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| author | Ard Biesheuvel <ard.biesheuvel@linaro.org> | 2017-07-15 18:23:13 +0200 |
|---|---|---|
| committer | Mark Rutland <mark.rutland@arm.com> | 2017-08-15 19:35:47 +0200 |
| commit | 8ea41b11ef746e1ac97f8c90911e5c61f8bd5cc0 (patch) | |
| tree | 68ad3c4487ce3ae68ae2b4b6f32519ca60ccf19c | |
| parent | arm64: factor out entry stack manipulation (diff) | |
| download | linux-8ea41b11ef746e1ac97f8c90911e5c61f8bd5cc0.tar.xz linux-8ea41b11ef746e1ac97f8c90911e5c61f8bd5cc0.zip | |
arm64: assembler: allow adr_this_cpu to use the stack pointer
Given that adr_this_cpu already requires a temp register in addition
to the destination register, tweak the instruction sequence so that sp
may be used as well.
This will simplify switching to per-cpu stacks in subsequent patches. While
this limits the range of adr_this_cpu, to +/-4GiB, we don't currently use
adr_this_cpu in modules, and this is not problematic for the main kernel image.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
[Mark: add more commit text]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Tested-by: Laura Abbott <labbott@redhat.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
| -rw-r--r-- | arch/arm64/include/asm/assembler.h | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index 610a42018241..2f2bd5192b5e 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -230,12 +230,18 @@ lr .req x30 // link register .endm /* - * @dst: Result of per_cpu(sym, smp_processor_id()) + * @dst: Result of per_cpu(sym, smp_processor_id()), can be SP for + * non-module code * @sym: The name of the per-cpu variable * @tmp: scratch register */ .macro adr_this_cpu, dst, sym, tmp +#ifndef MODULE + adrp \tmp, \sym + add \dst, \tmp, #:lo12:\sym +#else adr_l \dst, \sym +#endif mrs \tmp, tpidr_el1 add \dst, \dst, \tmp .endm |