Hello Aaron Durbin, Furquan Shaikh,
I'd like you to do a code review. Please visit
https://review.coreboot.org/c/coreboot/+/33282
to review the following change.
Change subject: spi_flash: Make .read() callback optional ......................................................................
spi_flash: Make .read() callback optional
All SPI flash chip drivers currently in coreboot use the generic read functions (spi_flash_cmd_read_fast()/_slow()) as their read callback. The only use case for specialized read callbacks we have left is with specialized flash controllers like Intel fast_spi (which sort of impersonate the flash chip driver by implementing their own probe function).
This patch unifies the behavior for all normal flash drivers by making the read callback optional and letting them all fall back to a default read implementation that handles normal fast/slow reading. Most of the drivers used to install the respective callback after checking CONFIG_SPI_FLASH_NO_FAST_READ, but some hardcoded either slow or fast writes. I have found no indications for why this is and spot-checked datasheets for affected vendors to make sure they all support both commands, so I assume this is just some old inaccuracy rather than important differences that need preserving. (Please yell if you disagree.)
Also take the opportunity to refactor some of the common spi_flash.c code a bit because I felt there are too many nested functions that don't really do enough on their own, and centralizing stuff a bit should make it easier to follow the code flow. (Some of this is in preparation for the next patch.)
Change-Id: I2096a3ce619767b41b1b0c0c2b8e95b2bd90a419 Signed-off-by: Julius Werner jwerner@chromium.org --- M src/drivers/spi/adesto.c M src/drivers/spi/amic.c M src/drivers/spi/atmel.c M src/drivers/spi/eon.c M src/drivers/spi/gigadevice.c M src/drivers/spi/macronix.c M src/drivers/spi/spansion.c M src/drivers/spi/spi_flash.c M src/drivers/spi/spi_flash_internal.h M src/drivers/spi/sst.c M src/drivers/spi/stmicro.c M src/drivers/spi/winbond.c 12 files changed, 34 insertions(+), 103 deletions(-)
git pull ssh://review.coreboot.org:29418/coreboot refs/changes/82/33282/1
diff --git a/src/drivers/spi/adesto.c b/src/drivers/spi/adesto.c index a805609..4e1043e 100644 --- a/src/drivers/spi/adesto.c +++ b/src/drivers/spi/adesto.c @@ -201,11 +201,6 @@ static const struct spi_flash_ops spi_flash_ops = { .write = adesto_write, .erase = spi_flash_cmd_erase, -#if CONFIG(SPI_FLASH_NO_FAST_READ) - .read = spi_flash_cmd_read_slow, -#else - .read = spi_flash_cmd_read_fast, -#endif };
int spi_flash_probe_adesto(const struct spi_slave *spi, u8 *idcode, diff --git a/src/drivers/spi/amic.c b/src/drivers/spi/amic.c index 64c91cc..b580dc3 100644 --- a/src/drivers/spi/amic.c +++ b/src/drivers/spi/amic.c @@ -176,11 +176,6 @@ static const struct spi_flash_ops spi_flash_ops = { .write = amic_write, .erase = spi_flash_cmd_erase, -#if CONFIG(SPI_FLASH_NO_FAST_READ) - .read = spi_flash_cmd_read_slow, -#else - .read = spi_flash_cmd_read_fast, -#endif };
int spi_flash_probe_amic(const struct spi_slave *spi, u8 *idcode, diff --git a/src/drivers/spi/atmel.c b/src/drivers/spi/atmel.c index 7d6e172..58a2862 100644 --- a/src/drivers/spi/atmel.c +++ b/src/drivers/spi/atmel.c @@ -157,11 +157,6 @@ static const struct spi_flash_ops spi_flash_ops = { .write = atmel_write, .erase = spi_flash_cmd_erase, -#if CONFIG(SPI_FLASH_NO_FAST_READ) - .read = spi_flash_cmd_read_slow, -#else - .read = spi_flash_cmd_read_fast, -#endif };
int spi_flash_probe_atmel(const struct spi_slave *spi, u8 *idcode, diff --git a/src/drivers/spi/eon.c b/src/drivers/spi/eon.c index 33e12a0..f3cf70e 100644 --- a/src/drivers/spi/eon.c +++ b/src/drivers/spi/eon.c @@ -292,7 +292,6 @@ .write = eon_write, .erase = spi_flash_cmd_erase, .status = spi_flash_cmd_status, - .read = spi_flash_cmd_read_fast, };
