From 2a6cc58869305f346e389eefdfa96dea5146cb0c Mon Sep 17 00:00:00 2001 From: Todor I Mollov Date: Sat, 4 Apr 2009 07:14:44 -0400 Subject: sf: atmel: implement power-of-two write/erase funcs Signed-off-by: Todor I Mollov Signed-off-by: Mike Frysinger CC: Haavard Skinnemoen --- drivers/mtd/spi/atmel.c | 139 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 139 insertions(+) (limited to 'drivers/mtd/spi') diff --git a/drivers/mtd/spi/atmel.c b/drivers/mtd/spi/atmel.c index c3b936f16a..3bc2dff8b2 100644 --- a/drivers/mtd/spi/atmel.c +++ b/drivers/mtd/spi/atmel.c @@ -196,6 +196,75 @@ static int dataflash_read_fast_at45(struct spi_flash *flash, return spi_flash_read_common(flash, cmd, sizeof(cmd), buf, len); } +/* + * TODO: the two write funcs (_p2/_at45) should get unified ... + */ +static int dataflash_write_p2(struct spi_flash *flash, + u32 offset, size_t len, const void *buf) +{ + struct atmel_spi_flash *asf = to_atmel_spi_flash(flash); + unsigned long page_size; + u32 addr = offset; + size_t chunk_len; + size_t actual; + int ret; + u8 cmd[4]; + + /* + * TODO: This function currently uses only page buffer #1. We can + * speed this up by using both buffers and loading one buffer while + * the other is being programmed into main memory. + */ + + page_size = (1 << asf->params->l2_page_size); + + ret = spi_claim_bus(flash->spi); + if (ret) { + debug("SF: Unable to claim SPI bus\n"); + return ret; + } + + for (actual = 0; actual < len; actual += chunk_len) { + chunk_len = min(len - actual, page_size - (addr % page_size)); + + /* Use the same address bits for both commands */ + cmd[0] = CMD_AT45_LOAD_BUF1; + cmd[1] = addr >> 16; + cmd[2] = addr >> 8; + cmd[3] = addr; + + ret = spi_flash_cmd_write(flash->spi, cmd, 4, + buf + actual, chunk_len); + if (ret < 0) { + debug("SF: Loading AT45 buffer failed\n"); + goto out; + } + + cmd[0] = CMD_AT45_PROG_BUF1; + ret = spi_flash_cmd_write(flash->spi, cmd, 4, NULL, 0); + if (ret < 0) { + debug("SF: AT45 page programming failed\n"); + goto out; + } + + ret = at45_wait_ready(flash, SPI_FLASH_PROG_TIMEOUT); + if (ret < 0) { + debug("SF: AT45 page programming timed out\n"); + goto out; + } + + addr += chunk_len; + } + + debug("SF: AT45: Successfully programmed %zu bytes @ 0x%x\n", + len, offset); + ret = 0; + +out: + spi_release_bus(flash->spi); + return ret; +} + static int dataflash_write_at45(struct spi_flash *flash, u32 offset, size_t len, const void *buf) { @@ -209,6 +278,12 @@ static int dataflash_write_at45(struct spi_flash *flash, int ret; u8 cmd[4]; + /* + * TODO: This function currently uses only page buffer #1. We can + * speed this up by using both buffers and loading one buffer while + * the other is being programmed into main memory. + */ + page_shift = asf->params->l2_page_size; page_size = (1 << page_shift) + (1 << (page_shift - 5)); page_shift++; @@ -263,6 +338,68 @@ out: return ret; } +/* + * TODO: the two erase funcs (_p2/_at45) should get unified ... + */ +int dataflash_erase_p2(struct spi_flash *flash, u32 offset, size_t len) +{ + struct atmel_spi_flash *asf = to_atmel_spi_flash(flash); + unsigned long page_size; + + size_t actual; + int ret; + u8 cmd[4]; + + /* + * TODO: This function currently uses page erase only. We can + * probably speed things up by using block and/or sector erase + * when possible. + */ + + page_size = (1 << asf->params->l2_page_size); + + if (offset % page_size || len % page_size) { + debug("SF: Erase offset/length not multiple of page size\n"); + return -1; + } + + cmd[0] = CMD_AT45_ERASE_PAGE; + cmd[3] = 0x00; + + ret = spi_claim_bus(flash->spi); + if (ret) { + debug("SF: Unable to claim SPI bus\n"); + return ret; + } + + for (actual = 0; actual < len; actual += page_size) { + cmd[1] = offset >> 16; + cmd[2] = offset >> 8; + + ret = spi_flash_cmd_write(flash->spi, cmd, 4, NULL, 0); + if (ret < 0) { + debug("SF: AT45 page erase failed\n"); + goto out; + } + + ret = at45_wait_ready(flash, SPI_FLASH_PAGE_ERASE_TIMEOUT); + if (ret < 0) { + debug("SF: AT45 page erase timed out\n"); + goto out; + } + + offset += page_size; + } + + debug("SF: AT45: Successfully erased %zu bytes @ 0x%x\n", + len, offset); + ret = 0; + +out: + spi_release_bus(flash->spi); + return ret; +} + int dataflash_erase_at45(struct spi_flash *flash, u32 offset, size_t len) { struct atmel_spi_flash *asf = to_atmel_spi_flash(flash); @@ -382,6 +519,8 @@ struct spi_flash *spi_flash_probe_atmel(struct spi_slave *spi, u8 *idcode) page_size += 1 << (params->l2_page_size - 5); } else { asf->flash.read = dataflash_read_fast_p2; + asf->flash.write = dataflash_write_p2; + asf->flash.erase = dataflash_erase_p2; } break; -- cgit v1.2.1