/* SPDX-License-Identifier: GPL-2.0-only */ #include #include #include #include #include #include #include void enable_lapic(void) { msr_t msr; msr = rdmsr(LAPIC_BASE_MSR); msr.hi &= 0xffffff00; msr.lo &= ~LAPIC_BASE_MSR_ADDR_MASK; msr.lo |= LAPIC_DEFAULT_BASE; msr.lo |= LAPIC_BASE_MSR_ENABLE; wrmsr(LAPIC_BASE_MSR, msr); printk(BIOS_INFO, "Setting up local APIC 0x%x\n", lapicid()); } void disable_lapic(void) { msr_t msr; msr = rdmsr(LAPIC_BASE_MSR); msr.lo &= ~LAPIC_BASE_MSR_ENABLE; wrmsr(LAPIC_BASE_MSR, msr); } uintptr_t cpu_get_lapic_addr(void) { return LAPIC_DEFAULT_BASE; } /* See if I need to initialize the local APIC */ static int need_lapic_init(void) { return CONFIG(SMP) || CONFIG(IOAPIC); } static void lapic_virtual_wire_mode_init(void) { /* * Set Task Priority to 'accept all'. */ lapic_update32(LAPIC_TASKPRI, ~LAPIC_TPRI_MASK, 0); /* Set spurious interrupt vector to 0 and keep LAPIC enabled to be able to clear LVT register mask bits. */ lapic_update32(LAPIC_SPIV, ~LAPIC_VECTOR_MASK, LAPIC_SPIV_ENABLE); /* Put the local APIC in virtual wire mode */ uint32_t mask = LAPIC_LVT_MASKED | LAPIC_LVT_LEVEL_TRIGGER | LAPIC_INPUT_POLARITY | LAPIC_DELIVERY_MODE_MASK; if (boot_cpu()) lapic_update32(LAPIC_LVT0, ~mask, LAPIC_DELIVERY_MODE_EXTINT); else lapic_update32(LAPIC_LVT0, ~mask, LAPIC_LVT_MASKED | LAPIC_DELIVERY_MODE_EXTINT); lapic_update32(LAPIC_LVT1, ~mask, LAPIC_DELIVERY_MODE_NMI); } void setup_lapic(void) { /* Enable the local APIC */ if (need_lapic_init()) enable_lapic(); else if (!CONFIG(UDELAY_LAPIC)) disable_lapic(); /* This programming is for PIC mode i8259 interrupts to be delivered to CPU while LAPIC is enabled. */ if (need_lapic_init()) lapic_virtual_wire_mode_init(); }