[PATCH 05/12] ARM: head-common.S: use PC-relative insn sequence for idmap creation

[Ard Biesheuvel]

Replace the open coded PC relative offset calculations involving
__turn_mmu_on and __turn_mmu_on_end with a pair of adr_l invocations.
This removes some open coded arithmetic involving virtual addresses,
avoids literal pools on v7+, and slightly reduces the footprint of the
code.

Signed-off-by: Ard Biesheuvel <ardb at kernel.org>
---
 arch/arm/kernel/head.S | 12 ++----------
 1 file changed, 2 insertions(+), 10 deletions(-)

diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S
index f8904227e7fd..7d8e2a296216 100644
--- a/arch/arm/kernel/head.S
+++ b/arch/arm/kernel/head.S
@@ -224,11 +224,8 @@ __create_page_tables:
 	 * Create identity mapping to cater for __enable_mmu.
 	 * This identity mapping will be removed by paging_init().
 	 */
-	adr	r0, __turn_mmu_on_loc
-	ldmia	r0, {r3, r5, r6}
-	sub	r0, r0, r3			@ virt->phys offset
-	add	r5, r5, r0			@ phys __turn_mmu_on
-	add	r6, r6, r0			@ phys __turn_mmu_on_end
+	adr_l	r5, __turn_mmu_on		@ _pa(__turn_mmu_on)
+	adr_l	r6, __turn_mmu_on_end		@ _pa(__turn_mmu_on_end)
 	mov	r5, r5, lsr #SECTION_SHIFT
 	mov	r6, r6, lsr #SECTION_SHIFT
 
@@ -351,11 +348,6 @@ __create_page_tables:
 	ret	lr
 ENDPROC(__create_page_tables)
 	.ltorg
-	.align
-__turn_mmu_on_loc:
-	.long	.
-	.long	__turn_mmu_on
-	.long	__turn_mmu_on_end
 
 #if defined(CONFIG_SMP)
 	.text
-- 
2.17.1