diff options
Diffstat (limited to 'arch/mips/kernel/traps.c')
| -rw-r--r-- | arch/mips/kernel/traps.c | 31 |
1 files changed, 25 insertions, 6 deletions
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c index fcae66752972..79cf7e913b99 100644 --- a/arch/mips/kernel/traps.c +++ b/arch/mips/kernel/traps.c @@ -534,8 +534,7 @@ static int simulate_llsc(struct pt_regs *regs, unsigned int opcode) /* * Simulate trapping 'rdhwr' instructions to provide user accessible - * registers not implemented in hardware. The only current use of this - * is the thread area pointer. + * registers not implemented in hardware. */ static int simulate_rdhwr(struct pt_regs *regs, unsigned int opcode) { @@ -545,11 +544,31 @@ static int simulate_rdhwr(struct pt_regs *regs, unsigned int opcode) int rd = (opcode & RD) >> 11; int rt = (opcode & RT) >> 16; switch (rd) { - case 29: - regs->regs[rt] = ti->tp_value; - return 0; + case 0: /* CPU number */ + regs->regs[rt] = smp_processor_id(); + return 0; + case 1: /* SYNCI length */ + regs->regs[rt] = min(current_cpu_data.dcache.linesz, + current_cpu_data.icache.linesz); + return 0; + case 2: /* Read count register */ + regs->regs[rt] = read_c0_count(); + return 0; + case 3: /* Count register resolution */ + switch (current_cpu_data.cputype) { + case CPU_20KC: + case CPU_25KF: + regs->regs[rt] = 1; + break; default: - return -1; + regs->regs[rt] = 2; + } + return 0; + case 29: + regs->regs[rt] = ti->tp_value; + return 0; + default: + return -1; } } |