From: John Tsiombikas <nuclear@member.fsf.org>
Date: Tue, 3 Oct 2023 20:59:09 +0000 (+0300)
Subject: clear bss and move on
X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?a=commitdiff_plain;h=deedd497760693c4810008f247d1fc5ce16455dd;p=com32

clear bss and move on
---

diff --git a/com32.ld b/com32.ld
index b83e861..701a0b4 100644
--- a/com32.ld
+++ b/com32.ld
@@ -25,7 +25,6 @@ SECTIONS {
 		* (COMMON);
 		. = ALIGN(4);
 		_bss_end = .;
-		_bss_size = _bss_end - _bss_start;
 	}
 
 	. = ALIGN(4);
diff --git a/src/intr.c b/src/intr.c
index 6feb03d..29ca70e 100644
--- a/src/intr.c
+++ b/src/intr.c
@@ -90,6 +90,11 @@ void init_intr(void)
 		interrupt(i, 0);
 	}
 
+	/* mask all IRQs by default */
+	for(i=0; i<16; i++) {
+		mask_irq(i);
+	}
+
 	/* by including intrtab.h here the series of INTR_ENTRY_* macros will be
 	 * expanded to a series of function prototypes for all interrupt entry
 	 * points and the corresponding calls to set_intr_entry to set up the IDT
diff --git a/src/keyb.c b/src/keyb.c
index b6e31f3..2b01408 100644
--- a/src/keyb.c
+++ b/src/keyb.c
@@ -57,6 +57,7 @@ void kb_init(void)
 
 	interrupt(IRQ_TO_INTR(KB_IRQ), kbintr);
 	kb_intr_enable();
+	unmask_irq(KB_IRQ);
 }
 
 void kb_intr_enable(void)
diff --git a/src/loader.asm b/src/loader.asm
index 4cdb702..ea0de70 100644
--- a/src/loader.asm
+++ b/src/loader.asm
@@ -238,6 +238,13 @@ detect_memory:
 	mov esi, str_fail
 	call printstr
 
+	mov esi, memdet_cmos_msg
+	call printstr
+	call detect_mem_cmos
+	jnc .done
+	mov esi, str_fail
+	call printstr
+
 	mov si, memdet_fail_msg
 	call printstr
 	jmp exit
@@ -249,9 +256,10 @@ detect_memory:
 str_ok db 'OK',10,0
 str_fail db 'failed',10,0
 memdet_fail_msg db 'Failed to detect available memory!',10,0
-memdet_e820_msg db "Detecting RAM (BIOS 15h/0xe820)... ",0
-memdet_e801_msg db "Detecting RAM (BIOS 15h/0xe801)... ",0
-memdet_88_msg	db "Detecting RAM (BIOS 15h/0x88, max 64mb)... ",0
+memdet_e820_msg db 'Detecting RAM (BIOS 15h/0xe820)... ',0
+memdet_e801_msg db 'Detecting RAM (BIOS 15h/0xe801)... ',0
+memdet_88_msg	db 'Detecting RAM (BIOS 15h/0x88, max 64mb)... ',0
+memdet_cmos_msg db 'Detecting RAM (CMOS)...',0
 
 	; detect extended memory using BIOS call 15h/e820
 detect_mem_e820:
@@ -387,6 +395,32 @@ detect_mem_88:
 .fail:	stc
 	ret
 
+detect_mem_cmos:
+	mov al, 31h
+	out 70h, al
+	in al, 71h
+	mov ah, al
+	mov al, 30h
+	out 70h, al
+	in al, 71h
+
+	test ax, ax
+	jz .fail
+
+	; ax has size in KB, convert to bytes in eax
+	and eax, 0xffff
+	shl eax, 10
+
+	mov esi, mem_map
+	mov dword [si], 100000h
+	mov [si + 4], eax
+	mov dword [mem_map_size], 1
+	clc
+	ret
+.fail:	stc
+	ret
+
+
 	align 4
 mem_map_size dd 0
 mem_map times 128 db 0
diff --git a/src/psaux.c b/src/psaux.c
index 4f1e2b0..a0fb58d 100644
--- a/src/psaux.c
+++ b/src/psaux.c
@@ -35,6 +35,7 @@ static int intr_mode;
 void init_psaux(void)
 {
 	interrupt(IRQ_TO_INTR(12), psaux_intr);
+	unmask_irq(12);
 
 	init_mouse();
 	set_mouse_bounds(0, 0, 319, 199);
diff --git a/src/startup.asm b/src/startup.asm
index 21e25e9..8c7dfbb 100644
--- a/src/startup.asm
+++ b/src/startup.asm
@@ -4,16 +4,25 @@
 %include 'macros.inc'
 
 	extern main
+	extern _bss_start
+	extern _bss_end
 
 	global startup
 startup:
-	mov ebx, 0xb8000 + 156
-	mov byte [ebx], '@'
-	mov byte [ebx + 2], '@'
-	mov byte [ebx + 160], '@'
-	mov byte [ebx + 162], '@'
+	; clear .bss
+	mov eax, _bss_end
+	sub eax, _bss_start
+	test eax, eax
+	jz .nobss
+	mov ecx, eax
+	mov edi, _bss_start
+	xor eax, eax
+	shr ecx, 2
+	rep stosd
+.nobss:
 
 	call main
+	cli	; XXX
 
 .waitkey:
 	in al, 64h
diff --git a/src/timer.c b/src/timer.c
index da313f9..f4a812b 100644
--- a/src/timer.c
+++ b/src/timer.c
@@ -86,6 +86,7 @@ void init_timer(void)
 
 	/* set the timer interrupt handler */
 	interrupt(IRQ_TO_INTR(0), timer_handler);
+	unmask_irq(0);
 }
 
 void set_alarm(unsigned long msec, void (*func)(void))