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H A Dgcc-sm8550.ca5e871d2 Mon Aug 19 18:36:26 CDT 2024 Stephen Boyd <swboyd@chromium.org> clk: qcom: gcc-sm8550: Don't use parking clk_ops for QUPs

[ Upstream commit d10eeb75168b84ed9559c58efe2756c2e0bc052a ]

The QUPs aren't shared in a way that requires parking the RCG at an
always on parent in case some other entity turns on the clk. The
hardware is capable of setting a new frequency itself with the DFS mode,
so parking is unnecessary. Furthermore, there aren't any GDSCs for these
devices, so there isn't a possibility of the GDSC turning on the clks
for housekeeping purposes.

This wasn't a problem to mark these clks shared until we started parking
shared RCGs at clk registration time in commit 01a0a6cc8cfd ("clk: qcom:
Park shared RCGs upon registration"). Parking at init is actually
harmful to the UART when earlycon is used. If the device is pumping out
data while the frequency changes you'll see garbage on the serial
console until the driver can probe and actually set a proper frequency.

Revert the QUP part of commit 929c75d57566 ("clk: qcom: gcc-sm8550: Mark
RCGs shared where applicable") so that the QUPs don't get parked during
clk registration and break UART operations.

Fixes: 01a0a6cc8cfd ("clk: qcom: Park shared RCGs upon registration")
Fixes: 929c75d57566 ("clk: qcom: gcc-sm8550: Mark RCGs shared where applicable")
Cc: Konrad Dybcio <konradybcio@kernel.org>
Cc: Bjorn Andersson <andersson@kernel.org>
Cc: Taniya Das <quic_tdas@quicinc.com>
Reported-by: Amit Pundir <amit.pundir@linaro.org>
Closes: https://lore.kernel.org/CAMi1Hd1KQBE4kKUdAn8E5FV+BiKzuv+8FoyWQrrTHPDoYTuhgA@mail.gmail.com
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20240819233628.2074654-2-swboyd@chromium.org
Tested-by: Amit Pundir <amit.pundir@linaro.org>
Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on SM8550-QRD
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>