[PATCH 5/5] target/ppc: Implement simple monitor mce injection

[Nicholas Piggin <npiggin@gmail.com>]

This enables the mce monitor command for ppc, and adds a spapr
facility to inject machine check exception to a CPU by setting
low level registers.

  (qemu) mce 0 0x200000 0x80 0xdeadbeef 1

    Disabling lock debugging due to kernel taint
    MCE: CPU0: machine check (Severe) Host SLB Multihit [Recovered]
    MCE: CPU0: PID: 495 Comm: a NIP: [0000000130ee07c8]
    MCE: CPU0: Initiator CPU
    MCE: CPU0: Unknown

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 hmp-commands.hx        | 20 +++++++++++++++++++-
 hw/ppc/spapr.c         | 42 ++++++++++++++++++++++++++++++++++++++++++
 include/hw/ppc/spapr.h |  3 +++
 target/ppc/cpu.h       |  3 +++
 target/ppc/monitor.c   | 26 ++++++++++++++++++++++++++
 5 files changed, 93 insertions(+), 1 deletion(-)

diff --git a/hmp-commands.hx b/hmp-commands.hx
index 7f0f3974ad..4a9089b431 100644
--- a/hmp-commands.hx
+++ b/hmp-commands.hx
@@ -1581,12 +1581,30 @@ ERST
         .cmd        = hmp_mce,
     },
 
-#endif
 SRST
 ``mce`` *cpu* *bank* *status* *mcgstatus* *addr* *misc*
   Inject an MCE on the given CPU (x86 only).
 ERST
 
+#endif
+
+#if defined(TARGET_PPC)
+
+    {
+        .name       = "mce",
+        .args_type  = "cpu_index:i,srr1_mask:l,dsisr:i,dar:l,recovered:i",
+        .params     = "cpu srr1_mask dsisr dar recovered",
+        .help       = "inject a MCE on the given CPU",
+        .cmd        = hmp_mce,
+    },
+
+SRST
+``mce`` *cpu* *srr1_mask* *dsisr* *dar* *recovered*
+  Inject an MCE on the given CPU (PPC only).
+ERST
+
+#endif
+
     {
         .name       = "getfd",
         .args_type  = "fdname:s",
diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index 78e649f47d..d83245c438 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -3454,6 +3454,47 @@ static void spapr_nmi(NMIState *n, int cpu_index, Error **errp)
     }
 }
 
+typedef struct MCEInjectionParams {
+    uint64_t srr1_mask;
+    uint32_t dsisr;
+    uint64_t dar;
+    bool recovered;
+} MCEInjectionParams;
+
+static void spapr_do_mce_on_cpu(CPUState *cs, run_on_cpu_data data)
+{
+    MCEInjectionParams *params = data.host_ptr;
+    PowerPCCPU *cpu = POWERPC_CPU(cs);
+    CPUPPCState *env = &cpu->env;
+    uint64_t srr1_mce_bits = PPC_BITMASK(42,45) | PPC_BIT(36); /* POWER9 bits */
+
+    cpu_synchronize_state(cs);
+
+    env->spr[SPR_SRR0] = env->nip;
+    env->spr[SPR_SRR1] = (env->msr & ~srr1_mce_bits) |
+                         (params->srr1_mask & srr1_mce_bits);
+    if (params->dsisr) {
+        env->spr[SPR_DSISR] = params->dsisr;
+        env->spr[SPR_DAR] = params->dar;
+    }
+
+    spapr_mce_req_event(cpu, params->recovered);
+}
+
+static void spapr_cpu_mce_inject(PPCVirtualHypervisor *vhyp, PowerPCCPU *cpu,
+                                 uint64_t srr1_mask, uint32_t dsisr,
+                                 uint64_t dar, bool recovered)
+{
+    CPUState *cs = CPU(cpu);
+    MCEInjectionParams params = {
+        .srr1_mask = srr1_mask,
+        .dsisr = dsisr,
+        .dar = dar,
+        .recovered = recovered,
+    };
+    run_on_cpu(cs, spapr_do_mce_on_cpu, RUN_ON_CPU_HOST_PTR(&params));
+}
+
 int spapr_lmb_dt_populate(SpaprDrc *drc, SpaprMachineState *spapr,
                           void *fdt, int *fdt_start_offset, Error **errp)
 {
@@ -4556,6 +4597,7 @@ static void spapr_machine_class_init(ObjectClass *oc, void *data)
     vhc->encode_hpt_for_kvm_pr = spapr_encode_hpt_for_kvm_pr;
     vhc->cpu_exec_enter = spapr_cpu_exec_enter;
     vhc->cpu_exec_exit = spapr_cpu_exec_exit;
+    vhc->cpu_mce_inject = spapr_cpu_mce_inject;
     xic->ics_get = spapr_ics_get;
     xic->ics_resend = spapr_ics_resend;
     xic->icp_get = spapr_icp_get;
diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
index 42d64a0368..72f86a2ee8 100644
--- a/include/hw/ppc/spapr.h
+++ b/include/hw/ppc/spapr.h
@@ -929,4 +929,7 @@ void spapr_check_pagesize(SpaprMachineState *spapr, hwaddr pagesize,
 
