diff options
Diffstat (limited to 'arch/x86/kernel/apic/apic.c')
| -rw-r--r-- | arch/x86/kernel/apic/apic.c | 3010 |
1 files changed, 3010 insertions, 0 deletions
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c new file mode 100644 index 000000000..770557110 --- /dev/null +++ b/arch/x86/kernel/apic/apic.c @@ -0,0 +1,3010 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Local APIC handling, local APIC timers + * + * (c) 1999, 2000, 2009 Ingo Molnar <mingo@redhat.com> + * + * Fixes + * Maciej W. Rozycki : Bits for genuine 82489DX APICs; + * thanks to Eric Gilmore + * and Rolf G. Tews + * for testing these extensively. + * Maciej W. Rozycki : Various updates and fixes. + * Mikael Pettersson : Power Management for UP-APIC. + * Pavel Machek and + * Mikael Pettersson : PM converted to driver model. + */ + +#include <linux/perf_event.h> +#include <linux/kernel_stat.h> +#include <linux/mc146818rtc.h> +#include <linux/acpi_pmtmr.h> +#include <linux/clockchips.h> +#include <linux/interrupt.h> +#include <linux/memblock.h> +#include <linux/ftrace.h> +#include <linux/ioport.h> +#include <linux/export.h> +#include <linux/syscore_ops.h> +#include <linux/delay.h> +#include <linux/timex.h> +#include <linux/i8253.h> +#include <linux/dmar.h> +#include <linux/init.h> +#include <linux/cpu.h> +#include <linux/dmi.h> +#include <linux/smp.h> +#include <linux/mm.h> + +#include <asm/trace/irq_vectors.h> +#include <asm/irq_remapping.h> +#include <asm/pc-conf-reg.h> +#include <asm/perf_event.h> +#include <asm/x86_init.h> +#include <linux/atomic.h> +#include <asm/barrier.h> +#include <asm/mpspec.h> +#include <asm/i8259.h> +#include <asm/proto.h> +#include <asm/traps.h> +#include <asm/apic.h> +#include <asm/acpi.h> +#include <asm/io_apic.h> +#include <asm/desc.h> +#include <asm/hpet.h> +#include <asm/mtrr.h> +#include <asm/time.h> +#include <asm/smp.h> +#include <asm/mce.h> +#include <asm/tsc.h> +#include <asm/hypervisor.h> +#include <asm/cpu_device_id.h> +#include <asm/intel-family.h> +#include <asm/irq_regs.h> +#include <asm/cpu.h> + +unsigned int num_processors; + +unsigned disabled_cpus; + +/* Processor that is doing the boot up */ +unsigned int boot_cpu_physical_apicid __ro_after_init = -1U; +EXPORT_SYMBOL_GPL(boot_cpu_physical_apicid); + +u8 boot_cpu_apic_version __ro_after_init; + +/* + * The highest APIC ID seen during enumeration. + */ +static unsigned int max_physical_apicid; + +/* + * Bitmask of physically existing CPUs: + */ +physid_mask_t phys_cpu_present_map; + +/* + * Processor to be disabled specified by kernel parameter + * disable_cpu_apicid=<int>, mostly used for the kdump 2nd kernel to + * avoid undefined behaviour caused by sending INIT from AP to BSP. + */ +static unsigned int disabled_cpu_apicid __ro_after_init = BAD_APICID; + +/* + * This variable controls which CPUs receive external NMIs. By default, + * external NMIs are delivered only to the BSP. + */ +static int apic_extnmi __ro_after_init = APIC_EXTNMI_BSP; + +/* + * Hypervisor supports 15 bits of APIC ID in MSI Extended Destination ID + */ +static bool virt_ext_dest_id __ro_after_init; + +/* + * Map cpu index to physical APIC ID + */ +DEFINE_EARLY_PER_CPU_READ_MOSTLY(u16, x86_cpu_to_apicid, BAD_APICID); +DEFINE_EARLY_PER_CPU_READ_MOSTLY(u16, x86_bios_cpu_apicid, BAD_APICID); +DEFINE_EARLY_PER_CPU_READ_MOSTLY(u32, x86_cpu_to_acpiid, U32_MAX); +EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_apicid); +EXPORT_EARLY_PER_CPU_SYMBOL(x86_bios_cpu_apicid); +EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_acpiid); + +#ifdef CONFIG_X86_32 + +/* + * On x86_32, the mapping between cpu and logical apicid may vary + * depending on apic in use. The following early percpu variable is + * used for the mapping. This is where the behaviors of x86_64 and 32 + * actually diverge. Let's keep it ugly for now. + */ +DEFINE_EARLY_PER_CPU_READ_MOSTLY(int, x86_cpu_to_logical_apicid, BAD_APICID); + +/* Local APIC was disabled by the BIOS and enabled by the kernel */ +static int enabled_via_apicbase __ro_after_init; + +/* + * Handle interrupt mode configuration register (IMCR). + * This register controls whether the interrupt signals + * that reach the BSP come from the master PIC or from the + * local APIC. Before entering Symmetric I/O Mode, either + * the BIOS or the operating system must switch out of + * PIC Mode by changing the IMCR. + */ +static inline void imcr_pic_to_apic(void) +{ + /* NMI and 8259 INTR go through APIC */ + pc_conf_set(PC_CONF_MPS_IMCR, 0x01); +} + +static inline void imcr_apic_to_pic(void) +{ + /* NMI and 8259 INTR go directly to BSP */ + pc_conf_set(PC_CONF_MPS_IMCR, 0x00); +} +#endif + +/* + * Knob to control our willingness to enable the local APIC. + * + * +1=force-enable + */ +static int force_enable_local_apic __initdata; + +/* + * APIC command line parameters + */ +static int __init parse_lapic(char *arg) +{ + if (IS_ENABLED(CONFIG_X86_32) && !arg) + force_enable_local_apic = 1; + else if (arg && !strncmp(arg, "notscdeadline", 13)) + setup_clear_cpu_cap(X86_FEATURE_TSC_DEADLINE_TIMER); + return 0; +} +early_param("lapic", parse_lapic); + +#ifdef CONFIG_X86_64 +static int apic_calibrate_pmtmr __initdata; +static __init int setup_apicpmtimer(char *s) +{ + apic_calibrate_pmtmr = 1; + notsc_setup(NULL); + return 1; +} +__setup("apicpmtimer", setup_apicpmtimer); +#endif + +unsigned long mp_lapic_addr __ro_after_init; +int disable_apic __ro_after_init; +/* Disable local APIC timer from the kernel commandline or via dmi quirk */ +static int disable_apic_timer __initdata; +/* Local APIC timer works in C2 */ +int local_apic_timer_c2_ok __ro_after_init; +EXPORT_SYMBOL_GPL(local_apic_timer_c2_ok); + +/* + * Debug level, exported for io_apic.c + */ +int apic_verbosity __ro_after_init; + +int pic_mode __ro_after_init; + +/* Have we found an MP table */ +int smp_found_config __ro_after_init; + +static struct resource lapic_resource = { + .name = "Local APIC", + .flags = IORESOURCE_MEM | IORESOURCE_BUSY, +}; + +unsigned int lapic_timer_period = 0; + +static void apic_pm_activate(void); + +static unsigned long apic_phys __ro_after_init; + +/* + * Get the LAPIC version + */ +static inline int lapic_get_version(void) +{ + return GET_APIC_VERSION(apic_read(APIC_LVR)); +} + +/* + * Check, if the APIC is integrated or a separate chip + */ +static inline int lapic_is_integrated(void) +{ + return APIC_INTEGRATED(lapic_get_version()); +} + +/* + * Check, whether this is a modern or a first generation APIC + */ +static int modern_apic(void) +{ + /* AMD systems use old APIC versions, so check the CPU */ + if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD && + boot_cpu_data.x86 >= 0xf) + return 1; + + /* Hygon systems use modern APIC */ + if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) + return 1; + + return lapic_get_version() >= 0x14; +} + +/* + * right after this call apic become NOOP driven + * so apic->write/read doesn't do anything + */ +static void __init apic_disable(void) +{ + pr_info("APIC: switched to apic NOOP\n"); + apic = &apic_noop; +} + +void native_apic_wait_icr_idle(void) +{ + while (apic_read(APIC_ICR) & APIC_ICR_BUSY) + cpu_relax(); +} + +u32 native_safe_apic_wait_icr_idle(void) +{ + u32 send_status; + int timeout; + + timeout = 0; + do { + send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY; + if (!send_status) + break; + inc_irq_stat(icr_read_retry_count); + udelay(100); + } while (timeout++ < 1000); + + return send_status; +} + +void native_apic_icr_write(u32 low, u32 id) +{ + unsigned long flags; + + local_irq_save(flags); + apic_write(APIC_ICR2, SET_XAPIC_DEST_FIELD(id)); + apic_write(APIC_ICR, low); + local_irq_restore(flags); +} + +u64 native_apic_icr_read(void) +{ + u32 icr1, icr2; + + icr2 = apic_read(APIC_ICR2); + icr1 = apic_read(APIC_ICR); + + return icr1 | ((u64)icr2 << 32); +} + +#ifdef CONFIG_X86_32 +/** + * get_physical_broadcast - Get number of physical broadcast IDs + */ +int get_physical_broadcast(void) +{ + return modern_apic() ? 0xff : 0xf; +} +#endif + +/** + * lapic_get_maxlvt - get the maximum number of local vector table entries + */ +int lapic_get_maxlvt(void) +{ + /* + * - we always have APIC integrated on 64bit mode + * - 82489DXs do not report # of LVT entries + */ + return lapic_is_integrated() ? GET_APIC_MAXLVT(apic_read(APIC_LVR)) : 2; +} + +/* + * Local APIC timer + */ + +/* Clock divisor */ +#define APIC_DIVISOR 16 +#define TSC_DIVISOR 8 + +/* i82489DX specific */ +#define I82489DX_BASE_DIVIDER (((0x2) << 18)) + +/* + * This function sets up the local APIC timer, with a timeout of + * 'clocks' APIC bus clock. During calibration we actually call + * this function twice on the boot CPU, once with a bogus timeout + * value, second time for real. The other (noncalibrating) CPUs + * call this function only once, with the real, calibrated value. + * + * We do reads before writes even if unnecessary, to get around the + * P5 APIC double write bug. + */ +static void __setup_APIC_LVTT(unsigned int clocks, int oneshot, int irqen) +{ + unsigned int lvtt_value, tmp_value; + + lvtt_value = LOCAL_TIMER_VECTOR; + if (!oneshot) + lvtt_value |= APIC_LVT_TIMER_PERIODIC; + else if (boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER)) + lvtt_value |= APIC_LVT_TIMER_TSCDEADLINE; + + /* + * The i82489DX APIC uses bit 18 and 19 for the base divider. This + * overlaps with bit 18 on integrated APICs, but is not documented + * in the SDM. No problem though. i82489DX equipped systems do not + * have TSC deadline timer. + */ + if (!lapic_is_integrated()) + lvtt_value |= I82489DX_BASE_DIVIDER; + + if (!irqen) + lvtt_value |= APIC_LVT_MASKED; + + apic_write(APIC_LVTT, lvtt_value); + + if (lvtt_value & APIC_LVT_TIMER_TSCDEADLINE) { + /* + * See Intel SDM: TSC-Deadline Mode chapter. In xAPIC mode, + * writing to the APIC LVTT and TSC_DEADLINE MSR isn't serialized. + * According to Intel, MFENCE can do the serialization here. + */ + asm volatile("mfence" : : : "memory"); + return; + } + + /* + * Divide