This patch adds support in QEMU to handle "ibm,nmi-register"
and "ibm,nmi-interlock" RTAS calls.
The machine check notification address is saved when the
OS issues "ibm,nmi-register" RTAS call.
This patch also handles the case when multiple processors
experience machine check at or about the same time by
handling "ibm,nmi-interlock" call. In such cases, as per
PAPR, subsequent processors serialize waiting for the first
processor to issue the "ibm,nmi-interlock" call. The second
processor that also received a machine check error waits
till the first processor is done reading the error log.
The first processor issues "ibm,nmi-interlock" call
when the error log is consumed. This patch implements the
releasing part of the error-log while subsequent patch
(which builds error log) handles the locking part.
Signed-off-by: Aravinda Prasad <aravi...@linux.vnet.ibm.com>
---
hw/ppc/spapr.c | 25 +++++++++++++++++++++++++
hw/ppc/spapr_rtas.c | 36 ++++++++++++++++++++++++++++++++++++
include/hw/ppc/spapr.h | 15 ++++++++++++++-
3 files changed, 75 insertions(+), 1 deletion(-)
diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index b6a571b..a533fbe 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -1757,6 +1757,16 @@ static void spapr_machine_reset(void)
first_ppc_cpu->env.gpr[5] = 0;
spapr->cas_reboot = false;
+
+ spapr->mc_reset = 1;
+ spapr->mc_status = -1;
+ spapr->guest_machine_check_addr = -1;
+
+ /* Before destroying, signal vCPUs waiting on this condition */
+ qemu_cond_broadcast(&spapr->mc_delivery_cond);
+ /* It is safe to call destroy as broadcast unblocks all vCPUs */
+ qemu_cond_destroy(&spapr->mc_delivery_cond);
+ qemu_cond_init(&spapr->mc_delivery_cond);
}
static void spapr_create_nvram(sPAPRMachineState *spapr)
@@ -2047,6 +2057,16 @@ static const VMStateDescription vmstate_spapr_dtb = {
},
};
+static const VMStateDescription vmstate_spapr_guest_mc_addr = {
+ .name = "spapr_guest_mc_addr",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT64(guest_machine_check_addr, sPAPRMachineState),
+ VMSTATE_END_OF_LIST()
+ },
+};
+
static const VMStateDescription vmstate_spapr = {
.name = "spapr",
.version_id = 3,
@@ -2077,6 +2097,7 @@ static const VMStateDescription vmstate_spapr = {
&vmstate_spapr_irq_map,
&vmstate_spapr_cap_nested_kvm_hv,
&vmstate_spapr_dtb,
+ &vmstate_spapr_guest_mc_addr,
NULL
}
};
@@ -3021,6 +3042,10 @@ static void spapr_machine_init(MachineState *machine)
kvmppc_spapr_enable_inkernel_multitce();
}
+
+ spapr->mc_status = -1;
+ spapr->mc_reset = 0;
+ qemu_cond_init(&spapr->mc_delivery_cond);
}
static int spapr_kvm_type(const char *vm_type)
diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c
index 7a2cb78..0c2aa0d 100644
--- a/hw/ppc/spapr_rtas.c
+++ b/hw/ppc/spapr_rtas.c
@@ -348,6 +348,38 @@ static void rtas_get_power_level(PowerPCCPU *cpu,
sPAPRMachineState *spapr,
rtas_st(rets, 1, 100);
}
+static void rtas_ibm_nmi_register(PowerPCCPU *cpu,
+ sPAPRMachineState *spapr,
+ uint32_t token, uint32_t nargs,
+ target_ulong args,
+ uint32_t nret, target_ulong rets)
+{
+ spapr->mc_reset = 0;
+ spapr->guest_machine_check_addr = rtas_ld(args, 1);
+ rtas_st(rets, 0, RTAS_OUT_SUCCESS);
+}
+
+static void rtas_ibm_nmi_interlock(PowerPCCPU *cpu,
+ sPAPRMachineState *spapr,
+ uint32_t token, uint32_t nargs,
+ target_ulong args,
+ uint32_t nret, target_ulong rets)
+{
+ if (!spapr->guest_machine_check_addr) {
+ /* NMI register not called */
+ rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
+ } else {
+ /*
+ * VCPU issuing "ibm,nmi-interlock" is done with NMI handling,
+ * hence unset mc_status.
+ */
+ spapr->mc_status = -1;
+ qemu_cond_signal(&spapr->mc_delivery_cond);
+ rtas_st(rets, 0, RTAS_OUT_SUCCESS);
+ }
+}
+
+
static struct rtas_call {
const char *name;
spapr_rtas_fn fn;
@@ -489,6 +521,10 @@ static void core_rtas_register_types(void)
rtas_set_power_level);
spapr_rtas_register(RTAS_GET_POWER_LEVEL, "get-power-level",
rtas_get_power_level);
+ spapr_rtas_register(RTAS_IBM_NMI_REGISTER, "ibm,nmi-register",
+ rtas_ibm_nmi_register);
+ spapr_rtas_register(RTAS_IBM_NMI_INTERLOCK, "ibm,nmi-interlock",
+ rtas_ibm_nmi_interlock);
}
type_init(core_rtas_register_types)
diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
index 59073a7..452f904 100644
--- a/include/hw/ppc/spapr.h
+++ b/include/hw/ppc/spapr.h
@@ -176,6 +176,17 @@ struct sPAPRMachineState {
* occurs during the unplug process. */
QTAILQ_HEAD(, sPAPRDIMMState) pending_dimm_unplugs;
+ /* State related to "ibm,nmi-register" and "ibm,nmi-interlock" calls */
+ target_ulong guest_machine_check_addr;
+ /*
+ * mc_status is set to -1 if mc is not in progress, else is set to the CPU
+ * handling the mc.
+ */
+ int mc_status;
+ /* mc_reset is set to 1 if machine reset is in progress */
+ bool mc_reset;
+ QemuCond mc_delivery_cond;
+
/*< public >*/
char *kvm_type;
char *host_model;
@@ -608,8 +619,10 @@ target_ulong spapr_hypercall(PowerPCCPU *cpu, target_ulong
opcode,
#define RTAS_IBM_CREATE_PE_DMA_WINDOW (RTAS_TOKEN_BASE + 0x27)
#define RTAS_IBM_REMOVE_PE_DMA_WINDOW (RTAS_TOKEN_BASE + 0x28)
#define RTAS_IBM_RESET_PE_DMA_WINDOW (RTAS_TOKEN_BASE + 0x29)
+#define RTAS_IBM_NMI_REGISTER (RTAS_TOKEN_BASE + 0x2A)
+#define RTAS_IBM_NMI_INTERLOCK (RTAS_TOKEN_BASE + 0x2B)
-#define RTAS_TOKEN_MAX (RTAS_TOKEN_BASE + 0x2A)
+#define RTAS_TOKEN_MAX (RTAS_TOKEN_BASE + 0x2C)
/* RTAS ibm,get-system-parameter token values */
#define RTAS_SYSPARM_SPLPAR_CHARACTERISTICS 20
