1 files changed, 145 insertions, 34 deletions

diff --git a/src/kernel/acpi.c b/src/kernel/acpi.c
index 0c22fe4..e5a6e4d 100644
--- a/src/kernel/acpi.c
+++ b/src/kernel/acpi.c
@@ -1,58 +1,169 @@
 #include <acpi.h>
 #include <stdint.h>
 #include <printf.h>
+#include <kernel.h>
+#include <stdbool.h>
+#include <kernel.h>
+#include <io.h>
+#include <int.h>
+#include <libc.h>
+#include <panic.h>
 
-static int RSDP_verify(void *rsdp_pointer) {
-  printf("Verifying potential RSDP at address 0x%p... ", rsdp_pointer);  
-  union rsdp_t *rsdp = rsdp_pointer;
+
+//finding rsdp
+typedef struct rsdp {
+  char sig[8];
+  uint8_t checksum;
+  char OEMID[6];
+  uint8_t revision;
+  uint32_t rsdt;
+
+  //these only exist on REV > 1
+  uint32_t len;
+  uint64_t xsdt;
+  uint8_t extended_checksum;
+  uint8_t reserved[3]; 
+
+} __attribute__((packed)) root_sdp;
+
+
+//root descriptor SDTs
+struct rsdt {
+  sdt_head header;
+  uint32_t sdt_pointers[];
+} __attribute__((packed));
+
+struct xsdt {
+  sdt_head header;
+  uint64_t sdt_pointers[];
+} __attribute__((packed));
+
+root_sdp *rsdp;
+
+
+
+void debug_acpi() {
+  sdt_head *sdt;
+  int sdt_i, sdt_cnt;
+
+  if(rsdp->revision) {
+    struct xsdt *root = PHYS_TO_VIRT(rsdp->xsdt);
+    sdt_cnt = (root->header.length - sizeof(root->header)) / 8;
+    printf("sdts found in apic headers: %i\n", sdt_cnt);
+    for(sdt_i = 0; sdt_i < sdt_cnt; sdt_i++) {
+      sdt = PHYS_TO_VIRT(root->sdt_pointers[sdt_i]);
+      printf("ACPI debug:%.4s\n", sdt->sig);
+    }
+  }
+  else {
+    struct rsdt *root = PHYS_TO_VIRT((uint64_t)rsdp->rsdt);
+    sdt_cnt = (root->header.length - sizeof(root->header)) / 4;
+    printf("sdts found in apic headers: %i\n", sdt_cnt);
+    for(sdt_i = 0; sdt_i < sdt_cnt; sdt_i++) {
+      sdt = PHYS_TO_VIRT((uint64_t)root->sdt_pointers[sdt_i]);
+      printf("ACPI debug:%.4s\n", sdt->sig);
+    }
+  }
+}
+
+//TODO clean up confusing variable name rsdt
+void *find_sdt(int type) {
+  char sig[4]; 
+  sdt_head *sdt;
+  int sdt_i, sdt_cnt;
+
+  //If we never need to expand this, then you can clean it up.
+  switch(type) {
+    case SDT_MADT:
+      strcpy(sig, "APIC");
+      break;
+    case SDT_HPET:
+      strcpy(sig, "HPET");
+      break;
+  }
+
+  if(rsdp->revision) {
+    struct xsdt *root = PHYS_TO_VIRT(rsdp->xsdt);
+    sdt_cnt = (root->header.length - sizeof(root->header)) / 8;
+    for(sdt_i = 0; sdt_i < sdt_cnt - 1; sdt_i++) {
+      sdt = PHYS_TO_VIRT((uint64_t)root->sdt_pointers[sdt_i]);
+      if(!(strncmp(sdt->sig, sig, 4))) {
+        return sdt;
+      }
+    }
+  }
+  else {
+    struct rsdt *root = PHYS_TO_VIRT((uint64_t)rsdp->rsdt);
+    sdt_cnt = (root->header.length - sizeof(root->header)) / 4;
+    for(sdt_i = 0; sdt_i < sdt_cnt - 1; sdt_i++) {
+      sdt = PHYS_TO_VIRT((uint64_t)root->sdt_pointers[sdt_i]);
+      if(!(strncmp(sdt->sig, sig, 4))) {
+        return sdt;
+      }
+    }
+  }
+  return 0;
+}
+
+bool verify_sdt(sdt_head *sdt) {
   uint8_t checksum = 0;
-  char *rsdp_csm_ptr = rsdp_pointer; 
+  for(int i = 0; i < sdt->length; i++) checksum += ((uint8_t *)sdt)[i];
+  return checksum == 0;
+}
+
+static root_sdp *verify_sdp(root_sdp *uv_rsdp) {
+  char *rsdp_char_ptr = (char *)uv_rsdp; 
   int i;
-  if(checksum) return 0;
-  if(rsdp->v1.version) {
-    printf("APCI revision > 2.\n");
-    checksum = 0;
-    printf("len : %i\n", rsdp->v2.len);
-    for(i = 0; i < rsdp->v2.len; i++) {
-      checksum += rsdp_csm_ptr[i];
+  uint8_t checksum = 0; 
+  if(uv_rsdp->revision) {
+    for(i = 0; i < uv_rsdp->len; i++) {
+      checksum += rsdp_char_ptr[i];
     }
   }
   else {
-    printf("APCI revision 1.\n");
     for(i = 0; i <= 20; i++) {
-      checksum += rsdp_csm_ptr[i];
+      checksum += rsdp_char_ptr[i];
     }
   }
-  if(checksum) {
-    return 0;
-    printf("Invalid, searching on.\n");
+  if(!checksum) {
+    printf("Found RSDP revision %i at address %x.\n", uv_rsdp->revision, uv_rsdp);
+    return uv_rsdp;
   }
-  printf("RSDP Verified!\n");
-  return 1;
+  printf("Skipped over invalid RSDP at 0x%p.\n", uv_rsdp);
+  return 0;
 }
 
