| Message ID | 1377686689-30828-3-git-send-email-Sudeep.KarkadaNagesha@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Aug 28, 2013 at 11:44:46AM +0100, Sudeep KarkadaNagesha wrote: > From: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com> > > This patch adds support for configuring the event stream frequency > and enabling it. > > It also adds the hwcaps definitions to the user to detect this event > stream feature. > > Cc: Russell King <linux@arm.linux.org.uk> > Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> > Cc: Will Deacon <will.deacon@arm.com> > Cc: Catalin Marinas <catalin.marinas@arm.com> > Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com> > --- > arch/arm/include/asm/arch_timer.h | 33 ++++++++++++++++++++++++++++----- > arch/arm/include/uapi/asm/hwcap.h | 1 + > arch/arm/kernel/setup.c | 1 + > 3 files changed, 30 insertions(+), 5 deletions(-) > > diff --git a/arch/arm/include/asm/arch_timer.h b/arch/arm/include/asm/arch_timer.h > index 1a3e967..4e38609 100644 > --- a/arch/arm/include/asm/arch_timer.h > +++ b/arch/arm/include/asm/arch_timer.h > @@ -89,22 +89,45 @@ static inline u64 arch_counter_get_cntvct(void) > return cval; > } > > -static inline void arch_counter_set_user_access(void) > +static inline u32 arch_timer_get_cntkctl(void) > { > u32 cntkctl; > - > asm volatile("mrc p15, 0, %0, c14, c1, 0" : "=r" (cntkctl)); > + return cntkctl; > +} > + > +static inline void arch_timer_set_cntkctl(u32 cntkctl) > +{ > + asm volatile("mcr p15, 0, %0, c14, c1, 0" : : "r" (cntkctl)); > +} > + > +static inline void arch_counter_set_user_access(void) > +{ > + u32 cntkctl = arch_timer_get_cntkctl(); > > /* Disable user access to both physical/virtual counters/timers */ > - /* 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_VCT_ACCESS_EN > | ARCH_TIMER_USR_PCT_ACCESS_EN); > + arch_timer_set_cntkctl(cntkctl); > +} You can keep the ARCH_TIMER_VIRT_EVT_EN clearing here, especially if we drop the bool enable argument to arch_timer_evtstrm_config(). You can add the same clearing to arm64 in one of the latter patches.
diff --git a/arch/arm/include/asm/arch_timer.h b/arch/arm/include/asm/arch_timer.h index 1a3e967..4e38609 100644 --- a/arch/arm/include/asm/arch_timer.h +++ b/arch/arm/include/asm/arch_timer.h @@ -89,22 +89,45 @@ static inline u64 arch_counter_get_cntvct(void) return cval; } -static inline void arch_counter_set_user_access(void) +static inline u32 arch_timer_get_cntkctl(void) { u32 cntkctl; - asm volatile("mrc p15, 0, %0, c14, c1, 0" : "=r" (cntkctl)); + return cntkctl; +} + +static inline void arch_timer_set_cntkctl(u32 cntkctl) +{ + asm volatile("mcr p15, 0, %0, c14, c1, 0" : : "r" (cntkctl)); +} + +static inline void arch_counter_set_user_access(void) +{ + u32 cntkctl = arch_timer_get_cntkctl(); /* Disable user access to both physical/virtual counters/timers */ - /* 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_VCT_ACCESS_EN | ARCH_TIMER_USR_PCT_ACCESS_EN); + arch_timer_set_cntkctl(cntkctl); +} - asm volatile("mcr p15, 0, %0, c14, c1, 0" : : "r" (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; + elf_hwcap |= HWCAP_EVTSTRM; + } else { + cntkctl &= ~ARCH_TIMER_VIRT_EVT_EN; /* disable event stream */ + } + arch_timer_set_cntkctl(cntkctl); } + #endif #endif diff --git a/arch/arm/include/uapi/asm/hwcap.h b/arch/arm/include/uapi/asm/hwcap.h index 6d34d08..7dcc10d 100644 --- a/arch/arm/include/uapi/asm/hwcap.h +++ b/arch/arm/include/uapi/asm/hwcap.h @@ -26,5 +26,6 @@ #define HWCAP_VFPD32 (1 << 19) /* set if VFP has 32 regs (not 16) */ #define HWCAP_IDIV (HWCAP_IDIVA | HWCAP_IDIVT) #define HWCAP_LPAE (1 << 20) +#define HWCAP_EVTSTRM (1 << 21) #endif /* _UAPI__ASMARM_HWCAP_H */ diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index afc2489..305ffc9 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -975,6 +975,7 @@ static const char *hwcap_str[] = { "idivt", "vfpd32", "lpae", + "evtstrm", NULL };