diff options
| -rw-r--r-- | arch/mips/include/asm/cpu-features.h | 4 | ||||
| -rw-r--r-- | arch/mips/include/asm/cpu.h | 1 | ||||
| -rw-r--r-- | arch/mips/include/asm/mipsregs.h | 3 | ||||
| -rw-r--r-- | arch/mips/kernel/cpu-probe.c | 3 | ||||
| -rw-r--r-- | arch/mips/kernel/genex.S | 14 | ||||
| -rw-r--r-- | arch/mips/kernel/traps.c | 35 |
6 files changed, 60 insertions, 0 deletions
diff --git a/arch/mips/include/asm/cpu-features.h b/arch/mips/include/asm/cpu-features.h index 0b1bc7ed913b..78cf7e300f12 100644 --- a/arch/mips/include/asm/cpu-features.h +++ b/arch/mips/include/asm/cpu-features.h @@ -572,6 +572,10 @@ # define cpu_has_ftlbparex __opt(MIPS_CPU_FTLBPAREX) #endif +#ifndef cpu_has_gsexcex +# define cpu_has_gsexcex __opt(MIPS_CPU_GSEXCEX) +#endif + #ifdef CONFIG_SMP /* * Some systems share FTLB RAMs between threads within a core (siblings in diff --git a/arch/mips/include/asm/cpu.h b/arch/mips/include/asm/cpu.h index 9d08bd33b11f..388a82f28a87 100644 --- a/arch/mips/include/asm/cpu.h +++ b/arch/mips/include/asm/cpu.h @@ -428,6 +428,7 @@ enum cpu_type_enum { #define MIPS_CPU_MM_FULL BIT_ULL(59) /* CPU supports write-through full merge */ #define MIPS_CPU_MAC_2008_ONLY BIT_ULL(60) /* CPU Only support MAC2008 Fused multiply-add instruction */ #define MIPS_CPU_FTLBPAREX BIT_ULL(61) /* CPU has FTLB parity exception */ +#define MIPS_CPU_GSEXCEX BIT_ULL(62) /* CPU has GSExc exception */ /* * CPU ASE encodings diff --git a/arch/mips/include/asm/mipsregs.h b/arch/mips/include/asm/mipsregs.h index 5ba268266d16..4ddc12e4444a 100644 --- a/arch/mips/include/asm/mipsregs.h +++ b/arch/mips/include/asm/mipsregs.h @@ -474,6 +474,9 @@ /* Implementation specific trap codes used by MIPS cores */ #define MIPS_EXCCODE_TLBPAR 16 /* TLB parity error exception */ +/* Implementation specific trap codes used by Loongson cores */ +#define LOONGSON_EXCCODE_GSEXC 16 /* Loongson-specific exception */ + /* * Bits in the coprocessor 0 config register. */ diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c index 519d101fd009..e2955f1f6316 100644 --- a/arch/mips/kernel/cpu-probe.c +++ b/arch/mips/kernel/cpu-probe.c @@ -2043,6 +2043,9 @@ static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu) { decode_configs(c); + /* All Loongson processors covered here define ExcCode 16 as GSExc. */ + c->options |= MIPS_CPU_GSEXCEX; + switch (c->processor_id & PRID_IMP_MASK) { case PRID_IMP_LOONGSON_64R: /* Loongson-64 Reduced */ switch (c->processor_id & PRID_REV_MASK) { diff --git a/arch/mips/kernel/genex.S b/arch/mips/kernel/genex.S index a1b966f3578e..bcce32a3de10 100644 --- a/arch/mips/kernel/genex.S +++ b/arch/mips/kernel/genex.S @@ -498,6 +498,19 @@ NESTED(nmi_handler, PT_SIZE, sp) KMODE .endm + .macro __build_clear_gsexc + .set push + /* + * We need to specify a selector to access the CP0.Diag1 (GSCause) + * register. All GSExc-equipped processors have MIPS32. + */ + .set mips32 + mfc0 a1, CP0_DIAGNOSTIC1 + .set pop + TRACE_IRQS_ON + STI + .endm + .macro __BUILD_silent exception .endm @@ -556,6 +569,7 @@ NESTED(nmi_handler, PT_SIZE, sp) BUILD_HANDLER fpe fpe fpe silent /* #15 */ #endif BUILD_HANDLER ftlb ftlb none silent /* #16 */ + BUILD_HANDLER gsexc gsexc gsexc silent /* #16 */ BUILD_HANDLER msa msa sti silent /* #21 */ BUILD_HANDLER mdmx mdmx sti silent /* #22 */ #ifdef CONFIG_HARDWARE_WATCHPOINTS diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c index 9c37a6997259..b95ef98fc847 100644 --- a/arch/mips/kernel/traps.c +++ b/arch/mips/kernel/traps.c @@ -90,6 +90,7 @@ extern asmlinkage void handle_tr(void); extern asmlinkage void handle_msa_fpe(void); extern asmlinkage void handle_fpe(void); extern asmlinkage void handle_ftlb(void); +extern asmlinkage void handle_gsexc(void); extern asmlinkage void handle_msa(void); extern asmlinkage void handle_mdmx(void); extern asmlinkage void handle_watch(void); @@ -1900,6 +1901,37 @@ asmlinkage void do_ftlb(void) cache_parity_error(); } +asmlinkage void do_gsexc(struct pt_regs *regs, u32 diag1) +{ + u32 exccode = (diag1 & LOONGSON_DIAG1_EXCCODE) >> + LOONGSON_DIAG1_EXCCODE_SHIFT; + enum ctx_state prev_state; + + prev_state = exception_enter(); + + switch (exccode) { + case 0x08: + /* Undocumented exception, will trigger on certain + * also-undocumented instructions accessible from userspace. + * Processor state is not otherwise corrupted, but currently + * we don't know how to proceed. Maybe there is some + * undocumented control flag to enable the instructions? + */ + force_sig(SIGILL); + break; + + default: + /* None of the other exceptions, documented or not, have + * further details given; none are encountered in the wild + * either. Panic in case some of them turn out to be fatal. + */ + show_regs(regs); + panic("Unhandled Loongson exception - GSCause = %08x", diag1); + } + + exception_exit(prev_state); +} + /* * SDBBP EJTAG debug exception handler. * We skip the instruction and return to the next instruction. @@ -2457,6 +2489,9 @@ void __init trap_init(void) if (cpu_has_ftlbparex) set_except_vector(MIPS_EXCCODE_TLBPAR, handle_ftlb); + if (cpu_has_gsexcex) + set_except_vector(LOONGSON_EXCCODE_GSEXC, handle_gsexc); + if (cpu_has_rixiex) { set_except_vector(EXCCODE_TLBRI, tlb_do_page_fault_0); set_except_vector(EXCCODE_TLBXI, tlb_do_page_fault_0); |