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| author | Helge Deller <deller@gmx.de> | 2019-08-12 19:11:06 +0200 |
|---|---|---|
| committer | Helge Deller <deller@gmx.de> | 2019-08-12 19:17:39 +0200 |
| commit | 82992fc70f98dee091faa926eb5cecadda5c84f4 (patch) | |
| tree | 915078a06f9ed8bd736bbd29d52eca237af19b91 /arch/parisc/include | |
| parent | parisc: Add assembly implementations for memset, strlen, strcpy, strncpy and ... (diff) | |
| download | linux-82992fc70f98dee091faa926eb5cecadda5c84f4.tar.xz linux-82992fc70f98dee091faa926eb5cecadda5c84f4.zip | |
parisc: Add ALTERNATIVE_CODE() and ALT_COND_RUN_ON_QEMU
The macro ALTERNATIVE_CODE() allows assembly code to patch in a series
of new assembler statements given at a specific start address.
The ALT_COND_RUN_ON_QEMU condition is true if the kernel is started in a
qemu emulation.
Signed-off-by: Helge Deller <deller@gmx.de>
Diffstat (limited to 'arch/parisc/include')
| -rw-r--r-- | arch/parisc/include/asm/alternative.h | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/arch/parisc/include/asm/alternative.h b/arch/parisc/include/asm/alternative.h index 793d8baa3a10..0ec54f43d6d2 100644 --- a/arch/parisc/include/asm/alternative.h +++ b/arch/parisc/include/asm/alternative.h @@ -8,6 +8,7 @@ #define ALT_COND_NO_ICACHE 0x04 /* if system has no i-cache */ #define ALT_COND_NO_SPLIT_TLB 0x08 /* if split_tlb == 0 */ #define ALT_COND_NO_IOC_FDC 0x10 /* if I/O cache does not need flushes */ +#define ALT_COND_RUN_ON_QEMU 0x20 /* if running on QEMU */ #define INSN_PxTLB 0x02 /* modify pdtlb, pitlb */ #define INSN_NOP 0x08000240 /* nop */ @@ -21,7 +22,7 @@ struct alt_instr { s32 orig_offset; /* offset to original instructions */ - u32 len; /* end of original instructions */ + s32 len; /* end of original instructions */ u32 cond; /* see ALT_COND_XXX */ u32 replacement; /* replacement instruction or code */ }; @@ -40,12 +41,20 @@ void apply_alternatives(struct alt_instr *start, struct alt_instr *end, #else +/* to replace one single instructions by a new instruction */ #define ALTERNATIVE(from, to, cond, replacement)\ .section .altinstructions, "aw" ! \ .word (from - .), (to - from)/4 ! \ .word cond, replacement ! \ .previous +/* to replace multiple instructions by new code */ +#define ALTERNATIVE_CODE(from, num_instructions, cond, new_instr_ptr)\ + .section .altinstructions, "aw" ! \ + .word (from - .), -num_instructions ! \ + .word cond, (new_instr_ptr - .) ! \ + .previous + #endif /* __ASSEMBLY__ */ #endif /* __ASM_PARISC_ALTERNATIVE_H */ |