diff options
Diffstat (limited to 'arch/mips/kernel/cpu-probe.c')
| -rw-r--r-- | arch/mips/kernel/cpu-probe.c | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c index da2820991e21..b8ec35737606 100644 --- a/arch/mips/kernel/cpu-probe.c +++ b/arch/mips/kernel/cpu-probe.c @@ -672,6 +672,52 @@ static int set_ftlb_enable(struct cpuinfo_mips *c, enum ftlb_flags flags) return 0; } +static int mm_config(struct cpuinfo_mips *c) +{ + unsigned int config0, update, mm; + + config0 = read_c0_config(); + mm = config0 & MIPS_CONF_MM; + + /* + * It's implementation dependent what type of write-merge is supported + * and whether it can be enabled/disabled. If it is settable lets make + * the merging allowed by default. Some platforms might have + * write-through caching unsupported. In this case just ignore the + * CP0.Config.MM bit field value. + */ + switch (c->cputype) { + case CPU_24K: + case CPU_34K: + case CPU_74K: + case CPU_P5600: + case CPU_P6600: + c->options |= MIPS_CPU_MM_FULL; + update = MIPS_CONF_MM_FULL; + break; + case CPU_1004K: + case CPU_1074K: + case CPU_INTERAPTIV: + case CPU_PROAPTIV: + mm = 0; + fallthrough; + default: + update = 0; + break; + } + + if (update) { + config0 = (config0 & ~MIPS_CONF_MM) | update; + write_c0_config(config0); + } else if (mm == MIPS_CONF_MM_SYSAD) { + c->options |= MIPS_CPU_MM_SYSAD; + } else if (mm == MIPS_CONF_MM_FULL) { + c->options |= MIPS_CPU_MM_FULL; + } + + return 0; +} + static inline unsigned int decode_config0(struct cpuinfo_mips *c) { unsigned int config0; @@ -1763,6 +1809,8 @@ static inline void cpu_probe_mips(struct cpuinfo_mips *c, unsigned int cpu) spram_config(); + mm_config(c); + switch (__get_cpu_type(c->cputype)) { case CPU_M5150: case CPU_P5600: |