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clocksource: arch_timer: Disable user access to the physical counter

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Disable user access to physical counter. This reverts
commit 63cb2598d5ba ("clocksource: arch_timer: Enable
user access to the physical counter").

This could potentially break the userspace applications
using physical counters; but all those usages should
move to using virtual counter, to get the timing
information.

Change-Id: I653816a93515507a400ff23dbaa4442bf614a79b
Signed-off-by: Neeraj Upadhyay <neeraju@codeaurora.org>
This commit is contained in:
Neeraj Upadhyay 2018-01-05 11:03:42 +05:30
parent 3851c63407
commit a6a585a209
1 changed files with 5 additions and 4 deletions
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9
drivers/clocksource/arm_arch_timer.c
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@ -326,13 +326,14 @@ static void arch_counter_set_user_access(void)
{
u32 cntkctl = arch_timer_get_cntkctl();
/* Disable user access to the timers */
/* Disable user access to the timers and the physical counter */
/* Also disable virtual event stream */
cntkctl &= ~(ARCH_TIMER_USR_PT_ACCESS_EN
| ARCH_TIMER_VIRT_EVT_EN);
| ARCH_TIMER_VIRT_EVT_EN
| ARCH_TIMER_USR_PCT_ACCESS_EN);
/* Enable user access to the virtual and physical counters */
cntkctl |= ARCH_TIMER_USR_PCT_ACCESS_EN | ARCH_TIMER_USR_VT_ACCESS_EN;
/* Enable user access to the virtual counter */
cntkctl |= ARCH_TIMER_USR_VT_ACCESS_EN;
if (IS_ENABLED(CONFIG_ARM_ARCH_TIMER_VCT_ACCESS))
cntkctl |= ARCH_TIMER_USR_VCT_ACCESS_EN;