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MIPS: Loongson64: Probe CPU features via CPUCFG

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CPUCFG is a Loongson self-defined instruction used to mark CPU
features for Loongson processors started from Loongson-3A4000.

Slightly adjust cpu_probe_loongson function as well. Remove features
that already probed via decode_configs in processor's PRID case
and add a comment about TLBINV.

Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
This commit is contained in:
Jiaxun Yang 2020-04-30 11:18:35 +08:00 committed by Thomas Bogendoerfer
parent e9dfbaaeef
commit da1bd29742
1 changed files with 37 additions and 8 deletions
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45
arch/mips/kernel/cpu-probe.c
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@ -1932,8 +1932,35 @@ platform:
} }
} }
#ifdef CONFIG_CPU_LOONGSON64
#include <loongson_regs.h>
static inline void decode_cpucfg(struct cpuinfo_mips *c)
{
u32 cfg1 = read_cpucfg(LOONGSON_CFG1);
u32 cfg2 = read_cpucfg(LOONGSON_CFG2);
u32 cfg3 = read_cpucfg(LOONGSON_CFG3);
if (cfg1 & LOONGSON_CFG1_MMI)
c->ases |= MIPS_ASE_LOONGSON_MMI;
if (cfg2 & LOONGSON_CFG2_LEXT1)
c->ases |= MIPS_ASE_LOONGSON_EXT;
if (cfg2 & LOONGSON_CFG2_LEXT2)
c->ases |= MIPS_ASE_LOONGSON_EXT2;
if (cfg2 & LOONGSON_CFG2_LSPW)
c->options |= MIPS_CPU_LDPTE;
if (cfg3 & LOONGSON_CFG3_LCAMP)
c->ases |= MIPS_ASE_LOONGSON_CAM;
}
static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu) static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu)
{ {
decode_configs(c);
switch (c->processor_id & PRID_IMP_MASK) { switch (c->processor_id & PRID_IMP_MASK) {
case PRID_IMP_LOONGSON_64R: /* Loongson-64 Reduced */ case PRID_IMP_LOONGSON_64R: /* Loongson-64 Reduced */
switch (c->processor_id & PRID_REV_MASK) { switch (c->processor_id & PRID_REV_MASK) {
@ -1947,7 +1974,6 @@ static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu)
set_isa(c, MIPS_CPU_ISA_M64R2); set_isa(c, MIPS_CPU_ISA_M64R2);
break; break;
} }
decode_configs(c);
c->writecombine = _CACHE_UNCACHED_ACCELERATED; c->writecombine = _CACHE_UNCACHED_ACCELERATED;
c->ases |= (MIPS_ASE_LOONGSON_MMI | MIPS_ASE_LOONGSON_EXT | c->ases |= (MIPS_ASE_LOONGSON_MMI | MIPS_ASE_LOONGSON_EXT |
MIPS_ASE_LOONGSON_EXT2); MIPS_ASE_LOONGSON_EXT2);
@ -1969,9 +1995,12 @@ static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu)
set_isa(c, MIPS_CPU_ISA_M64R2); set_isa(c, MIPS_CPU_ISA_M64R2);
break; break;
} }
/*
decode_configs(c); * Loongson-3 Classic did not implement MIPS standard TLBINV
c->options |= MIPS_CPU_FTLB | MIPS_CPU_TLBINV | MIPS_CPU_LDPTE; * but implemented TLBINVF and EHINV. As currently we're only
* using these two features, enable MIPS_CPU_TLBINV as well.
*/
c->options |= MIPS_CPU_TLBINV | MIPS_CPU_LDPTE;
c->writecombine = _CACHE_UNCACHED_ACCELERATED; c->writecombine = _CACHE_UNCACHED_ACCELERATED;
c->ases |= (MIPS_ASE_LOONGSON_MMI | MIPS_ASE_LOONGSON_CAM | c->ases |= (MIPS_ASE_LOONGSON_MMI | MIPS_ASE_LOONGSON_CAM |
MIPS_ASE_LOONGSON_EXT | MIPS_ASE_LOONGSON_EXT2); MIPS_ASE_LOONGSON_EXT | MIPS_ASE_LOONGSON_EXT2);
@ -1981,17 +2010,17 @@ static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu)
__cpu_name[cpu] = "ICT Loongson-3"; __cpu_name[cpu] = "ICT Loongson-3";
set_elf_platform(cpu, "loongson3a"); set_elf_platform(cpu, "loongson3a");
set_isa(c, MIPS_CPU_ISA_M64R2); set_isa(c, MIPS_CPU_ISA_M64R2);
decode_configs(c); decode_cpucfg(c);
c->options |= MIPS_CPU_FTLB | MIPS_CPU_TLBINV | MIPS_CPU_LDPTE;
c->writecombine = _CACHE_UNCACHED_ACCELERATED; c->writecombine = _CACHE_UNCACHED_ACCELERATED;
c->ases |= (MIPS_ASE_LOONGSON_MMI | MIPS_ASE_LOONGSON_CAM |
MIPS_ASE_LOONGSON_EXT | MIPS_ASE_LOONGSON_EXT2);
break; break;
default: default:
panic("Unknown Loongson Processor ID!"); panic("Unknown Loongson Processor ID!");
break; break;
} }
} }
#else
static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu) { }
#endif
static inline void cpu_probe_ingenic(struct cpuinfo_mips *c, unsigned int cpu) static inline void cpu_probe_ingenic(struct cpuinfo_mips *c, unsigned int cpu)
{ {