] = 0;
+
+ /* Computation 2t syndromes based on S(x) */
+ /* Odd syndromes */
+ for (i = 1; i <= 2 * host->tt - 1; i = i + 2) {
+ si[i] = 0;
+ for (j = 0; j < host->mm; j++) {
+ if (partial_syn[i] & ((unsigned short)0x1 << j))
+ si[i] = alpha_to[(i * j)] ^ si[i];
+ }
+ }
+ /* Even syndrome = (Odd syndrome) ** 2 */
+ for (i = 2; i <= 2 * host->tt; i = i + 2) {
+ j = i / 2;
+ if (si[j] == 0)
+ si[i] = 0;
+ else
+ si[i] = alpha_to[(2 * index_of[si[j]]) % host->nn];
+ }
+
+ return;
+}
+
+static void pmecc_get_sigma(struct mtd_info *mtd)
+{
+ int i, j, k;
+ struct nand_chip *nand_chip = mtd->priv;
+ struct atmel_nand_host *host = nand_chip->priv;
+
+ uint32_t dmu_0_count, tmp;
+ int16_t *lmu = host->lmu;
+ int16_t *si = host->si;
+ int16_t tt = host->tt;
+ int16_t *index_of = host->index_of;
+
+ /* mu */
+ int mu[NB_ERROR_MAX + 1];
+
+ /* discrepancy */
+ int dmu[NB_ERROR_MAX + 1];
+
+ /* delta order */
+ int delta[NB_ERROR_MAX + 1];
+
+ /* index of largest delta */
+ int ro;
+ int largest;
+ int diff;
+
+ dmu_0_count = 0;
+
+ /* First Row */
+
+ /* Mu */
+ mu[0] = -1;
+
+ for (i = 0; i < 2 * NB_ERROR_MAX + 1; i++)
+ host->smu[0][i] = 0;
+
+ host->smu[0][0] = 1;
+
+ /* discrepancy set to 1 */
+ dmu[0] = 1;
+ /* polynom order set to 0 */
+ lmu[0] = 0;
+ delta[0] = (mu[0] * 2 - lmu[0]) >> 1;
+
+ /* Second Row */
+
+ /* Mu */
+ mu[1] = 0;
+ /* Sigma(x) set to 1 */
+ for (i = 0; i < (2 * NB_ERROR_MAX + 1); i++)
+ host->smu[1][i] = 0;
+
+ host->smu[1][0] = 1;
+
+ /* discrepancy set to S1 */
+ dmu[1] = si[1];
+
+ /* polynom order set to 0 */
+ lmu[1] = 0;
+
+ delta[1] = (mu[1] * 2 - lmu[1]) >> 1;
+
+ /* Init the Sigma(x) last row */
+ for (i = 0; i < (2 * NB_ERROR_MAX + 1); i++)
+ host->smu[tt + 1][i] = 0;
+
+ for (i = 1; i <= tt; i++) {
+ mu[i+1] = i << 1;
+ /* Begin Computing Sigma (Mu+1) and L(mu) */
+ /* check if discrepancy is set to 0 */
+ if (dmu[i] == 0) {
+ dmu_0_count++;
+
+ tmp = ((tt - (lmu[i] >> 1) - 1) / 2);
+ if ((tt - (lmu[i] >> 1) - 1) & 0x1)
+ tmp += 2;
+ else
+ tmp += 1;
+
+ if (dmu_0_count == tmp) {
+ for (j = 0; j <= (lmu[i] >> 1) + 1; j++)
+ host->smu[tt + 1][j] = host->smu[i][j];
+
+ lmu[tt + 1] = lmu[i];
+ return;
+ }
+
+ /* copy polynom */
+ for (j = 0; j <= lmu[i] >> 1; j++)
+ host->smu[i + 1][j] = host->smu[i][j];
+
+ /* copy previous polynom order to the next */
+ lmu[i + 1] = lmu[i];
+ } else {
+ ro = 0;
+ largest = -1;
+ /* find largest delta with dmu != 0 */
+ for (j = 0; j < i; j++) {
+ if ((dmu[j]) && (delta[j] > largest)) {
+ largest = delta[j];
+ ro = j;
+ }
+ }
+
+ /* compute difference */
+ diff = (mu[i] - mu[ro]);
+
+ /* Compute degree of the new smu polynomial */
+ if ((lmu[i] >> 1) > ((lmu[ro] >> 1) + diff))
+ lmu[i + 1] = lmu[i];
+ else
+ lmu[i + 1] = ((lmu[ro] >> 1) + diff) * 2;
+
+ /* Init smu[i+1] with 0 */
+ for (k = 0; k < (2 * NB_ERROR_MAX + 1); k++)
+ host->smu[i+1][k] = 0;
+
+ /* Compute smu[i+1] */
+ for (k = 0; k <= lmu[ro] >> 1; k++) {
