From 0dfa1c12f300d06f95d861d2718ef198e37473a6 Mon Sep 17 00:00:00 2001 From: James Hogan Date: Fri, 20 May 2016 23:28:37 +0100 Subject: [PATCH] MIPS: Add inline asm encoding helpers To allow simplification of macros which use inline assembly to explicitly encode instructions, add a few simple abstractions to mipsregs.h which expand to specific microMIPS or normal MIPS encodings depending on what type of kernel is being built: _ASM_INSN_IF_MIPS(_enc) : Emit a 32bit MIPS instruction if microMIPS is not enabled. _ASM_INSN32_IF_MM(_enc) : Emit a 32bit microMIPS instruction if enabled. _ASM_INSN16_IF_MM(_enc) : Emit a 16bit microMIPS instruction if enabled. The macros can be used one after another since the MIPS / microMIPS macros are mutually exclusive, for example: __asm__ __volatile__( ".set push\n\t" ".set noat\n\t" "# mfgc0 $1, $%1, %2\n\t" _ASM_INSN_IF_MIPS(0x40610000 | %1 << 11 | %2) _ASM_INSN32_IF_MM(0x002004fc | %1 << 16 | %2 << 11) "move %0, $1\n\t" ".set pop" : "=r" (__res) : "i" (source), "i" (sel)); Signed-off-by: James Hogan Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/13310/ Signed-off-by: Ralf Baechle --- arch/mips/include/asm/mipsregs.h | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) diff --git a/arch/mips/include/asm/mipsregs.h b/arch/mips/include/asm/mipsregs.h index 044219e741cc..1ce2c72ab88d 100644 --- a/arch/mips/include/asm/mipsregs.h +++ b/arch/mips/include/asm/mipsregs.h @@ -1048,6 +1048,33 @@ static inline int mm_insn_16bit(u16 insn) return (opcode >= 1 && opcode <= 3) ? 1 : 0; } +/* + * Helper macros for generating raw instruction encodings in inline asm. + */ +#ifdef CONFIG_CPU_MICROMIPS +#define _ASM_INSN16_IF_MM(_enc) \ + ".insn\n\t" \ + ".hword (" #_enc ")\n\t" +#define _ASM_INSN32_IF_MM(_enc) \ + ".insn\n\t" \ + ".hword ((" #_enc ") >> 16)\n\t" \ + ".hword ((" #_enc ") & 0xffff)\n\t" +#else +#define _ASM_INSN_IF_MIPS(_enc) \ + ".insn\n\t" \ + ".word (" #_enc ")\n\t" +#endif + +#ifndef _ASM_INSN16_IF_MM +#define _ASM_INSN16_IF_MM(_enc) +#endif +#ifndef _ASM_INSN32_IF_MM +#define _ASM_INSN32_IF_MM(_enc) +#endif +#ifndef _ASM_INSN_IF_MIPS +#define _ASM_INSN_IF_MIPS(_enc) +#endif + /* * TLB Invalidate Flush */