PICLK by 16 + */ + tmp_value = apic_read(APIC_TDCR); + apic_write(APIC_TDCR, + (tmp_value & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE)) | + APIC_TDR_DIV_16); + + if (!oneshot) + apic_write(APIC_TMICT, clocks / APIC_DIVISOR); +} + +/* + * Setup extended LVT, AMD specific + * + * Software should use the LVT offsets the BIOS provides. The offsets + * are determined by the subsystems using it like those for MCE + * threshold or IBS. On K8 only offset 0 (APIC500) and MCE interrupts + * are supported. Beginning with family 10h at least 4 offsets are + * available. + * + * Since the offsets must be consistent for all cores, we keep track + * of the LVT offsets in software and reserve the offset for the same + * vector also to be used on other cores. An offset is freed by + * setting the entry to APIC_EILVT_MASKED. + * + * If the BIOS is right, there should be no conflicts. Otherwise a + * "[Firmware Bug]: ..." error message is generated. However, if + * software does not properly determines the offsets, it is not + * necessarily a BIOS bug. + */ + +static atomic_t eilvt_offsets[APIC_EILVT_NR_MAX]; + +static inline int eilvt_entry_is_changeable(unsigned int old, unsigned int new) +{ + return (old & APIC_EILVT_MASKED) + || (new == APIC_EILVT_MASKED) + || ((new & ~APIC_EILVT_MASKED) == old); +} + +static unsigned int reserve_eilvt_offset(int offset, unsigned int new) +{ + unsigned int rsvd, vector; + + if (offset >= APIC_EILVT_NR_MAX) + return ~0; + + rsvd = atomic_read(&eilvt_offsets[offset]); + do { + vector = rsvd & ~APIC_EILVT_MASKED; /* 0: unassigned */ + if (vector && !eilvt_entry_is_changeable(vector, new)) + /* may not change if vectors are different */ + return rsvd; + } while (!atomic_try_cmpxchg(&eilvt_offsets[offset], &rsvd, new)); + + rsvd = new & ~APIC_EILVT_MASKED; + if (rsvd && rsvd != vector) + pr_info("LVT offset %d assigned for vector 0x%02x\n", + offset, rsvd); + + return new; +} + +/* + * If mask=1, the LVT entry does not generate interrupts while mask=0 + * enables the vector. See also the BKDGs. Must be called with + * preemption disabled. + */ + +int setup_APIC_eilvt(u8 offset, u8 vector, u8 msg_type, u8 mask) +{ + unsigned long reg = APIC_EILVTn(offset); + unsigned int new, old, reserved; + + new = (mask << 16) | (msg_type << 8) | vector; + old = apic_read(reg); + reserved = reserve_eilvt_offset(offset, new); + + if (reserved != new) { + pr_err(FW_BUG "cpu %d, try to use APIC%lX (LVT offset %d) for " + "vector 0x%x, but the register is already in use for " + "vector 0x%x on another cpu\n", + smp_processor_id(), reg, offset, new, reserved); + return -EINVAL; + } + + if (!eilvt_entry_is_changeable(old, new)) { + pr_err(FW_BUG "cpu %d, try to use APIC%lX (LVT offset %d) for " + "vector 0x%x, but the register is already in use for " + "vector 0x%x on this cpu\n", + smp_processor_id(), reg, offset, new, old); + return -EBUSY; + } + + apic_write(reg, new); + + return 0; +} +EXPORT_SYMBOL_GPL(setup_APIC_eilvt); + +/* + * Program the next event, relative to now + */ +static int lapic_next_event(unsigned long delta, + struct clock_event_device *evt) +{ + apic_write(APIC_TMICT, delta); + return 0; +} + +static int lapic_next_deadline(unsigned long delta, + struct clock_event_device *evt) +{ + u64 tsc; + + /* This MSR is special and need a special fence: */ + weak_wrmsr_fence(); + + tsc = rdtsc(); + wrmsrl(MSR_IA32_TSC_DEADLINE, tsc + (((u64) delta) * TSC_DIVISOR)); + return 0; +} + +static int lapic_timer_shutdown(struct clock_event_device *evt) +{ + unsigned int v; + + /* Lapic used as dummy for broadcast ? */ + if (evt->features & CLOCK_EVT_FEAT_DUMMY) + return 0; + + v = apic_read(APIC_LVTT); + v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR); + apic_write(APIC_LVTT, v); + apic_write(APIC_TMICT, 0); + return 0; +} + +static inline int +lapic_timer_set_periodic_oneshot(struct clock_event_device *evt, bool oneshot) +{ + /* Lapic used as dummy for broadcast ? */ + if (evt->features & CLOCK_EVT_FEAT_DUMMY) + return 0; + + __setup_APIC_LVTT(lapic_timer_period, oneshot, 1); + return 0; +} + +static int lapic_timer_set_periodic(struct clock_event_device *evt) +{ + return lapic_timer_set_periodic_oneshot(evt, false); +} + +static int lapic_timer_set_oneshot(struct clock_event_device *evt) +{ + return lapic_timer_set_periodic_oneshot(evt, true); +} + +/* + * Local APIC timer broadcast function + */ +static void lapic_timer_broadcast(const struct cpumask *mask) +{ +#ifdef CONFIG_SMP + apic->send_IPI_mask(mask, LOCAL_TIMER_VECTOR); +#endif +} + + +/* + * The local apic timer can be used for any function which is CPU local. + */ +static struct clock_event_device lapic_clockevent = { + .name = "lapic", + .features = CLOCK_EVT_FEAT_PERIODIC | + CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_C3STOP + | CLOCK_EVT_FEAT_DUMMY, + .shift = 32, + .set_state_shutdown = lapic_timer_shutdown, + .set_state_periodic = lapic_timer_set_periodic, + .set_state_oneshot = lapic_timer_set_oneshot, + .set_state_oneshot_stopped = lapic_timer_shutdown, + .set_next_event = lapic_next_event, + .broadcast = lapic_timer_broadcast, + .rating = 100, + .irq = -1, +}; +static DEFINE_PER_CPU(struct clock_event_device, lapic_events); + +static const struct x86_cpu_id deadline_match[] __initconst = { + X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(HASWELL_X, X86_STEPPINGS(0x2, 0x2), 0x3a), /* EP */ + X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(HASWELL_X, X86_STEPPINGS(0x4, 0x4), 0x0f), /* EX */ + + X86_MATCH_INTEL_FAM6_MODEL( BROADWELL_X, 0x0b000020), + + X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(BROADWELL_D, X86_STEPPINGS(0x2, 0x2), 0x00000011), + X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(BROADWELL_D, X86_STEPPINGS(0x3, 0x3), 0x0700000e), + X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(BROADWELL_D, X86_STEPPINGS(0x4, 0x4), 0x0f00000c), + X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(BROADWELL_D, X86_STEPPINGS(0x5, 0x5), 0x0e000003), + + X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(SKYLAKE_X, X86_STEPPINGS(0x3, 0x3), 0x01000136), + X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(SKYLAKE_X, X86_STEPPINGS(0x4, 0x4), 0x02000014), + X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(SKYLAKE_X, X86_STEPPINGS(0x5, 0xf), 0), + + X86_MATCH_INTEL_FAM6_MODEL( HASWELL, 0x22), + X86_MATCH_INTEL_FAM6_MODEL( HASWELL_L, 0x20), + X86_MATCH_INTEL_FAM6_MODEL( HASWELL_G, 0x17), + + X86_MATCH_INTEL_FAM6_MODEL( BROADWELL, 0x25), + X86_MATCH_INTEL_FAM6_MODEL( BROADWELL_G, 0x17), + + X86_MATCH_INTEL_FAM6_MODEL( SKYLAKE_L, 0xb2), + X86_MATCH_INTEL_FAM6_MODEL( SKYLAKE, 0xb2), + + X86_MATCH_INTEL_FAM6_MODEL( KABYLAKE_L, 0x52), + X86_MATCH_INTEL_FAM6_MODEL( KABYLAKE, 0x52), + + {}, +}; + +static __init bool apic_validate_deadline_timer(void) +{ + const struct x86_cpu_id *m; + u32 rev; + + if (!boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER)) + return false; + if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) + return true; + + m = x86_match_cpu(deadline_match); + if (!m) + return true; + + rev = (u32)m->driver_data; + + if (boot_cpu_data.microcode >= rev) + return true; + + setup_clear_cpu_cap(X86_FEATURE_TSC_DEADLINE_TIMER); + pr_err(FW_BUG "TSC_DEADLINE disabled due to Errata; " + "please update microcode to version: 0x%x (or later)\n", rev); + return false; +} + +/* + * Setup the local APIC timer for this CPU. Copy the initialized values + * of the boot CPU and register the clock event in the framework. + */ +static void setup_APIC_timer(void) +{ + struct clock_event_device *levt = this_cpu_ptr(&lapic_events); + + if (this_cpu_has(X86_FEATURE_ARAT)) { + lapic_clockevent.features &= ~CLOCK_EVT_FEAT_C3STOP; + /* Make LAPIC timer preferable over percpu HPET */ + lapic_clockevent.rating = 150; + } + + memcpy(levt, &lapic_clockevent, sizeof(*levt)); + levt->cpumask = cpumask_of(smp_processor_id()); + + if (this_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER)) { + levt->name = "lapic-deadline"; + levt->features &= ~(CLOCK_EVT_FEAT_PERIODIC | + CLOCK_EVT_FEAT_DUMMY); + levt->set_next_event = lapic_next_deadline; + clockevents_config_and_register(levt, + tsc_khz * (1000 / TSC_DIVISOR), + 0xF, ~0UL); + } else + clockevents_register_device(levt); +} + +/* + * Install the updated TSC frequency from recalibration at the TSC + * deadline clockevent devices. + */ +static void __lapic_update_tsc_freq(void *info) +{ + struct clock_event_device *levt = this_cpu_ptr(&lapic_events); + + if (!this_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER)) + return; + + clockevents_update_freq(levt, tsc_khz * (1000 / TSC_DIVISOR)); +} + +void lapic_update_tsc_freq(void) +{ + /* + * The clockevent device's ->mult and ->shift can both be + * changed. In order to avoid races, schedule the frequency + * update code on each CPU. + */ + on_each_cpu(__lapic_update_tsc_freq, NULL, 0); +} + +/* + * In this functions we calibrate APIC bus clocks to the external timer. + * + * We want to do the calibration only once since we want to have local timer + * irqs synchronous. CPUs connected by the same APIC bus have the very same bus + * frequency. + * + * This was previously done by reading the PIT/HPET and waiting for a wrap + * around to find out, that a tick has elapsed. I have a box, where the PIT + * readout is broken, so it never gets out of the wait loop again. This was + * also reported by others. + * + * Monitoring the jiffies value is inaccurate and the clockevents + * infrastructure allows us to do a simple substitution of the interrupt + * handler. + * + * The calibration routine also uses the pm_timer when possible, as the PIT + * happens to run way too slow (factor 2.3 on my VAIO CoreDuo, which goes + * back to normal later in the boot process). + */ + +#define LAPIC_CAL_LOOPS (HZ/10) + +static __initdata int lapic_cal_loops = -1; +static __initdata long lapic_cal_t1, lapic_cal_t2; +static __initdata unsigned long long lapic_cal_tsc1, lapic_cal_tsc2; +static __initdata unsigned long lapic_cal_pm1, lapic_cal_pm2; +static __initdata unsigned long lapic_cal_j1, lapic_cal_j2; + +/* + * Temporary interrupt handler and polled calibration function. + */ +static void __init lapic_cal_handler(struct clock_event_device *dev) +{ + unsigned long long tsc = 0; + long tapic = apic_read(APIC_TMCCT); + unsigned long pm = acpi_pm_read_early(); + + if (boot_cpu_has(X86_FEATURE_TSC)) + tsc = rdtsc(); + + switch (lapic_cal_loops++) { + case 0: + lapic_cal_t1 = tapic; + lapic_cal_tsc1 = tsc; + lapic_cal_pm1 = pm; + lapic_cal_j1 = jiffies; + break; + + case LAPIC_CAL_LOOPS: + lapic_cal_t2 = tapic; + lapic_cal_tsc2 = tsc; + if (pm < lapic_cal_pm1) + pm += ACPI_PM_OVRRUN; + lapic_cal_pm2 = pm; + lapic_cal_j2 = jiffies; + break; + } +} + +static int __init +calibrate_by_pmtimer(long deltapm, long *delta, long *deltatsc) +{ + const long pm_100ms = PMTMR_TICKS_PER_SEC / 10; + const long pm_thresh = pm_100ms / 100; + unsigned long mult; + u64 res; + +#ifndef CONFIG_X86_PM_TIMER + return -1; +#endif + + apic_printk(APIC_VERBOSE, "... PM-Timer delta = %ld\n", deltapm); + + /* Check, if the PM timer is available */ + if (!deltapm) + return -1; + + mult = clocksource_hz2mult(PMTMR_TICKS_PER_SEC, 22); + + if (deltapm > (pm_100ms - pm_thresh) && + deltapm < (pm_100ms + pm_thresh)) { + apic_printk(APIC_VERBOSE, "... PM-Timer result ok\n"); + return 0; + } + + res = (((u64)deltapm) * mult) >> 22; + do_div(res, 1000000); + pr_warn("APIC calibration not consistent " + "with PM-Timer: %ldms instead of 100ms\n", (long)res); + + /* Correct the lapic counter value */ + res = (((u64)(*delta)) * pm_100ms); + do_div(res, deltapm); + pr_info("APIC delta adjusted to PM-Timer: " + "%lu (%ld)\n", (unsigned long)res, *delta); + *delta = (long)res; + + /* Correct the tsc counter value */ + if (boot_cpu_has(X86_FEATURE_TSC)) { + res = (((u64)(*deltatsc)) * pm_100ms); + do_div(res, deltapm); + apic_printk(APIC_VERBOSE, "TSC delta adjusted to " + "PM-Timer: %lu (%ld)\n", + (unsigned long)res, *deltatsc); + *deltatsc = (long)res; + } + + return 0; +} + +static int __init lapic_init_clockevent(void) +{ + if (!lapic_timer_period) + return -1; + + /* Calculate the scaled math multiplication factor */ + lapic_clockevent.mult = div_sc(lapic_timer_period/APIC_DIVISOR, + TICK_NSEC, lapic_clockevent.shift); + lapic_clockevent.max_delta_ns = + clockevent_delta2ns(0x7FFFFFFF, &lapic_clockevent); + lapic_clockevent.max_delta_ticks = 0x7FFFFFFF; + lapic_clockevent.min_delta_ns = + clockevent_delta2ns(0xF, &lapic_clockevent); + lapic_clockevent.min_delta_ticks = 0xF; + + return 0; +} + +bool __init apic_needs_pit(void) +{ + /* + * If the frequencies are not known, PIT is required for both TSC + * and apic timer calibration. + */ + if (!tsc_khz || !cpu_khz) + return true; + + /* Is there an APIC at all or is it disabled? */ + if (!boot_cpu_has(X86_FEATURE_APIC) || disable_apic) + return true; + + /* + * If interrupt delivery mode is legacy PIC or virtual wire without + * configuration, the local APIC timer wont be set up. Make sure + * that the PIT is initialized. + */ + if (apic_intr_mode == APIC_PIC || + apic_intr_mode == APIC_VIRTUAL_WIRE_NO_CONFIG) + return true; + + /* Virt guests may lack ARAT, but still have DEADLINE */ + if (!boot_cpu_has(X86_FEATURE_ARAT)) + return true; + + /* Deadline timer is based on TSC so no further PIT action required */ + if (boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER)) + return false; + + /* APIC timer disabled? */ + if (disable_apic_timer) + return true; + /* + * The APIC timer frequency is known already, no PIT calibration + * required. If unknown, let the PIT be initialized. + */ + return lapic_timer_period == 0; +} + +static int __init calibrate_APIC_clock(void) +{ + struct clock_event_device *levt = this_cpu_ptr(&lapic_events); + u64 tsc_perj = 0, tsc_start = 0; + unsigned long jif_start; + unsigned long deltaj; + long delta, deltatsc; + int pm_referenced = 0; + + if (boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER)) + return 0; + + /* + * Check if lapic timer has already been calibrated by platform + * specific routine, such as tsc calibration code. If so just fill + * in the clockevent structure and return. + */ + if (!lapic_init_clockevent()) { + apic_printk(APIC_VERBOSE, "lapic timer already calibrated %d\n", + lapic_timer_period); + /* + * Direct calibration methods must have an always running + * local APIC timer, no need for broadcast timer. + */ + lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY; + return 0; + } + + apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n" + "calibrating APIC timer ...\n"); + + /* + * There are platforms w/o global clockevent devices. Instead of + * making the calibration conditional on that, use a polling based + * approach everywhere. + */ + local_irq_disable(); + + /* + * Setup the APIC counter to maximum. There is no way the lapic + * can underflow in the 100ms detection time frame + */ + __setup_APIC_LVTT(0xffffffff, 0, 0); + + /* + * Methods to terminate the calibration loop: + * 1) Global clockevent if available (jiffies) + * 2) TSC if available and frequency is known + */ + jif_start = READ_ONCE(jiffies); + + if (tsc_khz) { + tsc_start = rdtsc(); + tsc_perj = div_u64((u64)tsc_khz * 1000, HZ); + } + + /* + * Enable interrupts so the tick can fire, if a global + * clockevent device is available + */ + local_irq_enable(); + + while (lapic_cal_loops <= LAPIC_CAL_LOOPS) { + /* Wait for a tick to elapse */ + while (1) { + if (tsc_khz) { + u64 tsc_now = rdtsc(); + if ((tsc_now - tsc_start) >= tsc_perj) { + tsc_start += tsc_perj; + break; + } + } else { + unsigned long jif_now = READ_ONCE(jiffies); + + if (time_after(jif_now, jif_start)) { + jif_start = jif_now; + break; + } + } + cpu_relax(); + } + + /* Invoke the calibration routine */ + local_irq_disable(); + lapic_cal_handler(NULL); + local_irq_enable(); + } + + local_irq_disable(); + + /* Build delta t1-t2 as apic timer counts down */ + delta = lapic_cal_t1 - lapic_cal_t2; + apic_printk(APIC_VERBOSE, "... lapic delta = %ld\n", delta); + + deltatsc = (long)(lapic_cal_tsc2 - lapic_cal_tsc1); + + /* we trust the PM based calibration if possible */ + pm_referenced = !calibrate_by_pmtimer(lapic_cal_pm2 - lapic_cal_pm1, + &delta, &deltatsc); + + lapic_timer_period = (delta * APIC_DIVISOR) / LAPIC_CAL_LOOPS; + lapic_init_clockevent(); + + apic_printk(APIC_VERBOSE, "..... delta %ld\n", delta); + apic_printk(APIC_VERBOSE, "..... mult: %u\n", lapic_clockevent.mult); + apic_printk(APIC_VERBOSE, "..... calibration result: %u\n", + lapic_timer_period); + + if (boot_cpu_has(X86_FEATURE_TSC)) { + apic_printk(APIC_VERBOSE, "..... CPU clock speed is " + "%ld.%04ld MHz.\n", + (deltatsc / LAPIC_CAL_LOOPS) / (1000000 / HZ), + (deltatsc / LAPIC_CAL_LOOPS) % (1000000 / HZ)); + } + + apic_printk(APIC_VERBOSE, "..... host bus clock speed is " + "%u.%04u MHz.\n", + lapic_timer_period / (1000000 / HZ), + lapic_timer_period % (1000000 / HZ)); + + /* + * Do a sanity check on the APIC calibration result + */ + if (lapic_timer_period < (1000000 / HZ)) { + local_irq_enable(); + pr_warn("APIC frequency too slow, disabling apic timer\n"); + return -1; + } + + levt->features &= ~CLOCK_EVT_FEAT_DUMMY; + + /* + * PM timer calibration failed or not turned on so lets try APIC + * timer based calibration, if a global clockevent device is + * available. + */ + if (!pm_referenced && global_clock_event) { + apic_printk(APIC_VERBOSE, "... verify APIC timer\n"); + + /* + * Setup the apic timer manually + */ + levt->event_handler = lapic_cal_handler; + lapic_timer_set_periodic(levt); + lapic_cal_loops = -1; + + /* Let the interrupts run */ + local_irq_enable(); + + while (lapic_cal_loops <= LAPIC_CAL_LOOPS) + cpu_relax(); + + /* Stop the lapic timer */ + local_irq_disable(); + lapic_timer_shutdown(levt); + + /* Jiffies delta */ + deltaj = lapic_cal_j2 - lapic_cal_j1; + apic_printk(APIC_VERBOSE, "... jiffies delta = %lu\n", deltaj); + + /* Check, if the jiffies result is consistent */ + if (deltaj >= LAPIC_CAL_LOOPS-2 && deltaj <= LAPIC_CAL_LOOPS+2) + apic_printk(APIC_VERBOSE, "... jiffies result ok\n"); + else + levt->features |= CLOCK_EVT_FEAT_DUMMY; + } + local_irq_enable(); + + if (levt->features & CLOCK_EVT_FEAT_DUMMY) { + pr_warn("APIC timer disabled due to verification failure\n"); + return -1; + } + + return 0; +} + +/* + * Setup the boot APIC + * + * Calibrate and verify the result. + */ +void __init setup_boot_APIC_clock(void) +{ + /* + * The local apic timer can be disabled via the kernel + * commandline or from the CPU detection code. Register the lapic + * timer as a dummy clock event source on SMP systems, so the + * broadcast mechanism is used. On UP systems simply ignore it. + */ + if (disable_apic_timer) { + pr_info("Disabling APIC timer\n"); + /* No broadcast on UP ! */ + if (num_possible_cpus() > 1) { + lapic_clockevent.mult = 1; + setup_APIC_timer(); + } + return; + } + + if (calibrate_APIC_clock()) { + /* No broadcast on UP ! */ + if (num_possible_cpus() > 1) + setup_APIC_timer(); + return; + } + + /* + * If nmi_watchdog is set to IO_APIC, we need the + * PIT/HPET going. Otherwise register lapic as a dummy + * device. + */ + lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY; + + /* Setup the lapic or request the broadcast */ + setup_APIC_timer(); + amd_e400_c1e_apic_setup(); +} + +void setup_secondary_APIC_clock(void) +{ + setup_APIC_timer(); + amd_e400_c1e_apic_setup(); +} + +/* + * The guts of the apic timer interrupt + */ +static void local_apic_timer_interrupt(void) +{ + struct clock_event_device *evt = this_cpu_ptr(&lapic_events); + + /* + * Normally we should not be here till LAPIC has been initialized but + * in some cases like kdump, its possible that there is a pending LAPIC + * timer interrupt from previous kernel's context and is delivered in + * new kernel the moment interrupts