diff --git a/arch/powerpc/include/asm/machdep.h b/arch/powerpc/include/asm/machdep.h index ad3025d0880b1c709d073e9d42f55a71a9a8159a..4da6574e9a204c50cb682c87ddf6a0392740cbd2 100644 --- a/arch/powerpc/include/asm/machdep.h +++ b/arch/powerpc/include/asm/machdep.h @@ -170,6 +170,9 @@ struct machdep_calls { int (*system_reset_exception)(struct pt_regs *regs); int (*machine_check_exception)(struct pt_regs *regs); + /* Called during machine check exception to retrive fixup address. */ + bool (*mce_check_early_recovery)(struct pt_regs *regs); + /* Motherboard/chipset features. This is a kind of general purpose * hook used to control some machine specific features (like reset * lines, chip power control, etc...). diff --git a/arch/powerpc/include/asm/mce.h b/arch/powerpc/include/asm/mce.h index 8e99edf6d966d8129a7c1e3feef84334fba2b250..f97d8cb6bdf64fd8e147035d659b71016c33ecd0 100644 --- a/arch/powerpc/include/asm/mce.h +++ b/arch/powerpc/include/asm/mce.h @@ -187,7 +187,8 @@ struct mce_error_info { #define MCE_EVENT_DONTRELEASE false extern void save_mce_event(struct pt_regs *regs, long handled, - struct mce_error_info *mce_err, uint64_t addr); + struct mce_error_info *mce_err, uint64_t nip, + uint64_t addr); extern int get_mce_event(struct machine_check_event *mce, bool release); extern void release_mce_event(void); extern void machine_check_queue_event(void); diff --git a/arch/powerpc/include/asm/opal.h b/arch/powerpc/include/asm/opal.h index ed82142a325111ca18ecbc5ad05ec5760cb03a87..ad67c40c1a217955c249403678e5f73eb6fe4722 100644 --- a/arch/powerpc/include/asm/opal.h +++ b/arch/powerpc/include/asm/opal.h @@ -833,6 +833,8 @@ int64_t opal_sync_host_reboot(void); /* Internal functions */ extern int early_init_dt_scan_opal(unsigned long node, const char *uname, int depth, void *data); +extern int early_init_dt_scan_recoverable_ranges(unsigned long node, + const char *uname, int depth, void *data); extern int opal_get_chars(uint32_t vtermno, char *buf, int count); extern int opal_put_chars(uint32_t vtermno, const char *buf, int total_len); @@ -863,6 +865,7 @@ extern void opal_nvram_init(void); extern void opal_flash_init(void); extern int opal_machine_check(struct pt_regs *regs); +extern bool opal_mce_check_early_recovery(struct pt_regs *regs); extern void opal_shutdown(void); diff --git a/arch/powerpc/kernel/mce.c b/arch/powerpc/kernel/mce.c index cadef7e64e4245e816f0878c63ebab43855c15c2..a7fd4cb78b788e01a6545964572a4af44b28bc28 100644 --- a/arch/powerpc/kernel/mce.c +++ b/arch/powerpc/kernel/mce.c @@ -70,7 +70,7 @@ static void mce_set_error_info(struct machine_check_event *mce, */ void save_mce_event(struct pt_regs *regs, long handled, struct mce_error_info *mce_err, - uint64_t addr) + uint64_t nip, uint64_t addr) { uint64_t srr1; int index = __get_cpu_var(mce_nest_count)++; @@ -86,7 +86,7 @@ void save_mce_event(struct pt_regs *regs, long handled, /* Populate generic machine check info */ mce->version = MCE_V1; - mce->srr0 = regs->nip; + mce->srr0 = nip; mce->srr1 = regs->msr; mce->gpr3 = regs->gpr[3]; mce->in_use = 1; diff --git a/arch/powerpc/kernel/mce_power.c b/arch/powerpc/kernel/mce_power.c index 27c93f41166f4216d5bd473e3e1aa397817c4cdb..aa9aff3d6ad3543fac861e06391fc067e7f91f55 100644 --- a/arch/powerpc/kernel/mce_power.c +++ b/arch/powerpc/kernel/mce_power.c @@ -26,6 +26,7 @@ #include #include #include +#include /* flush SLBs and reload */ static void flush_and_reload_slb(void) @@ -197,13 +198,32 @@ static void mce_get_derror_p7(struct mce_error_info *mce_err, uint64_t dsisr) } } +static long mce_handle_ue_error(struct