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

[~andy/linux] / arch / arm64 / include / asm / arch_timer.h

diff --git a/arch/arm64/include/asm/arch_timer.h b/arch/arm64/include/asm/arch_timer.h
index c9f1d2816c2bb9086be3b2e001c5d81921a076bf..9400596a0f3972a91a8858da56e9d7097e4b9319 100644 (file)
--- a/arch/arm64/include/asm/arch_timer.h
+++ b/arch/arm64/include/asm/arch_timer.h
@@ -92,19 +92,49 @@ 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;
-
-       /* Disable user access to the timers and the physical counter. */
        asm volatile("mrs       %0, cntkctl_el1" : "=r" (cntkctl));
-       cntkctl &= ~((3 << 8) | (1 << 0));
+       return cntkctl;
+}
 
-       /* Enable user access to the virtual counter and frequency. */
-       cntkctl |= (1 << 1);
+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;
+
+       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)
 {
        u64 cval;