Re: Fw: [Bugme-new] [Bug 6106] New: EGA problem since 2.6.14

Re: Fw: [Bugme-new] [Bug 6106] New: EGA problem since 2.6.14

[Samuel Thibault]

Hi,

Here is a fixup (vgacon-no-vertical-resize-on-ega):

EGA boards suck: they mostly have write-only registers. This is
particularly problematic for the overflow register: for being able to
write to it, we would have to handle vertical sync & such too, which
(I'd say) would potentially break a lot of configurations. Instead, just
disabling vertical resize for EGA boards is just nice enough (horizontal
resize still works).

Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>

--- drivers/video/console/vgacon.c.2.6.15.4	2006-02-22 01:35:49.000000000 +0100
+++ drivers/video/console/vgacon.c	2006-02-22 01:43:41.000000000 +0100
@@ -503,52 +503,56 @@ static int vgacon_doresize(struct vc_dat
 {
 	unsigned long flags;
 	unsigned int scanlines = height * c->vc_font.height;
-	u8 scanlines_lo, r7, vsync_end, mode, max_scan;
+	u8 scanlines_lo = 0, r7 = 0, vsync_end = 0, mode, max_scan;
 
 	spin_lock_irqsave(&vga_lock, flags);
 
-	outb_p(VGA_CRTC_MAX_SCAN, vga_video_port_reg);
-	max_scan = inb_p(vga_video_port_val);
-
-	if (max_scan & 0x80)
-		scanlines <<= 1;
-
-	outb_p(VGA_CRTC_MODE, vga_video_port_reg);
-	mode = inb_p(vga_video_port_val);
-
-	if (mode & 0x04)
-		scanlines >>= 1;
-
-	scanlines -= 1;
-	scanlines_lo = scanlines & 0xff;
-
-	outb_p(VGA_CRTC_OVERFLOW, vga_video_port_reg);
-	r7 = inb_p(vga_video_port_val) & ~0x42;
-
-	if (scanlines & 0x100)
-		r7 |= 0x02;
-	if (scanlines & 0x200)
-		r7 |= 0x40;
-
-	/* deprotect registers */
-	outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
-	vsync_end = inb_p(vga_video_port_val);
-	outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
-	outb_p(vsync_end & ~0x80, vga_video_port_val);
+	if (vga_video_type >= VIDEO_TYPE_VGAC) {
+		outb_p(VGA_CRTC_MAX_SCAN, vga_video_port_reg);
+		max_scan = inb_p(vga_video_port_val);
+
+		if (max_scan & 0x80)
+			scanlines <<= 1;
+
+		outb_p(VGA_CRTC_MODE, vga_video_port_reg);
+		mode = inb_p(vga_video_port_val);
+
+		if (mode & 0x04)
+			scanlines >>= 1;
+
+		scanlines -= 1;
+		scanlines_lo = scanlines & 0xff;
+
+		outb_p(VGA_CRTC_OVERFLOW, vga_video_port_reg);
+		r7 = inb_p(vga_video_port_val) & ~0x42;
+
+		if (scanlines & 0x100)
+			r7 |= 0x02;
+		if (scanlines & 0x200)
+			r7 |= 0x40;
+
+		/* deprotect registers */
+		outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
+		vsync_end = inb_p(vga_video_port_val);
+		outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
+		outb_p(vsync_end & ~0x80, vga_video_port_val);
+	}
 
 	outb_p(VGA_CRTC_H_DISP, vga_video_port_reg);
 	outb_p(width - 1, vga_video_port_val);
 	outb_p(VGA_CRTC_OFFSET, vga_video_port_reg);
 	outb_p(width >> 1, vga_video_port_val);
 
-	outb_p(VGA_CRTC_V_DISP_END, vga_video_port_reg);
-	outb_p(scanlines_lo, vga_video_port_val);
-	outb_p(VGA_CRTC_OVERFLOW, vga_video_port_reg);
-	outb_p(r7,vga_video_port_val);
-
-	/* reprotect registers */
-	outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
-	outb_p(vsync_end, vga_video_port_val);
+	if (vga_video_type >= VIDEO_TYPE_VGAC) {
+		outb_p(VGA_CRTC_V_DISP_END, vga_video_port_reg);
+		outb_p(scanlines_lo, vga_video_port_val);
+		outb_p(VGA_CRTC_OVERFLOW, vga_video_port_reg);
+		outb_p(r7,vga_video_port_val);
+
+		/* reprotect registers */
+		outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
+		outb_p(vsync_end, vga_video_port_val);
+	}
 
 	spin_unlock_irqrestore(&vga_lock, flags);
 

Re: Fw: [Bugme-new] [Bug 6106] New: EGA problem since 2.6.14

[Andrew Morton]

Samuel Thibault <samuel.thibault@ens-lyon.org> wrote:
>
> Here is a fixup (vgacon-no-vertical-resize-on-ega):

Thanks.  I'm 51% inclined to hold this off for 2.6.17 - vgacon seems to be
a bit accident-prone lately.

