acpi - start implementing acpi

kernel/src/main.c

@@ -73,11 +73,9 @@ void kmain(void) {
 
   gdt_init(&kstack[8192]);
   idt_init();
-  fpu_activate();
-  sse_init();
-
   pmm_init();
   vmm_init();
+  
   kernel_vma_context = vma_create_context(vmm_kernel_pm);
   if (!kernel_vma_context) {
     log("kernel - vma ctx creation failed. halting\n");
@@ -86,9 +84,10 @@ void kmain(void) {
       asm("hlt");
   }
   
+  acpi_init();
   syscall_init();
-  pit_init(1000);
-  sched_init();
+  //pit_init(1000);
+  //sched_init();
   
   //vfs_init();
 

kernel/src/sys/acpi.c

@@ -3,48 +3,38 @@
 #include "sys/log.h"
 #include <mm/memop.h>
 #include <stddef.h>
+#include <stdint.h>
 #include <sys/acpi.h>
+#include <sys/errhnd/panic.h>
 
 __attribute__((
     used,
     section(".limine_requests"))) static volatile struct limine_rsdp_request
     rsdp_req = {.revision = 0, .id = LIMINE_RSDP_REQUEST};
 
-rsdp_t *rsdp;
-int acpi_available = 0;
+static int __acpi_uses_xsdt = 0;
+static void *__acpi_rsdt_ptr;
 
-int is_xsdt = 0;
-xsdt_t *xsdt;
-rsdt_t *rsdt;
-int item_count = 0;
+void *acpi_find_table(const char *name) {
+  if (!__acpi_uses_xsdt) {
+    acpi_rsdt *rsdt = (acpi_rsdt *)__acpi_rsdt_ptr;
+    uint32_t entries = (rsdt->sdt.len - sizeof(rsdt->sdt)) / 4;
 
-static int acpi_validate_rsdp(char *byte_array, size_t size) {
-  uint32_t sum = 0;
-  for (int i = 0; i < size; i++) {
-    sum += byte_array[i];
-  }
-  return (sum & 0xFF) == 0;
-}
-
-void *acpi_find_table(char *sign, int sign_size) {
-  if (!acpi_available)
-    return NULL;
-
-  if (is_xsdt) {
-    for (int i = 0; i < item_count; i++) {
-      uint64_t *lst =
-          (uint64_t *)HIGHER_HALF((uint64_t)xsdt->PointerToOtherSDT);
-      acpi_table_header_t *ptr = (acpi_table_header_t *)HIGHER_HALF(lst[i]);
-
-      if (!memcmp(ptr->Signature, sign, sign_size))
-        return (void *)ptr;
+    for (uint32_t i = 0; i < entries; i++) {
+      acpi_sdt *sdt = (acpi_sdt *)HIGHER_HALF(*((uint32_t *)rsdt->table + i));
+      if (!memcmp(sdt->sign, name, 4))
+        return (void *)sdt;
     }
-  } else {
-    for (int i = 0; i < item_count; i++) {
-      acpi_table_header_t *ptr = (acpi_table_header_t *)HIGHER_HALF(
-          (uint64_t)rsdt->PointerToOtherSDT[i]);
-      if (!memcmp(ptr->Signature, sign, sign_size))
-        return (void *)ptr;
+    return NULL;
+  }
+
+  acpi_xsdt *xsdt = (acpi_xsdt *)__acpi_rsdt_ptr;
+  uint32_t entries = (xsdt->sdt.len - sizeof(xsdt->sdt)) / 8;
+
+  for (uint32_t i = 0; i < entries; i++) {
+    acpi_sdt *sdt = (acpi_sdt *)HIGHER_HALF(*((uint64_t *)xsdt->table + i));
+    if (!memcmp(sdt->sign, name, 4)) {
+      return (void *)sdt;
     }
   }
 
@@ -52,44 +42,17 @@ void *acpi_find_table(char *sign, int sign_size) {
 }
 
 void acpi_init() {
-  rsdp_t *rsdp = (rsdp_t *)HIGHER_HALF(rsdp_req.response->address);
+  acpi_rsdp *rsdp = (acpi_rsdp *)rsdp_req.response->address;
 
-  if (!rsdp) {
-    log("acpi - not available: RSDP is NULL!\n");
+  if (memcmp(rsdp->sign, "RSD PTR", 7))
+    panic("acpi: Invalid RSDP signature!");
+
+  if (rsdp->revision != 0) {
+    __acpi_uses_xsdt = 1;
+    acpi_xsdp *xsdp = (acpi_xsdp *)rsdp;
+    __acpi_rsdt_ptr = (acpi_xsdt *)HIGHER_HALF((uint64_t)xsdp->xsdt_addr);
     return;
   }
 
