6.1-stable review patch. If anyone has any objections, please let me know.
------------------
From: Bjorn Andersson quic_bjorande@quicinc.com
commit 2a93c6cbd5a703d44c414a3c3945a87ce11430ba upstream.
Commit 'e3e56c050ab6 ("soc: qcom: rpmhpd: Make power_on actually enable the domain")' aimed to make sure that a power-domain that is being enabled without any particular performance-state requested will at least turn the rail on, to avoid filling DeviceTree with otherwise unnecessary required-opps properties.
But in the event that aggregation happens on a disabled power-domain, with an enabled peer without performance-state, both the local and peer corner are 0. The peer's enabled_corner is not considered, with the result that the underlying (shared) resource is disabled.
One case where this can be observed is when the display stack keeps mmcx enabled (but without a particular performance-state vote) in order to access registers and sync_state happens in the rpmhpd driver. As mmcx_ao is flushed the state of the peer (mmcx) is not considered and mmcx_ao ends up turning off "mmcx.lvl" underneath mmcx. This has been observed several times, but has been painted over in DeviceTree by adding an explicit vote for the lowest non-disabled performance-state.
Fixes: e3e56c050ab6 ("soc: qcom: rpmhpd: Make power_on actually enable the domain") Reported-by: Johan Hovold johan@kernel.org Closes: https://lore.kernel.org/linux-arm-msm/ZdMwZa98L23mu3u6@hovoldconsulting.com/ Cc: stable@vger.kernel.org Signed-off-by: Bjorn Andersson quic_bjorande@quicinc.com Reviewed-by: Konrad Dybcio konrad.dybcio@linaro.org Reviewed-by: Dmitry Baryshkov dmitry.baryshkov@linaro.org Tested-by: Dmitry Baryshkov dmitry.baryshkov@linaro.org Reviewed-by: Abhinav Kumar quic_abhinavk@quicinc.com Reviewed-by: Stephen Boyd swboyd@chromium.org Tested-by: Johan Hovold johan+linaro@kernel.org Link: https://lore.kernel.org/r/20240226-rpmhpd-enable-corner-fix-v1-1-68c004cec48... Signed-off-by: Ulf Hansson ulf.hansson@linaro.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/soc/qcom/rpmhpd.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)
--- a/drivers/soc/qcom/rpmhpd.c +++ b/drivers/soc/qcom/rpmhpd.c @@ -492,12 +492,15 @@ static int rpmhpd_aggregate_corner(struc unsigned int active_corner, sleep_corner; unsigned int this_active_corner = 0, this_sleep_corner = 0; unsigned int peer_active_corner = 0, peer_sleep_corner = 0; + unsigned int peer_enabled_corner;
to_active_sleep(pd, corner, &this_active_corner, &this_sleep_corner);
- if (peer && peer->enabled) - to_active_sleep(peer, peer->corner, &peer_active_corner, + if (peer && peer->enabled) { + peer_enabled_corner = max(peer->corner, peer->enable_corner); + to_active_sleep(peer, peer_enabled_corner, &peer_active_corner, &peer_sleep_corner); + }
active_corner = max(this_active_corner, peer_active_corner);