MIPS: Loongson: Fix cpu_probe_loongson() again

Commit 7db5e9e9e5e6c10d7d ("MIPS: loongson64: fix FTLB configuration")
move decode_configs() from the beginning of cpu_probe_loongson() to the
end in order to fix FTLB configuration. However, it breaks the CPUCFG
decoding because decode_configs() use "c->options = xxxx" rather than
"c->options |= xxxx", all information get from CPUCFG by decode_cpucfg()
is lost.

This causes error when creating a KVM guest on Loongson-3A4000:
Exception Code: 4 not handled @ PC: 0000000087ad5981, inst: 0xcb7a1898 BadVaddr: 0x0 Status: 0x0

Fix this by moving the c->cputype setting to the beginning and moving
decode_configs() after that.

Fixes: 7db5e9e9e5e6c10d7d ("MIPS: loongson64: fix FTLB configuration")
Cc: stable@vger.kernel.org
Cc: Huang Pei <huangpei@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c
index e79adcb..b406d8b 100644 (file)
--- a/arch/mips/kernel/cpu-probe.c
+++ b/arch/mips/kernel/cpu-probe.c
@@ -1677,7 +1677,10 @@ static inline void decode_cpucfg(struct cpuinfo_mips *c)
 
 static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu)
 {
+       c->cputype = CPU_LOONGSON64;
+
        /* All Loongson processors covered here define ExcCode 16 as GSExc. */
+       decode_configs(c);
        c->options |= MIPS_CPU_GSEXCEX;
 
        switch (c->processor_id & PRID_IMP_MASK) {
@@ -1687,7 +1690,6 @@ static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu)
                case PRID_REV_LOONGSON2K_R1_1:
                case PRID_REV_LOONGSON2K_R1_2:
                case PRID_REV_LOONGSON2K_R1_3:
-                       c->cputype = CPU_LOONGSON64;
                        __cpu_name[cpu] = "Loongson-2K";
                        set_elf_platform(cpu, "gs264e");
                        set_isa(c, MIPS_CPU_ISA_M64R2);
@@ -1700,14 +1702,12 @@ static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu)
                switch (c->processor_id & PRID_REV_MASK) {
                case PRID_REV_LOONGSON3A_R2_0:
                case PRID_REV_LOONGSON3A_R2_1:
-                       c->cputype = CPU_LOONGSON64;
                        __cpu_name[cpu] = "ICT Loongson-3";
                        set_elf_platform(cpu, "loongson3a");
                        set_isa(c, MIPS_CPU_ISA_M64R2);
                        break;
                case PRID_REV_LOONGSON3A_R3_0:
                case PRID_REV_LOONGSON3A_R3_1:
-                       c->cputype = CPU_LOONGSON64;
                        __cpu_name[cpu] = "ICT Loongson-3";
                        set_elf_platform(cpu, "loongson3a");
                        set_isa(c, MIPS_CPU_ISA_M64R2);
@@ -1727,7 +1727,6 @@ static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu)
                c->ases &= ~MIPS_ASE_VZ; /* VZ of Loongson-3A2000/3000 is incomplete */
                break;
        case PRID_IMP_LOONGSON_64G:
-               c->cputype = CPU_LOONGSON64;
                __cpu_name[cpu] = "ICT Loongson-3";
                set_elf_platform(cpu, "loongson3a");
                set_isa(c, MIPS_CPU_ISA_M64R2);
@@ -1737,8 +1736,6 @@ static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu)
                panic("Unknown Loongson Processor ID!");
                break;
        }
-
-       decode_configs(c);
 }
 #else
 static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu) { }