[PATCH 3/9] ppc: allow the hdecr timer to be created/destroyed

[Nicholas Piggin <npiggin@gmail.com>]

Machines which don't emulate the HDEC facility are able to use the
timer for something else. Provide functions to start and stop the
hdecr timer.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 hw/ppc/ppc.c         | 20 ++++++++++++++++++++
 include/hw/ppc/ppc.h |  3 +++
 2 files changed, 23 insertions(+)

diff --git a/hw/ppc/ppc.c b/hw/ppc/ppc.c
index c6dfc5975f..4bfd413c7f 100644
--- a/hw/ppc/ppc.c
+++ b/hw/ppc/ppc.c
@@ -1083,6 +1083,26 @@ clk_setup_cb cpu_ppc_tb_init (CPUPPCState *env, uint32_t freq)
     return &cpu_ppc_set_tb_clk;
 }
 
+void cpu_ppc_hdecr_init (CPUPPCState *env)
+{
+    PowerPCCPU *cpu = env_archcpu(env);
+
+    assert(env->tb_env->hdecr_timer == NULL);
+
+    env->tb_env->hdecr_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, &cpu_ppc_hdecr_cb,
+                                                 cpu);
+}
+
+void cpu_ppc_hdecr_exit (CPUPPCState *env)
+{
+    PowerPCCPU *cpu = env_archcpu(env);
+
+    timer_free(env->tb_env->hdecr_timer);
+    env->tb_env->hdecr_timer = NULL;
+
+    cpu_ppc_hdecr_lower(cpu);
+}
+
 /*****************************************************************************/
 /* PowerPC 40x timers */
 
diff --git a/include/hw/ppc/ppc.h b/include/hw/ppc/ppc.h
index 93e614cffd..fcf9e495a0 100644
--- a/include/hw/ppc/ppc.h
+++ b/include/hw/ppc/ppc.h
@@ -54,6 +54,9 @@ struct ppc_tb_t {
 
 uint64_t cpu_ppc_get_tb(ppc_tb_t *tb_env, uint64_t vmclk, int64_t tb_offset);
 clk_setup_cb cpu_ppc_tb_init (CPUPPCState *env, uint32_t freq);
+void cpu_ppc_hdecr_init (CPUPPCState *env);
+void cpu_ppc_hdecr_exit (CPUPPCState *env);
+
 /* Embedded PowerPC DCR management */
 typedef uint32_t (*dcr_read_cb)(void *opaque, int dcrn);
 typedef void (*dcr_write_cb)(void *opaque, int dcrn, uint32_t val);
-- 
2.23.0