From 29d1e6f7810982d2c8f057ae35a39c2ac0cf484b Mon Sep 17 00:00:00 2001 From: Cyril Bur Date: Tue, 23 Jun 2015 13:22:13 +1000 Subject: libflash/blocklevel: add a smart write function which wraps up eraseing and writing For consumers who can't do better or who aren't to phased about performance, having to book keep erasing in order to be able to write data can be painful. Blocklevel can do it, possibly naively but its a convenience function Reviewed-By: Alistair Popple Signed-off-by: Cyril Bur Signed-off-by: Stewart Smith --- libflash/blocklevel.c | 71 +++++++++++++++++++++++++++++++++++++++++++++++++++ libflash/blocklevel.h | 3 +++ 2 files changed, 74 insertions(+) (limited to 'libflash') diff --git a/libflash/blocklevel.c b/libflash/blocklevel.c index 002bb8b..d9be775 100644 --- a/libflash/blocklevel.c +++ b/libflash/blocklevel.c @@ -158,6 +158,77 @@ int blocklevel_get_info(struct blocklevel_device *bl, const char **name, uint32_ return rc; } +int blocklevel_smart_write(struct blocklevel_device *bl, uint32_t pos, const void *buf, uint32_t len) +{ + uint32_t erase_size; + const void *write_buf = buf; + void *write_buf_start = NULL; + void *erase_buf; + int rc = 0; + + if (!write_buf || !bl) { + errno = EINVAL; + return FLASH_ERR_PARM_ERROR; + } + + if (!(bl->flags & WRITE_NEED_ERASE)) + return blocklevel_write(bl, pos, buf, len); + + rc = blocklevel_get_info(bl, NULL, NULL, &erase_size); + if (rc) + return rc; + + if (ecc_protected(bl, pos, len)) { + len = ecc_buffer_size(len); + + write_buf_start = malloc(len); + if (!write_buf_start) { + errno = ENOMEM; + return FLASH_ERR_MALLOC_FAILED; + } + + if (memcpy_to_ecc(write_buf_start, buf, ecc_buffer_size_minus_ecc(len))) { + free(write_buf_start); + errno = EBADF; + return FLASH_ERR_ECC_INVALID; + } + write_buf = write_buf_start; + } + + erase_buf = malloc(erase_size); + if (!erase_buf) { + errno = ENOMEM; + rc = FLASH_ERR_MALLOC_FAILED; + goto out; + } + + while (len > 0) { + uint32_t erase_block = pos & ~(erase_size - 1); + uint32_t block_offset = pos & (erase_size - 1); + uint32_t size = erase_size > len ? len : erase_size; + + rc = bl->read(bl, erase_block, erase_buf, erase_size); + if (rc) + goto out; + + if (memcmp(erase_buf + block_offset, write_buf, size) != 0) { + memcpy(erase_buf + block_offset, write_buf, size); + rc = bl->write(bl, erase_block, erase_buf + block_offset, size); + if (rc) + goto out; + } + + len -= size; + pos += size; + write_buf += size; + } + +out: + free(write_buf_start); + free(erase_buf); + return rc; +} + static int insert_bl_prot_range(struct blocklevel_range *ranges, struct bl_prot_range range) { struct bl_prot_range *new_ranges; diff --git a/libflash/blocklevel.h b/libflash/blocklevel.h index 310e274..e9a1978 100644 --- a/libflash/blocklevel.h +++ b/libflash/blocklevel.h @@ -60,6 +60,9 @@ int blocklevel_erase(struct blocklevel_device *bl, uint32_t pos, uint32_t len); int blocklevel_get_info(struct blocklevel_device *bl, const char **name, uint32_t *total_size, uint32_t *erase_granule); +/* Convienience functions */ +int blocklevel_smart_write(struct blocklevel_device *bl, uint32_t pos, const void *buf, uint32_t len); + /* Implemented in software at this level */ int blocklevel_ecc_protect(struct blocklevel_device *bl, uint32_t start, uint32_t len); -- cgit v1.1