diff options
-rw-r--r-- | target-alpha/op_helper.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/target-alpha/op_helper.c b/target-alpha/op_helper.c index 91ef90a07c..36b82899d0 100644 --- a/target-alpha/op_helper.c +++ b/target-alpha/op_helper.c @@ -65,8 +65,17 @@ static void QEMU_NORETURN arith_excp(int exc, uint64_t mask) uint64_t helper_load_pcc (void) { - /* ??? This isn't a timer for which we have any rate info. */ +#ifndef CONFIG_USER_ONLY + /* In system mode we have access to a decent high-resolution clock. + In order to make OS-level time accounting work with the RPCC, + present it with a well-timed clock fixed at 250MHz. */ + return (((uint64_t)env->pcc_ofs << 32) + | (uint32_t)(qemu_get_clock_ns(vm_clock) >> 2)); +#else + /* In user-mode, vm_clock doesn't exist. Just pass through the host cpu + clock ticks. Also, don't bother taking PCC_OFS into account. */ return (uint32_t)cpu_get_real_ticks(); +#endif } uint64_t helper_load_fpcr (void) |