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| author | Xinwei Kong <kong.kongxinwei@hisilicon.com> | 2020-01-03 10:52:10 +0800 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2020-01-06 20:49:03 +0000 |
| commit | bfda044533b213985bc62bd7ca96f2b984d21b80 (patch) | |
| tree | 9ac27f2aec9f611e097d5d3b9d42b546a2f558a5 | |
| parent | 09b6636cea4f8e419d7cca4155e8695e462535a6 (diff) | |
| download | linux-bfda044533b213985bc62bd7ca96f2b984d21b80.tar.gz | |
spi: dw: use "smp_mb()" to avoid sending spi data error
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>
| -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 c547ae38ed69..310492e21b33 100644 --- a/drivers/spi/spi-dw.c +++ b/drivers/spi/spi-dw.c @@ -297,6 +297,9 @@ static int dw_spi_transfer_one(struct spi_controller *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 */ |