This patch adds FWNMI support in qemu for powerKVM guests by handling the ibm,nmi-register rtas call. Whenever OS issues ibm,nmi-register RTAS call, the machine check notification address is saved and the machine check interrupt vector 0x200 is patched to issue a private hcall.
Signed-off-by: Aravinda Prasad <aravi...@linux.vnet.ibm.com> --- hw/ppc/spapr_rtas.c | 91 ++++++++++++++++++++++++++++++++++++++++++++++++ include/hw/ppc/spapr.h | 8 ++++ 2 files changed, 98 insertions(+), 1 deletion(-) diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c index 02ddbf9..1135d2b 100644 --- a/hw/ppc/spapr_rtas.c +++ b/hw/ppc/spapr_rtas.c @@ -277,6 +277,91 @@ static void rtas_ibm_set_system_parameter(PowerPCCPU *cpu, rtas_st(rets, 0, ret); } +static void rtas_ibm_nmi_register(PowerPCCPU *cpu, + sPAPREnvironment *spapr, + uint32_t token, uint32_t nargs, + target_ulong args, + uint32_t nret, target_ulong rets) +{ + int i; + uint32_t branch_inst = 0x48000002; + target_ulong guest_machine_check_addr; + PowerPCCPUClass *pcc = POWERPC_CPU_GET_CLASS(cpu); + /* + * Trampoline saves r3 in sprg2 and issues private hcall + * to request qemu to build error log. QEMU builds the + * error log, copies to rtas-blob and returns the address. + * The initial 16 bytes in rtas-blob consists of saved srr0 + * and srr1 which we restore and pass on the actual error + * log address to OS handled mcachine check notification + * routine + */ + uint32_t trampoline[] = { + 0x7c7243a6, /* mtspr SPRN_SPRG2,r3 */ + 0x38600000, /* li r3,0 */ + /* 0xf004 is the KVMPPC_H_REPORT_ERR private HCALL */ + 0x6063f004, /* ori r3,r3,f004 */ + /* Issue H_CALL */ + 0x44000022, /* sc 1 */ + 0x7c9243a6, /* mtspr r4 sprg2 */ + 0xe8830000, /* ld r4, 0(r3) */ + 0x7c9a03a6, /* mtspr r4, srr0 */ + 0xe8830008, /* ld r4, 8(r3) */ + 0x7c9b03a6, /* mtspr r4, srr1 */ + 0x38630010, /* addi r3,r3,16 */ + 0x7c9242a6, /* mfspr r4 sprg2 */ + 0x48000002, /* Branch to address registered + * by OS. The branch address is + * patched below */ + 0x48000000, /* b . */ + }; + int total_inst = sizeof(trampoline) / sizeof(uint32_t); + + /* Store the system reset and machine check address */ + guest_machine_check_addr = rtas_ld(args, 1); + + /* Safety Check */ + if (sizeof(trampoline) >= MC_INTERRUPT_VECTOR_SIZE) { + fprintf(stderr, "Unable to register ibm,nmi_register: " + "Trampoline size exceeded\n"); + rtas_st(rets, 0, RTAS_OUT_NOT_SUPPORTED); + return; + } + + /* + * Update the branch instruction in trampoline with the absolute + * machine check address requested by OS + */ + branch_inst |= guest_machine_check_addr; + memcpy(&trampoline[11], &branch_inst, sizeof(branch_inst)); + + /* Handle all Host/Guest LE/BE combinations */ + if ((*pcc->interrupts_big_endian)(cpu)) { + for (i = 0; i < total_inst; i++) { + trampoline[i] = cpu_to_be32(trampoline[i]); + } + } else { + for (i = 0; i < total_inst; i++) { + trampoline[i] = cpu_to_le32(trampoline[i]); + } + } + + /* Patch 0x200 NMI interrupt vector memory area of guest */ + cpu_physical_memory_write(MC_INTERRUPT_VECTOR, trampoline, + sizeof(trampoline)); + + rtas_st(rets, 0, RTAS_OUT_SUCCESS); +} + +static void rtas_ibm_nmi_interlock(PowerPCCPU *cpu, + sPAPREnvironment *spapr, + uint32_t token, uint32_t nargs, + target_ulong args, + uint32_t nret, target_ulong rets) +{ + rtas_st(rets, 0, RTAS_OUT_SUCCESS); +} + static struct rtas_call { const char *name; spapr_rtas_fn fn; @@ -404,6 +489,12 @@ static void core_rtas_register_types(void) spapr_rtas_register(RTAS_IBM_SET_SYSTEM_PARAMETER, "ibm,set-system-parameter", rtas_ibm_set_system_parameter); + 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 57199f5..8c854ca 100644 --- a/include/hw/ppc/spapr.h +++ b/include/hw/ppc/spapr.h @@ -386,8 +386,10 @@ int spapr_allocate_irq_block(int num, bool lsi, bool msi); #define RTAS_IBM_CONFIGURE_CONNECTOR (RTAS_TOKEN_BASE + 0x1E) #define RTAS_IBM_OS_TERM (RTAS_TOKEN_BASE + 0x1F) #define RTAS_IBM_EXTENDED_OS_TERM (RTAS_TOKEN_BASE + 0x20) +#define RTAS_IBM_NMI_REGISTER (RTAS_TOKEN_BASE + 0x21) +#define RTAS_IBM_NMI_INTERLOCK (RTAS_TOKEN_BASE + 0x22) -#define RTAS_TOKEN_MAX (RTAS_TOKEN_BASE + 0x21) +#define RTAS_TOKEN_MAX (RTAS_TOKEN_BASE + 0x23) /* RTAS ibm,get-system-parameter token values */ #define RTAS_SYSPARM_SPLPAR_CHARACTERISTICS 20 @@ -485,4 +487,8 @@ int spapr_dma_dt(void *fdt, int node_off, const char *propname, int spapr_tcet_dma_dt(void *fdt, int node_off, const char *propname, sPAPRTCETable *tcet); +/* Machine Check Interrupt related macros */ +#define MC_INTERRUPT_VECTOR 0x200 +#define MC_INTERRUPT_VECTOR_SIZE 0x100 + #endif /* !defined (__HW_SPAPR_H__) */