-  if (rsdp->rev < 2) {
-    if (!acpi_validate_rsdp((char *)rsdp, sizeof(rsdp_t))) {
-      log("acpi - not available: Was the RSDP hijacked?\n");
-      return;
-    }
-    rsdt = (rsdt_t *)HIGHER_HALF((uint64_t)rsdp->rsdt_addr);
-    log("acpi - RSDT found at %p\n", rsdt);
-    item_count = (rsdt->h.Length - sizeof(acpi_table_header_t)) / 4;
-    log("acpi - RSDT contains %d entries\n", item_count);
-  } else {
-    is_xsdt = 1;
-    if (!acpi_validate_rsdp((char *)rsdp, sizeof(xsdp_t))) {
-      log("acpi - not available: Was the XSDP hijacked?\n");
-      return;
-    }
-
-    xsdt = (xsdt_t *)HIGHER_HALF((uint64_t)((xsdp_t *)rsdp)->xsdt_addr);
-    log("acpi - XSDT found at %p\n", xsdt);
-    item_count = (xsdt->h.Length - sizeof(acpi_table_header_t)) / 8;
-    log("acpi - XSDT contains %d entries\n", item_count);
-  }
-
-  acpi_available = 1;
-
-  void *fadt = acpi_find_table("FACP", 4);
-  if (!fadt) {
-    log("acpi - FADT not found\n");
-    acpi_available = 0;
-    return;
-  } else {
-    log("acpi - FADT found at %p\n", fadt);
-    log("acpi - ACPI initialized successfully\n");
-  }
+  __acpi_rsdt_ptr = (acpi_rsdt *)HIGHER_HALF((uint64_t)rsdp->rsdt_addr);
 }

kernel/src/sys/acpi.h

@@ -5,47 +5,48 @@
 #define ACPI_RSDP_SIGNATURE "RSD PTR "
 #define ACPI_RSDP_SIGNATURE_LEN 7
 
-typedef struct __acpi_table_header {
-  char Signature[4];
-  uint32_t Length;
-  uint8_t Revision;
-  uint8_t Checksum;
-  char OEMID[6];
-  char OEMTableID[8];
-  uint32_t OEMRevision;
-  uint32_t CreatorID;
-  uint32_t CreatorRevision;
-} acpi_table_header_t;
-
-typedef struct __rsdp {
-  char signature[8];
-  uint8_t chksum;
-  char oemid[6];
-  uint8_t rev;
+typedef struct {
+  char sign[8];
+  uint8_t checksum;
+  char oem_id[6];
+  uint8_t revision;
   uint32_t rsdt_addr;
-} __attribute__((packed)) rsdp_t;
+} __attribute__((packed)) acpi_rsdp;
 
-typedef struct __xsdp {
-  char signature[8];
-  uint8_t chksum;
-  char oemid[6];
-  uint8_t rev;
-  uint32_t rsdt_addr; // deprecated since version 2.0
+typedef struct {
+  char sign[8];
+  uint8_t checksum;
+  char oem_id[6];
+  uint8_t revision;
+  uint32_t resv;
 
-  uint32_t len;
+  uint32_t length;
   uint64_t xsdt_addr;
-  uint8_t chksum_ex;
-  uint8_t reserved[3];
-} __attribute__((packed)) xsdp_t;
+  uint8_t extended_checksum;
+  uint8_t resv1[3];
+} __attribute__((packed)) acpi_xsdp;
 
-typedef struct __rsdt {
-  acpi_table_header_t h;
-  uint32_t *PointerToOtherSDT;
-} rsdt_t;
+typedef struct {
+  char sign[4];
+  uint32_t len;
+  uint8_t revision;
+  uint8_t checksum;
+  char oem_id[6];
+  char oem_table_id[8];
+  uint32_t oem_revision;
+  uint32_t creator_id;
+  uint32_t creator_revision;
+} __attribute__((packed)) acpi_sdt;
 
-typedef struct __xsdt {
-  acpi_table_header_t h;
-  uint64_t *PointerToOtherSDT;
-} xsdt_t;
+typedef struct {
+  acpi_sdt sdt;
+  char table[];
+} acpi_rsdt;
 
+typedef struct {
+  acpi_sdt sdt;
+  char table[];
+} acpi_xsdt;
+
+void *acpi_find_table(const char *name);
 void acpi_init();

kernel/src/sys/arch/x86_64/idt.c

@@ -39,14 +39,13 @@ void idt_init() {
   idt_set_descriptor(vector, isr_stub_table[vector], 0xEE);
   vectors[vector] = 1;
 
-  pic_init();
-  pic_unmask_irq(1);
-  pic_unmask_irq(8);
+  // Do not use the legacy PIC.
+  //pic_init();
+  //pic_unmask_irq(1);
+  //pic_unmask_irq(8);
 
   __asm__ volatile("lidt %0" : : "m"(idtr)); // load the new IDT
   __asm__ volatile("sti");                   // set the interrupt flag
 
-  // logln(progress, "kinit stage 1", "IDT initialized! Time to receive
-  // interrupts!\n");
   log("idt - initialized\n");
 }