[07/13] android: persistent_ram: refactor ecc support

Message ID	1331157503-3413-8-git-send-email-john.stultz@linaro.org
State	Superseded
Headers	show Return-Path: <patch+caf_=linaro-patchwork=canonical.com@linaro.org> Received-SPF: pass (google.com: domain of jstultz@us.ibm.com designates 32.97.110.153 as permitted sender) client-ip=32.97.110.153; Gateway: Authorized Use Only! Violators will be prosecuted for <patches@linaro.org> from <jstultz@us.ibm.com>; Wed, 7 Mar 2012 14:58:41 -0700 Gateway: Authorized Use Only! Violators will be prosecuted; Wed, 7 Mar 2012 14:58:39 -0700 From: John Stultz <john.stultz@linaro.org> To: lkml <linux-kernel@vger.kernel.org> Cc: Colin Cross <ccross@android.com>, Greg KH <gregkh@linuxfoundation.org>, Android Kernel Team <kernel-team@android.com>, John Stultz <john.stultz@linaro.org> Subject: [PATCH 07/13] android: persistent_ram: refactor ecc support Date: Wed, 7 Mar 2012 13:58:17 -0800 Message-Id: <1331157503-3413-8-git-send-email-john.stultz@linaro.org> In-Reply-To: <1331157503-3413-1-git-send-email-john.stultz@linaro.org> References: <1331157503-3413-1-git-send-email-john.stultz@linaro.org>

diff --git a/drivers/staging/android/Kconfig b/drivers/staging/android/Kconfig index 3f7dbc5..08a3b11 100644 --- a/drivers/staging/android/Kconfig +++ b/drivers/staging/android/Kconfig @@ -27,6 +27,9 @@ config ANDROID_LOGGER config ANDROID_PERSISTENT_RAM bool + select REED_SOLOMON + select REED_SOLOMON_ENC8 + select REED_SOLOMON_DEC8 config ANDROID_RAM_CONSOLE bool "Android RAM buffer console" @@ -34,40 +37,6 @@ config ANDROID_RAM_CONSOLE select ANDROID_PERSISTENT_RAM default n -menuconfig ANDROID_RAM_CONSOLE_ERROR_CORRECTION - bool "Android RAM Console Enable error correction" - default n - depends on ANDROID_PERSISTENT_RAM - select REED_SOLOMON - select REED_SOLOMON_ENC8 - select REED_SOLOMON_DEC8 - -if ANDROID_RAM_CONSOLE_ERROR_CORRECTION - -config ANDROID_RAM_CONSOLE_ERROR_CORRECTION_DATA_SIZE - int "Android RAM Console Data data size" - default 128 - help - Must be a power of 2. - -config ANDROID_RAM_CONSOLE_ERROR_CORRECTION_ECC_SIZE - int "Android RAM Console ECC size" - default 16 - -config ANDROID_RAM_CONSOLE_ERROR_CORRECTION_SYMBOL_SIZE - int "Android RAM Console Symbol size" - default 8 - -config ANDROID_RAM_CONSOLE_ERROR_CORRECTION_POLYNOMIAL - hex "Android RAM Console Polynomial" - default 0x19 if (ANDROID_RAM_CONSOLE_ERROR_CORRECTION_SYMBOL_SIZE = 4) - default 0x29 if (ANDROID_RAM_CONSOLE_ERROR_CORRECTION_SYMBOL_SIZE = 5) - default 0x61 if (ANDROID_RAM_CONSOLE_ERROR_CORRECTION_SYMBOL_SIZE = 6) - default 0x89 if (ANDROID_RAM_CONSOLE_ERROR_CORRECTION_SYMBOL_SIZE = 7) - default 0x11d if (ANDROID_RAM_CONSOLE_ERROR_CORRECTION_SYMBOL_SIZE = 8) - -endif # ANDROID_RAM_CONSOLE_ERROR_CORRECTION - config ANDROID_TIMED_OUTPUT bool "Timed output class driver" default y diff --git a/drivers/staging/android/persistent_ram.c b/drivers/staging/android/persistent_ram.c index d0f4666..35c57a0 100644 --- a/drivers/staging/android/persistent_ram.c +++ b/drivers/staging/android/persistent_ram.c @@ -16,13 +16,10 @@ #include <linux/kernel.h> #include <linux/init.h> #include <linux/io.h> +#include <linux/rslib.h> #include <linux/slab.h> #include "persistent_ram.h" -#ifdef CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION -#include <linux/rslib.h> -#endif - struct persistent_ram_buffer { uint32_t sig; uint32_t start; @@ -34,21 +31,16 @@ struct persistent_ram_buffer { static LIST_HEAD(zone_list); -#define ECC_BLOCK_SIZE CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION_DATA_SIZE -#define ECC_SIZE CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION_ECC_SIZE -#define ECC_SYMSIZE CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION_SYMBOL_SIZE -#define ECC_POLY CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION_POLYNOMIAL - -#ifdef CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION static void persistent_ram_encode_rs8(struct persistent_ram_zone *prz, uint8_t *data, size_t len, uint8_t *ecc) { int i; - uint16_t par[ECC_SIZE]; + uint16_t par[prz->ecc_size]; + /* Initialize the parity buffer */ memset(par, 0, sizeof(par)); encode_rs8(prz->rs_decoder, data, len, par, 0); - for (i = 0; i < ECC_SIZE; i++) + for (i = 0; i < prz->ecc_size; i++) ecc[i] = par[i]; } @@ -56,84 +48,167 @@ static int persistent_ram_decode_rs8(struct persistent_ram_zone *prz, void *data, size_t len, uint8_t *ecc) { int i; - uint16_t par[ECC_SIZE]; - for (i = 0; i < ECC_SIZE; i++) + uint16_t par[prz->ecc_size]; + + for (i = 0; i < prz->ecc_size; i++) par[i] = ecc[i]; return decode_rs8(prz->rs_decoder, data, par, len, NULL, 0, NULL, 0, NULL); } -#endif -static void persistent_ram_update(struct persistent_ram_zone *prz, - const void *s, unsigned int count) +static void persistent_ram_update_ecc(struct persistent_ram_zone *prz, + unsigned int count) { struct persistent_ram_buffer *buffer = prz->buffer; -#ifdef CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION uint8_t *buffer_end = buffer->data + prz->buffer_size; uint8_t *block; uint8_t *par; - int size = ECC_BLOCK_SIZE; -#endif - memcpy(buffer->data + buffer->start, s, count); -#ifdef CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION - block = buffer->data + (buffer->start & ~(ECC_BLOCK_SIZE - 1)); + int ecc_block_size = prz->ecc_block_size; + int ecc_size = prz->ecc_size; + int size = prz->ecc_block_size; + + if (!prz->ecc) + return; + + block = buffer->data + (buffer->start & ~(ecc_block_size - 1)); par = prz->par_buffer + - (buffer->start / ECC_BLOCK_SIZE) * ECC_SIZE; + (buffer->start / ecc_block_size) * prz->ecc_size; do { - if (block + ECC_BLOCK_SIZE > buffer_end) + if (block + ecc_block_size > buffer_end) size = buffer_end - block; persistent_ram_encode_rs8(prz, block, size, par); - block += ECC_BLOCK_SIZE; - par += ECC_SIZE; + block += ecc_block_size; + par += ecc_size; } while (block < buffer->data + buffer->start + count); -#endif } -static void persistent_ram_update_header(struct persistent_ram_zone *prz) +static void persistent_ram_update_header_ecc(struct persistent_ram_zone *prz) { -#ifdef CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION struct persistent_ram_buffer *buffer = prz->buffer; + if (!prz->ecc) + return; + persistent_ram_encode_rs8(prz, (uint8_t *)buffer, sizeof(*buffer), prz->par_header); -#endif } -static void __init -persistent_ram_save_old(struct persistent_ram_zone *prz) +static void persistent_ram_ecc_old(struct persistent_ram_zone *prz) { struct persistent_ram_buffer *buffer = prz->buffer; - size_t old_log_size = buffer->size; - char *dest; -#ifdef CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION uint8_t *block; uint8_t *par; + if (!prz->ecc) + return; + block = buffer->data; par = prz->par_buffer; while (block < buffer->data + buffer->size) { int numerr; - int size = ECC_BLOCK_SIZE; + int size = prz->ecc_block_size; if (block + size > buffer->data + prz->buffer_size) size = buffer->data + prz->buffer_size - block; numerr = persistent_ram_decode_rs8(prz, block, size, par); if (numerr > 0) { -#if 0 - pr_info("persistent_ram: error in block %p, %d\n", + pr_devel("persistent_ram: error in block %p, %d\n", block, numerr); -#endif