[PATCH v4 3/5] ARM64: arch_timer: add support to configure and enable event stream
From: Sudeep KarkadaNagesha <hidden>
Date: 2013-08-23 16:20:29
Also in:
lkml
Subsystem:
arm architected timer driver, arm64 port (aarch64 architecture), the rest · Maintainers:
Mark Rutland, Marc Zyngier, Catalin Marinas, Will Deacon, Linus Torvalds
From: Sudeep KarkadaNagesha <redacted> This patch adds support for configure 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: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <redacted> Cc: Lorenzo Pieralisi <redacted> Signed-off-by: Sudeep KarkadaNagesha <redacted> --- arch/arm64/include/asm/arch_timer.h | 40 +++++++++++++++++++++++++++++++++---- arch/arm64/include/asm/hwcap.h | 7 ++++++- arch/arm64/include/uapi/asm/hwcap.h | 1 + arch/arm64/kernel/setup.c | 5 +++++ 4 files changed, 48 insertions(+), 5 deletions(-)
diff --git a/arch/arm64/include/asm/arch_timer.h b/arch/arm64/include/asm/arch_timer.h
index 00b09d0..0f57158 100644
--- a/arch/arm64/include/asm/arch_timer.h
+++ b/arch/arm64/include/asm/arch_timer.h@@ -97,21 +97,53 @@ 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. */ cntkctl &= ~(ARCH_TIMER_USR_PT_ACCESS_EN | ARCH_TIMER_USR_VT_ACCESS_EN | ARCH_TIMER_USR_PCT_ACCESS_EN); - /* Enable user access to the virtual counter. */ + /* 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_config(bool enable, int divider) +{ + u32 cntkctl = arch_timer_get_cntkctl(); + if (enable) { + 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; + } else { + cntkctl &= ~ARCH_TIMER_VIRT_EVT_EN; /* disable event stream */ + } + arch_timer_set_cntkctl(cntkctl); +} + +static inline void arch_timer_set_hwcap_evtstrm(void) +{ + elf_hwcap |= HWCAP_EVTSTRM; +#ifdef CONFIG_COMPAT + compat_dyn_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..022d771 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 +38,15 @@ * instruction set this cpu supports. */ #define ELF_HWCAP (elf_hwcap) +#ifdef CONFIG_COMPAT #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) + COMPAT_HWCAP_NEON|COMPAT_HWCAP_IDIV|\ + compat_dyn_elf_hwcap) +extern unsigned int compat_dyn_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..50aaca814 100644
--- a/arch/arm64/kernel/setup.c
+++ b/arch/arm64/kernel/setup.c@@ -60,6 +60,10 @@ EXPORT_SYMBOL(processor_id); unsigned int elf_hwcap __read_mostly; EXPORT_SYMBOL_GPL(elf_hwcap); +#ifdef CONFIG_COMPAT +unsigned int compat_dyn_elf_hwcap __read_mostly; +#endif + static const char *cpu_name; static const char *machine_name; phys_addr_t __fdt_pointer __initdata;
@@ -309,6 +313,7 @@ subsys_initcall(topology_init); static const char *hwcap_str[] = { "fp", "asimd", + "evtstrm", NULL };
--
1.8.1.2