are enabled. + * + * Interrupts are enabled early and LAPIC is setup much later, hence + * its possible that when we get here evt->event_handler is NULL. + * Check for event_handler being NULL and discard the interrupt as + * spurious. + */ + if (!evt->event_handler) { + pr_warn("Spurious LAPIC timer interrupt on cpu %d\n", + smp_processor_id()); + /* Switch it off */ + lapic_timer_shutdown(evt); + return; + } + + /* + * the NMI deadlock-detector uses this. + */ + inc_irq_stat(apic_timer_irqs); + + evt->event_handler(evt); +} + +/* + * Local APIC timer interrupt. This is the most natural way for doing + * local interrupts, but local timer interrupts can be emulated by + * broadcast interrupts too. [in case the hw doesn't support APIC timers] + * + * [ if a single-CPU system runs an SMP kernel then we call the local + * interrupt as well. Thus we cannot inline the local irq ... ] + */ +DEFINE_IDTENTRY_SYSVEC(sysvec_apic_timer_interrupt) +{ + struct pt_regs *old_regs = set_irq_regs(regs); + + ack_APIC_irq(); + trace_local_timer_entry(LOCAL_TIMER_VECTOR); + local_apic_timer_interrupt(); + trace_local_timer_exit(LOCAL_TIMER_VECTOR); + + set_irq_regs(old_regs); +} + +/* + * Local APIC start and shutdown + */ + +/** + * clear_local_APIC - shutdown the local APIC + * + * This is called, when a CPU is disabled and before rebooting, so the state of + * the local APIC has no dangling leftovers. Also used to cleanout any BIOS + * leftovers during boot. + */ +void clear_local_APIC(void) +{ + int maxlvt; + u32 v; + + /* APIC hasn't been mapped yet */ + if (!x2apic_mode && !apic_phys) + return; + + maxlvt = lapic_get_maxlvt(); + /* + * Masking an LVT entry can trigger a local APIC error + * if the vector is zero. Mask LVTERR first to prevent this. + */ + if (maxlvt >= 3) { + v = ERROR_APIC_VECTOR; /* any non-zero vector will do */ + apic_write(APIC_LVTERR, v | APIC_LVT_MASKED); + } + /* + * Careful: we have to set masks only first to deassert + * any level-triggered sources. + */ + v = apic_read(APIC_LVTT); + apic_write(APIC_LVTT, v | APIC_LVT_MASKED); + v = apic_read(APIC_LVT0); + apic_write(APIC_LVT0, v | APIC_LVT_MASKED); + v = apic_read(APIC_LVT1); + apic_write(APIC_LVT1, v | APIC_LVT_MASKED); + if (maxlvt >= 4) { + v = apic_read(APIC_LVTPC); + apic_write(APIC_LVTPC, v | APIC_LVT_MASKED); + } + + /* lets not touch this if we didn't frob it */ +#ifdef CONFIG_X86_THERMAL_VECTOR + if (maxlvt >= 5) { + v = apic_read(APIC_LVTTHMR); + apic_write(APIC_LVTTHMR, v | APIC_LVT_MASKED); + } +#endif +#ifdef CONFIG_X86_MCE_INTEL + if (maxlvt >= 6) { + v = apic_read(APIC_LVTCMCI); + if (!(v & APIC_LVT_MASKED)) + apic_write(APIC_LVTCMCI, v | APIC_LVT_MASKED); + } +#endif + + /* + * Clean APIC state for other OSs: + */ + apic_write(APIC_LVTT, APIC_LVT_MASKED); + apic_write(APIC_LVT0, APIC_LVT_MASKED); + apic_write(APIC_LVT1, APIC_LVT_MASKED); + if (maxlvt >= 3) + apic_write(APIC_LVTERR, APIC_LVT_MASKED); + if (maxlvt >= 4) + apic_write(APIC_LVTPC, APIC_LVT_MASKED); + + /* Integrated APIC (!82489DX) ? */ + if (lapic_is_integrated()) { + if (maxlvt > 3) + /* Clear ESR due to Pentium errata 3AP and 11AP */ + apic_write(APIC_ESR, 0); + apic_read(APIC_ESR); + } +} + +/** + * apic_soft_disable - Clears and software disables the local APIC on hotplug + * + * Contrary to disable_local_APIC() this does not touch the enable bit in + * MSR_IA32_APICBASE. Clearing that bit on systems based on the 3 wire APIC + * bus would require a hardware reset as the APIC would lose track of bus + * arbitration. On systems with FSB delivery APICBASE could be disabled, + * but it has to be guaranteed that no interrupt is sent to the APIC while + * in that state and it's not clear from the SDM whether it still responds + * to INIT/SIPI messages. Stay on the safe side and use software disable. + */ +void apic_soft_disable(void) +{ + u32 value; + + clear_local_APIC(); + + /* Soft disable APIC (implies clearing of registers for 82489DX!). */ + value = apic_read(APIC_SPIV); + value &= ~APIC_SPIV_APIC_ENABLED; + apic_write(APIC_SPIV, value); +} + +/** + * disable_local_APIC - clear and disable the local APIC + */ +void disable_local_APIC(void) +{ + /* APIC hasn't been mapped yet */ + if (!x2apic_mode && !apic_phys) + return; + + apic_soft_disable(); + +#ifdef CONFIG_X86_32 + /* + * When LAPIC was disabled by the BIOS and enabled by the kernel, + * restore the disabled state. + */ + if (enabled_via_apicbase) { + unsigned int l, h; + + rdmsr(MSR_IA32_APICBASE, l, h); + l &= ~MSR_IA32_APICBASE_ENABLE; + wrmsr(MSR_IA32_APICBASE, l, h); + } +#endif +} + +/* + * If Linux enabled the LAPIC against the BIOS default disable it down before + * re-entering the BIOS on shutdown. Otherwise the BIOS may get confused and + * not power-off. Additionally clear all LVT entries before disable_local_APIC + * for the case where Linux didn't enable the LAPIC. + */ +void lapic_shutdown(void) +{ + unsigned long flags; + + if (!boot_cpu_has(X86_FEATURE_APIC) && !apic_from_smp_config()) + return; + + local_irq_save(flags); + +#ifdef CONFIG_X86_32 + if (!enabled_via_apicbase) + clear_local_APIC(); + else +#endif + disable_local_APIC(); + + + local_irq_restore(flags); +} + +/** + * sync_Arb_IDs - synchronize APIC bus arbitration IDs + */ +void __init sync_Arb_IDs(void) +{ + /* + * Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1 And not + * needed on AMD. + */ + if (modern_apic() || boot_cpu_data.x86_vendor == X86_VENDOR_AMD) + return; + + /* + * Wait for idle. + */ + apic_wait_icr_idle(); + + apic_printk(APIC_DEBUG, "Synchronizing Arb IDs.\n"); + apic_write(APIC_ICR, APIC_DEST_ALLINC | + APIC_INT_LEVELTRIG | APIC_DM_INIT); +} + +enum apic_intr_mode_id apic_intr_mode __ro_after_init; + +static int __init __apic_intr_mode_select(void) +{ + /* Check kernel option */ + if (disable_apic) { + pr_info("APIC disabled via kernel command line\n"); + return APIC_PIC; + } + + /* Check BIOS */ +#ifdef CONFIG_X86_64 + /* On 64-bit, the APIC must be integrated, Check local APIC only */ + if (!boot_cpu_has(X86_FEATURE_APIC)) { + disable_apic = 1; + pr_info("APIC disabled by BIOS\n"); + return APIC_PIC; + } +#else + /* On 32-bit, the APIC may be integrated APIC or 82489DX */ + + /* Neither 82489DX nor integrated APIC ? */ + if (!boot_cpu_has(X86_FEATURE_APIC) && !smp_found_config) { + disable_apic = 1; + return APIC_PIC; + } + + /* If the BIOS pretends there is an integrated APIC ? */ + if (!boot_cpu_has(X86_FEATURE_APIC) && + APIC_INTEGRATED(boot_cpu_apic_version)) { + disable_apic = 1; + pr_err(FW_BUG "Local APIC %d not detected, force emulation\n", + boot_cpu_physical_apicid); + return APIC_PIC; + } +#endif + + /* Check MP table or ACPI MADT configuration */ + if (!smp_found_config) { + disable_ioapic_support(); + if (!acpi_lapic) { + pr_info("APIC: ACPI MADT or MP tables are not detected\n"); + return APIC_VIRTUAL_WIRE_NO_CONFIG; + } + return APIC_VIRTUAL_WIRE; + } + +#ifdef CONFIG_SMP + /* If SMP should be disabled, then really disable it! */ + if (!setup_max_cpus) { + pr_info("APIC: SMP mode deactivated\n"); + return APIC_SYMMETRIC_IO_NO_ROUTING; + } + + if (read_apic_id() != boot_cpu_physical_apicid) { + panic("Boot APIC ID in local APIC unexpected (%d vs %d)", + read_apic_id(), boot_cpu_physical_apicid); + /* Or can we switch back to PIC here? */ + } +#endif + + return APIC_SYMMETRIC_IO; +} + +/* Select the interrupt delivery mode for the BSP */ +void __init apic_intr_mode_select(void) +{ + apic_intr_mode = __apic_intr_mode_select(); +} + +/* + * An initial setup of the virtual wire mode. + */ +void __init init_bsp_APIC(void) +{ + unsigned int value; + + /* + * Don't do the setup now if we have a SMP BIOS as the + * through-I/O-APIC virtual wire mode might be active. + */ + if (smp_found_config || !boot_cpu_has(X86_FEATURE_APIC)) + return; + + /* + * Do not trust the local APIC being empty at bootup. + */ + clear_local_APIC(); + + /* + * Enable APIC. + */ + value = apic_read(APIC_SPIV); + value &= ~APIC_VECTOR_MASK; + value |= APIC_SPIV_APIC_ENABLED; + +#ifdef CONFIG_X86_32 + /* This bit is reserved on P4/Xeon and should be cleared */ + if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) && + (boot_cpu_data.x86 == 15)) + value &= ~APIC_SPIV_FOCUS_DISABLED; + else +#endif + value |= APIC_SPIV_FOCUS_DISABLED; + value |= SPURIOUS_APIC_VECTOR; + apic_write(APIC_SPIV, value); + + /* + * Set up the virtual wire mode. + */ + apic_write(APIC_LVT0, APIC_DM_EXTINT); + value = APIC_DM_NMI; + if (!lapic_is_integrated()) /* 82489DX */ + value |= APIC_LVT_LEVEL_TRIGGER; + if (apic_extnmi == APIC_EXTNMI_NONE) + value |= APIC_LVT_MASKED; + apic_write(APIC_LVT1, value); +} + +static void __init apic_bsp_setup(bool upmode); + +/* Init the interrupt delivery mode for the BSP */ +void __init apic_intr_mode_init(void) +{ + bool upmode = IS_ENABLED(CONFIG_UP_LATE_INIT); + + switch (apic_intr_mode) { + case APIC_PIC: + pr_info("APIC: Keep in PIC mode(8259)\n"); + return; + case APIC_VIRTUAL_WIRE: + pr_info("APIC: Switch to virtual wire mode setup\n"); + break; + case APIC_VIRTUAL_WIRE_NO_CONFIG: + pr_info("APIC: Switch to virtual wire mode setup with no configuration\n"); + upmode = true; + break; + case APIC_SYMMETRIC_IO: + pr_info("APIC: Switch to symmetric I/O mode setup\n"); + break; + case APIC_SYMMETRIC_IO_NO_ROUTING: + pr_info("APIC: Switch to symmetric I/O mode setup in no SMP routine\n"); + break; + } + + default_setup_apic_routing(); + + if (x86_platform.apic_post_init) + x86_platform.apic_post_init(); + + apic_bsp_setup(upmode); +} + +static void lapic_setup_esr(void) +{ + unsigned int oldvalue, value, maxlvt; + + if (!lapic_is_integrated()) { + pr_info("No ESR for 82489DX.\n"); + return; + } + + if (apic->disable_esr) { + /* + * Something untraceable is creating bad interrupts on + * secondary quads ... for the moment, just leave the + * ESR disabled - we can't do anything useful with the + * errors anyway - mbligh + */ + pr_info("Leaving ESR disabled.