major restructuring, prepare for smp

code/kernel/hal/hal_apic.c

@@ -0,0 +1,74 @@
+// hal_apic.c - Local APIC + I/O APIC
+#include <kernel/hal/hal_apic.h>
+#include <ntlite/ddi/hal_api.h>
+#include <stdint.h>
+
+extern HAL_API gApi;
+
+// ---- Local APIC ----
+static volatile uint32_t* gLapic = (volatile uint32_t *)0;
+#define LAPIC_REG(off)   (*(volatile uint32_t *)((uint8_t *)gLapic + (off)))
+#define LAPIC_EOI        0x0B0
+#define LAPIC_SPURIOUS   0x0F0
+#define LAPIC_ENABLE     0x100   // bit in spurious vector register
+
+// ---- I/O APIC ----
+static volatile uint32_t* gIoapic = (volatile uint32_t *)0;
+#define IOAPIC_IDX   0x00
+#define IOAPIC_DATA  0x10
+
+static uint32_t IoapicRead(uint8_t reg) {
+    *(volatile uint32_t *)((uint8_t *)gIoapic + IOAPIC_IDX) = reg;
+    return *(volatile uint32_t *)((uint8_t *)gIoapic + IOAPIC_DATA);
+}
+static void IoapicWrite(uint8_t reg, uint32_t val) {
+    *(volatile uint32_t *)((uint8_t *)gIoapic + IOAPIC_IDX) = reg;
+    *(volatile uint32_t *)((uint8_t *)gIoapic + IOAPIC_DATA) = val;
+}
+
+// IRQ n -> redirection table at register 0x10 + 2*n (low), 0x11 + 2*n (high).
+#define IOREDTBL_LO(n)  (0x10 + 2*(n))
+#define IOREDTBL_HI(n)  (0x11 + 2*(n))
+// Interrupt vector base: IRQ 0 -> vector 0x20, IRQ 1 -> 0x21, ...
+#define IRQ_VECTOR_BASE  0x20
+
+void HalApicRouteIrq(uint8_t irq) {
+    // Full initial setup of the redirection entry.
+    // Sets the vector and clears the mask bit in one write.
+    uint32_t vector = IRQ_VECTOR_BASE + irq;   // e.g. IRQ 1 -> vector 0x21
+    IoapicWrite(IOREDTBL_LO(irq), vector);     // unmasked (bit 16 = 0), edge, fixed
+    IoapicWrite(IOREDTBL_HI(irq), 0);          // deliver to LAPIC id 0
+}
+
+void HalApicMaskIrq(uint8_t irq) {
+    uint32_t lo = IoapicRead(IOREDTBL_LO(irq));
+    lo |= (1 << 16);
+    IoapicWrite(IOREDTBL_LO(irq), lo);
+}
+
+void HalApicUnmaskIrq(uint8_t irq) {
+    uint32_t lo = IoapicRead(IOREDTBL_LO(irq));
+    lo &= ~(1 << 16);   // clear mask bit
+    lo  =  (lo & ~0xFF) | (IRQ_VECTOR_BASE + irq);
+    IoapicWrite(IOREDTBL_LO(irq), lo);
+    IoapicWrite(IOREDTBL_HI(irq), 0);   // LAPIC id 0
+}
+
+void HalApicSendEoi(void) {
+    LAPIC_REG(LAPIC_EOI) = 0;
+}
+
+void HalApicInitialize(uintptr_t lapicPhys, uintptr_t ioapicPhys) {
+    gLapic  = (volatile uint32_t *)(gApi.PhysToVirt(lapicPhys));
+    gIoapic = (volatile uint32_t *)(gApi.PhysToVirt(ioapicPhys));
+
+    // Enable Local APIC, set spurious vector to 0xFF.
+    LAPIC_REG(LAPIC_SPURIOUS) = LAPIC_ENABLE | 0xFF;
+
+    // Mask all IOAPIC lines initially.
+    uint32_t maxRedir = (IoapicRead(1) >> 16) & 0xFF;
+    for (uint8_t i = 0; i <= maxRedir; i++) {
+        IoapicWrite(IOREDTBL_LO(i), (1 << 16) | (IRQ_VECTOR_BASE + i));
+        IoapicWrite(IOREDTBL_HI(i), 0);
+    }
+}