From: travis@sgi.com Date: Wed, 25 Jan 2017 16:35:19 +0000 (-0600) Subject: x86/platform/UV: Add Support for UV4 Hubless NMIs X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=abdf1df6bc0416ec19b841e92b497ca55b23454c;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git x86/platform/UV: Add Support for UV4 Hubless NMIs Merge new UV Hubless NMI support into existing UV NMI handler. Signed-off-by: Mike Travis Reviewed-by: Russ Anderson Acked-by: Thomas Gleixner Acked-by: Dimitri Sivanich Cc: Linus Torvalds Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/20170125163517.585269837@asylum.americas.sgi.com Signed-off-by: Ingo Molnar --- diff --git a/arch/x86/include/asm/uv/uv_hub.h b/arch/x86/include/asm/uv/uv_hub.h index 097b80c989c4..72e8300b1e8a 100644 --- a/arch/x86/include/asm/uv/uv_hub.h +++ b/arch/x86/include/asm/uv/uv_hub.h @@ -772,6 +772,7 @@ static inline int uv_num_possible_blades(void) /* Per Hub NMI support */ extern void uv_nmi_setup(void); +extern void uv_nmi_setup_hubless(void); /* BMC sets a bit this MMR non-zero before sending an NMI */ #define UVH_NMI_MMR UVH_SCRATCH5 @@ -799,6 +800,8 @@ struct uv_hub_nmi_s { atomic_t read_mmr_count; /* count of MMR reads */ atomic_t nmi_count; /* count of true UV NMIs */ unsigned long nmi_value; /* last value read from NMI MMR */ + bool hub_present; /* false means UV hubless system */ + bool pch_owner; /* indicates this hub owns PCH */ }; struct uv_cpu_nmi_s { diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c index d02cc7e65e4d..e9f8f8cdd570 100644 --- a/arch/x86/kernel/apic/x2apic_uv_x.c +++ b/arch/x86/kernel/apic/x2apic_uv_x.c @@ -1514,6 +1514,8 @@ void __init uv_system_init(void) if (is_uv_system()) uv_system_init_hub(); + else + uv_nmi_setup_hubless(); } apic_driver(apic_x2apic_uv_x); diff --git a/arch/x86/platform/uv/uv_nmi.c b/arch/x86/platform/uv/uv_nmi.c index 8410e7d0a5b5..df7b092941fe 100644 --- a/arch/x86/platform/uv/uv_nmi.c +++ b/arch/x86/platform/uv/uv_nmi.c @@ -67,6 +67,18 @@ static struct uv_hub_nmi_s **uv_hub_nmi_list; DEFINE_PER_CPU(struct uv_cpu_nmi_s, uv_cpu_nmi); EXPORT_PER_CPU_SYMBOL_GPL(uv_cpu_nmi); +/* UV hubless values */ +#define NMI_CONTROL_PORT 0x70 +#define NMI_DUMMY_PORT 0x71 +#define GPI_NMI_STS_GPP_D_0 0x164 +#define GPI_NMI_ENA_GPP_D_0 0x174 +#define STS_GPP_D_0_MASK 0x1 +#define PAD_CFG_DW0_GPP_D_0 0x4c0 +#define GPIROUTNMI (1ul << 17) +#define PCH_PCR_GPIO_1_BASE 0xfdae0000ul +#define PCH_PCR_GPIO_ADDRESS(offset) (int *)((u64)(pch_base) | (u64)(offset)) + +static u64 *pch_base; static unsigned long nmi_mmr; static unsigned long nmi_mmr_clear; static unsigned long nmi_mmr_pending; @@ -144,6 +156,19 @@ module_param_named(wait_count, uv_nmi_wait_count, int, 0644); static int uv_nmi_retry_count = 500; module_param_named(retry_count, uv_nmi_retry_count, int, 0644); +static