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author | Tom Rini <trini@ti.com> | 2013-11-25 10:42:13 -0500 |
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committer | Tom Rini <trini@ti.com> | 2013-11-25 10:42:13 -0500 |
commit | faca8ff55f4a2cf45fb906cc37f44601149fc00e (patch) | |
tree | 181e94fa3326f2ec97f0287f3bbbe54ccd3b13d1 /drivers/mtd/nand/omap_elm.c | |
parent | 5a4fe1aaf1210b02bb98e347993ffbcffeb4ffaa (diff) | |
parent | 2c17e6d1d996a1b8b9325de15f253a13d5877dee (diff) | |
download | u-boot-imx-faca8ff55f4a2cf45fb906cc37f44601149fc00e.zip u-boot-imx-faca8ff55f4a2cf45fb906cc37f44601149fc00e.tar.gz u-boot-imx-faca8ff55f4a2cf45fb906cc37f44601149fc00e.tar.bz2 |
Merge branch 'master' of git://git.denx.de/u-boot-nand-flash
Diffstat (limited to 'drivers/mtd/nand/omap_elm.c')
-rw-r--r-- | drivers/mtd/nand/omap_elm.c | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/drivers/mtd/nand/omap_elm.c b/drivers/mtd/nand/omap_elm.c new file mode 100644 index 0000000..2aa7807 --- /dev/null +++ b/drivers/mtd/nand/omap_elm.c @@ -0,0 +1,196 @@ +/* + * (C) Copyright 2010-2011 Texas Instruments, <www.ti.com> + * Mansoor Ahamed <mansoor.ahamed@ti.com> + * + * BCH Error Location Module (ELM) support. + * + * NOTE: + * 1. Supports only continuous mode. Dont see need for page mode in uboot + * 2. Supports only syndrome polynomial 0. i.e. poly local variable is + * always set to ELM_DEFAULT_POLY. Dont see need for other polynomial + * sets in uboot + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <asm/io.h> +#include <asm/errno.h> +#include <asm/arch/cpu.h> +#include <asm/omap_gpmc.h> +#include <asm/omap_elm.h> + +#define ELM_DEFAULT_POLY (0) + +struct elm *elm_cfg; + +/** + * elm_load_syndromes - Load BCH syndromes based on nibble selection + * @syndrome: BCH syndrome + * @nibbles: + * @poly: Syndrome Polynomial set to use + * + * Load BCH syndromes based on nibble selection + */ +static void elm_load_syndromes(u8 *syndrome, u32 nibbles, u8 poly) +{ + u32 *ptr; + u32 val; + + /* reg 0 */ + ptr = &elm_cfg->syndrome_fragments[poly].syndrome_fragment_x[0]; + val = syndrome[0] | (syndrome[1] << 8) | (syndrome[2] << 16) | + (syndrome[3] << 24); + writel(val, ptr); + /* reg 1 */ + ptr = &elm_cfg->syndrome_fragments[poly].syndrome_fragment_x[1]; + val = syndrome[4] | (syndrome[5] << 8) | (syndrome[6] << 16) | + (syndrome[7] << 24); + writel(val, ptr); + + /* BCH 8-bit with 26 nibbles (4*8=32) */ + if (nibbles > 13) { + /* reg 2 */ + ptr = &elm_cfg->syndrome_fragments[poly].syndrome_fragment_x[2]; + val = syndrome[8] | (syndrome[9] << 8) | (syndrome[10] << 16) | + (syndrome[11] << 24); + writel(val, ptr); + /* reg 3 */ + ptr = &elm_cfg->syndrome_fragments[poly].syndrome_fragment_x[3]; + val = syndrome[12] | (syndrome[13] << 8) | + (syndrome[14] << 16) | (syndrome[15] << 24); + writel(val, ptr); + } + + /* BCH 16-bit with 52 nibbles (7*8=56) */ + if (nibbles > 26) { + /* reg 4 */ + ptr = &elm_cfg->syndrome_fragments[poly].syndrome_fragment_x[4]; + val = syndrome[16] | (syndrome[17] << 8) | + (syndrome[18] << 16) | (syndrome[19] << 24); + writel(val, ptr); + + /* reg 5 */ + ptr = &elm_cfg->syndrome_fragments[poly].syndrome_fragment_x[5]; + val = syndrome[20] | (syndrome[21] << 8) | + (syndrome[22] << 16) | (syndrome[23] << 24); + writel(val, ptr); + + /* reg 