From: John Tsiombikas <nuclear@member.fsf.org>
Date: Sun, 18 Aug 2024 02:18:29 +0000 (+0300)
Subject: hacky video/serial console choice works
X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?a=commitdiff_plain;h=ec1e4d08130414c86e9a0693b956969b67c9552a;p=eightysix

hacky video/serial console choice works
---

diff --git a/kern/kern.ld b/kern/kern.ld
index c851a6d..fddd365 100644
--- a/kern/kern.ld
+++ b/kern/kern.ld
@@ -23,7 +23,6 @@ SECTIONS {
 	}
 	.bss ALIGN(4): {
 		_bss_start = .;
-		_bss_start_off = _bss_start - _kern_start;
 		* (.bss*);
 		* (COMMON);
 		. = ALIGN(4);
diff --git a/kern/src/boot.asm b/kern/src/boot.asm
index 25486e6..b8966d4 100644
--- a/kern/src/boot.asm
+++ b/kern/src/boot.asm
@@ -5,6 +5,7 @@
 
 extern _bootsect_start
 extern _kern_start_seg
+extern _kern_start
 extern _kern_size
 
 boot_driveno	equ 0500h
@@ -179,11 +180,11 @@ start:
 	jnz .rdloop
 
 	; loaded sucessfully, load segment registers and jump
-.done:	mov ax, _kern_start_seg
+.done:	xor ax, ax
 	mov ds, ax
 	mov es, ax
 	push ax
-	xor ax, ax
+	mov ax, _kern_start
 	push ax
 	retf
 
diff --git a/kern/src/con.c b/kern/src/con.c
index b9b91a4..b64cfb5 100644
--- a/kern/src/con.c
+++ b/kern/src/con.c
@@ -7,18 +7,24 @@
 
 static struct file *devfile;
 
+extern int in_panic;
+
 void con_init(void)
 {
+#if CONDEV != DEV_VID
 	if(!(devfile = dev_open(CONDEV, 0, O_RDWR))) {
 		panic("can't open console device %d,%d\n", CONDEV, 0);
 	}
+#endif
 }
 
 void con_putchar(int c)
 {
 	if(devfile) {
-		vid_putchar(c);	/* XXX dbg */
-		//devfile->dev->fop->write(devfile, &c, 1);
+		if(in_panic) {
+			vid_putchar(c);
+		}
+		devfile->dev->fop->write(devfile, &c, 1);
 	} else {
 		vid_putchar(c);
 	}
diff --git a/kern/src/config.h b/kern/src/config.h
index 45bf49f..d46832b 100644
--- a/kern/src/config.h
+++ b/kern/src/config.h
@@ -4,6 +4,6 @@
 #define VERSTR		"v0.0"
 
 /* CONDEV: which device to use for the kernel console (DEV_VID or DEV_SER) */
-#define CONDEV		DEV_SER
+#define CONDEV		DEV_VID
 
 #endif	/* CONFIG_H_ */
diff --git a/kern/src/dbg.c b/kern/src/dbg.c
index 5dcab9f..40d2fc5 100644
--- a/kern/src/dbg.c
+++ b/kern/src/dbg.c
@@ -3,6 +3,8 @@
 #include "dbg.h"
 #include "asmutil.h"
 
+int in_panic;
+
 __attribute__((noreturn))
 void panic(const char *fmt, ...)
 {
@@ -10,6 +12,8 @@ void panic(const char *fmt, ...)
 	struct wordregs regs;
 	struct segregs sregs;
 
+	in_panic = 1;
+
 	getregs(&regs);
 	regs.ip = getip();	/* replace ip with the caller's */
 	getsregs(&sregs);
@@ -27,3 +31,9 @@ void panic(const char *fmt, ...)
 
 	for(;;) halt();
 }
+
+void dbgping(int c)
+{
+	unsigned short __far *vmem = MK_FP(0xb800, 0);
+	vmem[79] = c | 0xc00;
+}
diff --git a/kern/src/dbg.h b/kern/src/dbg.h
index 55896dc..607ffc6 100644
--- a/kern/src/dbg.h
+++ b/kern/src/dbg.h
@@ -4,4 +4,8 @@
 __attribute__((noreturn))
 void panic(const char *fmt, ...);
 
+void dbgping(int c);
+
+#define dbgbreak()	asm volatile("int $3")
+
 #endif	/* DBG_H_ */
diff --git a/kern/src/dev.c b/kern/src/dev.c
index 312b821..9cc5aea 100644
--- a/kern/src/dev.c
+++ b/kern/src/dev.c
@@ -7,7 +7,7 @@ struct device devices[MAX_DEVICES];
 struct file *dev_open(int major, int minor, unsigned int flags)
 {
 	/* XXX temporary hack */
-	struct inode fakenode;
+	static struct inode fakenode;
 	static struct file file;
 
 	fakenode.dev_major = major;
@@ -16,12 +16,8 @@ struct file *dev_open(int major, int minor, unsigned int flags)
 	if(!devices[major].fop) {
 		return 0;
 	}
-	printf("dev_open(%x, %x, %x)\n", major, minor, flags);
 	if(devices[major].fop->open(&file, &fakenode, flags) < 0) {
-		panic("open failed");
 		return 0;
 	}
-	panic("WTF");
-
 	return &file;
 }
diff --git a/kern/src/ser.c b/kern/src/ser.c
index b30af46..e454e67 100644
--- a/kern/src/ser.c
+++ b/kern/src/ser.c
@@ -88,8 +88,6 @@ int ser_open(struct file *file, struct inode *inode, unsigned int flags)
 {
 	int port = inode->dev_minor;
 
-	panic("ser_open");
-
 	if(port < 0 || port >= 2) {
 		return -ENXIO;
 	}
@@ -126,7 +124,8 @@ static int ser_write(struct file *file, void *buf, int sz)
 {
 	int port = file->inode->dev_minor;
 	unsigned char *ptr = buf;
-	while(sz > 0) {
+
+	while(sz-- > 0) {
 		serput(port, *ptr++);
 	}
 	return ptr - (unsigned char*)buf;
diff --git a/kern/src/startup.asm b/kern/src/startup.asm
index 2cd9250..db24bae 100644
--- a/kern/src/startup.asm
+++ b/kern/src/startup.asm
@@ -7,7 +7,7 @@
 STACKSZ equ 4096
 
 extern kmain
-extern _bss_start_off
+extern _bss_start
 extern _bss_size
 
 global _start
@@ -18,13 +18,15 @@ _start:
 	xor ax, ax
 	mov sp, ax
 
+	mov ds, ax
+	mov es, ax
+	mov ss, ax
+
 	; zero .bss
-	mov di, _bss_start_off
+	mov di, _bss_start
 	mov cx, _bss_size
 	shr cx, 1
 	rep stosw
-	xor ax, ax
-	mov es, ax
 
 	call kmain