From 6411dc0c9c7bb7662f30e0d7919784b405db1535 Mon Sep 17 00:00:00 2001
From: Ain <41307858+nero@users.noreply.github.com>
Date: Tue, 24 Sep 2019 08:16:22 +0000
Subject: [PATCH] Turn CHS fields in drive table into words

CHS arithmetic will be done on 32-bit integers, the operand for division
of DX:AX is a word, so we save a conversion step.

Additionally, i might reuse these fields for pointing to a SYS driver later.
---
 kernel/drive.asm | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/kernel/drive.asm b/kernel/drive.asm
index 243b8e0..31efa81 100644
--- a/kernel/drive.asm
+++ b/kernel/drive.asm
@@ -1,11 +1,15 @@
 ; drive table
-%define drivetab_type    0x00 ; BYTE 0=unassigned, 1=BIOS/CHS, 2=BIOS/LBA
-%define drivetab_num     0x01 ; BYTE DL number
-%define drivetab_heads   0x02 ; CHS heads
-%define drivetab_spt     0x03 ; CHS sectors per track
-%define drivetab_sectors 0x04 ; total number of sectors
-%define drivetab_offset  0x08 ; partition offset
-%define drivetab_size    0x0C
+%define drivetab_type    0x00 ; BYTE  0=unassigned, 1=BIOS/CHS, 2=BIOS/LBA
+%define drivetab_num     0x01 ; BYTE  DL number
+
+; CHS data for type=1
+; Might be reused for driver address
+%define drivetab_heads   0x02 ; WORD  CHS heads
+%define drivetab_spt     0x04 ; WORD  CHS sectors per track
+
+%define drivetab_sectors 0x06 ; DWORD total number of sectors
+%define drivetab_offset  0x0A ; DWORD partition offset
+%define drivetab_size    0x0E
 
 drive_table:
   dw 0