prz->corrected_bytes += numerr; } else if (numerr < 0) { -#if 0 - pr_info("persistent_ram: uncorrectable error in block %p\n", + pr_devel("persistent_ram: uncorrectable error in block %p\n", block); -#endif prz->bad_blocks++; } - block += ECC_BLOCK_SIZE; - par += ECC_SIZE; + block += prz->ecc_block_size; + par += prz->ecc_size; + } +} + +static int persistent_ram_init_ecc(struct persistent_ram_zone *prz, + size_t buffer_size) +{ + int numerr; + struct persistent_ram_buffer *buffer = prz->buffer; + int ecc_blocks; + + if (!prz->ecc) + return 0; + + prz->ecc_block_size = 128; + prz->ecc_size = 16; + prz->ecc_symsize = 8; + prz->ecc_poly = 0x11d; + + ecc_blocks = DIV_ROUND_UP(prz->buffer_size, prz->ecc_block_size); + prz->buffer_size -= (ecc_blocks + 1) * prz->ecc_size; + + if (prz->buffer_size > buffer_size) { + pr_err("persistent_ram: invalid size %zu, non-ecc datasize %zu\n", + buffer_size, prz->buffer_size); + return -EINVAL; + } + + prz->par_buffer = buffer->data + prz->buffer_size; + prz->par_header = prz->par_buffer + ecc_blocks * prz->ecc_size; + + /* + * first consecutive root is 0 + * primitive element to generate roots = 1 + */ + prz->rs_decoder = init_rs(prz->ecc_symsize, prz->ecc_poly, 0, 1, + prz->ecc_size); + if (prz->rs_decoder == NULL) { + pr_info("persistent_ram: init_rs failed\n"); + return -EINVAL; } -#endif + + prz->corrected_bytes = 0; + prz->bad_blocks = 0; + + numerr = persistent_ram_decode_rs8(prz, buffer, sizeof(*buffer), + prz->par_header); + if (numerr > 0) { + pr_info("persistent_ram: error in header, %d\n", numerr); + prz->corrected_bytes += numerr; + } else if (numerr < 0) { + pr_info("persistent_ram: uncorrectable error in header\n"); + prz->bad_blocks++; + } + + return 0; +} + +ssize_t persistent_ram_ecc_string(struct persistent_ram_zone *prz, + char *str, size_t len) +{ + ssize_t ret; + + if (prz->corrected_bytes || prz->bad_blocks) + ret = snprintf(str, len, "" + "\n%d Corrected bytes, %d unrecoverable blocks\n", + prz->corrected_bytes, prz->bad_blocks); + else + ret = snprintf(str, len, "\nNo errors detected\n"); + + return ret; +} + +static void persistent_ram_update(struct persistent_ram_zone *prz, + const void *s, unsigned int count) +{ + struct persistent_ram_buffer *buffer = prz->buffer; + memcpy(buffer->data + buffer->start, s, count); + persistent_ram_update_ecc(prz, count); +} + +static void __init +persistent_ram_save_old(struct persistent_ram_zone *prz) +{ + struct persistent_ram_buffer *buffer = prz->buffer; + size_t old_log_size = buffer->size; + char *dest; + + persistent_ram_ecc_old(prz); dest = kmalloc(old_log_size, GFP_KERNEL); if (dest == NULL) { @@ -173,30 +248,11 @@ int persistent_ram_write(struct persistent_ram_zone *prz, buffer->start += c; if (buffer->size < prz->buffer_size) buffer->size += c; - persistent_ram_update_header(prz); + persistent_ram_update_header_ecc(prz); return count; } -ssize_t persistent_ram_ecc_string(struct persistent_ram_zone *prz, - char *str, size_t len) -{ -#ifdef CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION - ssize_t ret; - - if (prz->corrected_bytes || prz->bad_blocks) - ret = snprintf(str, len, "" - "\n%d Corrected bytes, %d unrecoverable blocks\n", - prz->corrected_bytes, prz->bad_blocks); - else - ret = snprintf(str, len, "\nNo errors detected\n"); - - return ret; -#else - return 0; -#endif -} - size_t persistent_ram_old_size(struct persistent_ram_zone *prz) { return prz->old_log_size; @@ -215,12 +271,10 @@ void persistent_ram_free_old(struct persistent_ram_zone *prz) } static int __init __persistent_ram_init(struct persistent_ram_zone *prz, - void __iomem *mem, size_t buffer_size) + void __iomem *mem, size_t buffer_size, bool ecc) { struct persistent_ram_buffer *buffer = mem; -#ifdef CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION - int numerr; -#endif + int ret; INIT_LIST_HEAD(&prz->node); @@ -233,43 +287,10 @@ static int __init __persistent_ram_init(struct persistent_ram_zone *prz, return -EINVAL; } -#ifdef CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION - prz->buffer_size -= (DIV_ROUND_UP(prz->buffer_size, - ECC_BLOCK_SIZE) + 1) * ECC_SIZE; - - if (prz->buffer_size > buffer_size) { - pr_err("persistent_ram: buffer %p, invalid size %zu, non-ecc datasize %zu\n", - buffer, buffer_size, prz->buffer_size); - return -EINVAL; - } - - prz->par_buffer = buffer->data + prz->buffer_size; - prz->par_header = prz->par_buffer + - DIV_ROUND_UP(prz->buffer_size, ECC_BLOCK_SIZE) * ECC_SIZE; - - - /* first consecutive root is 0 - * primitive element to generate roots = 1 - */ - prz->rs_decoder = init_rs(ECC_SYMSIZE, ECC_POLY, 0, 1, ECC_SIZE); - if (prz->rs_decoder == NULL) { - pr_info("persistent_ram: init_rs failed\n"); - return -EINVAL; - } - - prz->corrected_bytes = 0; - prz->bad_blocks = 0; - - numerr = persistent_ram_decode_rs8(prz, buffer, sizeof(*buffer), - prz->par_header); - if (numerr > 0) { - pr_info("persistent_ram: error in header, %d\n", numerr); - prz->corrected_bytes += numerr; - } else if (numerr < 0) { - pr_info("persistent_ram: uncorrectable error in header\n"); - prz->bad_blocks++; - } -#endif + prz->ecc = ecc; + ret = persistent_ram_init_ecc(prz, buffer_size); + if (ret) + return ret; if (buffer->sig == PERSISTENT_RAM_SIG) { if (buffer->size > prz->buffer_size @@ -296,7 +317,7 @@ static int __init __persistent_ram_init(struct persistent_ram_zone *prz, } int __init persistent_ram_init_ringbuffer(struct persistent_ram_zone *prz, - void __iomem *mem, size_t buffer_size) + void __iomem *mem, size_t buffer_size, bool ecc) { - return __persistent_ram_init(prz, mem, buffer_size); + return __persistent_ram_init(prz, mem, buffer_size, true); } diff --git a/drivers/staging/android/persistent_ram.h b/drivers/staging/android/persistent_ram.h index f73fb08..ab3995c 100644 --- a/drivers/staging/android/persistent_ram.h +++ b/drivers/staging/android/persistent_ram.h @@ -24,13 +24,19 @@ struct persistent_ram_zone { struct list_head node; struct persistent_ram_buffer *buffer; size_t buffer_size; -#ifdef CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION + + /* ECC correction */ + bool ecc; char *par_buffer; char *par_header; struct rs_control *rs_decoder; int corrected_bytes; int bad_blocks; -#endif + int ecc_block_size; + int ecc_size; + int ecc_symsize; + int ecc_poly; + char *old_log; size_t old_log_size; size_t old_log_footer_size; @@ -38,7 +44,7 @@ struct persistent_ram_zone { }; int persistent_ram_init_ringbuffer(struct persistent_ram_zone *prz, - void __iomem *buffer, size_t buffer_size); + void __iomem *buffer, size_t buffer_size, bool ecc); int persistent_ram_write(struct persistent_ram_zone *prz, const void *s, unsigned int count); diff --git a/drivers/staging/android/ram_console.c b/drivers/staging/android/ram_console.c index 689c3dc..d920bd7 100644 --- a/drivers/staging/android/ram_console.c +++ b/drivers/staging/android/ram_console.c @@ -76,7 +76,7 @@ static int ram_console_driver_probe(struct platform_device *pdev) } ret = persistent_ram_init_ringbuffer(&ram_console_zone, buffer, - buffer_size); + buffer_size, true); if (ret) goto err;

[07/13] android: persistent_ram: refactor ecc support

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Patch