[U-Boot] [PATCH 02/18] sf: call spi_claim_bus() and spi_release_bus() only once per read, write or erase
Cyrille Pitchen
cyrille.pitchen at atmel.com
Tue Mar 15 19:12:24 CET 2016
There is no need to claim/release the SPI bus for each command sent to the
memory when performing read, write or erase operations. Now we claim the
SPI bus once for all at the very beginning of these operations then we
release it just before exiting.
Signed-off-by: Cyrille Pitchen <cyrille.pitchen at atmel.com>
---
drivers/mtd/spi/sf_internal.h | 5 +---
drivers/mtd/spi/spi_flash.c | 68 +++++++++++++++++++++++++------------------
2 files changed, 40 insertions(+), 33 deletions(-)
diff --git a/drivers/mtd/spi/sf_internal.h b/drivers/mtd/spi/sf_internal.h
index 7418c76b272c..dd8152721fe1 100644
--- a/drivers/mtd/spi/sf_internal.h
+++ b/drivers/mtd/spi/sf_internal.h
@@ -192,11 +192,9 @@ static inline int spi_flash_cmd_write_disable(struct spi_flash *flash)
/*
* Used for spi_flash write operation
- * - SPI claim
* - spi_flash_cmd_write_enable
* - spi_flash_cmd_write
* - spi_flash_cmd_wait_ready
- * - SPI release
*/
int spi_flash_write_common(struct spi_flash *flash, const u8 *cmd,
size_t cmd_len, const void *buf, size_t buf_len);
@@ -210,8 +208,7 @@ int spi_flash_cmd_write_ops(struct spi_flash *flash, u32 offset,
size_t len, const void *buf);
/*
- * Same as spi_flash_cmd_read() except it also claims/releases the SPI
- * bus. Used as common part of the ->read() operation.
+ * Same as spi_flash_cmd_read(). Used as common part of the ->read() operation.
*/
int spi_flash_read_common(struct spi_flash *flash, const u8 *cmd,
size_t cmd_len, void *data, size_t data_len);
diff --git a/drivers/mtd/spi/spi_flash.c b/drivers/mtd/spi/spi_flash.c
index e52728da9a09..740ecd44473a 100644
--- a/drivers/mtd/spi/spi_flash.c
+++ b/drivers/mtd/spi/spi_flash.c
@@ -261,12 +261,6 @@ int spi_flash_write_common(struct spi_flash *flash, const u8 *cmd,
if (buf == NULL)
timeout = SPI_FLASH_PAGE_ERASE_TIMEOUT;
- ret = spi_claim_bus(spi);
- if (ret) {
- debug("SF: unable to claim SPI bus\n");
- return ret;
- }
-
ret = spi_flash_cmd_write_enable(flash);
if (ret < 0) {
debug("SF: enabling write failed\n");
@@ -287,13 +281,12 @@ int spi_flash_write_common(struct spi_flash *flash, const u8 *cmd,
return ret;
}
- spi_release_bus(spi);
-
return ret;
}
int spi_flash_cmd_erase_ops(struct spi_flash *flash, u32 offset, size_t len)
{
+ struct spi_slave *spi = flash->spi;
u32 erase_size, erase_addr;
u8 cmd[SPI_FLASH_CMD_LEN];
int ret = -1;
@@ -304,11 +297,18 @@ int spi_flash_cmd_erase_ops(struct spi_flash *flash, u32 offset, size_t len)
return -1;
}
+ ret = spi_claim_bus(spi);
+ if (ret) {
+ debug("SF: unable to claim SPI bus\n");
+ return ret;
+ }
+
if (flash->flash_is_locked) {
if (flash->flash_is_locked(flash, offset, len) > 0) {
printf("offset 0x%x is protected and cannot be erased\n",
offset);
- return -EINVAL;
+ ret = -EINVAL;
+ goto release;
}
}
