diff mbox

[v2,2/9] arm64: kernel: fix style issues in sleep.S

Message ID 1472049366-10922-3-git-send-email-ard.biesheuvel@linaro.org
State Superseded
Headers show

Commit Message

Ard Biesheuvel Aug. 24, 2016, 2:35 p.m. UTC
This fixes a number of style issues in sleep.S. No functional changes are
intended:
- replace absolute literal references with relative references in
  __cpu_suspend_enter(), which executes from its virtual address
- replace explicit lr assignment plus branch with bl in cpu_resume(), which
  aligns it with stext() and secondary_startup()
- use adr_l for mpidr_hash reference, and fix the incorrect accompanying
  comment
- replace leading spaces with tabs, and add a bit of whitespace for
  readability

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

---
 arch/arm64/kernel/sleep.S | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

-- 
2.7.4


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Comments

Mark Rutland Aug. 24, 2016, 4:13 p.m. UTC | #1
On Wed, Aug 24, 2016 at 04:35:59PM +0200, Ard Biesheuvel wrote:
> This fixes a number of style issues in sleep.S. No functional changes are

> intended:

> - replace absolute literal references with relative references in

>   __cpu_suspend_enter(), which executes from its virtual address

> - replace explicit lr assignment plus branch with bl in cpu_resume(), which

>   aligns it with stext() and secondary_startup()

> - use adr_l for mpidr_hash reference, and fix the incorrect accompanying

>   comment


It looks like the comment was true until commit cabe1c81ea5be983 ("arm64:
Change cpu_resume() to enable mmu early then access sleep_sp by va"), which may
be worth calling out here.

> - replace leading spaces with tabs, and add a bit of whitespace for

>   readability

> 

> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>


Regardless of the above, this looks like a good improvement to me, for all
points mentioned in the commit message. FWIW:

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


Mark.

> ---

>  arch/arm64/kernel/sleep.S | 19 +++++++++----------

>  1 file changed, 9 insertions(+), 10 deletions(-)

> 

> diff --git a/arch/arm64/kernel/sleep.S b/arch/arm64/kernel/sleep.S

> index 182129b60fdf..bbc63099223b 100644

> --- a/arch/arm64/kernel/sleep.S

> +++ b/arch/arm64/kernel/sleep.S

> @@ -73,10 +73,9 @@ ENTRY(__cpu_suspend_enter)

>  	str	x2, [x0, #SLEEP_STACK_DATA_SYSTEM_REGS + CPU_CTX_SP]

>  

>  	/* find the mpidr_hash */

> -	ldr	x1, =sleep_save_stash

> -	ldr	x1, [x1]

> +	ldr_l	x1, sleep_save_stash

>  	mrs	x7, mpidr_el1

> -	ldr	x9, =mpidr_hash

> +	adr_l	x9, mpidr_hash

>  	ldr	x10, [x9, #MPIDR_HASH_MASK]

>  	/*

>  	 * Following code relies on the struct mpidr_hash

> @@ -95,14 +94,13 @@ ENTRY(__cpu_suspend_enter)

>  	mov	x0, #1

>  	ret

>  ENDPROC(__cpu_suspend_enter)

> -	.ltorg

>  

>  ENTRY(cpu_resume)

>  	bl	el2_setup		// if in EL2 drop to EL1 cleanly

> +	bl	__cpu_setup

>  	/* enable the MMU early - so we can access sleep_save_stash by va */

> -	adr_l	lr, __enable_mmu	/* __cpu_setup will return here */

>  	adr_l	x27, _resume_switched	/* __enable_mmu will branch here */

> -	b	__cpu_setup

> +	b	__enable_mmu

>  ENDPROC(cpu_resume)

>  

>  	.pushsection	".idmap.text", "ax"

> @@ -115,14 +113,15 @@ ENDPROC(_resume_switched)

>  

>  ENTRY(_cpu_resume)

