diff options
| author | Rafał Miłecki <rafal@milecki.pl> | 2018-10-11 09:42:17 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-11-13 11:08:15 -0800 |
| commit | 97baa6b21b2997d727779ae3a1780968ca956baa (patch) | |
| tree | 642ffa5cf0569cc689bb3a99b111cb41f8554147 | |
| parent | 9251a21bb4f764a89a3bf9a902d75cf792eb65eb (diff) | |
spi: bcm-qspi: switch back to reading flash using smaller chunks
commit 940ec770c295682993d1cccce3081fd7c74fece8 upstream.
Fixing/optimizing bcm_qspi_bspi_read() performance introduced two
changes:
1) It added a loop to read all requested data using multiple BSPI ops.
2) It bumped max size of a single BSPI block request from 256 to 512 B.
The later change resulted in occasional BSPI timeouts causing a
regression.
For some unknown reason hardware doesn't always handle reads as expected
when using 512 B chunks. In such cases it may happen that BSPI returns
amount of requested bytes without the last 1-3 ones. It provides the
remaining bytes later but doesn't raise an interrupt until another LR
start.
Switching back to 256 B reads fixes that problem and regression.
Fixes: 345309fa7c0c ("spi: bcm-qspi: Fix bcm_qspi_bspi_read() performance")
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/spi/spi-bcm-qspi.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/spi/spi-bcm-qspi.c b/drivers/spi/spi-bcm-qspi.c index 8612525fa4e3..8992acda4f1f 100644 --- a/drivers/spi/spi-bcm-qspi.c +++ b/drivers/spi/spi-bcm-qspi.c @@ -89,7 +89,7 @@ #define BSPI_BPP_MODE_SELECT_MASK BIT(8) #define BSPI_BPP_ADDR_SELECT_MASK BIT(16) -#define BSPI_READ_LENGTH 512 +#define BSPI_READ_LENGTH 256 /* MSPI register offsets */ #define MSPI_SPCR0_LSB 0x000 |