shifted RSDP detection to limine, got high half direct mapping setup

Makefile

@@ -106,6 +106,7 @@ override HEADER_DEPS := $(addprefix obj/,$(CFILES:.c=.c.d) $(ASFILES:.S=.S.d))
 .PHONY: all
 all: bin/$(OUTPUT)
 	sh limine.sh
+	sh run.sh
 
 # Include header dependencies.
 -include $(HEADER_DEPS)

limine.sh

@@ -5,9 +5,9 @@ dd if=/dev/zero bs=1M count=0 seek=64 of=image.hdd
 sgdisk image.hdd -n 1:2048 -t 1:ef00 -m 1
 
 
-rm -rf limine
+#rm -rf limine
 # If first time: Download the latest Limine binary release for the 10.x branch.
-git clone https://codeberg.org/Limine/Limine.git limine --branch=v10.x-binary --depth=1
+#git clone https://codeberg.org/Limine/Limine.git limine --branch=v10.x-binary --depth=1
 
 # Build "limine" utility.
 make -C limine

obj/src/int.c.d

@@ -1,2 +1,3 @@
-obj/src/int.c.o: src/int.c src/common.h
+obj/src/int.c.o: src/int.c src/print.h src/common.h
+src/print.h:
 src/common.h:

obj/src/main.c.d

@@ -1,5 +1,6 @@
-obj/src/main.c.o: src/main.c src/../include/limine.h src/common.h \
+obj/src/main.c.o: src/main.c src/../include/limine.h src/acpi.h \
-  src/print.h
+  src/common.h src/print.h
 src/../include/limine.h:
+src/acpi.h:
 src/common.h:
 src/print.h:

run.sh

@@ -0,0 +1 @@
+qemu-system-x86_64 image.hdd

src/acpi.c

@@ -1,46 +1,26 @@
 #include "common.h"
+#include "print.h"
 
-// root system description pointer, points 
+#include "../include/limine.h"
-pstruct acpi_rsdp_header {
-  u8 signature[8];
-  u8 checksum;
-  u8 OEMID[6];
-  u8 revision;
-  u32 addr32_depr;
-  // v2
-  u32 len;
-  u64 addr;
-  u8 extended_checksum;
-  u8 resv[3];
-};
 
+// credit to dreamportdev's OSDev-Notes and the OSDev Wiki for table layouts
+
+#include "acpi.h"
 #define RSDT_SIGNATURE "RSDT"
 #define XSDT_SIGNATURE "XSDT"
 
-struct acpi_sdt_header {
+bool rsdp_validate(const u8* data) {
-  u8 signature[4];
+  if(memcmp(data, (const u8*)RSDP_SIGNATURE, 8) != 0) {
-  u32 len;
+    /* to debug in memcmp is broken somehow */
-  u8 revision;
+    if(data[0] == 'R' && data[1] == 'S' && data[2] == 'D' && data[3] == 'T' && data[4] == ' ') {
-  u8 checksum;
+      printn((const char*)data, 8);
-  u8 OEMID[6];
+    }
-  u8 OEM_table_id[8];
+    return false;
-  u32 OEM_revision;
+  }
-  u32 creator_id;
-  u32 creator_revision;
-};
 
-struct apci_rsdt {
+  struct acpi_rsdp_header* head = (struct acpi_rsdp_header*)data;
-  struct acpi_sdt_header header;
+  size_t len = sizeof(struct acpi_rsdp_header);
-  u32 addrs[];
+  len -= (head->revision == 2) * sizeof(u32) + sizeof(u64) + sizeof(u8) + sizeof(u8[3]);
-};
-
-struct xsdt {
-  struct acpi_rsdp_header header;
-  u64 addrs[];
-};
-
-
-bool rsdp_validate(u8* data, size_t len) {
   u32 sum_to_zero = 0;
   for(size_t i = 0; i < len; i++) {
     sum_to_zero += data[i];
@@ -49,4 +29,13 @@ bool rsdp_validate(u8* data, size_t len) {
   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

