ARM64: arch_timer: add support to configure and enable event stream

This patch adds support for configuring the event stream frequency
and enabling it.

It also adds the hwcaps as well as compat-specific definitions to
the user to detect this event stream feature.

Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
This commit is contained in:
Sudeep KarkadaNagesha
2013-08-13 15:57:53 +01:00
parent e9faebc66e
commit 46efe547ac
4 changed files with 47 additions and 8 deletions

View File

@@ -92,21 +92,47 @@ static inline u32 arch_timer_get_cntfrq(void)
return val;
}
static inline void arch_counter_set_user_access(void)
static inline u32 arch_timer_get_cntkctl(void)
{
u32 cntkctl;
asm volatile("mrs %0, cntkctl_el1" : "=r" (cntkctl));
return cntkctl;
}
static inline void arch_timer_set_cntkctl(u32 cntkctl)
{
asm volatile("msr cntkctl_el1, %0" : : "r" (cntkctl));
}
static inline void arch_counter_set_user_access(void)
{
u32 cntkctl = arch_timer_get_cntkctl();
/* Disable user access to the timers and the physical counter */
/* Also disable virtual event stream */
cntkctl &= ~(ARCH_TIMER_USR_PT_ACCESS_EN
| ARCH_TIMER_USR_VT_ACCESS_EN
| ARCH_TIMER_VIRT_EVT_EN
| ARCH_TIMER_USR_PCT_ACCESS_EN);
/* Enable user access to the virtual counter */
cntkctl |= ARCH_TIMER_USR_VCT_ACCESS_EN;
asm volatile("msr cntkctl_el1, %0" : : "r" (cntkctl));
arch_timer_set_cntkctl(cntkctl);
}
static inline void arch_timer_evtstrm_enable(int divider)
{
u32 cntkctl = arch_timer_get_cntkctl();
cntkctl &= ~ARCH_TIMER_EVT_TRIGGER_MASK;
/* Set the divider and enable virtual event stream */
cntkctl |= (divider << ARCH_TIMER_EVT_TRIGGER_SHIFT)
| ARCH_TIMER_VIRT_EVT_EN;
arch_timer_set_cntkctl(cntkctl);
elf_hwcap |= HWCAP_EVTSTRM;
#ifdef CONFIG_COMPAT
compat_elf_hwcap |= COMPAT_HWCAP_EVTSTRM;
#endif
}
static inline u64 arch_counter_get_cntvct(void)