-rsdp_t *find_RSDP() { 
+
+void find_root_sdp() {
   const char sig[9] = "RSD PTR ";
   uintptr_t *p = (void *)0x040e;
   uintptr_t *ebda_unshifted = (void *)p;
+  bool rsdt_verified;
 
-  void *ebda = (void *)((uintptr_t)ebda_unshifted << (uintptr_t)4 & (uintptr_t)0xfffff); 
+  void *ebda = PHYS_TO_VIRT((void *)((uintptr_t)ebda_unshifted << (uintptr_t)4 & (uintptr_t)0xfffff)); 
 
-  for(void *i = ebda; i <= ebda + 64000; i += 16) {
-    if(!(memcmp(sig, i, 8))) {
-      if(RSDP_verify(i)) {
-        return(i);
-      }
-    }
+
+
+  for(void *i = ebda; i <= ebda + 64000; i += 16) 
+    if(!(memcmp(sig, i, 8)) && ((rsdp = verify_sdp(i)))) break; 
+  
+
+  for(void *i = PHYS_TO_VIRT(0xe0000); i <= PHYS_TO_VIRT(0xfffff); i += 16)
+    if(!(memcmp(sig, i, 8)) && ((rsdp = verify_sdp(i)))) break; 
+  
+  if(!(rsdp)) {
+    printf("Couldn't find the RSDP... not sure what to do now.\n");
+    PANIC(KERNEL_PANIC_RSDP_UNFOUND);
+  }
+  
+  if(rsdp->revision) {
+    rsdt_verified = verify_sdt(PHYS_TO_VIRT(rsdp->xsdt));
+  } 
+  else {
+    rsdt_verified = verify_sdt(PHYS_TO_VIRT((uint64_t)rsdp->rsdt));
   }
 
-  for(void *i = (void *)0xe0000; i <= (void *)0xfffff; i += 16) {
-    if(!(memcmp(sig, i, 8))) {
-      if(RSDP_verify(i)) {
-        return(i);
-      }
-    }
+  if(!(rsdt_verified)) {
+    PANIC(KERNEL_PANIC_INVALID_RSDT);
   }
 }
-
-