@@ -0,0 +1,46 @@
+#pragma once
+
+#include "common.h"
+
+
+#define RSDP_SIGNATURE "RSDT PTR "
+
+
+pstruct acpi_rsdp_header {
+  u8 signature[8];
+  u8 checksum;
+  u8 OEMID[6];
+  u8 revision;
+  u32 addr32_depr;
+  // v2
+  u32 len;
+  u64 addr;
+  u8 extended_checksum;
+  u8 resv[3];
+};
+
+struct acpi_sdt_header {
+  u8 signature[4];
+  u32 len;
+  u8 revision;
+  u8 checksum;
+  u8 OEMID[6];
+  u8 OEM_table_id[8];
+  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[];
+};
+
+extern struct acpi_rsdp_header* rsdp; 

src/common.h

@@ -15,3 +15,18 @@ typedef  int16_t  i16;
 typedef  int32_t  i32;
 typedef  int64_t  i64;
 
+static inline void INT(int n) {
+    asm volatile (
+        "int %0"
+        :
+        : "i"(n)
+    );
+}
+
+
+void* memcpy(void* restrict dst, const void* src, size_t n);
+void* memset(void* s, int c, size_t n);
+void* memmove(void* dst, const void* src, size_t n);
+int memcmp(const void* s1, const void* s2, size_t n);
+
+extern u64 hhdm_offset;

src/int.c

@@ -1,7 +1,14 @@
 #include <stdint.h>
 
+// for debugging
+#include "print.h"
+
 #include "common.h"
 
+
+// for trap debugging
+u64 dbg_var = 0;
+
 pstruct int_desc {
   u16 addr_low;
   u16 selector;
@@ -22,6 +29,8 @@ 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) {
@@ -29,7 +38,7 @@ void set_idt(u8 vect, void* handler, u8 dpl) {
   u64 addr = (u64) handler;
   ent->addr_low = addr & 0xFFFF;
   ent->addr_mid = (addr >> 16) & 0xFFFF;
-  ent->addr_mid = addr >> 32;
+  ent->addr_high = addr >> 32;
 
   ent->selector = CODE64_SELECTOR;
   ent->flags = ID_GATE_INT | dpl*ID_DPL | ID_PRESENT;
@@ -68,12 +77,16 @@ struct cpu_ctx {
 };
 
 struct cpu_ctx* interrupt_dispatch(struct cpu_ctx* ctx) {
-  draw(ctx->vect);
+  print("\n[IRQ ");
-
+  print8(ctx->vect);
+  print("] with message: ");
+  print64(dbg_var);
+  print("\n");
+  while(1);
   return ctx;
 }
 
-
+__attribute__((naked))
 void int_stub(void) {
   __asm__ volatile (
     "push %%rax\n"
@@ -108,7 +121,7 @@ void int_stub(void) {
     "pop %%rbx\n"
     "pop %%rax\n"
     "add $16, %%rsp\n"
-    "iret\n"
+    "iretq\n"
     :
     :
     : "memory"

src/main.c

@@ -2,8 +2,9 @@
 #include <stddef.h>
 #include <stdbool.h>
 
-
 #include "../include/limine.h"
+
+#include "acpi.h"
 #include "common.h"
 #include "print.h"
 
@@ -18,6 +19,27 @@ static volatile struct limine_framebuffer_request fb_req = {
   .revision = 0
 };
 
+
+__attribute__((used, section(".limine_requests")))
+static volatile struct limine_memmap_request mem_req = {
+  .id = LIMINE_MEMMAP_REQUEST_ID,
+  .revision = 0,
+};
+
+__attribute__((used, section(".limine_requests")))
+static volatile struct limine_hhdm_request hhdm_req = {
+  .id = LIMINE_HHDM_REQUEST_ID,
+  .revision = 0
+};
+
+__attribute__((used, section(".limine_requests")))
+static volatile struct limine_rsdp_request rsdp_req = {
+  .id = LIMINE_RSDP_REQUEST_ID,
+  .revision = 0
+};
+
+u64 hhdm_offset;
+
 __attribute__((used, section(".limine_requests_start")))
 static volatile u64 limine_requests_start_marker[] = LIMINE_REQUESTS_START_MARKER;
 
@@ -99,6 +121,53 @@ void draw(u8 vect) {
 
 extern void init_idt(void);
 
