From: Sudeep KarkadaNagesha <sudeep.karkadanage...@arm.com>
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.pieral...@arm.com>
Cc: Will Deacon <will.dea...@arm.com>
Cc: Catalin Marinas <catalin.mari...@arm.com>
Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanage...@arm.com>
---
arch/arm64/include/asm/arch_timer.h | 32 +++++++++++++++++++++++++++++---
arch/arm64/include/asm/hwcap.h | 11 ++++++-----
arch/arm64/include/uapi/asm/hwcap.h | 1 +
arch/arm64/kernel/setup.c | 11 +++++++++++
4 files changed, 47 insertions(+), 8 deletions(-)
diff --git a/arch/arm64/include/asm/arch_timer.h
b/arch/arm64/include/asm/arch_timer.h
index fa4af76..3bca364 100644
--- a/arch/arm64/include/asm/arch_timer.h
+++ b/arch/arm64/include/asm/arch_timer.h
@@ -97,21 +97,47 @@ 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)
diff --git a/arch/arm64/include/asm/hwcap.h b/arch/arm64/include/asm/hwcap.h
index 6d4482f..3a48433 100644
--- a/arch/arm64/include/asm/hwcap.h
+++ b/arch/arm64/include/asm/hwcap.h
@@ -30,6 +30,7 @@
#define COMPAT_HWCAP_IDIVA (1 << 17)
#define COMPAT_HWCAP_IDIVT (1 << 18)
#define COMPAT_HWCAP_IDIV (COMPAT_HWCAP_IDIVA|COMPAT_HWCAP_IDIVT)
+#define COMPAT_HWCAP_EVTSTRM (1 << 21)
#ifndef __ASSEMBLY__
/*
@@ -37,11 +38,11 @@
* instruction set this cpu supports.
*/
#define ELF_HWCAP (elf_hwcap)
-#define COMPAT_ELF_HWCAP (COMPAT_HWCAP_HALF|COMPAT_HWCAP_THUMB|\
- COMPAT_HWCAP_FAST_MULT|COMPAT_HWCAP_EDSP|\
- COMPAT_HWCAP_TLS|COMPAT_HWCAP_VFP|\
- COMPAT_HWCAP_VFPv3|COMPAT_HWCAP_VFPv4|\
- COMPAT_HWCAP_NEON|COMPAT_HWCAP_IDIV)
+
+#ifdef CONFIG_COMPAT
+#define COMPAT_ELF_HWCAP (compat_elf_hwcap)
+extern unsigned int compat_elf_hwcap;
+#endif
extern unsigned int elf_hwcap;
#endif
diff --git a/arch/arm64/include/uapi/asm/hwcap.h
b/arch/arm64/include/uapi/asm/hwcap.h
index eea4975..9b12476 100644
--- a/arch/arm64/include/uapi/asm/hwcap.h
+++ b/arch/arm64/include/uapi/asm/hwcap.h
@@ -21,6 +21,7 @@
*/
#define HWCAP_FP (1 << 0)
#define HWCAP_ASIMD (1 << 1)
+#define HWCAP_EVTSTRM (1 << 2)
#endif /* _UAPI__ASM_HWCAP_H */
diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
index add6ea6..57cb006 100644
--- a/arch/arm64/kernel/setup.c
+++ b/arch/arm64/kernel/setup.c
@@ -60,6 +60,16 @@ EXPORT_SYMBOL(processor_id);
unsigned int elf_hwcap __read_mostly;
EXPORT_SYMBOL_GPL(elf_hwcap);
+#ifdef CONFIG_COMPAT
+#define COMPAT_ELF_HWCAP_DEFAULT \
+ (COMPAT_HWCAP_HALF|COMPAT_HWCAP_THUMB|\
+ COMPAT_HWCAP_FAST_MULT|COMPAT_HWCAP_EDSP|\
+ COMPAT_HWCAP_TLS|COMPAT_HWCAP_VFP|\
+ COMPAT_HWCAP_VFPv3|COMPAT_HWCAP_VFPv4|\
+ COMPAT_HWCAP_NEON|COMPAT_HWCAP_IDIV)
+unsigned int compat_elf_hwcap __read_mostly = COMPAT_ELF_HWCAP_DEFAULT;
+#endif
+
static const char *cpu_name;
static const char *machine_name;
phys_addr_t __fdt_pointer __initdata;
@@ -309,6 +319,7 @@ subsys_initcall(topology_init);
static const char *hwcap_str[] = {
"fp",
"asimd",
+ "evtstrm",
NULL
};
--
1.8.1.2
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