| Message ID | 1377018526-9832-1-git-send-email-Sudeep.KarkadaNagesha@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Sudeep, On Tue, Aug 20, 2013 at 06:08:46PM +0100, Sudeep KarkadaNagesha wrote: > From: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com> > > This patch configures the event stream frequency and enables 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> > Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> > Signed-off-by: Will Deacon <will.deacon@arm.com> > [sudeep: moving ARM/ARM64 changes into separate patches] > Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com> > --- > arch/arm64/include/asm/arch_timer.h | 15 +++++++++++++-- > arch/arm64/include/asm/hwcap.h | 7 ++++++- > arch/arm64/include/uapi/asm/hwcap.h | 1 + > arch/arm64/kernel/setup.c | 6 ++++++ > 4 files changed, 26 insertions(+), 3 deletions(-) > > Hi Will, > > This is modified version enabling timer event stream hwcap compat dynamically. > Let me know if this looks fine. Looks pretty good to me, one minor comment: > diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c > index add6ea6..91af65a 100644 > --- a/arch/arm64/kernel/setup.c > +++ b/arch/arm64/kernel/setup.c > @@ -60,6 +60,11 @@ 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 = 0; > +EXPORT_SYMBOL_GPL(compat_dyn_elf_hwcap); > +#endif Given that the arch timer is the only user of this at the moment, and cannot be built as a module, I don't think we should bother exporting the symbol until it's actually required. Will
diff --git a/arch/arm64/include/asm/arch_timer.h b/arch/arm64/include/asm/arch_timer.h index 69f5c8e..90f9d1a 100644 --- a/arch/arm64/include/asm/arch_timer.h +++ b/arch/arm64/include/asm/arch_timer.h @@ -106,14 +106,25 @@ static inline void arch_counter_set_user_access(int divider) /* 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_EVT_TRIGGER_MASK | ARCH_TIMER_USR_PCT_ACCESS_EN); - /* Enable user access to the virtual counter. */ - cntkctl |= ARCH_TIMER_USR_VCT_ACCESS_EN; + /* Enable event stream and user access to the virtual counter */ + cntkctl |= (divider << ARCH_TIMER_EVT_TRIGGER_SHIFT) + | ARCH_TIMER_VIRT_EVT_EN + | ARCH_TIMER_USR_VCT_ACCESS_EN; asm volatile("msr cntkctl_el1, %0" : : "r" (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) { u64 cval; 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..91af65a 100644 --- a/arch/arm64/kernel/setup.c +++ b/arch/arm64/kernel/setup.c @@ -60,6 +60,11 @@ 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 = 0; +EXPORT_SYMBOL_GPL(compat_dyn_elf_hwcap); +#endif + static const char *cpu_name; static const char *machine_name; phys_addr_t __fdt_pointer __initdata; @@ -309,6 +314,7 @@ subsys_initcall(topology_init); static const char *hwcap_str[] = { "fp", "asimd", + "evtstrm", NULL };