sf: atmel: implement power-of-two write/erase funcs
Signed-off-by: Todor I Mollov <tmollov@ucsd.edu>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
CC: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
diff --git a/drivers/mtd/spi/atmel.c b/drivers/mtd/spi/atmel.c
index c3b936f..3bc2dff 100644
--- a/drivers/mtd/spi/atmel.c
+++ b/drivers/mtd/spi/atmel.c
@@ -196,6 +196,75 @@
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 @@
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 @@
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 @@
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;