Signed-off-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
---
v2:
1) Use rdtime instead of rdcycle for dynamic cpuclk adjustment.
2) Read timeh twice in case of time overflow for 32-bit cpu.
---
include/qemu/timer.h | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)
diff --git a/include/qemu/timer.h b/include/qemu/timer.h
index 9a91cb1248..9a366e551f 100644
--- a/include/qemu/timer.h
+++ b/include/qemu/timer.h
@@ -979,6 +979,28 @@ static inline int64_t cpu_get_host_ticks(void)
return cur - ofs;
}
+#elif defined(__riscv) && __riscv_xlen == 32
+static inline int64_t cpu_get_host_ticks(void)
+{
+ uint32_t lo, hi, tmph;
+ do {
+ asm volatile("RDTIMEH %0\n\t"
+ "RDTIME %1\n\t"
+ "RDTIMEH %2"
+ : "=r"(hi), "=r"(lo), "=r"(tmph));
+ } while (unlikely(tmph != hi));
+ return lo | (uint64_t)hi << 32;
+}
+
+#elif defined(__riscv) && __riscv_xlen > 32
+static inline int64_t cpu_get_host_ticks(void)
+{
+ int64_t val;
+
+ asm volatile("RDTIME %0" : "=r"(val));
+ return val;
+}
+
#else
/* The host CPU doesn't have an easily accessible cycle counter.
Just return a monotonically increasing value. This will be
--
2.17.1