Added apic init

src/acpi.c

@@ -4,38 +4,14 @@
 #include "../include/limine.h"
 
 // credit to dreamportdev's OSDev-Notes and the OSDev Wiki for table layouts
+//
 
 #include "acpi.h"
 #define RSDT_SIGNATURE "RSDT"
 #define XSDT_SIGNATURE "XSDT"
 
-bool rsdp_validate(const u8* data) {
-  if(memcmp(data, (const u8*)RSDP_SIGNATURE, 8) != 0) {
-    /* to debug in memcmp is broken somehow */
-    if(data[0] == 'R' && data[1] == 'S' && data[2] == 'D' && data[3] == 'T' && data[4] == ' ') {
-      printn((const char*)data, 8);
-    }
-    return false;
-  }
-
-  struct acpi_rsdp_header* head = (struct acpi_rsdp_header*)data;
-  size_t len = sizeof(struct acpi_rsdp_header);
-  len -= (head->revision == 2) * sizeof(u32) + sizeof(u64) + sizeof(u8) + sizeof(u8[3]);
-  u32 sum_to_zero = 0;
-  for(size_t i = 0; i < len; i++) {
-    sum_to_zero += data[i];
-  }
-
-  return (sum_to_zero & 0xFF) == 0;
-}
-
-static bool use_xsdt = false;
 
 static struct acpi_rsdt* rsdt;
-static struct acpi_xsdt* xsdt;
-
-struct acpi_sdt_header* acpi_get_header(size_t n) {
-  return (struct acpi_sdt_header*) (use_xsdt? xsdt->addrs[n] : (u64)rsdt->addrs[n]);
-}
 
 struct acpi_rsdp_header* rsdp; 
+

src/acpi.h

@@ -11,15 +11,21 @@ pstruct acpi_rsdp_header {
   u8 checksum;
   u8 OEMID[6];
   u8 revision;
-  u32 addr32_depr;
+  /*
+  union {
+    struct acpi_rsdt* rsdt :32;
+    struct acpi_xsdt* xsdt :32;
+  } ptr;
+  */
+  u32 ptr32;
   // v2
   u32 len;
-  u64 addr;
+  u64 ptr64;
   u8 extended_checksum;
   u8 resv[3];
 };
 
-struct acpi_sdt_header {
+struct acpi_rsdt {
   u8 signature[4];
   u32 len;
   u8 revision;
@@ -29,18 +35,10 @@ struct acpi_sdt_header {
   u32 OEM_revision;
   u32 creator_id;
   u32 creator_revision;
-};
-
-struct acpi_rsdt {
-  // signature == "RSDT"
-  struct acpi_sdt_header header;
-  u32 addrs[];
-};
-
-struct acpi_xsdt {
-  // signature == "XSDT"
-  struct acpi_rsdp_header header;
-  u64 addrs[];
+  union {
+    u32 addrs32[];
+    u64 addrs64[];
+  };
 };
 
 extern struct acpi_rsdp_header* rsdp; 

src/apic.c

@@ -0,0 +1,73 @@
+#include "common.h"
+#include "print.h"
+
+// stub of a PIC layout, we don't need the whole thing
+// as we only care about initializing it to disable it
+enum {
+  PIC_COMM_MASTER = 0x20,
+  PIC_COMM_SLAVE = 0x21,
+  PIC_DATA_MASTER = 0xA0,
+  PIC_DATA_SLAVE = 0xA1,
+};
+
+static void pic_disable() {
+  outb(PIC_DATA_MASTER, ~0);
+  outb(PIC_DATA_SLAVE, ~0);
+}
+
+static inline u64 rdmsr(u32 msr) {
+  u32 hi, lo;
+  asm volatile (
+    "rdmsr"
+    : "=a"(lo), "=d"(hi)
+    : "c"(msr)
+  );
+
+  return (((u64)hi) << 32) | (u64)lo;
+}
+
+static inline void wrmsr(u32 msr, u64 val) {
+  u32 eax = (u32) val;
+  u32 edx = (u32) (val >> 32);
+  asm volatile (
+    "wrmsr"
+    :
+    : "c"(msr), "a" (eax), "d" (edx)
+  );
+}
+
+
+static u64 apic_base;
+
+u64 apic_get_local_base() {
+  const u8 APIC_BASE_MSR = 0x1B;
+
+  u64 msr = rdmsr(APIC_BASE_MSR);
+
+  return (apic_base = (msr & 0xfffff000));
+}
+
+static u64 apic_set_local_base(u64 base) {
+  const u8 APIC_BASE_MSR = 0x1B;
+  
+  wrmsr(APIC_BASE_MSR, base & 0xfffff000);
+
+  return base & 0xfffff000;
+}
+
+static u32* apic_reg(u32 reg) {
+  return (u32*) (apic_base + reg);
+}
+
+void apic_enable() {
+  pic_disable();
+  print("\nPIC Disabled\n");
+  apic_set_local_base(apic_get_local_base());
+  volatile u32* reg = apic_reg(0xF0);
+  print("Local Base Set\nReg 0xF0 at 0x");
+  print64((u64) reg);
+  // set enable flag
+  *reg = (*reg | 0x100);
+  print("\nReg written\n");
+}
+

src/common.h

@@ -23,6 +23,16 @@ static inline void INT(int n) {
     );
 }
 
+static inline void outb(u16 port, u8 value) {
+    asm volatile ("outb %0, %1" : : "a"(value), "Nd"(port));
+}
+static inline void outw(u16 port, u16 value) {
+    asm volatile ("outw %0, %1" : : "a"(value), "Nd"(port));
+}
+static inline void outd(u16 port, u32 value) {
+    asm volatile ("outl %0, %1" : : "a"(value), "Nd"(port));
+}
+
 
 void* memcpy(void* restrict dst, const void* src, size_t n);
 void* memset(void* s, int c, size_t n);

src/int.c

@@ -29,8 +29,6 @@ enum INT_DESC_FLAGS {
 
 #define CODE64_SELECTOR 0x28
 
-static int cnt = 0;
-
 struct int_desc idt[256];
 
 void set_idt(u8 vect, void* handler, u8 dpl) {

src/main.c

@@ -168,6 +168,9 @@ void print_memmap_entry(struct limine_memmap_entry* entry) {
 
 
 
+u32 apic_get_local_base();
+void apic_enable();
+
 void kmain() {
   if(LIMINE_BASE_REVISION_SUPPORTED(limine_base_revision) == false) {
     hang();
@@ -212,6 +215,31 @@ void kmain() {
   print("With signature: ");
   printn((char*)rsdp->signature, sizeof(rsdp->signature));
 
+  print(" v");
+  print8(rsdp->revision);
+  print("\nRSDT at 0x");
+  struct acpi_rsdt* rsdt =
+    (struct acpi_rsdt*)(
+      (rsdp->revision? rsdp->ptr64:rsdp->ptr32) + hhdm_offset
+    );
+  print64((u64)rsdt);
+  print("\nSDT Signature: ");
+
+
+  printn((const char*) rsdt->signature, sizeof(rsdt->signature));
+  print("\nAPIC Local Base: ");
+
+  /* I should check cpuid to ensure its supported but it will
+   * be for my machines ;^) */
+  /* APIC stuff */
+  u32 r = 0xDEADBEEF;
+  r = apic_get_local_base();
+  print32(r);
+
+  apic_enable();
+
+  print("\nAPIC Enabled");
+  
   hang();
   
 }