bool uv_pch_intr_enable = true; +static bool uv_pch_intr_now_enabled; +module_param_named(pch_intr_enable, uv_pch_intr_enable, bool, 0644); + +static int uv_nmi_debug; +module_param_named(debug, uv_nmi_debug, int, 0644); + +#define nmi_debug(fmt, ...) \ + do { \ + if (uv_nmi_debug) \ + pr_info(fmt, ##__VA_ARGS__); \ + } while (0) + /* * Valid NMI Actions: * "dump" - dump process stack for each cpu @@ -191,6 +216,77 @@ static inline void uv_local_mmr_clear_nmi(void) uv_write_local_mmr(nmi_mmr_clear, nmi_mmr_pending); } +/* + * UV hubless NMI handler functions + */ +static inline void uv_reassert_nmi(void) +{ + /* (from arch/x86/include/asm/mach_traps.h) */ + outb(0x8f, NMI_CONTROL_PORT); + inb(NMI_DUMMY_PORT); /* dummy read */ + outb(0x0f, NMI_CONTROL_PORT); + inb(NMI_DUMMY_PORT); /* dummy read */ +} + +static void uv_init_hubless_pch_io(int offset, int mask, int data) +{ + int *addr = PCH_PCR_GPIO_ADDRESS(offset); + int readd = readl(addr); + + if (mask) { /* OR in new data */ + int writed = (readd & ~mask) | data; + + nmi_debug("UV:PCH: %p = %x & %x | %x (%x)\n", + addr, readd, ~mask, data, writed); + writel(writed, addr); + } else if (readd & data) { /* clear status bit */ + nmi_debug("UV:PCH: %p = %x\n", addr, data); + writel(data, addr); + } + + (void)readl(addr); /* flush write data */ +} + +static void uv_nmi_setup_hubless_intr(void) +{ + uv_pch_intr_now_enabled = uv_pch_intr_enable; + + uv_init_hubless_pch_io( + PAD_CFG_DW0_GPP_D_0, GPIROUTNMI, + uv_pch_intr_now_enabled ? GPIROUTNMI : 0); + + nmi_debug("UV:NMI: GPP_D_0 interrupt %s\n", + uv_pch_intr_now_enabled ? "enabled" : "disabled"); +} + +static int uv_nmi_test_hubless(struct uv_hub_nmi_s *hub_nmi) +{ + int *pstat = PCH_PCR_GPIO_ADDRESS(GPI_NMI_STS_GPP_D_0); + int status = *pstat; + + hub_nmi->nmi_value = status; + atomic_inc(&hub_nmi->read_mmr_count); + + if (!(status & STS_GPP_D_0_MASK)) /* Not a UV external NMI */ + return 0; + + *pstat = STS_GPP_D_0_MASK; /* Is a UV NMI: clear GPP_D_0 status */ + (void)*pstat; /* flush write */ + + return 1; +} + +static int uv_test_nmi(struct uv_hub_nmi_s *hub_nmi) +{ + if (hub_nmi->hub_present) + return uv_nmi_test_mmr(hub_nmi); + + if (hub_nmi->pch_owner) /* Only PCH owner can check status */ + return uv_nmi_test_hubless(hub_nmi); + + return -1; +} + /* * If first cpu in on this hub, set hub_nmi "in_nmi" and "owner" values and * return true. If first cpu in on the system, set global "in_nmi" flag. @@ -214,6 +310,7 @@ static int uv_check_nmi(struct uv_hub_nmi_s *hub_nmi) { int cpu = smp_processor_id(); int nmi = 0; + int nmi_detected = 0; local64_inc(&uv_nmi_count); this_cpu_inc(uv_cpu_nmi.queries); @@ -224,20 +321,26 @@ static int uv_check_nmi(struct uv_hub_nmi_s *hub_nmi) break; if (raw_spin_trylock(&hub_nmi->nmi_lock)) { + nmi_detected = uv_test_nmi(hub_nmi); - /* check