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. Signed-off-by: Aravinda Prasad <aravi...@linux.vnet.ibm.com> --- hw/ppc/spapr.c | 9 ++++++++ hw/ppc/spapr_rtas.c | 57 ++++++++++++++++++++++++++++++++++++++++++++++++ include/hw/ppc/spapr.h | 5 +++- 3 files changed, 70 insertions(+), 1 deletion(-) diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index 9f2e5d2..6992b32 100644 --- a/hw/ppc/spapr.c +++ b/hw/ppc/spapr.c @@ -2941,6 +2941,15 @@ static void spapr_machine_init(MachineState *machine) /* Resize rtas blob to accommodate error log */ spapr->rtas_size = RTAS_ERROR_LOG_MAX; + + /* Set fwnmi capability in KVM */ + if (kvmppc_set_fwnmi() < 0) { + error_report("Could not enable FWNMI capability"); + exit(1); + } + + /* Register ibm,nmi-register and ibm,nmi-interlock RTAS calls */ + spapr_fwnmi_register(); } spapr->rtas_blob = g_malloc(spapr->rtas_size); diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c index d8fb8a8..b569538 100644 --- a/hw/ppc/spapr_rtas.c +++ b/hw/ppc/spapr_rtas.c @@ -400,6 +400,55 @@ 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) +{ + hwaddr rtas_addr = spapr_get_rtas_addr(); + + if (!rtas_addr) { + rtas_st(rets, 0, RTAS_OUT_NOT_SUPPORTED); + return; + } + + if (spapr_get_cap(spapr, SPAPR_CAP_FWNMI_MCE) == SPAPR_CAP_OFF) { + rtas_st(rets, 0, RTAS_OUT_NOT_SUPPORTED); + return; + } + + 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 == -1) { + /* NMI register not called */ + rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR); + return; + } + + if (spapr->mc_status != cpu->vcpu_id) { + /* The vCPU that hit the NMI should invoke "ibm,nmi-interlock" */ + rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR); + return; + } + + /* + * 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; @@ -544,6 +593,14 @@ hwaddr spapr_get_rtas_addr(void) return (hwaddr)fdt32_to_cpu(*rtas_data); } +void spapr_fwnmi_register(void) +{ + 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); +} + static void core_rtas_register_types(void) { spapr_rtas_register(RTAS_DISPLAY_CHARACTER, "display-character", diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h index ffefde7..dada821 100644 --- a/include/hw/ppc/spapr.h +++ b/include/hw/ppc/spapr.h @@ -655,8 +655,10 @@ target_ulong spapr_hypercall(PowerPCCPU *cpu, target_ulong opcode, #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_SUSPEND_ME (RTAS_TOKEN_BASE + 0x2A) +#define RTAS_IBM_NMI_REGISTER (RTAS_TOKEN_BASE + 0x2B) +#define RTAS_IBM_NMI_INTERLOCK (RTAS_TOKEN_BASE + 0x2C) -#define RTAS_TOKEN_MAX (RTAS_TOKEN_BASE + 0x2B) +#define RTAS_TOKEN_MAX (RTAS_TOKEN_BASE + 0x2D) /* RTAS ibm,get-system-parameter token values */ #define RTAS_SYSPARM_SPLPAR_CHARACTERISTICS 20 @@ -908,4 +910,5 @@ 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_fwnmi_register(void); #endif /* HW_SPAPR_H */