int spi_flash_probe_eon(const struct spi_slave *spi, u8 *idcode, diff --git a/src/drivers/spi/gigadevice.c b/src/drivers/spi/gigadevice.c index 83216c0..194c5ec 100644 --- a/src/drivers/spi/gigadevice.c +++ b/src/drivers/spi/gigadevice.c @@ -222,11 +222,6 @@ .write = gigadevice_write, .erase = spi_flash_cmd_erase, .status = spi_flash_cmd_status, -#if CONFIG(SPI_FLASH_NO_FAST_READ) - .read = spi_flash_cmd_read_slow, -#else - .read = spi_flash_cmd_read_fast, -#endif };
int spi_flash_probe_gigadevice(const struct spi_slave *spi, u8 *idcode, diff --git a/src/drivers/spi/macronix.c b/src/drivers/spi/macronix.c index 1610ca1..5a97b8f 100644 --- a/src/drivers/spi/macronix.c +++ b/src/drivers/spi/macronix.c @@ -268,11 +268,6 @@ .write = macronix_write, .erase = spi_flash_cmd_erase, .status = spi_flash_cmd_status, -#if CONFIG(SPI_FLASH_NO_FAST_READ) - .read = spi_flash_cmd_read_slow, -#else - .read = spi_flash_cmd_read_fast, -#endif };
int spi_flash_probe_macronix(const struct spi_slave *spi, u8 *idcode, diff --git a/src/drivers/spi/spansion.c b/src/drivers/spi/spansion.c index e687bf8..4a241ba 100644 --- a/src/drivers/spi/spansion.c +++ b/src/drivers/spi/spansion.c @@ -282,7 +282,6 @@ static const struct spi_flash_ops spi_flash_ops = { .write = spansion_write, .erase = spi_flash_cmd_erase, - .read = spi_flash_cmd_read_slow, .status = spi_flash_cmd_status, };
diff --git a/src/drivers/spi/spi_flash.c b/src/drivers/spi/spi_flash.c index ae1d2ef..d152027 100644 --- a/src/drivers/spi/spi_flash.c +++ b/src/drivers/spi/spi_flash.c @@ -31,7 +31,7 @@ static int do_spi_flash_cmd(const struct spi_slave *spi, const void *dout, size_t bytes_out, void *din, size_t bytes_in) { - int ret = 1; + int ret; /* * SPI flash requires command-response kind of behavior. Thus, two * separate SPI vectors are required -- first to transmit dout and other @@ -49,11 +49,10 @@ if (!bytes_in) count = 1;
- if (spi_claim_bus(spi)) + if ((ret = spi_claim_bus(spi))) return ret;
- if (spi_xfer_vector(spi, vectors, count) == 0) - ret = 0; + ret = spi_xfer_vector(spi, vectors, count);
spi_release_bus(spi); return ret; @@ -68,18 +67,6 @@ return ret; }
-static int spi_flash_cmd_read(const struct spi_slave *spi, const u8 *cmd, - size_t cmd_len, void *data, size_t data_len) -{ - int ret = do_spi_flash_cmd(spi, cmd, cmd_len, data, data_len); - if (ret) { - printk(BIOS_WARNING, "SF: Failed to send read command (%zu bytes): %d\n", - data_len, ret); - } - - return ret; -} - /* TODO: This code is quite possibly broken and overflowing stacks. Fix ASAP! */ #pragma GCC diagnostic push #if defined(__GNUC__) && !defined(__clang__) @@ -103,34 +90,38 @@ } #pragma GCC diagnostic pop
-static int spi_flash_cmd_read_array(const struct spi_slave *spi, u8 *cmd, - size_t cmd_len, u32 offset, - size_t len, void *data) -{ - spi_flash_addr(offset, cmd); - return spi_flash_cmd_read(spi, cmd, cmd_len, data, len); -} - /* Perform the read operation honoring spi controller fifo size, reissuing * the read command until the full request completed. */ -static int spi_flash_cmd_read_array_wrapped(const struct spi_slave *spi, - u8 *cmd, size_t cmd_len, u32 offset, - size_t len, void *buf) +static int spi_flash_read_chunked(const struct spi_flash *flash, u32 offset, + size_t len, void *buf) { - int ret; - size_t xfer_len; + u8 cmd[5]; + int ret, cmd_len; + int (*do_cmd)(const struct spi_slave *, const void *, size_t, + void *, size_t); + + if (CONFIG(SPI_FLASH_NO_FAST_READ)) { + cmd_len = 4; + cmd[0] = CMD_READ_ARRAY_SLOW; + do_cmd = do_spi_flash_cmd; + } else { + cmd_len = 5; + cmd[0] = CMD_READ_ARRAY_FAST; + cmd[4] = 0; + do_cmd = do_spi_flash_cmd; + } + uint8_t *data = buf; - while (len) { - xfer_len = spi_crop_chunk(spi, cmd_len, len); - - /* Perform the read. */ - ret = spi_flash_cmd_read_array(spi, cmd, cmd_len, - offset, xfer_len, data); - - if (ret) + size_t xfer_len = spi_crop_chunk(&flash->spi, sizeof(cmd), len); + spi_flash_addr(offset, cmd); + ret = do_cmd(&flash->spi, cmd, cmd_len, data, xfer_len); + if (ret) { + printk(BIOS_WARNING, + "SF: Failed to send read command %#.2x(%#x, %#zx): %d\n", + cmd[0], offset, xfer_len, ret); return ret; - + } offset += xfer_len; data += xfer_len; len -= xfer_len; @@ -139,28 +130,6 @@ return 0; }