\n"); + return; + } + + maxlvt = lapic_get_maxlvt(); + if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */ + apic_write(APIC_ESR, 0); + oldvalue = apic_read(APIC_ESR); + + /* enables sending errors */ + value = ERROR_APIC_VECTOR; + apic_write(APIC_LVTERR, value); + + /* + * spec says clear errors after enabling vector. + */ + if (maxlvt > 3) + apic_write(APIC_ESR, 0); + value = apic_read(APIC_ESR); + if (value != oldvalue) + apic_printk(APIC_VERBOSE, "ESR value before enabling " + "vector: 0x%08x after: 0x%08x\n", + oldvalue, value); +} + +#define APIC_IR_REGS APIC_ISR_NR +#define APIC_IR_BITS (APIC_IR_REGS * 32) +#define APIC_IR_MAPSIZE (APIC_IR_BITS / BITS_PER_LONG) + +union apic_ir { + unsigned long map[APIC_IR_MAPSIZE]; + u32 regs[APIC_IR_REGS]; +}; + +static bool apic_check_and_ack(union apic_ir *irr, union apic_ir *isr) +{ + int i, bit; + + /* Read the IRRs */ + for (i = 0; i < APIC_IR_REGS; i++) + irr->regs[i] = apic_read(APIC_IRR + i * 0x10); + + /* Read the ISRs */ + for (i = 0; i < APIC_IR_REGS; i++) + isr->regs[i] = apic_read(APIC_ISR + i * 0x10); + + /* + * If the ISR map is not empty. ACK the APIC and run another round + * to verify whether a pending IRR has been unblocked and turned + * into a ISR. + */ + if (!bitmap_empty(isr->map, APIC_IR_BITS)) { + /* + * There can be multiple ISR bits set when a high priority + * interrupt preempted a lower priority one. Issue an ACK + * per set bit. + */ + for_each_set_bit(bit, isr->map, APIC_IR_BITS) + ack_APIC_irq(); + return true; + } + + return !bitmap_empty(irr->map, APIC_IR_BITS); +} + +/* + * After a crash, we no longer service the interrupts and a pending + * interrupt from previous kernel might still have ISR bit set. + * + * Most probably by now the CPU has serviced that pending interrupt and it + * might not have done the ack_APIC_irq() because it thought, interrupt + * came from i8259 as ExtInt. LAPIC did not get EOI so it does not clear + * the ISR bit and cpu thinks it has already serviced the interrupt. Hence + * a vector might get locked. It was noticed for timer irq (vector + * 0x31). Issue an extra EOI to clear ISR. + * + * If there are pending IRR bits they turn into ISR bits after a higher + * priority ISR bit has been acked. + */ +static void apic_pending_intr_clear(void) +{ + union apic_ir irr, isr; + unsigned int i; + + /* 512 loops are way oversized and give the APIC a chance to obey. */ + for (i = 0; i < 512; i++) { + if (!apic_check_and_ack(&irr, &isr)) + return; + } + /* Dump the IRR/ISR content if that failed */ + pr_warn("APIC: Stale IRR: %256pb ISR: %256pb\n", irr.map, isr.map); +} + +/** + * setup_local_APIC - setup the local APIC + * + * Used to setup local APIC while initializing BSP or bringing up APs. + * Always called with preemption disabled. + */ +static void setup_local_APIC(void) +{ + int cpu = smp_processor_id(); + unsigned int value; + + if (disable_apic) { + disable_ioapic_support(); + return; + } + + /* + * If this comes from kexec/kcrash the APIC might be enabled in + * SPIV. Soft disable it before doing further initialization. + */ + value = apic_read(APIC_SPIV); + value &= ~APIC_SPIV_APIC_ENABLED; + apic_write(APIC_SPIV, value); + +#ifdef CONFIG_X86_32 + /* Pound the ESR really hard over the head with a big hammer - mbligh */ + if (lapic_is_integrated() && apic->disable_esr) { + apic_write(APIC_ESR, 0); + apic_write(APIC_ESR, 0); + apic_write(APIC_ESR, 0); + apic_write(APIC_ESR, 0); + } +#endif + /* + * Double-check whether this APIC is really registered. + * This is meaningless in clustered apic mode, so we skip it. + */ + BUG_ON(!apic->apic_id_registered()); + + /* + * Intel recommends to set DFR, LDR and TPR before enabling + * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel + * document number 292116). So here it goes... + */ + apic->init_apic_ldr(); + +#ifdef CONFIG_X86_32 + if (apic->dest_mode_logical) { + int logical_apicid, ldr_apicid; + + /* + * APIC LDR is initialized. If logical_apicid mapping was + * initialized during get_smp_config(), make sure it matches + * the actual value. + */ + logical_apicid = early_per_cpu(x86_cpu_to_logical_apicid, cpu); + ldr_apicid = GET_APIC_LOGICAL_ID(apic_read(APIC_LDR)); + if (logical_apicid != BAD_APICID) + WARN_ON(logical_apicid != ldr_apicid); + /* Always use the value from LDR. */ + early_per_cpu(x86_cpu_to_logical_apicid, cpu) = ldr_apicid; + } +#endif + + /* + * Set Task Priority to 'accept all except vectors 0-31'. An APIC + * vector in the 16-31 range could be delivered if TPR == 0, but we + * would think it's an exception and terrible things will happen. We + * never change this later on. + */ + value = apic_read(APIC_TASKPRI); + value &= ~APIC_TPRI_MASK; + value |= 0x10; + apic_write(APIC_TASKPRI, value); + + /* Clear eventually stale ISR/IRR bits */ + apic_pending_intr_clear(); + + /* + * Now that we are all set up, enable the APIC + */ + value = apic_read(APIC_SPIV); + value &= ~APIC_VECTOR_MASK; + /* + * Enable APIC + */ + value |= APIC_SPIV_APIC_ENABLED; + +#ifdef CONFIG_X86_32 + /* + * Some unknown Intel IO/APIC (or APIC) errata is biting us with + * certain networking cards. If high frequency interrupts are + * happening on a particular IOAPIC pin, plus the IOAPIC routing + * entry is masked/unmasked at a high rate as well then sooner or + * later IOAPIC line gets 'stuck', no more interrupts are received + * from the device. If focus CPU is disabled then the hang goes + * away, oh well :-( + * + * [ This bug can be reproduced easily with a level-triggered + * PCI Ne2000 networking cards and PII/PIII processors, dual + * BX chipset. ] + */ + /* + * Actually disabling the focus CPU check just makes the hang less + * frequent as it makes the interrupt distribution model be more + * like LRU than MRU (the short-term load is more even across CPUs). + */ + + /* + * - enable focus processor (bit==0) + * - 64bit mode always use processor focus + * so no need to set it + */ + value &= ~APIC_SPIV_FOCUS_DISABLED; +#endif + + /* + * Set spurious IRQ vector + */ + value |= SPURIOUS_APIC_VECTOR; + apic_write(APIC_SPIV, value); + + perf_events_lapic_init(); + + /* + * Set up LVT0, LVT1: + * + * set up through-local-APIC on the boot CPU's LINT0. This is not + * strictly necessary in pure symmetric-IO mode, but sometimes + * we delegate interrupts to the 8259A. + */ + /* + * TODO: set up through-local-APIC from through-I/O-APIC? --macro + */ + value = apic_read(APIC_LVT0) & APIC_LVT_MASKED; + if (!cpu && (pic_mode || !value || skip_ioapic_setup)) { + value = APIC_DM_EXTINT; + apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n", cpu); + } else { + value = APIC_DM_EXTINT | APIC_LVT_MASKED; + apic_printk(APIC_VERBOSE, "masked ExtINT on CPU#%d\n", cpu); + } + apic_write(APIC_LVT0, value); + + /* + * Only the BSP sees the LINT1 NMI signal by default. This can be + * modified by apic_extnmi= boot option. + */ + if ((!cpu && apic_extnmi != APIC_EXTNMI_NONE) || + apic_extnmi == APIC_EXTNMI_ALL) + value = APIC_DM_NMI; + else + value = APIC_DM_NMI | APIC_LVT_MASKED; + + /* Is 82489DX ? */ + if (!lapic_is_integrated()) + value |= APIC_LVT_LEVEL_TRIGGER; + apic_write(APIC_LVT1, value); + +#ifdef CONFIG_X86_MCE_INTEL + /* Recheck CMCI information after local APIC is up on CPU #0 */ + if (!cpu) + cmci_recheck(); +#endif +} + +static void end_local_APIC_setup(void) +{ + lapic_setup_esr(); + +#ifdef CONFIG_X86_32 + { + unsigned int value; + /* Disable the local apic timer */ + value = apic_read(APIC_LVTT); + value |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR); + apic_write(APIC_LVTT, value); + } +#endif + + apic_pm_activate(); +} + +/* + * APIC setup function for application processors. Called from smpboot.c + */ +void apic_ap_setup(void) +{ + setup_local_APIC(); + end_local_APIC_setup(); +} + +#ifdef CONFIG_X86_X2APIC +int x2apic_mode; +EXPORT_SYMBOL_GPL(x2apic_mode); + +enum { + X2APIC_OFF, + X2APIC_DISABLED, + /* All states below here have X2APIC enabled */ + X2APIC_ON, + X2APIC_ON_LOCKED +}; +static int x2apic_state; + +static bool x2apic_hw_locked(void) +{ + u64 ia32_cap; + u64 msr; + + ia32_cap = x86_read_arch_cap_msr(); + if (ia32_cap & ARCH_CAP_XAPIC_DISABLE) { + rdmsrl(MSR_IA32_XAPIC_DISABLE_STATUS, msr); + return (msr & LEGACY_XAPIC_DISABLED); + } + return false; +} + +static void __x2apic_disable(void) +{ + u64 msr; + + if (!boot_cpu_has(X86_FEATURE_APIC)) + return; + + rdmsrl(MSR_IA32_APICBASE, msr); + if (!(msr & X2APIC_ENABLE)) + return; + /* Disable xapic and x2apic first and then reenable xapic mode */ + wrmsrl(MSR_IA32_APICBASE, msr & ~(X2APIC_ENABLE | XAPIC_ENABLE)); + wrmsrl(MSR_IA32_APICBASE, msr & ~X2APIC_ENABLE); + printk_once(KERN_INFO "x2apic disabled\n"); +} + +static void __x2apic_enable(void) +{ + u64 msr; + + rdmsrl(MSR_IA32_APICBASE, msr); + if (msr & X2APIC_ENABLE) + return; + wrmsrl(MSR_IA32_APICBASE, msr | X2APIC_ENABLE); + printk_once(KERN_INFO "x2apic enabled\n"); +} + +static int __init setup_nox2apic(char *str) +{ + if (x2apic_enabled()) { + int apicid = native_apic_msr_read(APIC_ID); + + if (apicid >= 255) { + pr_warn("Apicid: %08x, cannot enforce nox2apic\n", + apicid); + return 0; + } + if (x2apic_hw_locked()) { + pr_warn("APIC locked in x2apic mode, can't disable\n"); + return 0; + } + pr_warn("x2apic already enabled.\n"); + __x2apic_disable(); + } + setup_clear_cpu_cap(X86_FEATURE_X2APIC); + x2apic_state = X2APIC_DISABLED; + x2apic_mode = 0; + return 0; +} +early_param("nox2apic", setup_nox2apic); + +/* Called from cpu_init() to enable x2apic on (secondary) cpus */ +void x2apic_setup(void) +{ + /* + * Try to make the AP's APIC state match that of the BSP, but if the + * BSP is unlocked and the AP is locked then there is a state mismatch. + * Warn about the mismatch in case a GP fault occurs due to a locked AP + * trying to be turned off. + */ + if (x2apic_state != X2APIC_ON_LOCKED && x2apic_hw_locked()) + pr_warn("x2apic lock mismatch between BSP and AP.