108 lines
2.4 KiB
C

#include <cpu.h>
#include <memory.h>
#include <string.h>
#include <debug.h>
// ACPI Specification:
// https://uefi.org/sites/default/files/resources/ACPI_6_3_final_Jan30.pdf
struct rsdp { // 5.2.5.3
char signature[8];
uint8_t checksum;
char OEMID[6];
uint8_t revision;
uint32_t rsdt_p;
uint8_t _[14]; // Fields for revision >= 2
}__attribute__((packed));
struct sdt {
char signature[4];
uint32_t length;
uint8_t _[28];
uint32_t data[];
}__attribute__((packed));
// MADT (5.2.12)
#define MADT_TYPE_LAPIC 0
#define MADT_TYPE_IOAPIC 1
#define MADT_TYPE_ISO 2
struct madt_field {
uint8_t type;
uint8_t length;
union {
struct { // Processor Local APIC (5.2.12.2)
uint8_t id;
uint8_t apic;
uint32_t flags;
}__attribute__((packed)) lapic;
struct { // I/O APIC (5.2.12.3)
uint8_t id;
uint8_t reserved;
uint32_t address;
uint32_t base;
}__attribute__((packed)) ioapic;
struct { // Interrupt source override (5.2.12.5)
uint8_t bus;
uint8_t source;
uint32_t interrupt;
uint16_t flags;
}__attribute__((packed)) iso;
};
}__attribute__((packed));
struct madt_header {
uint32_t controllerAddress;
uint32_t flags;
struct madt_field fields[];
}__attribute__((packed));
static void madt_parse(struct madt_header *madt, size_t length)
{
int cpu_i=0;
for(struct madt_field *f = madt->fields;
(size_t)f <= (size_t)madt + length;
f = incptr(f, f->length)
) {
switch(f->type) {
case MADT_TYPE_LAPIC: {
struct cpu *cpu = P2V(pmm_alloc());
cpus[cpu_i++] = cpu;
cpu->id = f->lapic.id;
cpu->apic_id = f->lapic.apic;
cpu->flags = f->lapic.flags;
break;
}
case MADT_TYPE_IOAPIC: {
ioapic.id = f->ioapic.id;
ioapic.addr = f->ioapic.address;
ioapic.base = f->ioapic.base;
break;
}
case MADT_TYPE_ISO: {
irq_redirects[f->iso.source] = f->iso.interrupt;
break;
}
default:
}
}
}
void acpi_parse(void *_rsdp) {
struct rsdp *rsdp = _rsdp;
struct sdt *rsdt = P2V(rsdp->rsdt_p);
int rsdt_entries = (rsdt->length - sizeof(struct sdt))/sizeof(uint32_t);
for(int i = 0; i < rsdt_entries; i++) {
struct sdt *h = P2V(rsdt->data[i]);
if(h->length == 0) continue;
if(!strncmp(h->signature, "APIC", 4)) { // 5.2.12
madt_parse(P2V(h->data), h->length - sizeof(struct sdt));
}
}
}