 void spapr_set_all_lpcrs(target_ulong value, target_ulong mask);
 hwaddr spapr_get_rtas_addr(void);
+
+void spapr_mce_inject(CPUState *cs, uint64_t srr1_mask, uint32_t dsisr,
+                      uint64_t dar, bool recovered);
 #endif /* HW_SPAPR_H */
diff --git a/target/ppc/cpu.h b/target/ppc/cpu.h
index f8c7d6f19c..ed8d2015bd 100644
--- a/target/ppc/cpu.h
+++ b/target/ppc/cpu.h
@@ -1189,6 +1189,9 @@ struct PPCVirtualHypervisorClass {
 #ifndef CONFIG_USER_ONLY
     void (*cpu_exec_enter)(PPCVirtualHypervisor *vhyp, PowerPCCPU *cpu);
     void (*cpu_exec_exit)(PPCVirtualHypervisor *vhyp, PowerPCCPU *cpu);
+    void (*cpu_mce_inject)(PPCVirtualHypervisor *vhyp, PowerPCCPU *cpu,
+                           uint64_t srr1_mask, uint32_t dsisr, uint64_t dar,
+                           bool recovered);
 #endif
 };
 
diff --git a/target/ppc/monitor.c b/target/ppc/monitor.c
index a5a177d717..ec997ce673 100644
--- a/target/ppc/monitor.c
+++ b/target/ppc/monitor.c
@@ -28,6 +28,7 @@
 #include "qemu/ctype.h"
 #include "monitor/hmp-target.h"
 #include "monitor/hmp.h"
+#include "qapi/qmp/qdict.h"
 
 static target_long monitor_get_ccr(const struct MonitorDef *md, int val)
 {
@@ -72,6 +73,31 @@ void hmp_info_tlb(Monitor *mon, const QDict *qdict)
     dump_mmu(env1);
 }
 
+void hmp_mce(Monitor *mon, const QDict *qdict)
+{
+    CPUState *cs;
+    int cpu_index = qdict_get_int(qdict, "cpu_index");
+    uint64_t srr1_mask = qdict_get_int(qdict, "srr1_mask");
+    uint32_t dsisr = qdict_get_int(qdict, "dsisr");
+    uint64_t dar = qdict_get_int(qdict, "dar");
+    bool recovered = qdict_get_int(qdict, "recovered");
+
+    cs = qemu_get_cpu(cpu_index);
+
+    if (cs != NULL) {
+        PowerPCCPU *cpu = POWERPC_CPU(cs);
+
+        if (cpu->vhyp) {
+            PPCVirtualHypervisorClass *vhc =
+                PPC_VIRTUAL_HYPERVISOR_GET_CLASS(cpu->vhyp);
+            if (vhc->cpu_mce_inject) {
+                vhc->cpu_mce_inject(cpu->vhyp, cpu,
+                                    srr1_mask, dsisr, dar, recovered);
+            }
+        }
+    }
+}
+
 const MonitorDef monitor_defs[] = {
     { "fpscr", offsetof(CPUPPCState, fpscr) },
     /* Next instruction pointer */
-- 
2.23.0