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3 commits

Author SHA1 Message Date
Manivannan Sadhasivam
a817ef3fea scsi: ufs: ufs-qcom: Fix the Qcom register name for offset 0xD0
[ Upstream commit 7959587f3284bf163e4f1baff3c6fa71fc6a55b1 ]

On newer UFS revisions, the register at offset 0xD0 is called,
REG_UFS_PARAM0. Since the existing register, RETRY_TIMER_REG is not used
anywhere, it is safe to use the new name.

Reviewed-by: Andrew Halaney <ahalaney@redhat.com>
Reviewed-by: Asutosh Das <quic_asutoshd@quicinc.com>
Tested-by: Andrew Halaney <ahalaney@redhat.com> # Qdrive3/sa8540p-ride
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Stable-dep-of: 823150ecf04f ("scsi: ufs: qcom: Perform read back after writing unipro mode")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:26:53 +01:00
Andrew Halaney
d0901a4686 scsi: ufs: qcom: Perform read back after writing reset bit
[ Upstream commit c4d28e06b0c94636f6e35d003fa9ebac0a94e1ae ]

Currently, the reset bit for the UFS provided reset controller (used by its
phy) is written to, and then a mb() happens to try and ensure that hit the
device. Immediately afterwards a usleep_range() occurs.

mb() ensures that the write completes, but completion doesn't mean that it
isn't stored in a buffer somewhere. The recommendation for ensuring this
bit has taken effect on the device is to perform a read back to force it to
make it all the way to the device. This is documented in device-io.rst and
a talk by Will Deacon on this can be seen over here:

    https://youtu.be/i6DayghhA8Q?si=MiyxB5cKJXSaoc01&t=1678

Let's do that to ensure the bit hits the device. By doing so and
guaranteeing the ordering against the immediately following usleep_range(),
the mb() can safely be removed.

Fixes: 81c0fc51b7a7 ("ufs-qcom: add support for Qualcomm Technologies Inc platforms")
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Can Guo <quic_cang@quicinc.com>
Signed-off-by: Andrew Halaney <ahalaney@redhat.com>
Link: https://lore.kernel.org/r/20240329-ufs-reset-ensure-effect-before-delay-v5-1-181252004586@redhat.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:26:53 +01:00
Gabriel2392
7ed7ee9edf Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00