+extern u32 fg;
+extern u32 bg;
+void print_memmap_entry(struct limine_memmap_entry* entry) {
+  u32 savefg = fg;
+  u32 savebg = bg;
+  static const char* type_strs[] = {
+    "Usable",
+    "Reserved",
+    "ACPI Reclaimable",
+    "ACPI NVS",
+    "BAD!!!",
+    "Bootloader Reclaimable",
+    "Executable and Modules",
+    "Framebuffer",
+    "ACPI Tables",
+  };
+
+  static u32 type_colors[] = {
+    0x00AF00,
+    0xAF1F00,
+    0x7f7f00,
+    0x7f7f00,
+    0xFF0000,
+    0x007f7f,
+    0x408000,
+    0x0000FF,
+    0x00FF00
+  };
+
+  bg = type_colors[entry->type];
+  fg = ~bg;
+  
+  u64 addr = entry->base;
+  u64 end = addr + entry->length;
+  print("[");
+  print(type_strs[entry->type]);
+  print("]");
+  print64(addr);
+  print(" - ");
+  print64(end);
+  print("\n");
+  fg = savefg;
+  bg = savebg;
+}
+
+
+
 void kmain() {
   if(LIMINE_BASE_REVISION_SUPPORTED(limine_base_revision) == false) {
     hang();
@@ -110,11 +179,38 @@ void kmain() {
 
   fb = fb_req.response->framebuffers[0];
 
+  print_init(fb);
   init_idt();
 
-  print_init(fb);
+  if(!mem_req.response) {
+    print("Failed to get memory map :(\n)");
+    hang();
+  }
 
-  print("TEST THIS\nMessage for me please Mr Kernel");
+  if(!hhdm_req.response) {
+    print("Failed to get higher half direct mapping\n.");
+    hang();
+  }
+
+  hhdm_offset = hhdm_req.response->offset;
+
+  if(!rsdp_req.response) {
+    print ("Failed to find rsdp\n.");
+    hang();
+  }
+
+  rsdp = (struct acpi_rsdp_header*)(rsdp_req.response->address);
+
+  for(size_t i = 0; i < mem_req.response->entry_count; i++) {
+    print_memmap_entry(mem_req.response->entries[i]);
+  }
+
+  print("Found RSDP @ 0x");
+  print64((u64)rsdp);
+  put('\n');
+
+  print("With signature: ");
+  printn((char*)rsdp->signature, sizeof(rsdp->signature));
   
   hang();
   

src/print.c

@@ -4,7 +4,7 @@
 #include "../include/limine.h"
 
 u32 bg = 0x00000000;
-u32 fg = 0x00030200;
+u32 fg = (0x007F1754 << 1);
 static size_t row;
 static size_t col;
 static size_t term_width, term_height;
@@ -71,7 +71,7 @@ void put(int ch) {
     for (size_t x = 0; x < TERM_WIDTH; x++) {
       size_t off = (py + y) * fb_width + (px + x);
       bool padding = (y == 0 || y == TERM_HEIGHT-1 || x == 0 || x == TERM_WIDTH-1);
-      fb_scr[off] = ((~glyph & 1) | padding )? bg : (x^y * off + y*term_width) * fg;
+      fb_scr[off] = ((~glyph & 1) | padding )? bg : fg;
       glyph >>= !padding;
     }
   }
@@ -85,3 +85,31 @@ void print(const char* msg) {
     put(*(msg++));
   }
 }
+
+void printn(const char* msg, size_t len) {
+  while(len-->0) {
+    put(*(msg++));
+  }
+}
+
+static u8 digits[] = "0123456789ABCDEF";
+
+void print8(u8 n) {
+  put(digits[n>>4]);
+  put(digits[n&0xf]);
+}
+
+void print16(u16 n) {
+  print8(n >> 8);
+  print8(n & 0xFF);
+}
+
+void print32(u32 n) {
+  print16(n >> 16);
+  print16(n & 0xFFFF);
+}
+
+void print64(u64 n) {
+  print32(n >> 32);
+  print32(n & 0xFFFFFFFF);
+}

src/print.h

@@ -1,10 +1,16 @@
 #pragma once
 
 
+#include "common.h"
+
 struct limine_framebuffer;
 
 void put(int ch);
 
 void print(const char* msg);
-
+void printn(const char* msg, size_t len);
+void print64(u64 n);
+void print32(u32 n);
+void print16(u16 n);
+void print8(u8 n);
 void print_init(struct limine_framebuffer* fb);