+ if (!(host->smu[ro][k] && dmu[i]))
+ continue;
+
+ tmp = host->index_of[dmu[i]] +
+ (host->nn - host->index_of[dmu[ro]]) +
+ host->index_of[host->smu[ro][k]];
+ host->smu[i + 1][k + diff] =
+ host->alpha_to[tmp % host->nn];
+ }
+
+ for (k = 0; k <= lmu[i] >> 1; k++)
+ host->smu[i + 1][k] ^= host->smu[i][k];
+ }
+
+ /* End Computing Sigma (Mu+1) and L(mu) */
+ /* In either case compute delta */
+ delta[i + 1] = (mu[i + 1] * 2 - lmu[i + 1]) >> 1;
+
+ /* Do not compute discrepancy for the last iteration */
+ if (i >= tt)
+ continue;
+
+ for (k = 0 ; k <= (lmu[i + 1] >> 1); k++) {
+ tmp = 2 * (i - 1);
+ if (k == 0)
+ dmu[i + 1] = si[tmp + 3];
+ else if (host->smu[i+1][k] && si[tmp + 3 - k]) {
+ tmp = index_of[host->smu[i + 1][k]] +
+ index_of[si[2 * (i - 1) + 3 - k]];
+ tmp %= host->nn;
+ dmu[i + 1] = host->alpha_to[tmp] ^ dmu[i + 1];
+ }
+ }
+ }
+
+ return;
+}
+
+static int pmecc_err_location(struct mtd_info *mtd)
+{
+ int i, gf_dimension;
+ int err_nbr; /* number of error */
+ int roots_nbr; /* number of roots */
+ int sector_size;
+ uint32_t val;
+ struct nand_chip *nand_chip = mtd->priv;
+ struct atmel_nand_host *host = nand_chip->priv;
+
+ sector_size = host->board->sector_size;
+ if (sector_size == 512)
+ gf_dimension = GF_DIMENSION_13;
+ else
+ gf_dimension = GF_DIMENSION_14;
+
+ /* Disable PMECC Error Location IP */
+ pmerrloc_writel(host->pmerrloc_base, ELDIS, PMERRLOC_DISABLE);
+ err_nbr = 0;
+
+ for (i = 0; i <= host->lmu[host->tt + 1] >> 1; i++) {
+ pmerrloc_writel_sigma(host->pmerrloc_base, i,
+ host->smu[host->tt + 1][i]);
+ err_nbr++;
+ }
+
+ val = ((err_nbr - 1) << 16) | ((sector_size == 512) ? 0 : 1);
+ pmerrloc_writel(host->pmerrloc_base, ELCFG, val);
+
+ pmerrloc_writel(host->pmerrloc_base, ELEN,
+ sector_size * 8 + gf_dimension * host->tt);
+
+ while (!(pmerrloc_readl(host->pmerrloc_base, ELISR)
+ & PMERRLOC_CALC_DONE))
+ cpu_relax();
+
+ roots_nbr = (pmerrloc_readl(host->pmerrloc_base, ELISR)
+ & PMERRLOC_ERR_NUM_MASK) >> 8;
+
+ /* Number of roots == degree of smu hence <= tt */
+ if (roots_nbr == host->lmu[host->tt + 1] >> 1)
+ return err_nbr - 1;
+
+ /* Number of roots does not match the degree of smu
+ * unable to correct error */
+ return -1;
+}
+
+static void pmecc_correct_data(struct mtd_info *mtd, uint8_t *buf,
+ int extra_bytes, int err_nbr)
+{
+ int i = 0;
+ int byte_pos, bit_pos;
+ int sector_size, ecc_size;
+ uint32_t tmp;
+ struct nand_chip *nand_chip = mtd->priv;
+ struct atmel_nand_host *host = nand_chip->priv;
+
+ sector_size = host->board->sector_size;
+ ecc_size = nand_chip->ecc.bytes;
+
+ while (err_nbr) {
+ byte_pos = (pmerrloc_readl_el(host->pmerrloc_base, i) - 1) / 8;
+ bit_pos = (pmerrloc_readl_el(host->pmerrloc_base, i) - 1) % 8;
+ dev_info(host->dev, "PMECC correction, byte_pos: %d "
+ "bit_pos: %d\n", byte_pos, bit_pos);
+
+ if (byte_pos < (sector_size + extra_bytes)) {
+ tmp = sector_size + pmecc_readl(host->ecc, SADDR);
+ if (byte_pos < tmp) {