6 */ + ptr = &elm_cfg->syndrome_fragments[poly].syndrome_fragment_x[6]; + val = syndrome[24] | (syndrome[25] << 8) | + (syndrome[26] << 16) | (syndrome[27] << 24); + writel(val, ptr); + } +} + +/** + * elm_check_errors - Check for BCH errors and return error locations + * @syndrome: BCH syndrome + * @nibbles: + * @error_count: Returns number of errrors in the syndrome + * @error_locations: Returns error locations (in decimal) in this array + * + * Check the provided syndrome for BCH errors and return error count + * and locations in the array passed. Returns -1 if error is not correctable, + * else returns 0 + */ +int elm_check_error(u8 *syndrome, u32 nibbles, u32 *error_count, + u32 *error_locations) +{ + u8 poly = ELM_DEFAULT_POLY; + s8 i; + u32 location_status; + + elm_load_syndromes(syndrome, nibbles, poly); + + /* start processing */ + writel((readl(&elm_cfg->syndrome_fragments[poly].syndrome_fragment_x[6]) + | ELM_SYNDROME_FRAGMENT_6_SYNDROME_VALID), + &elm_cfg->syndrome_fragments[poly].syndrome_fragment_x[6]); + + /* wait for processing to complete */ + while ((readl(&elm_cfg->irqstatus) & (0x1 << poly)) != 0x1) + ; + /* clear status */ + writel((readl(&elm_cfg->irqstatus) | (0x1 << poly)), + &elm_cfg->irqstatus); + + /* check if correctable */ + location_status = readl(&elm_cfg->error_location[poly].location_status); + if (!(location_status & ELM_LOCATION_STATUS_ECC_CORRECTABLE_MASK)) + return -1; + + /* get error count */ + *error_count = readl(&elm_cfg->error_location[poly].location_status) & + ELM_LOCATION_STATUS_ECC_NB_ERRORS_MASK; + + for (i = 0; i < *error_count; i++) { + error_locations[i] = + readl(&elm_cfg->error_location[poly].error_location_x[i]); + } + + return 0; +} + + +/** + * elm_config - Configure ELM module + * @level: 4 / 8 / 16 bit BCH + * + * Configure ELM module based on BCH level. + * Set mode as continuous mode. + * Currently we are using only syndrome 0 and syndromes 1 to 6 are not used. + * Also, the mode is set only for syndrome 0 + */ +int elm_config(enum bch_level level) +{ + u32 val; + u8 poly = ELM_DEFAULT_POLY; + u32 buffer_size = 0x7FF; + + /* config size and level */ + val = (u32)(level) & ELM_LOCATION_CONFIG_ECC_BCH_LEVEL_MASK; + val |= ((buffer_size << ELM_LOCATION_CONFIG_ECC_SIZE_POS) & + ELM_LOCATION_CONFIG_ECC_SIZE_MASK); + writel(val, &elm_cfg->location_config); + + /* config continous mode */ + /* enable interrupt generation for syndrome polynomial set */ + writel((readl(&elm_cfg->irqenable) | (0x1 << poly)), + &elm_cfg->irqenable); + /* set continuous mode for the syndrome polynomial set */ + writel((readl(&elm_cfg->page_ctrl) & ~(0x1 << poly)), + &elm_cfg->page_ctrl); + + return 0; +} + +/** + * elm_reset - Do a soft reset of ELM + * + * Perform a soft reset of ELM and return after reset is done. + */ +void elm_reset(void) +{ + /* initiate reset */ + writel((readl(&elm_cfg->sysconfig) | ELM_SYSCONFIG_SOFTRESET), + &elm_cfg->sysconfig); + + /* wait for reset complete and normal operation */ + while ((readl(&elm_cfg->sysstatus) & ELM_SYSSTATUS_RESETDONE) != + ELM_SYSSTATUS_RESETDONE) + ; +} + +/** + * elm_init - Initialize ELM module + * + * Initialize ELM support. Currently it does only base address init + * and ELM reset. + */ +void elm_init(void) +{ + elm_cfg = (struct elm *)ELM_BASE; + elm_reset(); +} |