-int spi_flash_cmd_read_fast(const struct spi_flash *flash, u32 offset, - size_t len, void *data) -{ - u8 cmd[5]; - - cmd[0] = CMD_READ_ARRAY_FAST; - cmd[4] = 0x00; - - return spi_flash_cmd_read_array_wrapped(&flash->spi, cmd, sizeof(cmd), - offset, len, data); -} - -int spi_flash_cmd_read_slow(const struct spi_flash *flash, u32 offset, - size_t len, void *data) -{ - u8 cmd[4]; - - cmd[0] = CMD_READ_ARRAY_SLOW; - return spi_flash_cmd_read_array_wrapped(&flash->spi, cmd, sizeof(cmd), - offset, len, data); -} - int spi_flash_cmd_poll_bit(const struct spi_flash *flash, unsigned long timeout, u8 cmd, u8 poll_bit) { @@ -174,7 +143,7 @@ mono_time_add_msecs(&end, timeout);
do { - ret = spi_flash_cmd_read(spi, &cmd, 1, &status, 1); + ret = do_spi_flash_cmd(spi, &cmd, 1, &status, 1); if (ret) return -1; if ((status & poll_bit) == 0) @@ -391,7 +360,10 @@ int spi_flash_read(const struct spi_flash *flash, u32 offset, size_t len, void *buf) { - return flash->ops->read(flash, offset, len, buf); + if (flash->ops->read) + return flash->ops->read(flash, offset, len, buf); + + return spi_flash_read_chunked(flash, offset, len, buf); }
int spi_flash_write(const struct spi_flash *flash, u32 offset, size_t len, diff --git a/src/drivers/spi/spi_flash_internal.h b/src/drivers/spi/spi_flash_internal.h index a89610a..f15c737 100644 --- a/src/drivers/spi/spi_flash_internal.h +++ b/src/drivers/spi/spi_flash_internal.h @@ -34,12 +34,6 @@ /* Send a single-byte command to the device and read the response */ int spi_flash_cmd(const struct spi_slave *spi, u8 cmd, void *response, size_t len);
-int spi_flash_cmd_read_fast(const struct spi_flash *flash, u32 offset, - size_t len, void *data); - -int spi_flash_cmd_read_slow(const struct spi_flash *flash, u32 offset, - size_t len, void *data); - /* * Send a multi-byte command to the device followed by (optional) * data. Used for programming the flash array, etc. diff --git a/src/drivers/spi/sst.c b/src/drivers/spi/sst.c index e4ea7805..abe3f2a 100644 --- a/src/drivers/spi/sst.c +++ b/src/drivers/spi/sst.c @@ -55,14 +55,12 @@ .write = sst_write_ai, .erase = spi_flash_cmd_erase, .status = spi_flash_cmd_status, - .read = spi_flash_cmd_read_fast, };
static const struct spi_flash_ops spi_flash_ops_write_256 = { .write = sst_write_256, .erase = spi_flash_cmd_erase, .status = spi_flash_cmd_status, - .read = spi_flash_cmd_read_fast, };
#define SST_SECTOR_SIZE (4 * 1024) diff --git a/src/drivers/spi/stmicro.c b/src/drivers/spi/stmicro.c index fb24b27..6625764 100644 --- a/src/drivers/spi/stmicro.c +++ b/src/drivers/spi/stmicro.c @@ -351,7 +351,6 @@ static const struct spi_flash_ops spi_flash_ops = { .write = stmicro_write, .erase = spi_flash_cmd_erase, - .read = spi_flash_cmd_read_fast, };
int spi_flash_probe_stmicro(const struct spi_slave *spi, u8 *idcode, diff --git a/src/drivers/spi/winbond.c b/src/drivers/spi/winbond.c index 11a5187..d0ef3cd 100644 --- a/src/drivers/spi/winbond.c +++ b/src/drivers/spi/winbond.c @@ -646,11 +646,6 @@ .write = winbond_write, .erase = spi_flash_cmd_erase, .status = spi_flash_cmd_status, -#if CONFIG(SPI_FLASH_NO_FAST_READ) - .read = spi_flash_cmd_read_slow, -#else - .read = spi_flash_cmd_read_fast, -#endif .get_write_protection = winbond_get_write_protection, .set_write_protection = winbond_set_write_protection, };