+ if (*(buf + byte_pos) & (1 << bit_pos))
+ *(buf + byte_pos) &=
+ (0xFF ^ (1 << bit_pos));
+ else
+ *(buf + byte_pos) |= (1 << bit_pos);
+ } else {
+ if (*(buf + byte_pos + ecc_size) &
+ (1 << bit_pos))
+ *(buf + byte_pos + ecc_size) &=
+ (0xFF ^ (1 << bit_pos));
+ else
+ *(buf + byte_pos + ecc_size) |=
+ (1 << bit_pos);
+ }
+ }
+
+ i++;
+ err_nbr--;
+ }
+
+ return;
+}
+
+static int pmecc_correction(struct mtd_info *mtd, u32 pmecc_stat, uint8_t *buf,
+ u8 *ecc)
+{
+ int i, err_nbr;
+ uint8_t *buf_pos;
+ struct nand_chip *nand_chip = mtd->priv;
+ int eccbytes = nand_chip->ecc.bytes;
+ struct atmel_nand_host *host = nand_chip->priv;
+
+ for (i = 0; i < eccbytes; i++)
+ if (ecc[i] != 0xff)
+ goto normal_check;
+ /* Erased page, return OK */
+ return 0;
+
+normal_check:
+ for (i = 0; i < host->sector_number; i++) {
+ err_nbr = 0;
+ if (pmecc_stat & 0x1) {
+ buf_pos = buf + i * host->board->sector_size;
+
+ pmecc_gen_syndrome(mtd, i);
+ pmecc_substitute(mtd);
+ pmecc_get_sigma(mtd);
+
+ err_nbr = pmecc_err_location(mtd);
+ if (err_nbr == -1) {
+ dev_err(host->dev, "PMECC: Too many errors\n");
+ mtd->ecc_stats.failed++;
+ return -EFAULT;
+ } else {
+ pmecc_correct_data(mtd, buf_pos, 0, err_nbr);
+ mtd->ecc_stats.corrected += err_nbr;
+ }
+ }
+ pmecc_stat >>= 1;
+ }
+
+ return 0;
+}
+
+static int atmel_nand_pmecc_read_page(struct mtd_info *mtd,
+ struct nand_chip *chip, uint8_t *buf, int32_t page)
+{
+ struct atmel_nand_host *host = chip->priv;
+ int eccsize = chip->ecc.size;
+ uint32_t *eccpos = chip->ecc.layout->eccpos;
+ int err = 0, stat;
+ uint8_t *oob = chip->oob_poi;
+
+ pmecc_writel(host->ecc, CTRL, PMECC_CTRL_RST);
+ pmecc_writel(host->ecc, CTRL, PMECC_CTRL_DISABLE);
+ pmecc_writel(host->ecc, CFG, (pmecc_readl(host->ecc, CFG)
+ & ~PMECC_CFG_WRITE_OP) | PMECC_CFG_AUTO_ENABLE);
+
+ pmecc_writel(host->ecc, CTRL, PMECC_CTRL_ENABLE);
+ pmecc_writel(host->ecc, CTRL, PMECC_CTRL_DATA);
+
+ chip->read_buf(mtd, buf, eccsize);
+ chip->read_buf(mtd, oob, mtd->oobsize);
+
+ while ((pmecc_readl(host->ecc, SR) & PMECC_SR_BUSY))
+ cpu_relax();
+
+ stat = pmecc_readl(host->ecc, ISR);
+
+ if (stat != 0) {
+ if (pmecc_correction(mtd, stat, buf, &oob[eccpos[0]]))
+ err = -1;
+ }
+
+ return err;
+}
+
+static void atmel_nand_pmecc_write_page(struct mtd_info *mtd,
+ struct nand_chip *chip, const uint8_t *buf)
+{
+ int i, j;
+ struct atmel_nand_host *host = chip->priv;
+ uint32_t *eccpos = chip->ecc.layout->eccpos;
+
+ pmecc_writel(host->ecc, CTRL, PMECC_CTRL_RST);
+ pmecc_writel(host->ecc, CTRL, PMECC_CTRL_DISABLE);
+
+ pmecc_writel(host->ecc, CFG, (pmecc_readl(host->ecc, CFG) |
+ PMECC_CFG_WRITE_OP) & ~PMECC_CFG_AUTO_ENABLE);
+
+ pmecc_writel(host->ecc, CTRL, PMECC_CTRL_ENABLE);
+ pmecc_writel(host->ecc, CTRL, PMECC_CTRL_DATA);
+
+ chip->write_buf(mtd, (u8 *)buf, mtd->writesize);
+
+ while ((pmecc_readl(host->ecc, SR) & PMECC_SR_BUSY))
+ cpu_relax();
+
+ for (i = 0; i < host->sector_number; i++) {