pt_regs *regs) +{ + long handled = 0; + + /* + * On specific SCOM read via MMIO we may get a machine check + * exception with SRR0 pointing inside opal. If that is the + * case OPAL may have recovery address to re-read SCOM data in + * different way and hence we can recover from this MC. + */ + + if (ppc_md.mce_check_early_recovery) { + if (ppc_md.mce_check_early_recovery(regs)) + handled = 1; + } + return handled; +} + long __machine_check_early_realmode_p7(struct pt_regs *regs) { - uint64_t srr1, addr; + uint64_t srr1, nip, addr; long handled = 1; struct mce_error_info mce_error_info = { 0 }; srr1 = regs->msr; + nip = regs->nip; /* * Handle memory errors depending whether this was a load/store or @@ -221,7 +241,11 @@ long __machine_check_early_realmode_p7(struct pt_regs *regs) addr = regs->nip; } - save_mce_event(regs, handled, &mce_error_info, addr); + /* Handle UE error. */ + if (mce_error_info.error_type == MCE_ERROR_TYPE_UE) + handled = mce_handle_ue_error(regs); + + save_mce_event(regs, handled, &mce_error_info, nip, addr); return handled; } @@ -263,11 +287,12 @@ static long mce_handle_derror_p8(uint64_t dsisr) long __machine_check_early_realmode_p8(struct pt_regs *regs) { - uint64_t srr1, addr; + uint64_t srr1, nip, addr; long handled = 1; struct mce_error_info mce_error_info = { 0 }; srr1 = regs->msr; + nip = regs->nip; if (P7_SRR1_MC_LOADSTORE(srr1)) { handled = mce_handle_derror_p8(regs->dsisr); @@ -279,6 +304,10 @@ long __machine_check_early_realmode_p8(struct pt_regs *regs) addr = regs->nip; } - save_mce_event(regs, handled, &mce_error_info, addr); + /* Handle UE error. */ + if (mce_error_info.error_type == MCE_ERROR_TYPE_UE) + handled = mce_handle_ue_error(regs); + + save_mce_event(regs, handled, &mce_error_info, nip, addr); return handled; } diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c index f58c0d3aaeb497697aaa7ed75874ddee33146652..d711b7eb05aa30da72122c02ba3e6b80ef3c8ef8 100644 --- a/arch/powerpc/kernel/prom.c +++ b/arch/powerpc/kernel/prom.c @@ -752,6 +752,11 @@ void __init early_init_devtree(void *params) spinning_secondaries = boot_cpu_count - 1; #endif +#ifdef CONFIG_PPC_POWERNV + /* Scan and build the list of machine check recoverable ranges */ + of_scan_flat_dt(early_init_dt_scan_recoverable_ranges, NULL); +#endif + DBG(" <- early_init_devtree()\n"); } diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c index 65499adaecff2a1e2367612ece5e051028e38634..d5f11d689d6c1441eb8266dacff3d7cdfda4b793 100644 --- a/arch/powerpc/platforms/powernv/opal.c +++ b/arch/powerpc/platforms/powernv/opal.c @@ -21,6 +21,7 @@ #include #include #include +#include #include #include #include @@ -33,8 +34,18 @@ struct kobject *opal_kobj; struct opal { u64 base; u64 entry; + u64 size; } opal; +struct mcheck_recoverable_range { + u64 start_addr; + u64 end_addr; + u64 recover_addr; +}; + +static struct mcheck_recoverable_range *mc_recoverable_range; +static int mc_recoverable_range_len; + static struct device_node *opal_node; static DEFINE_SPINLOCK(opal_write_lock); extern u64 opal_mc_secondary_handler[]; @@ -49,25 +60,29 @@ static atomic_t opal_notifier_hold = ATOMIC_INIT(0); int __init early_init_dt_scan_opal(unsigned long node, const char *uname, int depth, void *data) { - const void *basep, *entryp; - unsigned long basesz, entrysz; + const void *basep, *entryp, *sizep; + unsigned long basesz, entrysz, runtimesz; if (depth != 1 || strcmp(uname, "ibm,opal") != 0) return 0; basep = of_get_flat_dt_prop(node, "opal-base-address", &basesz); entryp = of_get_flat_dt_prop(node, "opal-entry-address", &entrysz); + sizep = of_get_flat_dt_prop(node, "opal-runtime-size", &runtimesz); - if (!basep || !entryp) + if (!basep || !entryp || !sizep) return 1; opal.base = of_read_number(basep, basesz/4); opal.entry = of_read_number(entryp, entrysz/4); + opal.size = of_read_number(sizep, runtimesz/4); pr_debug("OPAL Base = 0x%llx (basep=%p basesz=%ld)\n", opal.base, basep, basesz); pr_debug("OPAL Entry = 0x%llx (entryp=%p basesz=%ld)\n", opal.entry, entryp, entrysz); + pr_debug("OPAL Entry = 0x%llx (sizep=%p runtimesz=%ld)\n", + opal.size, sizep, runtimesz); powerpc_firmware_features |= FW_FEATURE_OPAL; if (of_flat_dt_is_compatible(node, "ibm,opal-v3")) { @@ -84,6 +99,53 @@ int __init early_init_dt_scan_opal(unsigned long node, return 1; } +int __init early_init_dt_scan_recoverable_ranges(unsigned long node, + const char *uname, int depth, void *data) +{ + unsigned long i, size; + const __be32 *prop; + + if (depth != 1 || strcmp(uname, "ibm,opal") != 0) + return 0; + + prop = of_get_flat_dt_prop(node, "mcheck-recoverable-ranges", &size); + + if (!prop) + return 1; + + pr_debug("Found machine check recoverable ranges.\n"); + + /* + * Allocate a buffer to hold the MC recoverable ranges. We would be + * accessing them in real mode, hence it needs to be within + * RMO region. + */ + mc_recoverable_range =__va(memblock_alloc_base(size, __alignof__(u64), + ppc64_rma_size)); + memset(mc_recoverable_range, 0, size); + + /* + * Each recoverable address entry is an (start address,len, + * recover address) pair, * 2 cells each, totalling 4 cells per entry. + */ + for (i = 0; i < size / (sizeof(*prop) * 5); i++) { + mc_recoverable_range[i].start_addr = + of_read_number(prop + (i * 5) + 0, 2); + mc_recoverable_range[i].end_addr = + mc_recoverable_range[i].start_addr + + of_read_number(prop + (i * 5) + 2, 1); + mc_recoverable_range[i].recover_addr = + of_read_number(prop + (i * 5) + 3, 2); + + pr_debug("Machine check recoverable range: %llx..%llx: %llx\n", + mc_recoverable_range[i].start_addr, + mc_recoverable_range[i].end_addr, + mc_recoverable_range[i].recover_addr); + } + mc_recoverable_range_len = i; + return 1; +} + static int __init opal_register_exception_handlers(void) { #ifdef __BIG_ENDIAN__ @@ -401,6 +463,38 @@ int opal_machine_check(struct pt_regs *regs) return 0; } +static uint64_t find_recovery_address(uint64_t nip) +{ + int i; + + for (i = 0; i < mc_recoverable_range_len; i++) + if ((nip >= mc_recoverable_range[i].start_addr) && + (nip < mc_recoverable_range[i].end_addr)) + return mc_recoverable_range[i].recover_addr; + return 0; +} + +bool opal_mce_check_early_recovery(struct pt_regs *regs) +{ + uint64_t recover_addr = 0; + + if (!opal.base || !opal.size) + goto out; + + if ((regs->nip >= opal.base) && + (regs->nip <= (opal.base + opal.size))) + recover_addr = find_recovery_address(regs->nip); + + /* + * Setup regs->nip to rfi into fixup address. + */ + if (recover_addr) + regs->nip = recover_addr; + +out: + return !!recover_addr; +} + static irqreturn_t opal_interrupt(int irq, void *data) { __be64 events; diff --git a/arch/powerpc/platforms/powernv/setup.c b/arch/powerpc/platforms/powernv/setup.c index 110f4fbd319f628373522e99672a95dcffda6688..2d808456567634e4e2cc50099256161f06a5e7c9 100644 --- a/arch/powerpc/platforms/powernv/setup.c +++ b/arch/powerpc/platforms/powernv/setup.c @@ -188,6 +188,7 @@ static void __init pnv_setup_machdep_opal(void) ppc_md.power_off = pnv_power_off; ppc_md.halt = pnv_halt; ppc_md.machine_check_exception = opal_machine_check; + ppc_md.mce_check_early_recovery = opal_mce_check_early_recovery; } #ifdef CONFIG_PPC_POWERNV_RTAS