\n"); + /* + * If x2apic is not in ON or LOCKED state, disable it if already enabled + * from BIOS. + */ + if (x2apic_state < X2APIC_ON) { + __x2apic_disable(); + return; + } + __x2apic_enable(); +} + +static __init void x2apic_disable(void) +{ + u32 x2apic_id, state = x2apic_state; + + x2apic_mode = 0; + x2apic_state = X2APIC_DISABLED; + + if (state != X2APIC_ON) + return; + + x2apic_id = read_apic_id(); + if (x2apic_id >= 255) + panic("Cannot disable x2apic, id: %08x\n", x2apic_id); + + if (x2apic_hw_locked()) { + pr_warn("Cannot disable locked x2apic, id: %08x\n", x2apic_id); + return; + } + + __x2apic_disable(); + register_lapic_address(mp_lapic_addr); +} + +static __init void x2apic_enable(void) +{ + if (x2apic_state != X2APIC_OFF) + return; + + x2apic_mode = 1; + x2apic_state = X2APIC_ON; + __x2apic_enable(); +} + +static __init void try_to_enable_x2apic(int remap_mode) +{ + if (x2apic_state == X2APIC_DISABLED) + return; + + if (remap_mode != IRQ_REMAP_X2APIC_MODE) { + u32 apic_limit = 255; + + /* + * Using X2APIC without IR is not architecturally supported + * on bare metal but may be supported in guests. + */ + if (!x86_init.hyper.x2apic_available()) { + pr_info("x2apic: IRQ remapping doesn't support X2APIC mode\n"); + x2apic_disable(); + return; + } + + /* + * If the hypervisor supports extended destination ID in + * MSI, that increases the maximum APIC ID that can be + * used for non-remapped IRQ domains. + */ + if (x86_init.hyper.msi_ext_dest_id()) { + virt_ext_dest_id = 1; + apic_limit = 32767; + } + + /* + * Without IR, all CPUs can be addressed by IOAPIC/MSI only + * in physical mode, and CPUs with an APIC ID that cannot + * be addressed must not be brought online. + */ + x2apic_set_max_apicid(apic_limit); + x2apic_phys = 1; + } + x2apic_enable(); +} + +void __init check_x2apic(void) +{ + if (x2apic_enabled()) { + pr_info("x2apic: enabled by BIOS, switching to x2apic ops\n"); + x2apic_mode = 1; + if (x2apic_hw_locked()) + x2apic_state = X2APIC_ON_LOCKED; + else + x2apic_state = X2APIC_ON; + } else if (!boot_cpu_has(X86_FEATURE_X2APIC)) { + x2apic_state = X2APIC_DISABLED; + } +} +#else /* CONFIG_X86_X2APIC */ +void __init check_x2apic(void) +{ + if (!apic_is_x2apic_enabled()) + return; + /* + * Checkme: Can we simply turn off x2APIC here instead of disabling the APIC? + */ + pr_err("Kernel does not support x2APIC, please recompile with CONFIG_X86_X2APIC.\n"); + pr_err("Disabling APIC, expect reduced performance and functionality.\n"); + + disable_apic = 1; + setup_clear_cpu_cap(X86_FEATURE_APIC); +} + +static inline void try_to_enable_x2apic(int remap_mode) { } +static inline void __x2apic_enable(void) { } +#endif /* !CONFIG_X86_X2APIC */ + +void __init enable_IR_x2apic(void) +{ + unsigned long flags; + int ret, ir_stat; + + if (skip_ioapic_setup) { + pr_info("Not enabling interrupt remapping due to skipped IO-APIC setup\n"); + return; + } + + ir_stat = irq_remapping_prepare(); + if (ir_stat < 0 && !x2apic_supported()) + return; + + ret = save_ioapic_entries(); + if (ret) { + pr_info("Saving IO-APIC state failed: %d\n", ret); + return; + } + + local_irq_save(flags); + legacy_pic->mask_all(); + mask_ioapic_entries(); + + /* If irq_remapping_prepare() succeeded, try to enable it */ + if (ir_stat >= 0) + ir_stat = irq_remapping_enable(); + /* ir_stat contains the remap mode or an error code */ + try_to_enable_x2apic(ir_stat); + + if (ir_stat < 0) + restore_ioapic_entries(); + legacy_pic->restore_mask(); + local_irq_restore(flags); +} + +#ifdef CONFIG_X86_64 +/* + * Detect and enable local APICs on non-SMP boards. + * Original code written by Keir Fraser. + * On AMD64 we trust the BIOS - if it says no APIC it is likely + * not correctly set up (usually the APIC timer won't work etc.) + */ +static int __init detect_init_APIC(void) +{ + if (!boot_cpu_has(X86_FEATURE_APIC)) { + pr_info("No local APIC present\n"); + return -1; + } + + mp_lapic_addr = APIC_DEFAULT_PHYS_BASE; + return 0; +} +#else + +static int __init apic_verify(void) +{ + u32 features, h, l; + + /* + * The APIC feature bit should now be enabled + * in `cpuid' + */ + features = cpuid_edx(1); + if (!(features & (1 << X86_FEATURE_APIC))) { + pr_warn("Could not enable APIC!\n"); + return -1; + } + set_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC); + mp_lapic_addr = APIC_DEFAULT_PHYS_BASE; + + /* The BIOS may have set up the APIC at some other address */ + if (boot_cpu_data.x86 >= 6) { + rdmsr(MSR_IA32_APICBASE, l, h); + if (l & MSR_IA32_APICBASE_ENABLE) + mp_lapic_addr = l & MSR_IA32_APICBASE_BASE; + } + + pr_info("Found and enabled local APIC!\n"); + return 0; +} + +int __init apic_force_enable(unsigned long addr) +{ + u32 h, l; + + if (disable_apic) + return -1; + + /* + * Some BIOSes disable the local APIC in the APIC_BASE + * MSR. This can only be done in software for Intel P6 or later + * and AMD K7 (Model > 1) or later. + */ + if (boot_cpu_data.x86 >= 6) { + rdmsr(MSR_IA32_APICBASE, l, h); + if (!(l & MSR_IA32_APICBASE_ENABLE)) { + pr_info("Local APIC disabled by BIOS -- reenabling.\n"); + l &= ~MSR_IA32_APICBASE_BASE; + l |= MSR_IA32_APICBASE_ENABLE | addr; + wrmsr(MSR_IA32_APICBASE, l, h); + enabled_via_apicbase = 1; + } + } + return apic_verify(); +} + +/* + * Detect and initialize APIC + */ +static int __init detect_init_APIC(void) +{ + /* Disabled by kernel option? */ + if (disable_apic) + return -1; + + switch (boot_cpu_data.x86_vendor) { + case X86_VENDOR_AMD: + if ((boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model > 1) || + (boot_cpu_data.x86 >= 15)) + break; + goto no_apic; + case X86_VENDOR_HYGON: + break; + case X86_VENDOR_INTEL: + if (boot_cpu_data.x86 == 6 || boot_cpu_data.x86 == 15 || + (boot_cpu_data.x86 == 5 && boot_cpu_has(X86_FEATURE_APIC))) + break; + goto no_apic; + default: + goto no_apic; + } + + if (!boot_cpu_has(X86_FEATURE_APIC)) { + /* + * Over-ride BIOS and try to enable the local APIC only if + * "lapic" specified. + */ + if (!force_enable_local_apic) { + pr_info("Local APIC disabled by BIOS -- " + "you can enable it with \"lapic\"\n"); + return -1; + } + if (apic_force_enable(APIC_DEFAULT_PHYS_BASE)) + return -1; + } else { + if (apic_verify()) + return -1; + } + + apic_pm_activate(); + + return 0; + +no_apic: + pr_info("No local APIC present or hardware disabled\n"); + return -1; +} +#endif + +/** + * init_apic_mappings - initialize APIC mappings + */ +void __init init_apic_mappings(void) +{ + unsigned int new_apicid; + + if (apic_validate_deadline_timer()) + pr_info("TSC deadline timer available\n"); + + if (x2apic_mode) { + boot_cpu_physical_apicid = read_apic_id(); + return; + } + + /* If no local APIC can be found return early */ + if (!smp_found_config && detect_init_APIC()) { + /* lets NOP'ify apic operations */ + pr_info("APIC: disable apic facility\n"); + apic_disable(); + } else { + apic_phys = mp_lapic_addr; + + /* + * If the system has ACPI MADT tables or MP info, the LAPIC + * address is already registered. + */ + if (!acpi_lapic && !smp_found_config) + register_lapic_address(apic_phys); + } + + /* + * Fetch the APIC ID of the BSP in case we have a + * default configuration (or the MP table is broken). + */ + new_apicid = read_apic_id(); + if (boot_cpu_physical_apicid != new_apicid) { + boot_cpu_physical_apicid = new_apicid; + /* + * yeah -- we lie about apic_version + * in case if apic was disabled via boot option + * but it's not a problem for SMP compiled kernel + * since apic_intr_mode_select is prepared for such + * a case and disable smp mode + */ + boot_cpu_apic_version = GET_APIC_VERSION(apic_read(APIC_LVR)); + } +} + +void __init register_lapic_address(unsigned long address) +{ + mp_lapic_addr = address; + + if (!x2apic_mode) { + set_fixmap_nocache(FIX_APIC_BASE, address); + apic_printk(APIC_VERBOSE, "mapped APIC to %16lx (%16lx)\n", + APIC_BASE, address); + } + if (boot_cpu_physical_apicid == -1U) { + boot_cpu_physical_apicid = read_apic_id(); + boot_cpu_apic_version = GET_APIC_VERSION(apic_read(APIC_LVR)); + } +} + +/* + * Local APIC interrupts + */ + +/* + * Common handling code for spurious_interrupt and spurious_vector entry + * points below. No point in allowing the compiler to inline it twice. + */ +static noinline void handle_spurious_interrupt(u8 vector) +{ + u32 v; + + trace_spurious_apic_entry(vector); + + inc_irq_stat(irq_spurious_count); + + /* + * If this is a spurious interrupt then do not acknowledge + */ + if (vector == SPURIOUS_APIC_VECTOR) { + /* See SDM vol 3 */ + pr_info("Spurious APIC interrupt (vector 0xFF) on CPU#%d, should never happen.\n", + smp_processor_id()); + goto out; + } + + /* + * If it is a vectored one, verify it's set in the ISR. If set, + * acknowledge it. + */ + v = apic_read(APIC_ISR + ((vector & ~0x1f) >> 1)); + if (v & (1 << (vector & 0x1f))) { + pr_info("Spurious interrupt (vector 0x%02x) on CPU#%d. Acked\n", + vector, smp_processor_id()); + ack_APIC_irq(); + } else { + pr_info("Spurious interrupt (vector 0x%02x) on CPU#%d. Not pending!