@@ -323,7 +323,7 @@ int spi_flash_cmd_erase_ops(struct spi_flash *flash, u32 offset, size_t len)
#ifdef CONFIG_SPI_FLASH_BAR
ret = spi_flash_write_bar(flash, erase_addr);
if (ret < 0)
- return ret;
+ break;
#endif
spi_flash_addr(erase_addr, cmd);
@@ -340,6 +340,9 @@ int spi_flash_cmd_erase_ops(struct spi_flash *flash, u32 offset, size_t len)
len -= erase_size;
}
+release:
+ spi_release_bus(spi);
+
return ret;
}
@@ -355,11 +358,18 @@ int spi_flash_cmd_write_ops(struct spi_flash *flash, u32 offset,
page_size = flash->page_size;
+ ret = spi_claim_bus(spi);
+ if (ret) {
+ debug("SF: unable to claim SPI bus\n");
+ return ret;
+ }
+
if (flash->flash_is_locked) {
if (flash->flash_is_locked(flash, offset, len) > 0) {
printf("offset 0x%x is protected and cannot be written\n",
offset);
- return -EINVAL;
+ ret = -EINVAL;
+ goto release;
}
}
@@ -374,7 +384,7 @@ int spi_flash_cmd_write_ops(struct spi_flash *flash, u32 offset,
#ifdef CONFIG_SPI_FLASH_BAR
ret = spi_flash_write_bar(flash, write_addr);
if (ret < 0)
- return ret;
+ break;
#endif
byte_addr = offset % page_size;
chunk_len = min(len - actual, (size_t)(page_size - byte_addr));
@@ -398,6 +408,9 @@ int spi_flash_cmd_write_ops(struct spi_flash *flash, u32 offset,
offset += chunk_len;
}
+release:
+ spi_release_bus(spi);
+
return ret;
}
@@ -407,20 +420,12 @@ int spi_flash_read_common(struct spi_flash *flash, const u8 *cmd,
struct spi_slave *spi = flash->spi;
int ret;
- ret = spi_claim_bus(spi);
- if (ret) {
- debug("SF: unable to claim SPI bus\n");
- return ret;
- }
-
ret = spi_flash_cmd_read(spi, cmd, cmd_len, data, data_len);
if (ret < 0) {
debug("SF: read cmd failed\n");
return ret;
}
- spi_release_bus(spi);
-
return ret;
}
@@ -446,25 +451,26 @@ int spi_flash_cmd_read_ops(struct spi_flash *flash, u32 offset,
int bank_sel = 0;
int ret = -1;
+ ret = spi_claim_bus(spi);
+ if (ret) {
+ debug("SF: unable to claim SPI bus\n");
+ return ret;
+ }
+
/* Handle memory-mapped SPI */
if (flash->memory_map) {
- ret = spi_claim_bus(spi);
- if (ret) {
- debug("SF: unable to claim SPI bus\n");
- return ret;
- }
spi_xfer(spi, 0, NULL, NULL, SPI_XFER_MMAP);
spi_flash_copy_mmap(data, flash->memory_map + offset, len);
spi_xfer(spi, 0, NULL, NULL, SPI_XFER_MMAP_END);
- spi_release_bus(spi);
- return 0;
+ goto release;
}
cmdsz = SPI_FLASH_CMD_LEN + flash->dummy_byte;
cmd = calloc(1, cmdsz);
if (!cmd) {
debug("SF: Failed to allocate cmd\n");
- return -ENOMEM;
+ ret = -ENOMEM;
+ goto release;
}
cmd[0] = flash->read_cmd;
@@ -478,7 +484,7 @@ int spi_flash_cmd_read_ops(struct spi_flash *flash, u32 offset,
#ifdef CONFIG_SPI_FLASH_BAR
ret = spi_flash_write_bar(flash, read_addr);
if (ret < 0)
- return ret;
+ break;
bank_sel = flash->bank_curr;
#endif
remain_len = ((SPI_FLASH_16MB_BOUN << flash->shift) *
@@ -502,6 +508,10 @@ int spi_flash_cmd_read_ops(struct spi_flash *flash, u32 offset,
}
free(cmd);
+
+release:
+ spi_release_bus(spi);
+
return ret;
}
--
1.8.2.2
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