diff options
| -rw-r--r-- | arch/powerpc/include/asm/hmi.h | 4 | ||||
| -rw-r--r-- | arch/powerpc/include/asm/reg.h | 5 | ||||
| -rw-r--r-- | arch/powerpc/kernel/mce.c | 142 | ||||
| -rw-r--r-- | arch/powerpc/kvm/book3s_hv_ras.c | 8 | ||||
| -rw-r--r-- | arch/powerpc/kvm/book3s_hv_rmhandlers.S | 9 |
5 files changed, 131 insertions, 37 deletions
diff --git a/arch/powerpc/include/asm/hmi.h b/arch/powerpc/include/asm/hmi.h index 85b7a1a21e22..9c14f7b5c46c 100644 --- a/arch/powerpc/include/asm/hmi.h +++ b/arch/powerpc/include/asm/hmi.h @@ -42,4 +42,8 @@ extern void wait_for_tb_resync(void); static inline void wait_for_subcore_guest_exit(void) { } static inline void wait_for_tb_resync(void) { } #endif + +struct pt_regs; +extern long hmi_handle_debugtrig(struct pt_regs *regs); + #endif /* __ASM_PPC64_HMI_H__ */ diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h index b779f3ccd412..14e41b843952 100644 --- a/arch/powerpc/include/asm/reg.h +++ b/arch/powerpc/include/asm/reg.h @@ -432,8 +432,9 @@ #define SPRN_LPID 0x13F /* Logical Partition Identifier */ #endif #define LPID_RSVD 0x3ff /* Reserved LPID for partn switching */ -#define SPRN_HMER 0x150 /* Hardware m? error recovery */ -#define SPRN_HMEER 0x151 /* Hardware m? enable error recovery */ +#define SPRN_HMER 0x150 /* Hypervisor maintenance exception reg */ +#define HMER_DEBUG_TRIG (1ul << (63 - 17)) /* Debug trigger */ +#define SPRN_HMEER 0x151 /* Hyp maintenance exception enable reg */ #define SPRN_PCR 0x152 /* Processor compatibility register */ #define PCR_VEC_DIS (1ul << (63-0)) /* Vec. disable (bit NA since POWER8) */ #define PCR_VSX_DIS (1ul << (63-1)) /* VSX disable (bit NA since POWER8) */ diff --git a/arch/powerpc/kernel/mce.c b/arch/powerpc/kernel/mce.c index 742e4658c5dc..d2fecaec4fec 100644 --- a/arch/powerpc/kernel/mce.c +++ b/arch/powerpc/kernel/mce.c @@ -495,37 +495,123 @@ long machine_check_early(struct pt_regs *regs) return handled; } -long hmi_exception_realmode(struct pt_regs *regs) +/* Possible meanings for HMER_DEBUG_TRIG bit being set on POWER9 */ +static enum { + DTRIG_UNKNOWN, + DTRIG_VECTOR_CI, /* need to emulate vector CI load instr */ + DTRIG_SUSPEND_ESCAPE, /* need to escape from TM suspend mode */ +} hmer_debug_trig_function; + +static int init_debug_trig_function(void) { - __this_cpu_inc(irq_stat.hmi_exceptions); - -#ifdef CONFIG_PPC_BOOK3S_64 - /* Workaround for P9 vector CI loads (see p9_hmi_special_emu) */ - if (pvr_version_is(PVR_POWER9)) { - unsigned long hmer = mfspr(SPRN_HMER); - - /* Do we have the debug bit set */ - if (hmer & PPC_BIT(17)) { - hmer &= ~PPC_BIT(17); - mtspr(SPRN_HMER, hmer); - - /* - * Now to avoid problems with soft-disable we - * only do the emulation if we are coming from - * user space - */ - if (user_mode(regs)) - local_paca->hmi_p9_special_emu = 1; - - /* - * Don't bother going to OPAL if that's the - * only relevant bit. - */ - if (!(hmer & mfspr(SPRN_HMEER))) - return local_paca->hmi_p9_special_emu; + int pvr; + struct device_node *cpun; + struct property *prop = NULL; + const char *str; + + /* First look in the device tree */ + preempt_disable(); + cpun = of_get_cpu_node(smp_processor_id(), NULL); + if (cpun) { + of_property_for_each_string(cpun, "ibm,hmi-special-triggers", + prop, str) { + if (strcmp(str, "bit17-vector-ci-load") == 0) + hmer_debug_trig_function = DTRIG_VECTOR_CI; + else if (strcmp(str, "bit17-tm-suspend-escape") == 0) + hmer_debug_trig_function = DTRIG_SUSPEND_ESCAPE; } + of_node_put(cpun); + } + preempt_enable(); + + /* If we found the property, don't look at PVR */ + if (prop) + goto out; + + pvr = mfspr(SPRN_PVR); + /* Check for POWER9 Nimbus (scale-out) */ + if ((PVR_VER(pvr) == PVR_POWER9) && (pvr & 0xe000) == 0) { + /* DD2.2 and later */ + if ((pvr & 0xfff) >= 0x202) + hmer_debug_trig_function = DTRIG_SUSPEND_ESCAPE; + /* DD2.0 and DD2.1 - used for vector CI load emulation */ + else if ((pvr & 0xfff) >= 0x200) + hmer_debug_trig_function = DTRIG_VECTOR_CI; + } + + out: + switch (hmer_debug_trig_function) { + case DTRIG_VECTOR_CI: + pr_debug("HMI debug trigger used for vector CI load\n"); + break; + case DTRIG_SUSPEND_ESCAPE: + pr_debug("HMI debug trigger used for TM suspend escape\n"); + break; + default: + break; } -#endif /* CONFIG_PPC_BOOK3S_64 */ + return 0; +} +__initcall(init_debug_trig_function); + +/* + * Handle HMIs that occur as a result of a debug trigger. + * Return values: + * -1 means this is not a HMI cause that we know about + * 0 means no further handling is required + * 1 means further handling is required + */ +long hmi_handle_debugtrig(struct pt_regs *regs) +{ + unsigned long hmer = mfspr(SPRN_HMER); + long ret = 0; + + /* HMER_DEBUG_TRIG bit is used for various workarounds on P9 */ + if (!((hmer & HMER_DEBUG_TRIG) + && hmer_debug_trig_function != DTRIG_UNKNOWN)) + return -1; + + hmer &= ~HMER_DEBUG_TRIG; + /* HMER is a write-AND register */ + mtspr(SPRN_HMER, ~HMER_DEBUG_TRIG); + + switch (hmer_debug_trig_function) { + case DTRIG_VECTOR_CI: + /* + * Now to avoid problems with soft-disable we + * only do the emulation if we are coming from + * host user space + */ + if (regs && user_mode(regs)) + ret = local_paca->hmi_p9_special_emu = 1; + + break; + + default: + break; + } + + /* + * See if any other HMI causes remain to be handled + */ + if (hmer & mfspr(SPRN_HMEER)) + return -1; + + return ret; +} + +/* + * Return values: + */ +long hmi_exception_realmode(struct pt_regs *regs) +{ + int ret; + + __this_cpu_inc(irq_stat.hmi_exceptions); + + ret = hmi_handle_debugtrig(regs); + if (ret >= 0) + return ret; wait_for_subcore_guest_exit(); diff --git a/arch/powerpc/kvm/book3s_hv_ras.c b/arch/powerpc/kvm/book3s_hv_ras.c index c356f9a40b24..c296343d0dcc 100644 --- a/arch/powerpc/kvm/book3s_hv_ras.c +++ b/arch/powerpc/kvm/book3s_hv_ras.c @@ -268,17 +268,19 @@ static void kvmppc_tb_resync_done(void) * secondary threads to proceed. * - All secondary threads will eventually call opal hmi handler on * their exit path. + * + * Returns 1 if the timebase offset should be applied, 0 if not. */ long kvmppc_realmode_hmi_handler(void) { - int ptid = local_paca->kvm_hstate.ptid; bool resync_req; - /* This is only called on primary thread. */ - BUG_ON(ptid != 0); __this_cpu_inc(irq_stat.hmi_exceptions); + if (hmi_handle_debugtrig(NULL) >= 0) + return 1; + /* * By now primary thread has already completed guest->host * partition switch but haven't signaled secondaries yet. diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S index 2659844784b8..bd0b623335af 100644 --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S @@ -1909,16 +1909,17 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S) bne 27f bl kvmppc_realmode_hmi_handler nop + cmpdi r3, 0 li r12, BOOK3S_INTERRUPT_HMI /* - * At this point kvmppc_realmode_hmi_handler would have resync-ed - * the TB. Hence it is not required to subtract guest timebase - * offset from timebase. So, skip it. + * At this point kvmppc_realmode_hmi_handler may have resync-ed + * the TB, and if it has, we must not subtract the guest timebase + * offset from the timebase. So, skip it. * * Also, do not call kvmppc_subcore_exit_guest() because it has * been invoked as part of kvmppc_realmode_hmi_handler(). */ - b 30f + beq 30f 27: /* Subtract timebase offset from timebase */ |