mirrors/qemu
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

ati-vga: Attempt to handle CRTC offset not exact multiple of stride

Browse Source 
MacOS uses non-0 offset so it needs this and the resulting
vbe_start_addr seems correct but picture is still broken with OpenBIOS
after FCode runs but that maybe due to firmware problems now. After
boot, picture is now correct.

It also occured to me that these CRTC regs are also present in VGA so
I wonder if they should be shared in case some drivers try to poke
them via VGA regs or these are a separate set of regs for extended
mode. Added a comment noting this but drivers I've tried so far
program the card accessing ati regs so I did not attempt to change it.

Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
Message-id: 1c6fce457ef7e6f889e38dc0423791be92310a62.1565558093.git.balaton@eik.bme.hu
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This commit is contained in:
BALATON Zoltan 2019-08-11 23:14:53 +02:00 committed by Gerd Hoffmann
parent 747d7ad231
commit c026350a84
1 changed files with 15 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

22
hw/display/ati.c
View File

@ -50,6 +50,7 @@ static void ati_vga_switch_mode(ATIVGAState *s)
s->mode = EXT_MODE;
if (s->regs.crtc_gen_cntl & CRTC2_EN) {
/* CRT controller enabled, use CRTC values */
/* FIXME Should these be the same as VGA CRTC regs? */
uint32_t offs = s->regs.crtc_offset & 0x07ffffff;
int stride = (s->regs.crtc_pitch & 0x7ff) * 8;
int bpp = 0;
@ -101,16 +102,23 @@ static void ati_vga_switch_mode(ATIVGAState *s)
(s->regs.dac_cntl & DAC_8BIT_EN ? VBE_DISPI_8BIT_DAC : 0));
/* now set offset and stride after enable as that resets these */
if (stride) {
int bypp = DIV_ROUND_UP(bpp, BITS_PER_BYTE);
vbe_ioport_write_index(&s->vga, 0, VBE_DISPI_INDEX_VIRT_WIDTH);
vbe_ioport_write_data(&s->vga, 0, stride);
if (offs % stride == 0) {
vbe_ioport_write_index(&s->vga, 0, VBE_DISPI_INDEX_Y_OFFSET);
vbe_ioport_write_data(&s->vga, 0, offs / stride);
} else {
/* FIXME what to do with this? */
error_report("VGA offset is not multiple of pitch, "
"expect bad picture");
stride *= bypp;
if (offs % stride) {
DPRINTF("CRTC offset is not multiple of pitch\n");
vbe_ioport_write_index(&s->vga, 0,
VBE_DISPI_INDEX_X_OFFSET);
vbe_ioport_write_data(&s->vga, 0, offs % stride / bypp);
}
vbe_ioport_write_index(&s->vga, 0, VBE_DISPI_INDEX_Y_OFFSET);
vbe_ioport_write_data(&s->vga, 0, offs / stride);
DPRINTF("VBE offset (%d,%d), vbe_start_addr=%x\n",
s->vga.vbe_regs[VBE_DISPI_INDEX_X_OFFSET],
s->vga.vbe_regs[VBE_DISPI_INDEX_Y_OFFSET],
s->vga.vbe_start_addr);
}
}
} else {