Your patch was against some prehistoric kernel which didn't have the
vgacon_xres and vgacon_yres initialisations in vgacon_doresize().

Please confirm that this is correct:




From: Samuel Thibault <samuel.thibault@ens-lyon.org>

EGA boards suck: they mostly have write-only registers.  This is
particularly problematic for the overflow register: for being able to write
to it, we would have to handle vertical sync & such too, which (I'd say)
would potentially break a lot of configurations.  Instead, just disabling
vertical resize for EGA boards is just nice enough (horizontal resize still
works).

Fixes http://bugzilla.kernel.org/show_bug.cgi?id=6106

Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Cc: Rafal Olearski <olearski@mail2.kim.net.pl>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---

 drivers/video/console/vgacon.c |   79 ++++++++++++++++---------------
 1 files changed, 41 insertions(+), 38 deletions(-)

diff -puN drivers/video/console/vgacon.c~vgacon-no-vertical-resizing-on-ega drivers/video/console/vgacon.c
--- devel/drivers/video/console/vgacon.c~vgacon-no-vertical-resizing-on-ega	2006-02-21 17:49:40.000000000 -0800
+++ devel-akpm/drivers/video/console/vgacon.c	2006-02-21 17:52:27.000000000 -0800
@@ -509,57 +509,60 @@ static int vgacon_doresize(struct vc_dat
 {
 	unsigned long flags;
 	unsigned int scanlines = height * c->vc_font.height;
-	u8 scanlines_lo, r7, vsync_end, mode, max_scan;
+	u8 scanlines_lo = 0, r7 = 0, vsync_end = 0, mode, max_scan;
 
 	spin_lock_irqsave(&vga_lock, flags);
 
-	outb_p(VGA_CRTC_MAX_SCAN, vga_video_port_reg);
-	max_scan = inb_p(vga_video_port_val);
-
-	if (max_scan & 0x80)
-		scanlines <<= 1;
-
 	vgacon_xres = width * VGA_FONTWIDTH;
 	vgacon_yres = height * c->vc_font.height;
-	outb_p(VGA_CRTC_MODE, vga_video_port_reg);
-	mode = inb_p(vga_video_port_val);
-
-	if (mode & 0x04)
-		scanlines >>= 1;
-
-	scanlines -= 1;
-	scanlines_lo = scanlines & 0xff;
-
-	outb_p(VGA_CRTC_OVERFLOW, vga_video_port_reg);
-	r7 = inb_p(vga_video_port_val) & ~0x42;
-
-	if (scanlines & 0x100)
-		r7 |= 0x02;
-	if (scanlines & 0x200)
-		r7 |= 0x40;
-
-	/* deprotect registers */
-	outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
-	vsync_end = inb_p(vga_video_port_val);
-	outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
-	outb_p(vsync_end & ~0x80, vga_video_port_val);
+	if (vga_video_type >= VIDEO_TYPE_VGAC) {
+		outb_p(VGA_CRTC_MAX_SCAN, vga_video_port_reg);
+		max_scan = inb_p(vga_video_port_val);
+
+		if (max_scan & 0x80)
+			scanlines <<= 1;
+
+		outb_p(VGA_CRTC_MODE, vga_video_port_reg);
+		mode = inb_p(vga_video_port_val);
+
+		if (mode & 0x04)
+			scanlines >>= 1;
+
+		scanlines -= 1;
+		scanlines_lo = scanlines & 0xff;
+
+		outb_p(VGA_CRTC_OVERFLOW, vga_video_port_reg);
+		r7 = inb_p(vga_video_port_val) & ~0x42;
+
+		if (scanlines & 0x100)
+			r7 |= 0x02;
+		if (scanlines & 0x200)
+			r7 |= 0x40;
+
+		/* deprotect registers */
+		outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
+		vsync_end = inb_p(vga_video_port_val);
+		outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
+		outb_p(vsync_end & ~0x80, vga_video_port_val);
+	}
 
 	outb_p(VGA_CRTC_H_DISP, vga_video_port_reg);
 	outb_p(width - 1, vga_video_port_val);
 	outb_p(VGA_CRTC_OFFSET, vga_video_port_reg);
 	outb_p(width >> 1, vga_video_port_val);
 
