[PATCH v1 0/2] NVIDIA Tegra I2C synchronization correction

From: Dmitry Osipenko
Date: Thu Mar 19 2020 - 16:12:38 EST


Hello,

Recently I found a way to reliably reproduce I2C timeouts that happen due
to improper synchronizations made by the I2C driver. It's quite easy to
reproduce the problem when memory is running on a lower freq + there is
some memory activity + CPU could get busy for a significant time. This
is the case when KASAN is enabled and CPU is busy while accessing FS via
NFS. This small series addresses the found problems.

Please note that the "Synchronize DMA before termination" patch implicitly
depends on the "dmaengine: tegra-apb: Improve DMA synchronization" patch,
which is sent separately, otherwise DMA synchronization won't happen.

Dmitry Osipenko (2):
i2c: tegra: Better handle case where CPU0 is busy for a long time
i2c: tegra: Synchronize DMA before termination

drivers/i2c/busses/i2c-tegra.c | 27 ++++++++++++++++++++-------
1 file changed, 20 insertions(+), 7 deletions(-)

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2.25.1