>  	mrs	x1, mpidr_el1

> -	adrp	x8, mpidr_hash

> -	add x8, x8, #:lo12:mpidr_hash // x8 = struct mpidr_hash phys address

> -        /* retrieve mpidr_hash members to compute the hash */

> +	adr_l	x8, mpidr_hash		// x8 = struct mpidr_hash virt address

> +

> +	/* retrieve mpidr_hash members to compute the hash */

>  	ldr	x2, [x8, #MPIDR_HASH_MASK]

>  	ldp	w3, w4, [x8, #MPIDR_HASH_SHIFTS]

>  	ldp	w5, w6, [x8, #(MPIDR_HASH_SHIFTS + 8)]

>  	compute_mpidr_hash x7, x3, x4, x5, x6, x1, x2

> -        /* x7 contains hash index, let's use it to grab context pointer */

> +

> +	/* x7 contains hash index, let's use it to grab context pointer */

>  	ldr_l	x0, sleep_save_stash

>  	ldr	x0, [x0, x7, lsl #3]

>  	add	x29, x0, #SLEEP_STACK_DATA_CALLEE_REGS

> -- 

> 2.7.4

> 


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
diff mbox

Patch

diff --git a/arch/arm64/kernel/sleep.S b/arch/arm64/kernel/sleep.S
index 182129b60fdf..bbc63099223b 100644
--- a/arch/arm64/kernel/sleep.S
+++ b/arch/arm64/kernel/sleep.S
@@ -73,10 +73,9 @@  ENTRY(__cpu_suspend_enter)
 	str	x2, [x0, #SLEEP_STACK_DATA_SYSTEM_REGS + CPU_CTX_SP]
 
 	/* find the mpidr_hash */
-	ldr	x1, =sleep_save_stash
-	ldr	x1, [x1]
+	ldr_l	x1, sleep_save_stash
 	mrs	x7, mpidr_el1
-	ldr	x9, =mpidr_hash
+	adr_l	x9, mpidr_hash
 	ldr	x10, [x9, #MPIDR_HASH_MASK]
 	/*
 	 * Following code relies on the struct mpidr_hash
@@ -95,14 +94,13 @@  ENTRY(__cpu_suspend_enter)
 	mov	x0, #1
 	ret
 ENDPROC(__cpu_suspend_enter)
-	.ltorg
 
 ENTRY(cpu_resume)
 	bl	el2_setup		// if in EL2 drop to EL1 cleanly
+	bl	__cpu_setup
 	/* enable the MMU early - so we can access sleep_save_stash by va */
-	adr_l	lr, __enable_mmu	/* __cpu_setup will return here */
 	adr_l	x27, _resume_switched	/* __enable_mmu will branch here */
-	b	__cpu_setup
+	b	__enable_mmu
 ENDPROC(cpu_resume)
 
 	.pushsection	".idmap.text", "ax"
@@ -115,14 +113,15 @@  ENDPROC(_resume_switched)
 
 ENTRY(_cpu_resume)
 	mrs	x1, mpidr_el1
-	adrp	x8, mpidr_hash
-	add x8, x8, #:lo12:mpidr_hash // x8 = struct mpidr_hash phys address
-        /* retrieve mpidr_hash members to compute the hash */
+	adr_l	x8, mpidr_hash		// x8 = struct mpidr_hash virt address
+
+	/* retrieve mpidr_hash members to compute the hash */
 	ldr	x2, [x8, #MPIDR_HASH_MASK]
 	ldp	w3, w4, [x8, #MPIDR_HASH_SHIFTS]
 	ldp	w5, w6, [x8, #(MPIDR_HASH_SHIFTS + 8)]
 	compute_mpidr_hash x7, x3, x4, x5, x6, x1, x2
-        /* x7 contains hash index, let's use it to grab context pointer */
+
+	/* x7 contains hash index, let's use it to grab context pointer */
 	ldr_l	x0, sleep_save_stash
 	ldr	x0, [x0, x7, lsl #3]
 	add	x29, x0, #SLEEP_STACK_DATA_CALLEE_REGS