diff options
Diffstat (limited to 'arch/powerpc/kernel/traps.c')
| -rw-r--r-- | arch/powerpc/kernel/traps.c | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 9b352bd0a460..d9f10f2fc372 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -598,6 +598,9 @@ static void parse_fpe(struct pt_regs *regs) #define INST_STSWI 0x7c0005aa #define INST_STSWX 0x7c00052a +#define INST_POPCNTB 0x7c0000f4 +#define INST_POPCNTB_MASK 0xfc0007fe + static int emulate_string_inst(struct pt_regs *regs, u32 instword) { u8 rT = (instword >> 21) & 0x1f; @@ -666,6 +669,23 @@ static int emulate_string_inst(struct pt_regs *regs, u32 instword) return 0; } +static int emulate_popcntb_inst(struct pt_regs *regs, u32 instword) +{ + u32 ra,rs; + unsigned long tmp; + + ra = (instword >> 16) & 0x1f; + rs = (instword >> 21) & 0x1f; + + tmp = regs->gpr[rs]; + tmp = tmp - ((tmp >> 1) & 0x5555555555555555ULL); + tmp = (tmp & 0x3333333333333333ULL) + ((tmp >> 2) & 0x3333333333333333ULL); + tmp = (tmp + (tmp >> 4)) & 0x0f0f0f0f0f0f0f0fULL; + regs->gpr[ra] = tmp; + + return 0; +} + static int emulate_instruction(struct pt_regs *regs) { u32 instword; @@ -703,6 +723,11 @@ static int emulate_instruction(struct pt_regs *regs) if ((instword & INST_STRING_GEN_MASK) == INST_STRING) return emulate_string_inst(regs, instword); + /* Emulate the popcntb (Population Count Bytes) instruction. */ + if ((instword & INST_POPCNTB_MASK) == INST_POPCNTB) { + return emulate_popcntb_inst(regs, instword); + } + return -EINVAL; } |