[PATCH v8 07/10] target/ppc/power8-pmu.c: add PM_RUN_INST_CMPL (0xFA) event

[Daniel Henrique Barboza]

PM_RUN_INST_CMPL, instructions completed with the run latch set, is
the architected PowerISA v3.1 event defined with PMC4SEL = 0xFA.

Implement it by checking for the CTRL RUN bit before incrementing the
counter. To make this work properly we also need to force a new
translation block each time SPR_CTRL is written. A small tweak in
pmu_increment_insns() is then needed to only increment this event
if the thread has the run latch.

Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
---
 target/ppc/cpu.h        |  4 ++++
 target/ppc/cpu_init.c   |  2 +-
 target/ppc/power8-pmu.c | 24 ++++++++++++++++++++++--
 target/ppc/spr_tcg.h    |  1 +
 target/ppc/translate.c  | 12 ++++++++++++
 5 files changed, 40 insertions(+), 3 deletions(-)

diff --git a/target/ppc/cpu.h b/target/ppc/cpu.h
index 38cd2b5c43..993884164f 100644
--- a/target/ppc/cpu.h
+++ b/target/ppc/cpu.h
@@ -304,6 +304,7 @@ typedef enum {
     PMU_EVENT_INACTIVE,
     PMU_EVENT_CYCLES,
     PMU_EVENT_INSTRUCTIONS,
+    PMU_EVENT_INSN_RUN_LATCH,
 } PMUEventType;
 
 /*****************************************************************************/
@@ -389,6 +390,9 @@ typedef enum {
 #define MMCR1_PMC4SEL_START 56
 #define MMCR1_PMC4EVT_EXTR (64 - MMCR1_PMC4SEL_START - MMCR1_EVT_SIZE)
 
+/* PMU uses CTRL_RUN to sample PM_RUN_INST_CMPL */
+#define CTRL_RUN PPC_BIT(63)
+
 /* LPCR bits */
 #define LPCR_VPM0         PPC_BIT(0)
 #define LPCR_VPM1         PPC_BIT(1)
diff --git a/target/ppc/cpu_init.c b/target/ppc/cpu_init.c
index 2d72dde26d..ecce4c7c1e 100644
--- a/target/ppc/cpu_init.c
+++ b/target/ppc/cpu_init.c
@@ -6749,7 +6749,7 @@ static void register_book3s_ctrl_sprs(CPUPPCState *env)
 {
     spr_register(env, SPR_CTRL, "SPR_CTRL",
                  SPR_NOACCESS, SPR_NOACCESS,
-                 SPR_NOACCESS, &spr_write_generic,
+                 SPR_NOACCESS, &spr_write_CTRL,
                  0x00000000);
     spr_register(env, SPR_UCTRL, "SPR_UCTRL",
                  &spr_read_ureg, SPR_NOACCESS,
diff --git a/target/ppc/power8-pmu.c b/target/ppc/power8-pmu.c
index 59d0def79d..98797f0b2f 100644
--- a/target/ppc/power8-pmu.c
+++ b/target/ppc/power8-pmu.c
@@ -96,6 +96,15 @@ static PMUEventType pmc_get_event(CPUPPCState *env, int sprn)
             evt_type = PMU_EVENT_CYCLES;
         }
         break;
+    case 0xFA:
+        /*
+         * PMC4SEL = 0xFA is the "instructions completed
+         * with run latch set" event.
+         */
+        if (sprn == SPR_POWER_PMC4) {
+            evt_type = PMU_EVENT_INSN_RUN_LATCH;
+        }
+        break;
     case 0xFE:
         /*
          * PMC1SEL = 0xFE is the architected PowerISA v3.1
@@ -119,11 +128,22 @@ static bool pmu_increment_insns(CPUPPCState *env, 
uint32_t num_insns)
 
     /* PMC6 never counts instructions */
     for (sprn = SPR_POWER_PMC1; sprn <= SPR_POWER_PMC5; sprn++) {
-        if (pmc_get_event(env, sprn) != PMU_EVENT_INSTRUCTIONS) {
+        PMUEventType evt_type = pmc_get_event(env, sprn);
+        bool insn_event = evt_type == PMU_EVENT_INSTRUCTIONS ||
+                          evt_type == PMU_EVENT_INSN_RUN_LATCH;
+
+        if (pmc_is_inactive(env, sprn) || !insn_event) {
             continue;
         }
 
-        env->spr[sprn] += num_insns;
+        if (evt_type == PMU_EVENT_INSTRUCTIONS) {
+            env->spr[sprn] += num_insns;
+        }
+
+        if (evt_type == PMU_EVENT_INSN_RUN_LATCH &&
+            env->spr[SPR_CTRL] & CTRL_RUN) {
+            env->spr[sprn] += num_insns;
+        }
 
         if (env->spr[sprn] >= PMC_COUNTER_NEGATIVE_VAL &&
             pmc_has_overflow_enabled(env, sprn)) {
diff --git a/target/ppc/spr_tcg.h b/target/ppc/spr_tcg.h
index 1d6521eedc..f98d97c0ba 100644
--- a/target/ppc/spr_tcg.h
+++ b/target/ppc/spr_tcg.h
@@ -28,6 +28,7 @@ void spr_write_generic(DisasContext *ctx, int sprn, int gprn);
 void spr_write_MMCR0(DisasContext *ctx, int sprn, int gprn);
 void spr_write_MMCR1(DisasContext *ctx, int sprn, int gprn);
 void spr_write_PMC(DisasContext *ctx, int sprn, int gprn);
+void spr_write_CTRL(DisasContext *ctx, int sprn, int gprn);
 void spr_read_xer(DisasContext *ctx, int gprn, int sprn);
 void spr_write_xer(DisasContext *ctx, int sprn, int gprn);
 void spr_read_lr(DisasContext *ctx, int gprn, int sprn);
diff --git a/target/ppc/translate.c b/target/ppc/translate.c
index ccc83d0603..d0e361a9d1 100644
--- a/target/ppc/translate.c
+++ b/target/ppc/translate.c
@@ -403,6 +403,18 @@ void spr_write_generic(DisasContext *ctx, int sprn, int 
gprn)
     spr_store_dump_spr(sprn);
 }
 
+void spr_write_CTRL(DisasContext *ctx, int sprn, int gprn)
+{
+    spr_write_generic(ctx, sprn, gprn);
+
+    /*
+     * SPR_CTRL writes must force a new translation block,
+     * allowing the PMU to calculate the run latch events with
+     * more accuracy.
+     */
+    ctx->base.is_jmp = DISAS_EXIT_UPDATE;
+}
+
 #if !defined(CONFIG_USER_ONLY)
 void spr_write_generic32(DisasContext *ctx, int sprn, int gprn)
 {
-- 
2.31.1