[PATCH v3 06/15] target/ppc/power8_pmu.c: add PM_RUN_INST_CMPL (0xFA) event

[Daniel Henrique Barboza <danielhb413@gmail.com>]

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.

Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
---
 target/ppc/cpu.h        |  3 +++
 target/ppc/cpu_init.c   |  2 +-
 target/ppc/power8_pmu.c | 27 ++++++++++++++++++++-------
 target/ppc/spr_tcg.h    |  1 +
 target/ppc/translate.c  | 12 ++++++++++++
 5 files changed, 37 insertions(+), 8 deletions(-)

diff --git a/target/ppc/cpu.h b/target/ppc/cpu.h
index 4d4886ac74..76b462c3c8 100644
--- a/target/ppc/cpu.h
+++ b/target/ppc/cpu.h
@@ -363,6 +363,9 @@ typedef struct ppc_v3_pate_t {
 #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 07c79745ba..0013cba5ff 100644
--- a/target/ppc/cpu_init.c
+++ b/target/ppc/cpu_init.c
@@ -6748,7 +6748,7 @@ 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 9769c0ff35..f584480fde 100644
--- a/target/ppc/power8_pmu.c
+++ b/target/ppc/power8_pmu.c
@@ -133,17 +133,15 @@ void helper_store_mmcr0(CPUPPCState *env, target_ulong value)
     }
 }
 
-static bool pmc_counting_insns(CPUPPCState *env, int sprn)
+static bool pmc_counting_insns(CPUPPCState *env, int sprn,
+                               uint8_t event)
 {
     bool ret = false;
-    uint8_t event;
 
     if (sprn == SPR_POWER_PMC5) {
         return true;
     }
 
-    event = get_PMC_event(env, sprn);
-
     /*
      * Event 0x2 is an implementation-dependent event that IBM
      * POWER chips implement (at least since POWER8) that is
@@ -158,8 +156,15 @@ static bool pmc_counting_insns(CPUPPCState *env, int sprn)
         return event == 0x2 || event == 0xFE;
     case SPR_POWER_PMC2:
     case SPR_POWER_PMC3:
-    case SPR_POWER_PMC4:
         return event == 0x2;
+    case SPR_POWER_PMC4:
+        /*
+         * Event 0xFA is the "instructions completed with run latch
+         * set" event. Consider it as instruction counting event.
+         * The caller is responsible for handling it separately
+         * from PM_INST_CMPL.
+         */
+        return event == 0x2 || event == 0xFA;
     default:
         break;
     }
@@ -173,8 +178,16 @@ void helper_insns_inc(CPUPPCState *env, uint32_t num_insns)
     int sprn;
 
     for (sprn = SPR_POWER_PMC1; sprn <= SPR_POWER_PMC5; sprn++) {
-        if (pmc_counting_insns(env, sprn)) {
-            env->spr[sprn] += num_insns;
+        uint8_t event = get_PMC_event(env, sprn);
+
+        if (pmc_counting_insns(env, sprn, event)) {
+            if (sprn == SPR_POWER_PMC4 && event == 0xFA) {
+                if (env->spr[SPR_CTRL] & CTRL_RUN) {
+                    env->spr[SPR_POWER_PMC4] += num_insns;
+                }
+            } else {
+                env->spr[sprn] += num_insns;
+            }
         }
     }
 }
diff --git a/target/ppc/spr_tcg.h b/target/ppc/spr_tcg.h
index 51fbc081de..5e6ed36eb1 100644
--- a/target/ppc/spr_tcg.h
+++ b/target/ppc/spr_tcg.h
@@ -26,6 +26,7 @@ void spr_noaccess(DisasContext *ctx, int gprn, int sprn);
 void spr_read_generic(DisasContext *ctx, int gprn, int sprn);
 void spr_write_generic(DisasContext *ctx, int sprn, int gprn);
 void spr_write_MMCR0(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 b7235a2be0..866b1d2b34 100644
--- a/target/ppc/translate.c
+++ b/target/ppc/translate.c
@@ -402,6 +402,18 @@ 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);
+
+    /*
+     * Write in SPR_CTRL 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(TARGET_PPC64) && !defined(CONFIG_USER_ONLY)
 void spr_write_MMCR0(DisasContext *ctx, int sprn, int gprn)
 {
-- 
2.31.1