+ for (j = 0; j < host->ecc_bytes_per_sector; j++) {
+ int pos;
+
+ pos = i * host->ecc_bytes_per_sector + j;
+ chip->oob_poi[eccpos[pos]] =
+ pmecc_readb_ecc(host->ecc, i, j);
+ }
+ }
+ chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
+
+ return;
+}
+
+static void atmel_pmecc_core_init(struct mtd_info *mtd)
+{
+ uint32_t val = 0;
+ struct nand_chip *nand_chip = mtd->priv;
+ struct atmel_nand_host *host = nand_chip->priv;
+ struct nand_ecclayout *ecc_layout;
+
+ pmecc_writel(host->ecc, CTRL, PMECC_CTRL_RST);
+ pmecc_writel(host->ecc, CTRL, PMECC_CTRL_DISABLE);
+
+ switch (host->tt) {
+ case 2:
+ val = PMECC_CFG_BCH_ERR2;
+ break;
+ case 4:
+ val = PMECC_CFG_BCH_ERR4;
+ break;
+ case 8:
+ val = PMECC_CFG_BCH_ERR8;
+ break;
+ case 12:
+ val = PMECC_CFG_BCH_ERR12;
+ break;
+ case 24:
+ val = PMECC_CFG_BCH_ERR24;
+ break;
+ }
+
+ if (host->board->sector_size == 512)
+ val |= PMECC_CFG_SECTOR512;
+ else if (host->board->sector_size == 1024)
+ val |= PMECC_CFG_SECTOR1024;
+
+ switch (host->sector_number) {
+ case 1:
+ val |= PMECC_CFG_PAGE_1SECTOR;
+ break;
+ case 2:
+ val |= PMECC_CFG_PAGE_2SECTORS;
+ break;
+ case 4:
+ val |= PMECC_CFG_PAGE_4SECTORS;
+ break;
+ case 8:
+ val |= PMECC_CFG_PAGE_8SECTORS;
+ break;
+ }
+
+ val |= PMECC_CFG_READ_OP | PMECC_CFG_SPARE_DISABLE
+ | PMECC_CFG_AUTO_DISABLE;
+ pmecc_writel(host->ecc, CFG, val);
+
+ ecc_layout = nand_chip->ecc.layout;
+ pmecc_writel(host->ecc, SAREA, mtd->oobsize - 1);
+ pmecc_writel(host->ecc, SADDR, ecc_layout->eccpos[0]);
+ pmecc_writel(host->ecc, EADDR,
+ ecc_layout->eccpos[ecc_layout->eccbytes - 1]);
+ /*
+ * FIXME : So far only 133MHz is clear specified in datasheet
+ * This may change in the future
+ */
+ pmecc_writel(host->ecc, CLK, PMECC_CLK_133MHZ);
+ pmecc_writel(host->ecc, IDR, 0xff);
+
+ pmecc_writel(host->ecc, CTRL, PMECC_CTRL_ENABLE);
+}
+
+static int __init atmel_pmecc_init_params(struct platform_device *pdev,
+ struct atmel_nand_host *host)
+{
+ struct mtd_info *mtd;
+ int cap, sector_size;
+ struct resource *regs;
+ struct nand_chip *nand_chip;
+ struct resource *regs_pmerr, *regs_rom;
+
+ cap = host->board->correction_cap;
+ sector_size = host->board->sector_size;
+ dev_info(host->dev, "Initialize PMECC params, cap: %d, sector: %d\n",
+ cap, sector_size);
+
+ /* Sanity check */
+ if ((sector_size != 512) && (sector_size != 1024)) {
+ dev_err(host->dev, "Unsupported PMECC sector size: %d;"
+ " Valid sector size is 512 or 1024 bytes\n",
+ host->board->sector_size);
+ goto err;
+ }
+ if ((cap != 2) && (cap != 4) && (cap != 8) && (cap != 12) &&
+ (cap != 24)) {
+ dev_err(host->dev, "Unsupported PMECC correction capability,"
+ " Valid is either 2, 4, 8, 12 or 24\n");
+ goto err;
+ }
+
+ nand_chip = &host->nand_chip;
+ mtd = &host->mtd;
+
+ nand_chip->ecc.mode = NAND_ECC_SOFT; /* By default */
+
+ regs = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ if (hard_ecc && !regs) {
+ dev_warn(host->dev, "Can't get I/O resource regs\nFalling "
