parsing RSDP & MADT

2 files changed, 140 insertions, 0 deletions

diff --git a/kernel/src/apic/madt.c b/kernel/src/apic/madt.c
new file mode 100644
index 0000000..b88b788
--- /dev/null
+++ b/kernel/src/apic/madt.c
@@ -0,0 +1,72 @@
+#include <madt.h>
+#include <heap.h>
+#include <libk/string.h>
+#include <libk/stdio.h>
+
+void parse_madt()
+{
+	uint64_t* madt_addr = find_sys_table_addr("APIC");
+
+	if (madt_addr == NULL) {
+		printf("MADT NOT FOUND\n");
+		return;
+	}
+
+	struct MADT* madt = (struct MADT*)kalloc(sizeof(struct MADT));
+	memcpy(madt, madt_addr, sizeof(struct MADT));
+
+	for (size_t curr_size = sizeof(struct MADT); curr_size < madt->h.Length;) {
+		struct MADT_type_header* m = (struct MADT_type_header*)kalloc(sizeof(struct MADT_type_header));
+		memcpy(m, (uint64_t*)((uint64_t)madt_addr + (uint64_t)curr_size), sizeof(struct MADT_type_header));
+		uint8_t type = m->type;
+		uint8_t len = m->len;
+		kfree(m);
+
+		if (type == 0) {
+			// Processor Local APIC
+			struct MADT_cpu_local_apic* cpu = (struct MADT_cpu_local_apic*)kalloc(sizeof(struct MADT_cpu_local_apic));
+			memcpy(cpu, (uint64_t*)((uint64_t)madt_addr + (uint64_t)curr_size), sizeof(struct MADT_cpu_local_apic));
+
+			printf("found cpu: acpi_id: 0x%x, apic_id: 0x%x, flags: 0x%x\n", cpu->acpi_id, cpu->apic_id, cpu->flags);
+			kfree(cpu);
+		} else if (type == 1) {
+			// I/O APIC
+			struct MADT_io_apic* io = (struct MADT_io_apic*)kalloc(sizeof(struct MADT_io_apic));
+			memcpy(io, (uint64_t*)((uint64_t)madt_addr + (uint64_t)curr_size), sizeof(struct MADT_io_apic));
+
+			printf("found io: apic_id: 0x%x, addr: 0x%x, int_base: 0x%x\n", io->apic_id, io->io_apic_addr, io->int_base);
+			kfree(io);
+		} else if (type == 2) {
+			// IO/APIC Interrupt Source Override
+			struct MADT_io_apic_int* io_apic_int = (struct MADT_io_apic_int*)kalloc(sizeof(struct MADT_io_apic_int));
+			memcpy(io_apic_int, (uint64_t*)((uint64_t)madt_addr + (uint64_t)curr_size), sizeof(struct MADT_io_apic_int));
+
+			printf("found io_apic_int: bus: 0x%x, irq_source: 0x%x, global_sys_int: 0x%x, flags: 0x%x\n", io_apic_int->bus_source, io_apic_int->irq_source, io_apic_int->global_sys_int, io_apic_int->flags);
+			kfree(io_apic_int);
+		} else if (type == 3) {
+			// IO/APIC Non-maskable interrupt source
+			printf("MADT entry of type %d\n", type);
+		} else if (type == 4) {
+			// Local APIC Non-maskable interrupts
+			struct MADT_lapic_nmi* lapic_nmi = (struct MADT_lapic_nmi*)kalloc(sizeof(struct MADT_lapic_nmi));
+			memcpy(lapic_nmi, (uint64_t*)((uint64_t)madt_addr + (uint64_t)curr_size), sizeof(struct MADT_lapic_nmi));
+
+			printf("found lapic_nmi: acpi_cpu_id: 0x%x, flags: 0x%x, lint: 0x%x\n", lapic_nmi->acpi_cpu_id, lapic_nmi->flags, lapic_nmi->lint);
+			kfree(lapic_nmi);
+		} else if (type == 5) {
+			// Local APIC Address Override
+			struct MADT_lapic_addr* lapic_addr = (struct MADT_lapic_addr*)kalloc(sizeof(struct MADT_lapic_addr));
+			memcpy(lapic_addr, (uint64_t*)((uint64_t)madt_addr + (uint64_t)curr_size), sizeof(struct MADT_lapic_addr));
+
+			printf("found lapic: addr: 0x%x\n", lapic_addr->phys_addr);
+			kfree(lapic_addr);
+		} else if (type == 9) {
+			// Processor Local x2APIC
+			printf("MADT entry of type %d\n", type);
+		} else {
+			// ERROR
+			printf("ERROR: MADT entry of type %d\n", type);
+		}
+		curr_size += len;
+	}
+}
diff --git a/kernel/src/apic/rsdp.c b/kernel/src/apic/rsdp.c
new file mode 100644
index 0000000..ebecd66
--- /dev/null
+++ b/kernel/src/apic/rsdp.c
@@ -0,0 +1,68 @@
+#include <rsdp.h>
+#include <heap.h>
+#include <paging.h>
+#include <libk/string.h>
+#include <libk/stdio.h>
+
+uint64_t* find_rsdp()
+{
+	map_addr(0x0, 0x0, FLAG_PRESENT);
+	const char* rsdp_cs = "RSD PTR ";
+	for (uint64_t i = 0x10; i < 0x100000; i += 0x10) {
+		char *x = (char*)i;
+		uint8_t ind = 1;
+		for (size_t j = 0; j < strlen(rsdp_cs); j++) {
+			if (rsdp_cs[j] != x[j]) {
+				ind = 0;
+				break;
+			}
+		}
+		if (ind) {
+			return (uint64_t*)i;
+		}
+	}
+	return NULL;
+}
+
+uint64_t* find_sys_table_addr(const char* signature)
+{
+	uint64_t* rsdp = find_rsdp();
+
+	if (rsdp == NULL) {
+		printf("RSDP NOT FOUND\n");
+		return NULL;
+	}
+
+	struct RSDP_descriptor* rsdp_desc = (struct RSDP_descriptor*)rsdp;
+	map_addr(rsdp_desc->RsdtAddress, rsdp_desc->RsdtAddress, FLAG_PRESENT);
+
+	struct ACPI_header* rsdt = (struct ACPI_header*)kalloc(sizeof(struct ACPI_header));
+	memcpy(rsdt, (uint64_t*)(uint64_t)rsdp_desc->RsdtAddress, sizeof(struct ACPI_header));
+
+	uint32_t entries = (rsdt->Length - (uint32_t)sizeof(struct ACPI_header)) / 4;
+
+	for (size_t i = 0; i < entries; i++) {
+		uint32_t na_addr = (uint32_t)rsdp_desc->RsdtAddress + (uint32_t)sizeof(struct ACPI_header) + (uint32_t)i * 4;
+		uint32_t addr;
+		memcpy(&addr, (uint64_t*)(uint64_t)na_addr, 4);
+
+		struct ACPI_header* t = (struct ACPI_header*)kalloc(sizeof(struct ACPI_header));
+		memcpy(t, (uint64_t*)(uint64_t)addr, sizeof(struct ACPI_header));
+
+		int ind = 1;
+		for (size_t j = 0; j < 4; j++) {
+			if (t->Signature[j] != signature[j])
+				ind = 0;
+		}
+		if (ind) {
+			kfree(t);
+			kfree(rsdt);
+			return (uint64_t*)(uint64_t)addr;
+		}
+
+		kfree(t);
+	}
+
+	kfree(rsdt);
+	return NULL;
+}