diff options
author | Brian Norris <briannorris@chromium.org> | 2017-04-04 19:32:05 +0000 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-04-12 12:41:16 +0200 |
commit | 26cbe162df3d0282e5108711663b8dcdafb1ad33 (patch) | |
tree | c8dd2fc66bb25fc646f349c6cae47b1b18829e28 /Documentation | |
parent | d2f1000c3ae3ce285d99dae444f85baa53c1dfe6 (diff) |
clocksource/drivers/arm_arch_timer: Don't assume clock runs in suspend
[ Upstream commit d8ec7595a013237f82d965dcf981571aeb41855b ]
The ARM specifies that the system counter "must be implemented in an
always-on power domain," and so we try to use the counter as a source of
timekeeping across suspend/resume. Unfortunately, some SoCs (e.g.,
Rockchip's RK3399) do not keep the counter ticking properly when
switched from their high-power clock to the lower-power clock used in
system suspend. Support this quirk by adding a new device tree property.
Signed-off-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/devicetree/bindings/arm/arch_timer.txt | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/arm/arch_timer.txt b/Documentation/devicetree/bindings/arm/arch_timer.txt index ef5fbe9a77c7..ad440a2b8051 100644 --- a/Documentation/devicetree/bindings/arm/arch_timer.txt +++ b/Documentation/devicetree/bindings/arm/arch_timer.txt @@ -38,6 +38,11 @@ to deliver its interrupts via SPIs. architecturally-defined reset values. Only supported for 32-bit systems which follow the ARMv7 architected reset values. +- arm,no-tick-in-suspend : The main counter does not tick when the system is in + low-power system suspend on some SoCs. This behavior does not match the + Architecture Reference Manual's specification that the system counter "must + be implemented in an always-on power domain." + Example: |