[05/18] arm64: kill change_cpacr()

Message ID 20180514094640.27569-6-mark.rutland@arm.com
State Superseded
Headers show
Series
  • arm64: invoke syscalls with pt_regs
Related show

Commit Message

Mark Rutland May 14, 2018, 9:46 a.m.
Now that we have sysreg_clear_set(), we can use this instead of
change_cpacr().

Note that the order of the set and clear arguments differs between
change_cpacr() and sysreg_clear_set(), so these are flipped as part of
the conversion. Also, sve_user_enable() redundantly clears
CPACR_EL1_ZEN_EL0EN before setting it; this is removed for clarity.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Martin <dave.martin@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
---
 arch/arm64/kernel/fpsimd.c | 13 ++-----------
 1 file changed, 2 insertions(+), 11 deletions(-)

-- 
2.11.0

Comments

Dave Martin May 14, 2018, 10:06 a.m. | #1
On Mon, May 14, 2018 at 10:46:27AM +0100, Mark Rutland wrote:
> Now that we have sysreg_clear_set(), we can use this instead of

> change_cpacr().

> 

> Note that the order of the set and clear arguments differs between

> change_cpacr() and sysreg_clear_set(), so these are flipped as part of

> the conversion. Also, sve_user_enable() redundantly clears

> CPACR_EL1_ZEN_EL0EN before setting it; this is removed for clarity.

> 

> Signed-off-by: Mark Rutland <mark.rutland@arm.com>

> Cc: Catalin Marinas <catalin.marinas@arm.com>

> Cc: Dave Martin <dave.martin@arm.com>

> Cc: James Morse <james.morse@arm.com>

> Cc: Will Deacon <will.deacon@arm.com>


Looks right to me.

Reviewed-by: Dave Martin <Dave.Martin@arm.com>


> ---

>  arch/arm64/kernel/fpsimd.c | 13 ++-----------

>  1 file changed, 2 insertions(+), 11 deletions(-)

> 

> diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c

> index 87a35364e750..088940387a4d 100644

> --- a/arch/arm64/kernel/fpsimd.c

> +++ b/arch/arm64/kernel/fpsimd.c

> @@ -172,23 +172,14 @@ static void *sve_pffr(struct task_struct *task)

>  		sve_ffr_offset(task->thread.sve_vl);

>  }

>  

> -static void change_cpacr(u64 val, u64 mask)

> -{

> -	u64 cpacr = read_sysreg(CPACR_EL1);

> -	u64 new = (cpacr & ~mask) | val;

> -

> -	if (new != cpacr)

> -		write_sysreg(new, CPACR_EL1);

> -}

> -

>  static void sve_user_disable(void)

>  {

> -	change_cpacr(0, CPACR_EL1_ZEN_EL0EN);

> +	sysreg_clear_set(cpacr_el1, CPACR_EL1_ZEN_EL0EN, 0);

>  }

>  

>  static void sve_user_enable(void)

>  {

> -	change_cpacr(CPACR_EL1_ZEN_EL0EN, CPACR_EL1_ZEN_EL0EN);

> +	sysreg_clear_set(cpacr_el1, 0, CPACR_EL1_ZEN_EL0EN);

>  }

>  

>  /*

> -- 

> 2.11.0

> 

> 

> _______________________________________________

> linux-arm-kernel mailing list

> linux-arm-kernel@lists.infradead.org

> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Patch

diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c
index 87a35364e750..088940387a4d 100644
--- a/arch/arm64/kernel/fpsimd.c
+++ b/arch/arm64/kernel/fpsimd.c
@@ -172,23 +172,14 @@  static void *sve_pffr(struct task_struct *task)
 		sve_ffr_offset(task->thread.sve_vl);
 }
 
-static void change_cpacr(u64 val, u64 mask)
-{
-	u64 cpacr = read_sysreg(CPACR_EL1);
-	u64 new = (cpacr & ~mask) | val;
-
-	if (new != cpacr)
-		write_sysreg(new, CPACR_EL1);
-}
-
 static void sve_user_disable(void)
 {
-	change_cpacr(0, CPACR_EL1_ZEN_EL0EN);
+	sysreg_clear_set(cpacr_el1, CPACR_EL1_ZEN_EL0EN, 0);
 }
 
 static void sve_user_enable(void)
 {
-	change_cpacr(CPACR_EL1_ZEN_EL0EN, CPACR_EL1_ZEN_EL0EN);
+	sysreg_clear_set(cpacr_el1, 0, CPACR_EL1_ZEN_EL0EN);
 }
 
 /*