diff options
author | Aaron Durbin <adurbin@chromium.org> | 2018-01-29 11:30:17 -0700 |
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committer | Aaron Durbin <adurbin@chromium.org> | 2018-01-30 05:37:47 +0000 |
commit | 1fcc9f3125f88595a89392e9736ebb01e7788842 (patch) | |
tree | 998555b6275b5b22e6e73f14ff2baab99841b32c /src/drivers | |
parent | 3c0d7cfb947d12bdadc5d1898d23d29c93e0ec03 (diff) |
drivers/spi: support cmd opcode deduction for spi_crop_chunk()
spi_crop_chunk() currently supports deducting the command length
when determining maximum payload size in a transaction. Add support
for deducting just the opcode part of the command by replacing
deduct_cmd_len field to generic flags field. The two enums supported
drive the logic within spi_crop_chunk():
SPI_CNTRLR_DEDUCT_CMD_LEN
SPI_CNTRLR_DEDUCT_OPCODE_LEN
All existing users of deduct_cmd_len were converted to using the
flags field.
BUG=b:65485690
Change-Id: I771fba684f0ed76ffdc8573aa10f775070edc691
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://review.coreboot.org/23491
Reviewed-by: Furquan Shaikh <furquan@google.com>
Reviewed-by: Justin TerAvest <teravest@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Diffstat (limited to 'src/drivers')
-rw-r--r-- | src/drivers/spi/spi-generic.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/src/drivers/spi/spi-generic.c b/src/drivers/spi/spi-generic.c index 31a6bc3155..1fcc05d4f3 100644 --- a/src/drivers/spi/spi-generic.c +++ b/src/drivers/spi/spi-generic.c @@ -93,15 +93,24 @@ unsigned int spi_crop_chunk(const struct spi_slave *slave, unsigned int cmd_len, { const struct spi_ctrlr *ctrlr = slave->ctrlr; unsigned int ctrlr_max; + bool deduct_cmd_len; + bool deduct_opcode_len; if (!ctrlr) return 0; + deduct_cmd_len = !!(ctrlr->flags & SPI_CNTRLR_DEDUCT_CMD_LEN); + deduct_opcode_len = !!(ctrlr->flags & SPI_CNTRLR_DEDUCT_OPCODE_LEN); ctrlr_max = ctrlr->max_xfer_size; assert (ctrlr_max != 0); - if (ctrlr->deduct_cmd_len && (ctrlr_max > cmd_len)) + /* Assume opcode is always one byte and deduct it from the cmd_len + as the hardware has a separate register for the opcode. */ + if (deduct_opcode_len) + cmd_len--; + + if (deduct_cmd_len && (ctrlr_max > cmd_len)) ctrlr_max -= cmd_len; return min(ctrlr_max, buf_len); |