hub MMR NMI flag */ - if (uv_nmi_test_mmr(hub_nmi)) { + /* check flag for UV external NMI */ + if (nmi_detected > 0) { uv_set_in_nmi(cpu, hub_nmi); nmi = 1; break; } - /* MMR NMI flag is clear */ + /* A non-PCH node in a hubless system waits for NMI */ + else if (nmi_detected < 0) + goto slave_wait; + + /* MMR/PCH NMI flag is clear */ raw_spin_unlock(&hub_nmi->nmi_lock); } else { - /* wait a moment for the hub nmi locker to set flag */ - cpu_relax(); + + /* Wait a moment for the HUB NMI locker to set flag */ +slave_wait: cpu_relax(); udelay(uv_nmi_slave_delay); /* re-check hub in_nmi flag */ @@ -246,13 +349,20 @@ static int uv_check_nmi(struct uv_hub_nmi_s *hub_nmi) break; } - /* check if this BMC missed setting the MMR NMI flag */ + /* + * Check if this BMC missed setting the MMR NMI flag (or) + * UV hubless system where only PCH owner can check flag + */ if (!nmi) { nmi = atomic_read(&uv_in_nmi); if (nmi) uv_set_in_nmi(cpu, hub_nmi); } + /* If we're holding the hub lock, release it now */ + if (nmi_detected < 0) + raw_spin_unlock(&hub_nmi->nmi_lock); + } while (0); if (!nmi) @@ -269,7 +379,10 @@ static inline void uv_clear_nmi(int cpu) if (cpu == atomic_read(&hub_nmi->cpu_owner)) { atomic_set(&hub_nmi->cpu_owner, -1); atomic_set(&hub_nmi->in_nmi, 0); - uv_local_mmr_clear_nmi(); + if (hub_nmi->hub_present) + uv_local_mmr_clear_nmi(); + else + uv_reassert_nmi(); raw_spin_unlock(&hub_nmi->nmi_lock); } } @@ -297,11 +410,12 @@ static void uv_nmi_cleanup_mask(void) } } -/* Loop waiting as cpus enter nmi handler */ +/* Loop waiting as cpus enter NMI handler */ static int uv_nmi_wait_cpus(int first) { int i, j, k, n = num_online_cpus(); int last_k = 0, waiting = 0; + int cpu = smp_processor_id(); if (first) { cpumask_copy(uv_nmi_cpu_mask, cpu_online_mask); @@ -310,6 +424,12 @@ static int uv_nmi_wait_cpus(int first) k = n - cpumask_weight(uv_nmi_cpu_mask); } + /* PCH NMI causes only one cpu to respond */ + if (first && uv_pch_intr_now_enabled) { + cpumask_clear_cpu(cpu, uv_nmi_cpu_mask); + return n - k - 1; + } + udelay(uv_nmi_initial_delay); for (i = 0; i < uv_nmi_retry_count; i++) { int loop_delay = uv_nmi_loop_delay; @@ -358,7 +478,7 @@ static void uv_nmi_wait(int master) break; /* if not all made it in, send IPI NMI to them */ - pr_alert("UV: Sending NMI IPI to %d non-responding CPUs: %*pbl\n", + pr_alert("UV: Sending NMI IPI to %d CPUs: %*pbl\n", cpumask_weight(uv_nmi_cpu_mask), cpumask_pr_args(uv_nmi_cpu_mask)); @@ -538,7 +658,7 @@ static inline int uv_nmi_kdb_reason(void) #else /* !CONFIG_KGDB_KDB */ static inline int uv_nmi_kdb_reason(void) { - /* Insure user is expecting to attach gdb remote */ + /* Ensure user is expecting to attach gdb remote */ if (uv_nmi_action_is("kgdb")) return 0; @@ -626,15 +746,18 @@ int uv_handle_nmi(unsigned int reason, struct