Using booting drive instead of ata detection

2 files changed, 4 insertions, 68 deletions

diff --git a/boot/entry.asm b/boot/entry.asm
index 8f12dff..dc65b97 100644
--- a/boot/entry.asm
+++ b/boot/entry.asm
@@ -454,6 +454,9 @@ protected_mode:
 	mov ax, (gdt_tss - gdt) | 0b11 ; Load TSS in ring 3
 	ltr ax
 
+	mov eax, drive ; Pass drive to kernel loader
+	push eax ; Push as third kernel parameter
+
 	mov eax, vid_info ; Pass VBE struct to kernel loader
 	push eax ; Push as second kernel parameter
 
diff --git a/boot/load.c b/boot/load.c
index 12102a2..dfa6e9c 100644
--- a/boot/load.c
+++ b/boot/load.c
@@ -508,55 +508,6 @@ static void print(const char *data)
  * IDE/ATA
  */
 
-static u8 *ide_buf = NULL;
-
-static void ide_select_drive(u8 bus, u8 drive)
-{
-	if (bus == ATA_PRIMARY) {
-		if (drive == ATA_MASTER)
-			outb(ATA_PRIMARY_IO + ATA_REG_HDDEVSEL, 0xa0);
-		else
-			outb(ATA_PRIMARY_IO + ATA_REG_HDDEVSEL, 0xb0);
-	} else {
-		if (drive == ATA_MASTER)
-			outb(ATA_SECONDARY_IO + ATA_REG_HDDEVSEL, 0xa0);
-		else
-			outb(ATA_SECONDARY_IO + ATA_REG_HDDEVSEL, 0xb0);
-	}
-}
-
-static u8 ide_find(u8 bus, u8 drive)
-{
-	u16 io = bus == ATA_PRIMARY ? ATA_PRIMARY_IO : ATA_SECONDARY_IO;
-	ide_select_drive(bus, drive);
-
-	// Reset
-	outb(io + ATA_REG_SECCOUNT0, 0);
-	outb(io + ATA_REG_LBA0, 0);
-	outb(io + ATA_REG_LBA1, 0);
-	outb(io + ATA_REG_LBA2, 0);
-
-	// Identify
-	outb(io + ATA_REG_COMMAND, ATA_CMD_IDENTIFY);
-	u8 status = inb(io + ATA_REG_STATUS);
-	if (!status)
-		return 0;
-
-	while ((inb(io + ATA_REG_STATUS) & ATA_SR_BSY) != 0)
-		;
-
-	do {
-		status = inb(io + ATA_REG_STATUS);
-		if (status & ATA_SR_ERR)
-			return 0;
-	} while ((status & ATA_SR_DRQ) == 0);
-
-	for (int i = 0; i < BLOCK_COUNT; i++)
-		*(u16 *)(ide_buf + i * 2) = inw(io + ATA_REG_DATA);
-
-	return 1;
-}
-
 static void ide_delay(u16 io) // 400ns
 {
 	for (int i = 0; i < 4; i++)
@@ -611,23 +562,6 @@ static u32 ata_read(void *buf, u32 lba, u32 sector_count, u8 drive)
 	return sector_count;
 }
 
-static u8 ata_probe(void)
-{
-	for (u8 i = 0; i < 4; i++) {
-		u32 bus = i < 2 ? ATA_PRIMARY : ATA_SECONDARY;
-		u32 drive = i % 2 ? ATA_MASTER : ATA_SLAVE;
-
-		if (!ide_find(bus, drive))
-			continue;
-
-		u8 found_drive = (bus << 1) | drive;
-		// TODO: What about the other drives?
-		return found_drive;
-	}
-
-	return 0;
-}
-
 /**
  * EXT2
  */
@@ -885,12 +819,11 @@ static s32 elf_load(const char *path, u8 drive)
  * Let's go!
  */
 
-int main(void *first, void *second)
+int main(void *first, void *second, u8 drive)
 {
 	serial_install();
 	print("Loaded bootloader!\n");
 
-	u8 drive = ata_probe();
 	assert(drive);
 
 	s32 elf = elf_load("/apps/kernel/exec", drive);