From acff86a794eecca3f48c15b1bd217434644b41a5 Mon Sep 17 00:00:00 2001
From: Jeremy Soller <jackpot51@gmail.com>
Date: Sat, 5 Feb 2022 20:57:53 -0700
Subject: [PATCH] Use 32-bit registers for thunking
---
src/disk.rs | 8 ++++----
src/lib.rs | 30 +++++++++++++++---------------
src/thunk.rs | 32 ++++++++++++++++----------------
x86/thunk.asm | 4 ++--
4 files changed, 37 insertions(+), 37 deletions(-)
diff --git a/src/disk.rs b/src/disk.rs
index ae88d39..e6dcac8 100644
--- a/src/disk.rs
+++ b/src/disk.rs
@@ -48,14 +48,14 @@ impl Disk for DiskBios {
ptr::write(DISK_ADDRESS_PACKET_ADDR as *mut DiskAddressPacket, dap);
let mut data = ThunkData::new();
- data.ax = 0x4200;
- data.dx = self.boot_disk as u16;
- data.si = DISK_ADDRESS_PACKET_ADDR as u16;
+ data.eax = 0x4200;
+ data.edx = self.boot_disk as u32;
+ data.esi = DISK_ADDRESS_PACKET_ADDR as u32;
data.with(self.thunk13);
//TODO: return result on error
- assert_eq!(data.ax, 0);
+ assert_eq!(data.eax, 0);
//TODO: check blocks transferred
dap = ptr::read(DISK_ADDRESS_PACKET_ADDR as *mut DiskAddressPacket);
diff --git a/src/lib.rs b/src/lib.rs
index ccec136..7bf287f 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -54,15 +54,15 @@ pub unsafe extern "C" fn kstart(
{
// Make sure we are in mode 3 (80x25 text mode)
let mut data = ThunkData::new();
- data.ax = 0x03;
+ data.eax = 0x03;
data.with(thunk10);
}
{
// Disable cursor
let mut data = ThunkData::new();
- data.ax = 0x0100;
- data.cx = 0x3F00;
+ data.eax = 0x0100;
+ data.ecx = 0x3F00;
data.with(thunk10);
}
@@ -123,10 +123,10 @@ pub unsafe extern "C" fn kstart(
{
// Get card info
let mut data = ThunkData::new();
- data.ax = 0x4F00;
- data.di = VBE_CARD_INFO_ADDR as u16;
+ data.eax = 0x4F00;
+ data.edi = VBE_CARD_INFO_ADDR as u32;
data.with(thunk10);
- if data.ax == 0x004F {
+ if data.eax == 0x004F {
let card_info = ptr::read(VBE_CARD_INFO_ADDR as *const VbeCardInfo);
let mut mode_ptr = card_info.videomodeptr as *const u16;
@@ -140,11 +140,11 @@ pub unsafe extern "C" fn kstart(
// Get mode info
let mut data = ThunkData::new();
- data.ax = 0x4F01;
- data.cx = mode;
- data.di = VBE_MODE_INFO_ADDR as u16;
+ data.eax = 0x4F01;
+ data.ecx = mode as u32;
+ data.edi = VBE_MODE_INFO_ADDR as u32;
data.with(thunk10);
- if data.ax == 0x004F {
+ if data.eax == 0x004F {
let mode_info = ptr::read(VBE_MODE_INFO_ADDR as *const VbeModeInfo);
// We only support 32-bits per pixel modes
@@ -176,11 +176,11 @@ pub unsafe extern "C" fn kstart(
format!("{:>4}x{:<4} {:>3}:{:<3}", w, h, aspect_w, aspect_h)
));
} else {
- error!("Failed to read VBE mode 0x{:04X} info: 0x{:04X}", mode, data.ax);
+ error!("Failed to read VBE mode 0x{:04X} info: 0x{:04X}", mode, data.eax);
}
}
} else {
- error!("Failed to read VBE card info: 0x{:04X}", data.ax);
+ error!("Failed to read VBE card info: 0x{:04X}", data.eax);
}
}
@@ -222,7 +222,7 @@ pub unsafe extern "C" fn kstart(
// Read keypress
let mut data = ThunkData::new();
data.with(thunk16);
- match (data.ax >> 8) as u8 {
+ match (data.eax >> 8) as u8 {
0x4B /* Left */ => {
if let Some(mut mode_i) = modes.iter().position(|x| x.0 == selected) {
if mode_i < rows {
@@ -277,8 +277,8 @@ pub unsafe extern "C" fn kstart(
},
0x1C /* Enter */ => {
let mut data = ThunkData::new();
- data.ax = 0x4F02;
- data.bx = selected;
+ data.eax = 0x4F02;
+ data.ebx = selected as u32;
data.with(thunk10);
},
_ => (),
diff --git a/src/thunk.rs b/src/thunk.rs
index 4b96fcf..658967a 100644
--- a/src/thunk.rs
+++ b/src/thunk.rs
@@ -5,27 +5,27 @@ use crate::THUNK_STACK_ADDR;
#[derive(Clone, Copy)]
#[repr(packed)]
pub struct ThunkData {
- pub di: u16,
- pub si: u16,
- pub bp: u16,
- sp: u16,
- pub bx: u16,
- pub dx: u16,
- pub cx: u16,
- pub ax: u16,
+ pub edi: u32,
+ pub esi: u32,
+ pub ebp: u32,
+ esp: u32,
+ pub ebx: u32,
+ pub edx: u32,
+ pub ecx: u32,
+ pub eax: u32,
}
impl ThunkData {
pub fn new() -> Self {
Self {
- di: 0,
- si: 0,
- bp: 0,
- sp: THUNK_STACK_ADDR as u16,
- bx: 0,
- dx: 0,
- cx: 0,
- ax: 0,
+ edi: 0,
+ esi: 0,
+ ebp: 0,
+ esp: THUNK_STACK_ADDR as u32,
+ ebx: 0,
+ edx: 0,
+ ecx: 0,
+ eax: 0,
}
}
diff --git a/x86/thunk.asm b/x86/thunk.asm
index 80e1b90..cb7662e 100644
--- a/x86/thunk.asm
+++ b/x86/thunk.asm
@@ -104,7 +104,7 @@ USE16
mov esp, 0x7C00 - 16
; load registers
- popa
+ popad
; enable interrupts
sti
@@ -116,7 +116,7 @@ USE16
cli
; save registers
- pusha
+ pushad
; restore cr0, will enable protected mode
mov eax, [.cr0]
--
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