diff options
| author | Xinwei Kong <kong.kongxinwei@hisilicon.com> | 2020-01-03 10:52:10 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-06-11 09:21:37 +0200 |
| commit | af375aab2eb688b8c02c43159b4378ee95ddda19 (patch) | |
| tree | 4590b800fb346bc0304f15d7795b3d2613f3f57e /drivers/spi/spi-dw.c | |
| parent | 6ddeb501cc5510d2276a9a81a888b9f11ffdca72 (diff) | |
spi: dw: use "smp_mb()" to avoid sending spi data error
[ Upstream commit bfda044533b213985bc62bd7ca96f2b984d21b80 ]
Because of out-of-order execution about some CPU architecture,
In this debug stage we find Completing spi interrupt enable ->
prodrucing TXEI interrupt -> running "interrupt_transfer" function
will prior to set "dw->rx and dws->rx_end" data, so this patch add
memory barrier to enable dw->rx and dw->rx_end to be visible and
solve to send SPI data error.
eg:
it will fix to this following low possibility error in testing environment
which using SPI control to connect TPM Modules
kernel: tpm tpm0: Operation Timed out
kernel: tpm tpm0: tpm_relinquish_locality: : error -1
Signed-off-by: fengsheng <fengsheng5@huawei.com>
Signed-off-by: Xinwei Kong <kong.kongxinwei@hisilicon.com>
Link: https://lore.kernel.org/r/1578019930-55858-1-git-send-email-kong.kongxinwei@hisilicon.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/spi/spi-dw.c')
| -rw-r--r-- | drivers/spi/spi-dw.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/spi/spi-dw.c b/drivers/spi/spi-dw.c index 4edd38d03b93..5688591e9cd3 100644 --- a/drivers/spi/spi-dw.c +++ b/drivers/spi/spi-dw.c @@ -306,6 +306,9 @@ static int dw_spi_transfer_one(struct spi_master *master, dws->len = transfer->len; spin_unlock_irqrestore(&dws->buf_lock, flags); + /* Ensure dw->rx and dw->rx_end are visible */ + smp_mb(); + spi_enable_chip(dws, 0); /* Handle per transfer options for bpw and speed */ |