[ Upstream commit e10b6976f6 ]
HiSilicon UC PMU v2 suffers the erratum 162700402 that the PMU counter
cannot be set due to the lack of clock under power saving mode. This will
lead to error or inaccurate counts. The clock can be enabled by the PMU
global enabling control.
This patch tries to fix this by set the UC PMU enable before set event
period to turn on the clock, and then restore the UC PMU configuration.
The counter register can hold its value without a clock.
Signed-off-by: Junhao He <hejunhao3@huawei.com>
Reviewed-by: Yicong Yang <yangyicong@hisilicon.com>
Link: https://lore.kernel.org/r/20240227125231.53127-1-hejunhao3@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
0662deae8b