tree 234b884b2d393fa1e302a6dc5ea69af66c909eb3
parent 345c6f260c89e417de6e7d81f3366bd5079f48a3
author Marek Szyprowski <m.szyprowski@samsung.com> 1600778446 +0200
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1602050407 +0200

clk: samsung: exynos4: mark 'chipid' clock as CLK_IGNORE_UNUSED

[ Upstream commit f3bb0f796f5ffe32f0fbdce5b1b12eb85511158f ]

The ChipID IO region has it's own clock, which is being disabled while
scanning for unused clocks. It turned out that some CPU hotplug, CPU idle
or even SOC firmware code depends on the reads from that area. Fix the
mysterious hang caused by entering deep CPU idle state by ignoring the
'chipid' clock during unused clocks scan, as there are no direct clients
for it which will keep it enabled.

Fixes: e062b571777f ("clk: exynos4: register clocks using common clock framework")
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20200922124046.10496-1-m.szyprowski@samsung.com
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>