Commit da1bd297 authored by Jiaxun Yang's avatar Jiaxun Yang Committed by Thomas Bogendoerfer
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MIPS: Loongson64: Probe CPU features via CPUCFG 



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: default avatarJiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: default avatarThomas Bogendoerfer <tsbogend@alpha.franken.de>
parent e9dfbaae

arch/mips/kernel/cpu-probe.c

+37 −8
Original line number Diff line number Diff line
@@ -1932,8 +1932,35 @@ static inline void cpu_probe_cavium(struct cpuinfo_mips *c, unsigned int cpu) 
	}

}



#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)

{

	decode_configs(c);



	switch (c->processor_id & PRID_IMP_MASK) {

	case PRID_IMP_LOONGSON_64R: /* Loongson-64 Reduced */

		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);

			break;

		}

		decode_configs(c);

		c->writecombine = _CACHE_UNCACHED_ACCELERATED;

		c->ases |= (MIPS_ASE_LOONGSON_MMI | MIPS_ASE_LOONGSON_EXT |

				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);

			break;

		}



		decode_configs(c);

		c->options |= MIPS_CPU_FTLB | MIPS_CPU_TLBINV | MIPS_CPU_LDPTE;

		/*

		 * Loongson-3 Classic did not implement MIPS standard TLBINV

		 * 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->ases |= (MIPS_ASE_LOONGSON_MMI | MIPS_ASE_LOONGSON_CAM |

			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";

		set_elf_platform(cpu, "loongson3a");

		set_isa(c, MIPS_CPU_ISA_M64R2);

		decode_configs(c);

		c->options |= MIPS_CPU_FTLB | MIPS_CPU_TLBINV | MIPS_CPU_LDPTE;

		decode_cpucfg(c);

		c->writecombine = _CACHE_UNCACHED_ACCELERATED;

		c->ases |= (MIPS_ASE_LOONGSON_MMI | MIPS_ASE_LOONGSON_CAM |

			MIPS_ASE_LOONGSON_EXT | MIPS_ASE_LOONGSON_EXT2);

		break;

	default:

		panic("Unknown Loongson Processor ID!");

		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)

{