[Qemu-devel] [PULL v2 1/2] target-alpha: Move alarm to vm_clock

[Richard Henderson <rth@twiddle.net>]

Basing the alarm off the rtc_clock was silly.  It leads to horrible
spinning in the guest after being suspended and resumed, as it tries
to catch up with lost ticks.

This requires adding an accessor for reading the vm_clock too.

Signed-off-by: Richard Henderson <rth@twiddle.net>
---
 hw/alpha/typhoon.c        |  2 +-
 target-alpha/helper.h     |  3 ++-
 target-alpha/sys_helper.c |  7 ++++++-
 target-alpha/translate.c  | 12 ++++++++----
 4 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/hw/alpha/typhoon.c b/hw/alpha/typhoon.c
index 3d7a1cd..b7fb044 100644
--- a/hw/alpha/typhoon.c
+++ b/hw/alpha/typhoon.c
@@ -693,7 +693,7 @@ PCIBus *typhoon_init(ram_addr_t ram_size, ISABus **isa_bus,
         AlphaCPU *cpu = cpus[i];
         s->cchip.cpu[i] = cpu;
         if (cpu != NULL) {
-            cpu->alarm_timer = qemu_new_timer_ns(rtc_clock,
+            cpu->alarm_timer = qemu_new_timer_ns(vm_clock,
                                                  typhoon_alarm_timer,
                                                  (void *)((uintptr_t)s + i));
         }
diff --git a/target-alpha/helper.h b/target-alpha/helper.h
index 3321fde..0e425cf 100644
--- a/target-alpha/helper.h
+++ b/target-alpha/helper.h
@@ -114,7 +114,8 @@ DEF_HELPER_FLAGS_2(tbis, TCG_CALL_NO_RWG, void, env, i64)
 
 DEF_HELPER_1(halt, void, i64);
 
-DEF_HELPER_FLAGS_0(get_time, TCG_CALL_NO_RWG, i64)
+DEF_HELPER_FLAGS_0(get_vmtime, TCG_CALL_NO_RWG, i64)
+DEF_HELPER_FLAGS_0(get_walltime, TCG_CALL_NO_RWG, i64)
 DEF_HELPER_FLAGS_2(set_alarm, TCG_CALL_NO_RWG, void, env, i64)
 #endif
 
diff --git a/target-alpha/sys_helper.c b/target-alpha/sys_helper.c
index 339501a..bd94597 100644
--- a/target-alpha/sys_helper.c
+++ b/target-alpha/sys_helper.c
@@ -70,7 +70,12 @@ void helper_halt(uint64_t restart)
     }
 }
 
-uint64_t helper_get_time(void)
+uint64_t helper_get_vmtime(void)
+{
+    return qemu_get_clock_ns(vm_clock);
+}
+
+uint64_t helper_get_walltime(void)
 {
     return qemu_get_clock_ns(rtc_clock);
 }
diff --git a/target-alpha/translate.c b/target-alpha/translate.c
index dd7f0fb..5558b72 100644
--- a/target-alpha/translate.c
+++ b/target-alpha/translate.c
@@ -1634,15 +1634,19 @@ static ExitStatus gen_mfpr(int ra, int regno)
         return NO_EXIT;
     }
 
-    if (regno == 250) {
-        /* WALL_TIME */
+    /* Special help for VMTIME and WALLTIME.  */
+    if (regno == 250 || regno == 249) {
+	void (*helper)(TCGv) = gen_helper_get_walltime;
+	if (regno == 249) {
+		helper = gen_helper_get_vmtime;
+	}
         if (use_icount) {
             gen_io_start();
-            gen_helper_get_time(cpu_ir[ra]);
+            helper(cpu_ir[ra]);
             gen_io_end();
             return EXIT_PC_STALE;
         } else {
-            gen_helper_get_time(cpu_ir[ra]);
+            helper(cpu_ir[ra]);
             return NO_EXIT;
         }
     }
-- 
1.8.1.4