diff options
| author | Catalin Marinas <catalin.marinas@arm.com> | 2014-12-10 11:02:09 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-02-05 22:36:09 -0800 |
| commit | b2f21d1b7bc80150f2b7d1fecae5f64c9ead26fa (patch) | |
| tree | a9c02b160fb081396f363789b4cd79cb99b345ce | |
| parent | 793332a4439c431437b26ebcdef7833f46464d06 (diff) | |
clocksource: arch_timer: Only use the virtual counter (CNTVCT) on arm64
commit d6ad36913083d683aad4e02e53580c995f1a6ede upstream.
Commit 0b46b8a718c6 (clocksource: arch_timer: Fix code to use physical
timers when requested) introduces the use of physical counters in the
ARM architected timer driver. However, he arm64 kernel uses CNTVCT in
VDSO. When booting in EL2, the kernel switches to the physical timers to
make things easier for KVM but it continues to use the virtual counter
both in user and kernel. While in such scenario CNTVCT == CNTPCT (since
CNTVOFF is initialised by the kernel to 0), we want to spot firmware
bugs corrupting CNTVOFF early (which would affect CNTVCT).
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Yingjoe Chen <yingjoe.chen@mediatek.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 0b46b8a718c6 ("clocksource: arch_timer: Fix code to use physical
timers when requested")
Cc: Ian Campbell <ijc@hellion.org.uk>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/clocksource/arm_arch_timer.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c index 1fa2af957b18..84b4c8b7fbd1 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -462,7 +462,7 @@ static void __init arch_counter_register(unsigned type) /* Register the CP15 based counter if we have one */ if (type & ARCH_CP15_TIMER) { - if (arch_timer_use_virtual) + if (IS_ENABLED(CONFIG_ARM64) || arch_timer_use_virtual) arch_timer_read_counter = arch_counter_get_cntvct; else arch_timer_read_counter = arch_counter_get_cntpct; |