[PATCH 11/12] ARM: head.S: use PC relative insn sequence to calculate PHYS_OFFSET
Ard Biesheuvel
ardb at kernel.org
Mon Sep 14 05:57:05 EDT 2020
Replace the open coded arithmetic with a simple adr_l/sub pair. 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 | 10 ++--------
1 file changed, 2 insertions(+), 8 deletions(-)
diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S
index 6f334df5d3b9..2e6127b2662e 100644
--- a/arch/arm/kernel/head.S
+++ b/arch/arm/kernel/head.S
@@ -103,10 +103,8 @@ ENTRY(stext)
#endif
#ifndef CONFIG_XIP_KERNEL
- adr r3, 2f
- ldmia r3, {r4, r8}
- sub r4, r3, r4 @ (PHYS_OFFSET - PAGE_OFFSET)
- add r8, r8, r4 @ PHYS_OFFSET
+ adr_l r8, _text @ __pa(_text)
+ sub r8, r8, #TEXT_OFFSET @ PHYS_OFFSET
#else
ldr r8, =PLAT_PHYS_OFFSET @ always constant in this case
#endif
@@ -158,10 +156,6 @@ ENTRY(stext)
1: b __enable_mmu
ENDPROC(stext)
.ltorg
-#ifndef CONFIG_XIP_KERNEL
-2: .long .
- .long PAGE_OFFSET
-#endif
/*
* Setup the initial page tables. We only setup the barest
--
2.17.1
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