diff options
Diffstat (limited to 'sys/arch/mips64/include/asm.h')
| -rw-r--r-- | sys/arch/mips64/include/asm.h | 35 |
1 files changed, 34 insertions, 1 deletions
diff --git a/sys/arch/mips64/include/asm.h b/sys/arch/mips64/include/asm.h index 8de2128eb92..127ad53528b 100644 --- a/sys/arch/mips64/include/asm.h +++ b/sys/arch/mips64/include/asm.h @@ -1,4 +1,4 @@ -/* $OpenBSD: asm.h,v 1.17 2012/09/29 19:02:25 miod Exp $ */ +/* $OpenBSD: asm.h,v 1.18 2012/09/29 21:37:03 miod Exp $ */ /* * Copyright (c) 2001-2002 Opsycon AB (www.opsycon.se / www.opsycon.com) @@ -174,12 +174,29 @@ #define PTR_VAL .dword #endif +/* + * The following macros are here to benefit the R8000 processor: + * - all coprocessor 0 control registers are 64-bit + * - the regular nop (sll zero, zero, 0) has the drawback of using the + * shifter, potentially breaking instruction dispatch if occuring after + * another instruction using the shifter. + */ +#ifdef CPU_R8000 +#define SSNOP sll zero, zero, 1 /* ``ssnop'' */ +#define NOP PTR_ADDU zero, zero, zero /* real nop for R8000 */ +#define DMFC0 SSNOP; dmfc0 +#define DMTC0 SSNOP; dmtc0 +#define MFC0 SSNOP; dmfc0 +#define MTC0 SSNOP; dmtc0 +#define ERET eret; mul k0, k0; mflo k0 +#else #define NOP nop #define DMFC0 dmfc0 #define DMTC0 dmtc0 #define MFC0 mfc0 #define MTC0 mtc0 #define ERET sync; eret +#endif /* * Define -pg profile entry code. @@ -330,6 +347,22 @@ x: ; \ #define TLB_HAZARD NOP; NOP; NOP; NOP #endif +#ifdef CPU_R8000 +/* + * The R8000 needs a lot of care inserting proper superscalar dispatch breaks + * to prevent unwanted side-effects or avoid collisions on the internal MiscBus + * and the E and W stages of the pipelines. + * + * The following settings are a bit pessimistic, but better run safely than + * not at all. + */ +#define PRE_MFC0_ADDR_HAZARD .align 5; SSNOP +#define MFC0_HAZARD SSNOP +#define MTC0_HAZARD SSNOP; SSNOP; SSNOP +#define MTC0_SR_IE_HAZARD MTC0_HAZARD; SSNOP +#define MTC0_SR_CU_HAZARD MTC0_HAZARD; SSNOP +#endif + /* Hazard between {d,}mfc0 of COP_0_VADDR */ #ifndef PRE_MFC0_ADDR_HAZARD #define PRE_MFC0_ADDR_HAZARD /* nothing */ |