target/ppc: Implement watchpoint debug facility for v2.07S

ISA v2.07S introduced the watchpoint facility based on the DAWR0
and DAWRX0 SPRs. Implement this in TCG.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>

1 files changed, 59 insertions, 0 deletions

diff --git a/target/ppc/cpu.c b/target/ppc/cpu.c
index d9c665ce18..62e1c15e3d 100644
--- a/target/ppc/cpu.c
+++ b/target/ppc/cpu.c
@@ -128,6 +128,65 @@ void ppc_store_ciabr(CPUPPCState *env, target_ulong val)
     env->spr[SPR_CIABR] = val;
     ppc_update_ciabr(env);
 }
+
+void ppc_update_daw0(CPUPPCState *env)
+{
+    CPUState *cs = env_cpu(env);
+    target_ulong deaw = env->spr[SPR_DAWR0] & PPC_BITMASK(0, 60);
+    uint32_t dawrx = env->spr[SPR_DAWRX0];
+    int mrd = extract32(dawrx, PPC_BIT_NR(48), 54 - 48);
+    bool dw = extract32(dawrx, PPC_BIT_NR(57), 1);
+    bool dr = extract32(dawrx, PPC_BIT_NR(58), 1);
+    bool hv = extract32(dawrx, PPC_BIT_NR(61), 1);
+    bool sv = extract32(dawrx, PPC_BIT_NR(62), 1);
+    bool pr = extract32(dawrx, PPC_BIT_NR(62), 1);
+    vaddr len;
+    int flags;
+
+    if (env->dawr0_watchpoint) {
+        cpu_watchpoint_remove_by_ref(cs, env->dawr0_watchpoint);
+        env->dawr0_watchpoint = NULL;
+    }
+
+    if (!dr && !dw) {
+        return;
+    }
+
+    if (!hv && !sv && !pr) {
+        return;
+    }
+
+    len = (mrd + 1) * 8;
+    flags = BP_CPU | BP_STOP_BEFORE_ACCESS;
+    if (dr) {
+        flags |= BP_MEM_READ;
+    }
+    if (dw) {
+        flags |= BP_MEM_WRITE;
+    }
+
+    cpu_watchpoint_insert(cs, deaw, len, flags, &env->dawr0_watchpoint);
+}
+
+void ppc_store_dawr0(CPUPPCState *env, target_ulong val)
+{
+    env->spr[SPR_DAWR0] = val;
+    ppc_update_daw0(env);
+}
+
+void ppc_store_dawrx0(CPUPPCState *env, uint32_t val)
+{
+    int hrammc = extract32(val, PPC_BIT_NR(56), 1);
+
+    if (hrammc) {
+        /* This might be done with a second watchpoint at the xor of DEAW[0] */
+        qemu_log_mask(LOG_UNIMP, "%s: DAWRX0[HRAMMC] is unimplemented\n",
+                      __func__);
+    }
+
+    env->spr[SPR_DAWRX0] = val;
+    ppc_update_daw0(env);
+}
 #endif
 #endif