Messages in this thread Patch in this message | | | Date | Wed, 22 Feb 2006 02:41:02 +0100 | From | Samuel Thibault <> | Subject | Re: Fw: [Bugme-new] [Bug 6106] New: EGA problem since 2.6.14 |
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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); - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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