diff mbox series

[06/12] ARM: head.S: use PC-relative insn sequence for secondary_data

Message ID 20200914095706.3985-7-ardb@kernel.org
State Accepted
Commit 91580f0dbf24c6d616091526a900213bc7aa48fe
Headers show
Series ARM: use adr_l/ldr_l macros for PC-relative references | expand

Commit Message

Ard Biesheuvel Sept. 14, 2020, 9:57 a.m. UTC
Replace the open coded PC relative offset calculations with adr_l
and ldr_l invocations. This removes some open coded arithmetic
involving virtual addresses, avoids literal pools on v7+, and slightly
reduces the footprint of the code.

Note that it also removes a stale comment about the contents of r6.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 arch/arm/kernel/head.S | 19 ++++---------------
 1 file changed, 4 insertions(+), 15 deletions(-)
diff mbox series

Patch

diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S
index 7d8e2a296216..40407a4727e0 100644
--- a/arch/arm/kernel/head.S
+++ b/arch/arm/kernel/head.S
@@ -383,10 +383,8 @@  ENTRY(secondary_startup)
 	/*
 	 * Use the page tables supplied from  __cpu_up.
 	 */
-	adr	r4, __secondary_data
-	ldmia	r4, {r5, r7, r12}		@ address to jump to after
-	sub	lr, r4, r5			@ mmu has been enabled
-	add	r3, r7, lr
+	adr_l	r3, secondary_data
+	mov_l	r12, __secondary_switched
 	ldrd	r4, r5, [r3, #0]		@ get secondary_data.pgdir
 ARM_BE8(eor	r4, r4, r5)			@ Swap r5 and r4 in BE:
 ARM_BE8(eor	r5, r4, r5)			@ it can be done in 3 steps
@@ -401,22 +399,13 @@  ARM_BE8(eor	r4, r4, r5)			@ without using a temp reg.
 ENDPROC(secondary_startup)
 ENDPROC(secondary_startup_arm)
 
-	/*
-	 * r6  = &secondary_data
-	 */
 ENTRY(__secondary_switched)
-	ldr	sp, [r7, #12]			@ get secondary_data.stack
+	ldr_l	r7, secondary_data + 12		@ get secondary_data.stack
+	mov	sp, r7
 	mov	fp, #0
 	b	secondary_start_kernel
 ENDPROC(__secondary_switched)
 
-	.align
-
-	.type	__secondary_data, %object
-__secondary_data:
-	.long	.
-	.long	secondary_data
-	.long	__secondary_switched
 #endif /* defined(CONFIG_SMP) */