diff options
| -rw-r--r-- | arch/mips/include/asm/mipsregs.h | 4 | ||||
| -rw-r--r-- | arch/mips/kernel/cpu-probe.c | 7 |
2 files changed, 11 insertions, 0 deletions
diff --git a/arch/mips/include/asm/mipsregs.h b/arch/mips/include/asm/mipsregs.h index 1e6966e8527e..bdbdc19a2b8f 100644 --- a/arch/mips/include/asm/mipsregs.h +++ b/arch/mips/include/asm/mipsregs.h @@ -689,6 +689,9 @@ #define MIPS_CONF7_IAR (_ULCAST_(1) << 10) #define MIPS_CONF7_AR (_ULCAST_(1) << 16) +/* Ingenic Config7 bits */ +#define MIPS_CONF7_BTB_LOOP_EN (_ULCAST_(1) << 4) + /* Config7 Bits specific to MIPS Technologies. */ /* Performance counters implemented Per TC */ @@ -2813,6 +2816,7 @@ __BUILD_SET_C0(status) __BUILD_SET_C0(cause) __BUILD_SET_C0(config) __BUILD_SET_C0(config5) +__BUILD_SET_C0(config7) __BUILD_SET_C0(intcontrol) __BUILD_SET_C0(intctl) __BUILD_SET_C0(srsmap) diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c index 9635c1db3ae6..e654ffc1c8a0 100644 --- a/arch/mips/kernel/cpu-probe.c +++ b/arch/mips/kernel/cpu-probe.c @@ -1964,6 +1964,13 @@ static inline void cpu_probe_ingenic(struct cpuinfo_mips *c, unsigned int cpu) c->cputype = CPU_JZRISC; c->writecombine = _CACHE_UNCACHED_ACCELERATED; __cpu_name[cpu] = "Ingenic JZRISC"; + /* + * The XBurst core by default attempts to avoid branch target + * buffer lookups by detecting & special casing loops. This + * feature will cause BogoMIPS and lpj calculate in error. + * Set cp0 config7 bit 4 to disable this feature. + */ + set_c0_config7(MIPS_CONF7_BTB_LOOP_EN); break; default: panic("Unknown Ingenic Processor ID!"); |