Read stuff (e820)

kernel/kernel.c

@@ -20,12 +20,7 @@ void kernel_init() {
 	char* subtitle = "A x86 operating system, licenced under GPL-2.0";
 	println(subtitle, DEFAULT_COLOR);
 
-	char* e820_addr = (char*)0x9820;
-	uint e820_count = &e820_addr;
-	if ( e820_count <= 0 ) {
-		println(":(", DEFAULT_COLOR);
-	} else {
-		println(":D", DEFAULT_COLOR);
-	}
+	char* mem = (char*) get_phys_mem_size();
+	println(mem, DEFAULT_COLOR);
 
 }

kernel/memory.c

@@ -22,6 +22,12 @@
 
 static int bitmap = 0; 
 static uint last_block;
+
+uint get_phys_mem_size() {
+	uint e820_count = (uint) *BIOS_E820;
+	return e820_count;
+}
+
 void mod_bitmap(uint bit, uint bflag) {
 	// create a bitmask that will be applied to the bitmap
 	int bitmask = 1 << bit;
@@ -31,7 +37,6 @@ void mod_bitmap(uint bit, uint bflag) {
 	bitmap = (((bitmap & ~bitmask)) | (bflag << bit));
 }
 
-
 pointer block_alloc(uint blockidx) {
 	int block_bflag;
 	block_bflag = CHECK_BITMAP(bitmap, blockidx);

kernel/memory.h

@@ -1,5 +1,7 @@
 #include "../lib/types.h"
 
+#define BIOS_E820 (char*)0x9820
+
 #define BLOCK_SIZE 1024 // 1 KiB
 #define MAX_BLOCK_COUNT 32 // placeholder
 #define MEMSIZE_TO_BLOCKS(n) ((n*1024)/BLOCK_SIZE)
@@ -23,3 +25,5 @@ void pm_malloc_range(ulong start, ulong end, bool force); // allocate a range of
 
 pointer pm_malloc(uint block_count); // allocate some blocks
 void pm_free(int* p); // free a var (if allocated with pm_malloc)
+
+uint get_phys_mem_size(); // physical memory size with e820 left by the bootloader