-	outb_p(VGA_CRTC_V_DISP_END, vga_video_port_reg);
-	outb_p(scanlines_lo, vga_video_port_val);
-	outb_p(VGA_CRTC_OVERFLOW, vga_video_port_reg);
-	outb_p(r7,vga_video_port_val);
-
-	/* reprotect registers */
-	outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
-	outb_p(vsync_end, vga_video_port_val);
+	if (vga_video_type >= VIDEO_TYPE_VGAC) {
+		outb_p(VGA_CRTC_V_DISP_END, vga_video_port_reg);
+		outb_p(scanlines_lo, vga_video_port_val);
+		outb_p(VGA_CRTC_OVERFLOW, vga_video_port_reg);
+		outb_p(r7,vga_video_port_val);
+
+		/* reprotect registers */
+		outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
+		outb_p(vsync_end, vga_video_port_val);
+	}
 
 	spin_unlock_irqrestore(&vga_lock, flags);
-
 	return 0;
 }
 
_

Re: Fw: [Bugme-new] [Bug 6106] New: EGA problem since 2.6.14

[Samuel Thibault]

Hi,

Andrew Morton, le Tue 21 Feb 2006 17:57:10 -0800, a écrit :
> Your patch was against some prehistoric kernel which didn't have the
> vgacon_xres and vgacon_yres initialisations in vgacon_doresize().

Ah, yes, sorry.

> Please confirm that this is correct:

This is indeed.

Regards,
Samuel

Re: Fw: [Bugme-new] [Bug 6106] New: EGA problem since 2.6.14

[Samuel Thibault]

Hi,

Here is another fixup for EGA cursor resize function.

This corrects cursor resize on ega boards: registers are write-only, so
we shouldn't even try to read them. And on ega, 31/30 produces a flat
cursor. Using 31/31 is better: except with 32 pixels high fonts, it
shouldn't show up.

Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>

--- drivers/video/console/vgacon.c.git	2006-02-24 10:43:25.000000000 +0100
+++ drivers/video/console/vgacon.c	2006-02-25 01:17:17.000000000 +0100
@@ -433,17 +433,22 @@ static void vgacon_set_cursor_size(int x
 	cursor_size_lastto = to;
 
 	spin_lock_irqsave(&vga_lock, flags);
-	outb_p(0x0a, vga_video_port_reg);	/* Cursor start */
-	curs = inb_p(vga_video_port_val);
-	outb_p(0x0b, vga_video_port_reg);	/* Cursor end */
-	cure = inb_p(vga_video_port_val);
+	if (vga_video_type >= VIDEO_TYPE_VGAC) {
+		outb_p(VGA_CRTC_CURSOR_START, vga_video_port_reg);
+		curs = inb_p(vga_video_port_val);
+		outb_p(VGA_CRTC_CURSOR_END, vga_video_port_reg);
+		cure = inb_p(vga_video_port_val);
+	} else {
+		curs = 0;
+		cure = 0;
+	}
 
 	curs = (curs & 0xc0) | from;
 	cure = (cure & 0xe0) | to;
 
-	outb_p(0x0a, vga_video_port_reg);	/* Cursor start */
+	outb_p(VGA_CRTC_CURSOR_START, vga_video_port_reg);
 	outb_p(curs, vga_video_port_val);
-	outb_p(0x0b, vga_video_port_reg);	/* Cursor end */
+	outb_p(VGA_CRTC_CURSOR_END, vga_video_port_reg);
 	outb_p(cure, vga_video_port_val);
 	spin_unlock_irqrestore(&vga_lock, flags);
 }
@@ -455,7 +460,10 @@ static void vgacon_cursor(struct vc_data
 	switch (mode) {
 	case CM_ERASE:
 		write_vga(14, (c->vc_pos - vga_vram_base) / 2);
-		vgacon_set_cursor_size(c->vc_x, 31, 30);
+	        if (vga_video_type >= VIDEO_TYPE_VGAC)
+			vgacon_set_cursor_size(c->vc_x, 31, 30);
+		else
+			vgacon_set_cursor_size(c->vc_x, 31, 31);
 		break;
 
 	case CM_MOVE:
@@ -493,7 +501,10 @@ static void vgacon_cursor(struct vc_data
 						10 ? 1 : 2));
 			break;
 		case CUR_NONE:
-			vgacon_set_cursor_size(c->vc_x, 31, 30);
+			if (vga_video_type >= VIDEO_TYPE_VGAC)
+				vgacon_set_cursor_size(c->vc_x, 31, 30);
+			else
+				vgacon_set_cursor_size(c->vc_x, 31, 31);
 			break;
 		default:
 			vgacon_set_cursor_size(c->vc_x, 1,