+ "back on software ECC\n");
+ return 0;
+ }
+
+ if (no_ecc)
+ nand_chip->ecc.mode = NAND_ECC_NONE;
+ if (hard_ecc && regs) {
+ host->ecc = ioremap(regs->start, resource_size(regs));
+ if (host->ecc == NULL) {
+ dev_err(host->dev, "atmel_nand: ioremap failed\n");
+ goto err_pmecc_ioremap;
+ }
+
+ regs_pmerr = platform_get_resource(pdev, IORESOURCE_MEM, 2);
+ regs_rom = platform_get_resource(pdev, IORESOURCE_MEM, 3);
+ if (regs_pmerr && regs_rom) {
+ host->pmerrloc_base = ioremap(regs_pmerr->start,
+ resource_size(regs_pmerr));
+ host->rom_base = ioremap(regs_rom->start,
+ resource_size(regs_rom));
+
+ if (host->pmerrloc_base && host->rom_base) {
+ nand_chip->ecc.mode = NAND_ECC_HW;
+ nand_chip->ecc.read_page =
+ atmel_nand_pmecc_read_page;
+ nand_chip->ecc.write_page =
+ atmel_nand_pmecc_write_page;
+ } else {
+ dev_err(host->dev, "Can not get I/O resource"
+ " for HW PMECC controller!\n");
+ goto err_pmloc_ioremap;
+ }
+ }
+
+ if (nand_chip->ecc.mode != NAND_ECC_HW) {
+ dev_err(host->dev, "Can not get I/O resource"
+ " for HW ECC Rolling back to software ECC\n");
+ return 0;
+ }
+ }
+
+ if (nand_chip->ecc.mode == NAND_ECC_HW) {
+ /* ECC is calculated for the whole page (1 step) */
+ nand_chip->ecc.size = mtd->writesize;
+
+ /* set ECC page size and oob layout */
+ switch (mtd->writesize) {
+ case 2048:
+ host->mm = GF_DIMENSION_13;
+ host->nn = (1 << host->mm) - 1;
+ host->tt = cap;
+ host->sector_number = mtd->writesize / sector_size;
+ host->ecc_bytes_per_sector = pmecc_get_ecc_bytes(
+ host->tt, sector_size);
+ host->alpha_to = pmecc_get_alpha_to(host);
+ host->index_of = pmecc_get_index_of(host);
+
+ nand_chip->ecc.steps = 1;
+ nand_chip->ecc.bytes = host->ecc_bytes_per_sector *
+ host->sector_number;
+ if (nand_chip->ecc.bytes > mtd->oobsize - 2) {
+ dev_err(host->dev, "No room for ECC bytes\n");
+ goto err;
+ }
+ nand_chip->ecc.layout = &atmel_pmecc_oobinfo;
+ pmecc_config_ecc_layout(nand_chip->ecc.layout,
+ mtd->oobsize,
+ nand_chip->ecc.bytes);
+ break;
+ case 512:
+ case 1024:
+ case 4096:
+ /* TODO */
+ dev_warn(host->dev, "Only 2048 page size is currently"
+ "supported for PMECC, back to Software ECC\n");
+ default:
+ /* page size not handled by HW ECC */
+ /* switching back to soft ECC */
+ nand_chip->ecc.mode = NAND_ECC_SOFT;
+ nand_chip->ecc.calculate = NULL;
+ nand_chip->ecc.correct = NULL;
+ nand_chip->ecc.hwctl = NULL;
+ nand_chip->ecc.read_page = NULL;
+ nand_chip->ecc.postpad = 0;
+ nand_chip->ecc.prepad = 0;
+ nand_chip->ecc.bytes = 0;
+ break;
+ }
+ }
+
+ /* Initialize PMECC core if applicable */
+ if ((nand_chip->ecc.mode == NAND_ECC_HW) && cpu_has_pmecc())
+ atmel_pmecc_core_init(mtd);
+
+ return 0;
+
+err:
+err_pmloc_ioremap:
+ iounmap(host->ecc);
+ if (host->pmerrloc_base)
+ iounmap(host->pmerrloc_base);
+ if (host->rom_base)
+ iounmap(host->rom_base);
+err_pmecc_ioremap:
+ return -EIO;
+}
--
1.7.3.3
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