pt_regs *regs) /* Pause as all cpus enter the NMI handler */ uv_nmi_wait(master); - /* Dump state of each cpu */ - if (uv_nmi_action_is("ips") || uv_nmi_action_is("dump")) + /* Process actions other than "kdump": */ + if (uv_nmi_action_is("ips") || uv_nmi_action_is("dump")) { uv_nmi_dump_state(cpu, regs, master); - - /* Call KGDB/KDB if enabled */ - else if (uv_nmi_action_is("kdb") || uv_nmi_action_is("kgdb")) + } else if (uv_nmi_action_is("kdb") || uv_nmi_action_is("kgdb")) { uv_call_kgdb_kdb(cpu, regs, master); + } else { + if (master) + pr_alert("UV: unknown NMI action: %s\n", uv_nmi_action); + uv_nmi_sync_exit(master); + } - /* Clear per_cpu "in nmi" flag */ + /* Clear per_cpu "in_nmi" flag */ this_cpu_write(uv_cpu_nmi.state, UV_NMI_STATE_OUT); /* Clear MMR NMI flag on each hub */ @@ -648,6 +771,7 @@ int uv_handle_nmi(unsigned int reason, struct pt_regs *regs) atomic_set(&uv_nmi_cpu, -1); atomic_set(&uv_in_nmi, 0); atomic_set(&uv_nmi_kexec_failed, 0); + atomic_set(&uv_nmi_slave_continue, SLAVE_CLEAR); } uv_nmi_touch_watchdogs(); @@ -697,28 +821,53 @@ void uv_nmi_init(void) apic_write(APIC_LVT1, value); } -void uv_nmi_setup(void) +/* Setup HUB NMI info */ +void __init uv_nmi_setup_common(bool hubbed) { int size = sizeof(void *) * (1 << NODES_SHIFT); - int cpu, nid; + int cpu; - /* Setup hub nmi info */ - uv_nmi_setup_mmrs(); uv_hub_nmi_list = kzalloc(size, GFP_KERNEL); - pr_info("UV: NMI hub list @ 0x%p (%d)\n", uv_hub_nmi_list, size); + nmi_debug("UV: NMI hub list @ 0x%p (%d)\n", uv_hub_nmi_list, size); BUG_ON(!uv_hub_nmi_list); size = sizeof(struct uv_hub_nmi_s); for_each_present_cpu(cpu) { - nid = cpu_to_node(cpu); + int nid = cpu_to_node(cpu); if (uv_hub_nmi_list[nid] == NULL) { uv_hub_nmi_list[nid] = kzalloc_node(size, GFP_KERNEL, nid); BUG_ON(!uv_hub_nmi_list[nid]); raw_spin_lock_init(&(uv_hub_nmi_list[nid]->nmi_lock)); atomic_set(&uv_hub_nmi_list[nid]->cpu_owner, -1); + uv_hub_nmi_list[nid]->hub_present = hubbed; + uv_hub_nmi_list[nid]->pch_owner = (nid == 0); } uv_hub_nmi_per(cpu) = uv_hub_nmi_list[nid]; } BUG_ON(!alloc_cpumask_var(&uv_nmi_cpu_mask, GFP_KERNEL)); +} + +/* Setup for UV Hub systems */ +void __init uv_nmi_setup(void) +{ + uv_nmi_setup_mmrs(); + uv_nmi_setup_common(true); + uv_register_nmi_notifier(); + pr_info("UV: Hub NMI enabled\n"); +} + +/* Setup for UV Hubless systems */ +void __init uv_nmi_setup_hubless(void) +{ + uv_nmi_setup_common(false); + pch_base = xlate_dev_mem_ptr(PCH_PCR_GPIO_1_BASE); + nmi_debug("UV: PCH base:%p from 0x%lx, GPP_D_0\n", + pch_base, PCH_PCR_GPIO_1_BASE); + uv_init_hubless_pch_io(GPI_NMI_ENA_GPP_D_0, + STS_GPP_D_0_MASK, STS_GPP_D_0_MASK); + uv_nmi_setup_hubless_intr(); + /* Ensure NMI enabled in Processor Interface Reg: */ + uv_reassert_nmi(); uv_register_nmi_notifier(); + pr_info("UV: Hubless NMI enabled\n"); }