MIPS: Loongson64: Set timer mode in cpu-probe

Loongson64 C and G processors have EXTIMER feature which is conflicting with CP0 counter. Although the processor resets in EXTIMER disabled & INTIMER enabled mode, which is compatible with MIPS CP0 compare, firmware may attempt to enable EXTIMER and interfere CP0 compare. Set timer mode back to MIPS compatible mode to fix booting on systems with such firmware before we have an actual driver for EXTIMER. Cc: [email protected] Signed-off-by: Jiaxun Yang <[email protected]> Signed-off-by: Thomas Bogendoerfer <[email protected]>
mj22226 · Aug 8, 2024 · 1cb6ab4 · 1cb6ab4
1 parent 8400291
commit 1cb6ab4
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c
@@ -1724,12 +1724,16 @@ static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu)
 		c->ases |= (MIPS_ASE_LOONGSON_MMI | MIPS_ASE_LOONGSON_CAM |
 			MIPS_ASE_LOONGSON_EXT | MIPS_ASE_LOONGSON_EXT2);
 		c->ases &= ~MIPS_ASE_VZ; /* VZ of Loongson-3A2000/3000 is incomplete */
+		change_c0_config6(LOONGSON_CONF6_EXTIMER | LOONGSON_CONF6_INTIMER,
+				  LOONGSON_CONF6_INTIMER);
 		break;
 	case PRID_IMP_LOONGSON_64G:
 		__cpu_name[cpu] = "ICT Loongson-3";
 		set_elf_platform(cpu, "loongson3a");
 		set_isa(c, MIPS_CPU_ISA_M64R2);
 		decode_cpucfg(c);
+		change_c0_config6(LOONGSON_CONF6_EXTIMER | LOONGSON_CONF6_INTIMER,
+				  LOONGSON_CONF6_INTIMER);
 		break;
 	default:
 		panic("Unknown Loongson Processor ID!");