On Mon, Sep 03, 2012 at 06:12:34PM +0200, Christian Gmeiner wrote:
2012/9/3 Kevin O'Connor kevin@koconnor.net:
On Sat, Sep 01, 2012 at 05:12:59PM +0200, Christian Gmeiner wrote:
With the current code the following happens:
VBE mode info request: 4101 VBE mode 4101 not found get_mode failed.
Looking at the provided mode (cx register) only bits 8-0 define the video mode number. I am not sure if the current code ever worked.
Signed-off-by: Christian Gmeiner christian.gmeiner@gmail.com
vgasrc/vbe.c | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-)
diff --git a/vgasrc/vbe.c b/vgasrc/vbe.c index 227a244..af72324 100644 --- a/vgasrc/vbe.c +++ b/vgasrc/vbe.c @@ -72,9 +72,24 @@ vbe_104f01(struct bregs *regs) struct vbe_mode_info *info = (void*)(regs->di+0); u16 mode = regs->cx;
- /*
* Bitfields for VESA/VBE video mode number:** Bit(s) Description (Table 04082)* 15 preserve display memory on mode change* 14 (VBE v2.0+) use linear (flat) frame buffer* 13 (VBE/AF 1.0P) VBE/AF initializes accelerator hardware* 12 reserved for VBE/AF* 11 (VBE v3.0) user user-specified CRTC refresh rate values* 10-9 reserved for future expansion* 8-0 video mode number (0xxh are non-VESA modes, 1xxh are VESA-defined)** see http://www.ctyme.com/intr/rb-0274.htm*/This is true for the call to set mode (vbe_104f02), but the spec does not say this for the get mode info call (104f01). It would be odd to pass in these additional bits when the caller just wants to get info on the given mode.
But if I want more information's about mode 0x101 with linear framebuffer support - thats the only way to get it. Also this is triggered by src/bootsplash.c so it seems to be a valid use-case.
Okay - looking at this closer. It looks to me that what bootsplash is doing is wrong. However, it also looks like real vgabios will ignore the bits. So, I propose changing both bootsplash and the vbe code.
Thanks.
-Kevin
From c8a3d3ee0194f0bb76e7ec8eeb59d7b986c24016 Mon Sep 17 00:00:00 2001
From: Kevin O'Connor kevin@koconnor.net Date: Mon, 3 Sep 2012 13:52:50 -0400 Subject: [PATCH 1/2] bootsplash: Don't pass mode flags to VBE get_mode_info call. To: seabios@seabios.org
The spec doesn't specify one can pass flags into the get_mode_info call, so don't do that.
Also, use the VBE_MODE_LINEAR_FRAME_BUFFER name where appropriate.
Signed-off-by: Kevin O'Connor kevin@koconnor.net --- src/bootsplash.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/src/bootsplash.c b/src/bootsplash.c index a85e2b2..78023a5 100644 --- a/src/bootsplash.c +++ b/src/bootsplash.c @@ -11,7 +11,8 @@ #include "util.h" // dprintf #include "jpeg.h" // splash #include "vbe.h" // struct vbe_info -#include "bmp.h" +#include "bmp.h" // bmp_alloc +
/**************************************************************** * Helper functions @@ -63,7 +64,7 @@ find_videomode(struct vbe_info *vesa_info, struct vbe_mode_info *mode_info struct bregs br; memset(&br, 0, sizeof(br)); br.ax = 0x4f01; - br.cx = (1 << 14) | videomode; + br.cx = videomode; br.di = FLATPTR_TO_OFFSET(mode_info); br.es = FLATPTR_TO_SEG(mode_info); call16_int10(&br); @@ -216,7 +217,7 @@ enable_bootsplash(void) dprintf(5, "Switching to graphics mode\n"); memset(&br, 0, sizeof(br)); br.ax = 0x4f02; - br.bx = (1 << 14) | videomode; + br.bx = videomode | VBE_MODE_LINEAR_FRAME_BUFFER; call16_int10(&br); if (br.ax != 0x4f) { dprintf(1, "set_mode failed.\n");