\n", + vector, smp_processor_id()); + } +out: + trace_spurious_apic_exit(vector); +} + +/** + * spurious_interrupt - Catch all for interrupts raised on unused vectors + * @regs: Pointer to pt_regs on stack + * @vector: The vector number + * + * This is invoked from ASM entry code to catch all interrupts which + * trigger on an entry which is routed to the common_spurious idtentry + * point. + */ +DEFINE_IDTENTRY_IRQ(spurious_interrupt) +{ + handle_spurious_interrupt(vector); +} + +DEFINE_IDTENTRY_SYSVEC(sysvec_spurious_apic_interrupt) +{ + handle_spurious_interrupt(SPURIOUS_APIC_VECTOR); +} + +/* + * This interrupt should never happen with our APIC/SMP architecture + */ +DEFINE_IDTENTRY_SYSVEC(sysvec_error_interrupt) +{ + static const char * const error_interrupt_reason[] = { + "Send CS error", /* APIC Error Bit 0 */ + "Receive CS error", /* APIC Error Bit 1 */ + "Send accept error", /* APIC Error Bit 2 */ + "Receive accept error", /* APIC Error Bit 3 */ + "Redirectable IPI", /* APIC Error Bit 4 */ + "Send illegal vector", /* APIC Error Bit 5 */ + "Received illegal vector", /* APIC Error Bit 6 */ + "Illegal register address", /* APIC Error Bit 7 */ + }; + u32 v, i = 0; + + trace_error_apic_entry(ERROR_APIC_VECTOR); + + /* First tickle the hardware, only then report what went on. -- REW */ + if (lapic_get_maxlvt() > 3) /* Due to the Pentium erratum 3AP. */ + apic_write(APIC_ESR, 0); + v = apic_read(APIC_ESR); + ack_APIC_irq(); + atomic_inc(&irq_err_count); + + apic_printk(APIC_DEBUG, KERN_DEBUG "APIC error on CPU%d: %02x", + smp_processor_id(), v); + + v &= 0xff; + while (v) { + if (v & 0x1) + apic_printk(APIC_DEBUG, KERN_CONT " : %s", error_interrupt_reason[i]); + i++; + v >>= 1; + } + + apic_printk(APIC_DEBUG, KERN_CONT "\n"); + + trace_error_apic_exit(ERROR_APIC_VECTOR); +} + +/** + * connect_bsp_APIC - attach the APIC to the interrupt system + */ +static void __init connect_bsp_APIC(void) +{ +#ifdef CONFIG_X86_32 + if (pic_mode) { + /* + * Do not trust the local APIC being empty at bootup. + */ + clear_local_APIC(); + /* + * PIC mode, enable APIC mode in the IMCR, i.e. connect BSP's + * local APIC to INT and NMI lines. + */ + apic_printk(APIC_VERBOSE, "leaving PIC mode, " + "enabling APIC mode.\n"); + imcr_pic_to_apic(); + } +#endif +} + +/** + * disconnect_bsp_APIC - detach the APIC from the interrupt system + * @virt_wire_setup: indicates, whether virtual wire mode is selected + * + * Virtual wire mode is necessary to deliver legacy interrupts even when the + * APIC is disabled. + */ +void disconnect_bsp_APIC(int virt_wire_setup) +{ + unsigned int value; + +#ifdef CONFIG_X86_32 + if (pic_mode) { + /* + * Put the board back into PIC mode (has an effect only on + * certain older boards). Note that APIC interrupts, including + * IPIs, won't work beyond this point! The only exception are + * INIT IPIs. + */ + apic_printk(APIC_VERBOSE, "disabling APIC mode, " + "entering PIC mode.\n"); + imcr_apic_to_pic(); + return; + } +#endif + + /* Go back to Virtual Wire compatibility mode */ + + /* For the spurious interrupt use vector F, and enable it */ + value = apic_read(APIC_SPIV); + value &= ~APIC_VECTOR_MASK; + value |= APIC_SPIV_APIC_ENABLED; + value |= 0xf; + apic_write(APIC_SPIV, value); + + if (!virt_wire_setup) { + /* + * For LVT0 make it edge triggered, active high, + * external and enabled + */ + value = apic_read(APIC_LVT0); + value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING | + APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR | + APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED); + value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING; + value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_EXTINT); + apic_write(APIC_LVT0, value); + } else { + /* Disable LVT0 */ + apic_write(APIC_LVT0, APIC_LVT_MASKED); + } + + /* + * For LVT1 make it edge triggered, active high, + * nmi and enabled + */ + value = apic_read(APIC_LVT1); + value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING | + APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR | + APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED); + value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING; + value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_NMI); + apic_write(APIC_LVT1, value); +} + +/* + * The number of allocated logical CPU IDs. Since logical CPU IDs are allocated + * contiguously, it equals to current allocated max logical CPU ID plus 1. + * All allocated CPU IDs should be in the [0, nr_logical_cpuids) range, + * so the maximum of nr_logical_cpuids is nr_cpu_ids. + * + * NOTE: Reserve 0 for BSP. + */ +static int nr_logical_cpuids = 1; + +/* + * Used to store mapping between logical CPU IDs and APIC IDs. + */ +static int cpuid_to_apicid[] = { + [0 ... NR_CPUS - 1] = -1, +}; + +bool arch_match_cpu_phys_id(int cpu, u64 phys_id) +{ + return phys_id == cpuid_to_apicid[cpu]; +} + +#ifdef CONFIG_SMP +/** + * apic_id_is_primary_thread - Check whether APIC ID belongs to a primary thread + * @apicid: APIC ID to check + */ +bool apic_id_is_primary_thread(unsigned int apicid) +{ + u32 mask; + + if (smp_num_siblings == 1) + return true; + /* Isolate the SMT bit(s) in the APICID and check for 0 */ + mask = (1U << (fls(smp_num_siblings) - 1)) - 1; + return !(apicid & mask); +} +#endif + +/* + * Should use this API to allocate logical CPU IDs to keep nr_logical_cpuids + * and cpuid_to_apicid[] synchronized. + */ +static int allocate_logical_cpuid(int apicid) +{ + int i; + + /* + * cpuid <-> apicid mapping is persistent, so when a cpu is up, + * check if the kernel has allocated a cpuid for it. + */ + for (i = 0; i < nr_logical_cpuids; i++) { + if (cpuid_to_apicid[i] == apicid) + return i; + } + + /* Allocate a new cpuid. */ + if (nr_logical_cpuids >= nr_cpu_ids) { + WARN_ONCE(1, "APIC: NR_CPUS/possible_cpus limit of %u reached. " + "Processor %d/0x%x and the rest are ignored.\n", + nr_cpu_ids, nr_logical_cpuids, apicid); + return -EINVAL; + } + + cpuid_to_apicid[nr_logical_cpuids] = apicid; + return nr_logical_cpuids++; +} + +int generic_processor_info(int apicid, int version) +{ + int cpu, max = nr_cpu_ids; + bool boot_cpu_detected = physid_isset(boot_cpu_physical_apicid, + phys_cpu_present_map); + + /* + * boot_cpu_physical_apicid is designed to have the apicid + * returned by read_apic_id(), i.e, the apicid of the + * currently booting-up processor. However, on some platforms, + * it is temporarily modified by the apicid reported as BSP + * through MP table. Concretely: + * + * - arch/x86/kernel/mpparse.c: MP_processor_info() + * - arch/x86/mm/amdtopology.c: amd_numa_init() + * + * This function is executed with the modified + * boot_cpu_physical_apicid. So, disabled_cpu_apicid kernel + * parameter doesn't work to disable APs on kdump 2nd kernel. + * + * Since fixing handling of boot_cpu_physical_apicid requires + * another discussion and tests on each platform, we leave it + * for now and here we use read_apic_id() directly in this + * function, generic_processor_info(). + */ + if (disabled_cpu_apicid != BAD_APICID && + disabled_cpu_apicid != read_apic_id() && + disabled_cpu_apicid == apicid) { + int thiscpu = num_processors + disabled_cpus; + + pr_warn("APIC: Disabling requested cpu." + " Processor %d/0x%x ignored.\n", thiscpu, apicid); + + disabled_cpus++; + return -ENODEV; + } + + /* + * If boot cpu has not been detected yet, then only allow upto + * nr_cpu_ids - 1 processors and keep one slot free for boot cpu + */ + if (!boot_cpu_detected && num_processors >= nr_cpu_ids - 1 && + apicid != boot_cpu_physical_apicid) { + int thiscpu = max + disabled_cpus - 1; + + pr_warn("APIC: NR_CPUS/possible_cpus limit of %i almost" + " reached. Keeping one slot for boot cpu." + " Processor %d/0x%x ignored.\n", max, thiscpu, apicid); + + disabled_cpus++; + return -ENODEV; + } + + if (num_processors >= nr_cpu_ids) { + int thiscpu = max + disabled_cpus; + + pr_warn("APIC: NR_CPUS/possible_cpus limit of %i reached. " + "Processor %d/0x%x ignored.\n", max, thiscpu, apicid); + + disabled_cpus++; + return -EINVAL; + } + + if (apicid == boot_cpu_physical_apicid) { + /* + * x86_bios_cpu_apicid is required to have processors listed + * in same order as logical cpu numbers. Hence the first + * entry is BSP, and so on. + * boot_cpu_init() already hold bit 0 in cpu_present_mask + * for BSP. + */ + cpu = 0; + + /* Logical cpuid 0 is reserved for BSP. */ + cpuid_to_apicid[0] = apicid; + } else { + cpu = allocate_logical_cpuid(apicid); + if (cpu < 0) { + disabled_cpus++; + return -EINVAL; + } + } + + /* + * Validate version + */ + if (version == 0x0) { + pr_warn("BIOS bug: APIC version is 0 for CPU %d/0x%x, fixing up to 0x10\n", + cpu, apicid); + version = 0x10; + } + + if (version != boot_cpu_apic_version) { + pr_warn("BIOS bug: APIC version mismatch, boot CPU: %x, CPU %d: version %x\n", + boot_cpu_apic_version, cpu, version); + } + + if (apicid > max_physical_apicid) + max_physical_apicid = apicid; + +#if defined(CONFIG_SMP) || defined(CONFIG_X86_64) + early_per_cpu(x86_cpu_to_apicid, cpu) = apicid; + early_per_cpu(x86_bios_cpu_apicid, cpu) = apicid; +#endif +#ifdef CONFIG_X86_32 + early_per_cpu(x86_cpu_to_logical_apicid, cpu) = + apic->x86_32_early_logical_apicid(cpu); +#endif + set_cpu_possible(cpu, true); + physid_set(apicid, phys_cpu_present_map); + set_cpu_present(cpu, true); + num_processors++; + + return cpu; +} + +int hard_smp_processor_id(void) +{ + return read_apic_id(); +} + +void __irq_msi_compose_msg(struct irq_cfg *cfg, struct msi_msg *msg, + bool dmar) +{ + memset(msg, 0, sizeof(*msg)); + + msg->arch_addr_lo.base_address = X86_MSI_BASE_ADDRESS_LOW; + msg->arch_addr_lo.dest_mode_logical = apic->dest_mode_logical; + msg->arch_addr_lo.destid_0_7 = cfg->dest_apicid & 0xFF; + + msg->arch_data.delivery_mode = APIC_DELIVERY_MODE_FIXED; + msg->arch_data.vector = cfg->vector; + + msg->address_hi = X86_MSI_BASE_ADDRESS_HIGH; + /* + * Only the IOMMU itself can use the trick of putting destination + * APIC ID into the high bits of the address. Anything else would + * just be writing to memory if it tried that, and needs IR to + * address APICs which can't be addressed in the normal 32-bit + * address range at 0xFFExxxxx. That is typically just 8 bits, but + * some hypervisors allow the extended destination ID field in bits + * 5-11 to be used, giving support for 15 bits of APIC IDs in total. + */ + if (dmar) + msg->arch_addr_hi.destid_8_31 = cfg->dest_apicid >> 8; + else if (virt_ext_dest_id && cfg->dest_apicid < 0x8000) + msg->arch_addr_lo.virt_destid_8_14 = cfg->dest_apicid >> 8; + else + WARN_ON_ONCE(cfg->dest_apicid > 0xFF); +} + +u32 x86_msi_msg_get_destid(struct msi_msg *msg, bool extid) +{ + u32 dest = msg->arch_addr_lo.destid_0_7; + + if (extid) + dest |= msg->arch_addr_hi.destid_8_31 << 8; + return dest; +} +EXPORT_SYMBOL_GPL(x86_msi_msg_get_destid); + +#ifdef CONFIG_X86_64 +void __init acpi_wake_cpu_handler_update(wakeup_cpu_handler handler) +{ + struct apic **drv; + + for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) + (*drv)->wakeup_secondary_cpu_64 = handler; +} +#endif + +/* + * Override the generic EOI implementation with an optimized version. + * Only called during early boot when only one CPU is active and with + * interrupts disabled, so we know this does not race with actual APIC driver + * use. + */ +void __init apic_set_eoi_write(void (*eoi_write)(u32 reg, u32 v)) +{ + struct apic **drv; + + for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) { + /* Should happen once for each apic */ + WARN_ON((*drv)->eoi_write == eoi_write); + (*drv)->native_eoi_write = (*drv)->eoi_write; + (*drv)->eoi_write = eoi_write; + } +} + +static void __init apic_bsp_up_setup(void) +{ +#ifdef CONFIG_X86_64 + apic_write(APIC_ID, apic->set_apic_id(boot_cpu_physical_apicid)); +#else + /* + * Hack: In case of kdump, after a crash, kernel might be booting + * on a cpu with non-zero lapic id. But boot_cpu_physical_apicid + * might be zero if read from MP tables. Get it from LAPIC. + */ +# ifdef CONFIG_CRASH_DUMP + boot_cpu_physical_apicid = read_apic_id(); +# endif +#endif + physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map); +} + +/** + * apic_bsp_setup - Setup function for local apic and io-apic + * @upmode: Force UP mode (for APIC_init_uniprocessor) + */ +static void __init apic_bsp_setup(bool upmode) +{ + connect_bsp_APIC(); + if (upmode) + apic_bsp_up_setup(); + setup_local_APIC(); + + enable_IO_APIC(); + end_local_APIC_setup(); + irq_remap_enable_fault_handling(); + setup_IO_APIC(); + lapic_update_legacy_vectors(); +} + +#ifdef CONFIG_UP_LATE_INIT +void __init up_late_init(void) +{ + if (apic_intr_mode == APIC_PIC) + return; + + /* Setup local timer */ + x86_init.timers.setup_percpu_clockev(); +} +#endif + +/* + * Power management + */ +#ifdef CONFIG_PM + +static struct { + /* + * 'active' is true if the local APIC was enabled by us and + * not the BIOS; this signifies that we are also responsible + * for disabling it before entering apm/acpi suspend + */ + int active; + /* r/w apic fields */ + unsigned int apic_id; + unsigned int apic_taskpri; + unsigned int apic_ldr; + unsigned int apic_dfr; + unsigned int apic_spiv; + unsigned int apic_lvtt; + unsigned int apic_lvtpc; + unsigned int apic_lvt0; + unsigned int apic_lvt1; + unsigned int apic_lvterr; + unsigned int apic_tmict; + unsigned int apic_tdcr; + unsigned int apic_thmr; + unsigned int apic_cmci; +} apic_pm_state; + +static int lapic_suspend(void) +{ + unsigned long flags; + int maxlvt; + + if (!apic_pm_state.active) + return 0; + + maxlvt = lapic_get_maxlvt(); + + apic_pm_state.apic_id = apic_read(APIC_ID); + apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI); + apic_pm_state.apic_ldr = apic_read(APIC_LDR); + apic_pm_state.apic_dfr = apic_read(APIC_DFR); + apic_pm_state.apic_spiv = apic_read(APIC_SPIV); + apic_pm_state.apic_lvtt = apic_read(APIC_LVTT); + if (maxlvt >= 4) + apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC); + apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0); + apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1); + apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR); + apic_pm_state.apic_tmict = apic_read(APIC_TMICT); + apic_pm_state.apic_tdcr = apic_read(APIC_TDCR); +#ifdef CONFIG_X86_THERMAL_VECTOR + if (maxlvt >= 5) + apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR); +#endif +#ifdef CONFIG_X86_MCE_INTEL + if (maxlvt >= 6) + apic_pm_state.apic_cmci = apic_read(APIC_LVTCMCI); +#endif + + local_irq_save(flags); + + /* + * Mask IOAPIC before disabling the local APIC to prevent stale IRR + * entries on some implementations. + */ + mask_ioapic_entries(); + + disable_local_APIC(); + + irq_remapping_disable(); + + local_irq_restore(flags); + return 0; +} + +static void lapic_resume(void) +{ + unsigned int l, h; + unsigned long flags; + int maxlvt; + + if (!apic_pm_state.active) + return; + + local_irq_save(flags); + + /* + * IO-APIC and PIC have their own resume routines. + * We just mask them here to make sure the interrupt + * subsystem is completely quiet while we enable x2apic + * and interrupt-remapping. + */ + mask_ioapic_entries(); + legacy_pic->mask_all(); + + if (x2apic_mode) { + __x2apic_enable(); + } else { + /* + * Make sure the APICBASE points to the right address + * + * FIXME! This will be wrong if we ever support suspend on + * SMP! We'll need to do this as part of the CPU restore! + */ + if (boot_cpu_data.x86 >= 6) { + rdmsr(MSR_IA32_APICBASE, l, h); + l &= ~MSR_IA32_APICBASE_BASE; + l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr; + wrmsr(MSR_IA32_APICBASE, l, h); + } + } + + maxlvt = lapic_get_maxlvt(); + apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED); + apic_write(APIC_ID, apic_pm_state.apic_id); + apic_write(APIC_DFR, apic_pm_state.apic_dfr); + apic_write(APIC_LDR, apic_pm_state.apic_ldr); + apic_write(APIC_TASKPRI, apic_pm_state.apic_taskpri); + apic_write(APIC_SPIV, apic_pm_state.apic_spiv); + apic_write(APIC_LVT0, apic_pm_state.apic_lvt0); + apic_write(APIC_LVT1, apic_pm_state.apic_lvt1); +#ifdef CONFIG_X86_THERMAL_VECTOR + if (maxlvt >= 5) + apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr); +#endif +#ifdef CONFIG_X86_MCE_INTEL + if (maxlvt >= 6) + apic_write(APIC_LVTCMCI, apic_pm_state.apic_cmci); +#endif + if (maxlvt >= 4) + apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc); + apic_write(APIC_LVTT, apic_pm_state.apic_lvtt); + apic_write(APIC_TDCR, apic_pm_state.apic_tdcr); + apic_write(APIC_TMICT, apic_pm_state.apic_tmict); + apic_write(APIC_ESR, 0); + apic_read(APIC_ESR); + apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr); + apic_write(APIC_ESR, 0); + apic_read(APIC_ESR); + + irq_remapping_reenable(x2apic_mode); + + local_irq_restore(flags); +} + +/* + * This device has no shutdown method - fully functioning local APICs + * are needed on every CPU up until machine_halt/restart/poweroff. + */ + +static struct syscore_ops lapic_syscore_ops = { + .resume = lapic_resume, + .suspend = lapic_suspend, +}; + +static void apic_pm_activate(void) +{ + apic_pm_state.active = 1; +} + +static int __init init_lapic_sysfs(void) +{ + /* XXX: remove suspend/resume procs if !apic_pm_state.active? */ + if (boot_cpu_has(X86_FEATURE_APIC)) + register_syscore_ops(&lapic_syscore_ops); + + return 0; +} + +/* local apic needs to resume before other devices access its registers. */ +core_initcall(init_lapic_sysfs); + +#else /* CONFIG_PM */ + +static void apic_pm_activate(void) { } + +#endif /* CONFIG_PM */ + +#ifdef CONFIG_X86_64 + +static int multi_checked; +static int multi; + +static int set_multi(const struct dmi_system_id *d) +{ + if (multi) + return 0; + pr_info("APIC: %s detected, Multi Chassis\n", d->ident); + multi = 1; + return 0; +} + +static const struct dmi_system_id multi_dmi_table[] = { + { + .callback = set_multi, + .ident = "IBM System Summit2", + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "IBM"), + DMI_MATCH(DMI_PRODUCT_NAME, "Summit2"), + }, + }, + {} +}; + +static void dmi_check_multi(void) +{ + if (multi_checked) + return; + + dmi_check_system(multi_dmi_table); + multi_checked = 1; +} + +/* + * apic_is_clustered_box() -- Check if we can expect good TSC + * + * Thus far, the major user of this is IBM's Summit2 series: + * Clustered boxes may have unsynced TSC problems if they are + * multi-chassis. + * Use DMI to check them + */ +int apic_is_clustered_box(void) +{ + dmi_check_multi(); + return multi; +} +#endif + +/* + * APIC command line parameters + */ +static int __init setup_disableapic(char *arg) +{ + disable_apic = 1; + setup_clear_cpu_cap(X86_FEATURE_APIC); + return 0; +} +early_param("disableapic", setup_disableapic); + +/* same as disableapic, for compatibility */ +static int __init setup_nolapic(char *arg) +{ + return setup_disableapic(arg); +} +early_param("nolapic", setup_nolapic); + +static int __init parse_lapic_timer_c2_ok(char *arg) +{ + local_apic_timer_c2_ok = 1; + return 0; +} +early_param("lapic_timer_c2_ok", parse_lapic_timer_c2_ok); + +static int __init parse_disable_apic_timer(char *arg) +{ + disable_apic_timer = 1; + return 0; +} +early_param("noapictimer", parse_disable_apic_timer); + +static int __init parse_nolapic_timer(char *arg) +{ + disable_apic_timer = 1; + return 0; +} +early_param("nolapic_timer", parse_nolapic_timer); + +static int __init apic_set_verbosity(char *arg) +{ + if (!arg) { +#ifdef CONFIG_X86_64 + skip_ioapic_setup = 0; + return 0; +#endif + return -EINVAL; + } + + if (strcmp("debug", arg) == 0) + apic_verbosity = APIC_DEBUG; + else if (strcmp("verbose", arg) == 0) + apic_verbosity = APIC_VERBOSE; +#ifdef CONFIG_X86_64 + else { + pr_warn("APIC Verbosity level %s not recognised" + " use apic=verbose or apic=debug\n", arg); + return -EINVAL; + } +#endif + + return 0; +} +early_param("apic", apic_set_verbosity); + +static int __init lapic_insert_resource(void) +{ + if (!apic_phys) + return -1; + + /* Put local APIC into the resource map. */ + lapic_resource.start = apic_phys; + lapic_resource.end = lapic_resource.start + PAGE_SIZE - 1; + insert_resource(&iomem_resource, &lapic_resource); + + return 0; +} + +/* + * need call insert after e820__reserve_resources() + * that is using request_resource + */ +late_initcall(lapic_insert_resource); + +static int __init apic_set_disabled_cpu_apicid(char *arg) +{ + if (!arg || !get_option(&arg, &disabled_cpu_apicid)) + return -EINVAL; + + return 0; +} +early_param("disable_cpu_apicid", apic_set_disabled_cpu_apicid); + +static int __init apic_set_extnmi(char *arg) +{ + if (!arg) + return -EINVAL; + + if (!strncmp("all", arg, 3)) + apic_extnmi = APIC_EXTNMI_ALL; + else if (!strncmp("none", arg, 4)) + apic_extnmi = APIC_EXTNMI_NONE; + else if (!strncmp("bsp", arg, 3)) + apic_extnmi = APIC_EXTNMI_BSP; + else { + pr_warn("Unknown external NMI delivery mode `%s' ignored\n", arg); + return -EINVAL; + } + + return 0; +} +early_param("apic_extnmi", apic_set_extnmi); |