diff mbox

[v4,3/5] ARM64: arch_timer: add support to configure and enable event stream

Message ID 1377274749-6196-4-git-send-email-Sudeep.KarkadaNagesha@arm.com (mailing list archive)
State New, archived
Headers show

Commit Message

Sudeep KarkadaNagesha Aug. 23, 2013, 4:19 p.m. UTC 
From: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>

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 <will.deacon@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
---
 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(-)

Comments

Catalin Marinas Aug. 27, 2013, 11:19 a.m. UTC | #1 
On Fri, Aug 23, 2013 at 05:19:07PM +0100, Sudeep KarkadaNagesha wrote:
> 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 */

This change isn't needed here. Just move it to the first patch which
adds the comment.

>  	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

Can we just have a compat_elf_hwcap which is initialised to all the
above and avoid compat_dyn_elf_hwcap?
Sudeep KarkadaNagesha Aug. 27, 2013, 11:31 a.m. UTC | #2 
Hi Catalin,

On 27/08/13 12:19, Catalin Marinas wrote:
> On Fri, Aug 23, 2013 at 05:19:07PM +0100, Sudeep KarkadaNagesha wrote:
>> 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 */
> 
> This change isn't needed here. Just move it to the first patch which
> adds the comment.
> 
It's a mistake, accidentally removed leading '.'
I will remove this.

>>  	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
> 
> Can we just have a compat_elf_hwcap which is initialised to all the
> above and avoid compat_dyn_elf_hwcap?
> 
It was Will's suggestion(https://lkml.org/lkml/2013/8/20/425)
Moreover with config option now it makes more sense to retain it.
It avoids having conditional definition. Let me know your opinion.

Regards,
Sudeep
diff mbox

Patch

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
 };