From: Benjamin Bigler benjamin@bigler.one
stable inclusion from stable-v6.6.9 commit a8b655ac35be588df0bec9c56b565bc72a188682 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I8SU2D
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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[ Upstream commit e9b220aeacf109684cce36a94fc24ed37be92b05 ]
If DMA is used, burst length should be set to the bus width of the DMA. Otherwise, the SPI hardware will transmit/receive one word per DMA request. Since this issue affects both transmission and reception, it cannot be detected with a loopback test. Replace magic numbers 512 and 0xfff with MX51_ECSPI_CTRL_MAX_BURST.
Reported-by Stefan Bigler linux@bigler.io
Signed-off-by: Benjamin Bigler benjamin@bigler.one Fixes: 15a6af94a277 ("spi: Increase imx51 ecspi burst length based on transfer length") Link: https://lore.kernel.org/r/8a415902c751cdbb4b20ce76569216ed@mail.infomaniak.c... Link: https://lore.kernel.org/r/20231209222338.5564-1-benjamin@bigler.one Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- drivers/spi/spi-imx.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-)
diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c index 498e35c8db2c..272bc871a848 100644 --- a/drivers/spi/spi-imx.c +++ b/drivers/spi/spi-imx.c @@ -659,11 +659,18 @@ static int mx51_ecspi_prepare_transfer(struct spi_imx_data *spi_imx, ctrl |= (spi_imx->target_burst * 8 - 1) << MX51_ECSPI_CTRL_BL_OFFSET; else { - if (spi_imx->count >= 512) - ctrl |= 0xFFF << MX51_ECSPI_CTRL_BL_OFFSET; - else - ctrl |= (spi_imx->count * spi_imx->bits_per_word - 1) + if (spi_imx->usedma) { + ctrl |= (spi_imx->bits_per_word * + spi_imx_bytes_per_word(spi_imx->bits_per_word) - 1) << MX51_ECSPI_CTRL_BL_OFFSET; + } else { + if (spi_imx->count >= MX51_ECSPI_CTRL_MAX_BURST) + ctrl |= (MX51_ECSPI_CTRL_MAX_BURST - 1) + << MX51_ECSPI_CTRL_BL_OFFSET; + else + ctrl |= (spi_imx->count * spi_imx->bits_per_word - 1) + << MX51_ECSPI_CTRL_BL_OFFSET; + } }
/* set clock speed */