From: Geoff Levand Date: Wed, 27 Apr 2016 16:47:10 +0000 (+0100) Subject: UPSTREAM: arm64: Add new asm macro copy_page X-Git-Tag: firefly_0821_release~176^2~139 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=5f657f2582f468e8883abbeca9a0772a67156f26;p=firefly-linux-kernel-4.4.55.git UPSTREAM: arm64: Add new asm macro copy_page Kexec and hibernate need to copy pages of memory, but may not have all of the kernel mapped, and are unable to call copy_page(). Add a simplistic copy_page() macro, that can be inlined in these situations. lib/copy_page.S provides a bigger better version, but uses more registers. Signed-off-by: Geoff Levand [Changed asm label to 9998, added commit message] Signed-off-by: James Morse Acked-by: Catalin Marinas Signed-off-by: Will Deacon Change-Id: If23a454e211b1f57f8ba1a2a00b44dabf4b82932 (cherry picked from commit 5003dbde45961dd7ab3d8a09ab9ad8bcb604db40) Signed-off-by: Sami Tolvanen --- diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index 33bbb7ba7fb5..290e13428f4a 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -24,6 +24,7 @@ #define __ASM_ASSEMBLER_H #include +#include #include #include #include @@ -291,6 +292,24 @@ lr .req x30 // link register 9000: .endm +/* + * copy_page - copy src to dest using temp registers t1-t8 + */ + .macro copy_page dest:req src:req t1:req t2:req t3:req t4:req t5:req t6:req t7:req t8:req +9998: ldp \t1, \t2, [\src] + ldp \t3, \t4, [\src, #16] + ldp \t5, \t6, [\src, #32] + ldp \t7, \t8, [\src, #48] + add \src, \src, #64 + stnp \t1, \t2, [\dest] + stnp \t3, \t4, [\dest, #16] + stnp \t5, \t6, [\dest, #32] + stnp \t7, \t8, [\dest, #48] + add \dest, \dest, #64 + tst \src, #(PAGE_SIZE - 1) + b.ne 9998b + .endm + /* * Annotate a function as position independent, i.e., safe to be called before * the kernel virtual mapping is activated.