From c026350a842a02c225e3ecbcda5c298e70e37a62 Mon Sep 17 00:00:00 2001 From: BALATON Zoltan Date: Sun, 11 Aug 2019 23:14:53 +0200 Subject: [PATCH] ati-vga: Attempt to handle CRTC offset not exact multiple of stride 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 Message-id: 1c6fce457ef7e6f889e38dc0423791be92310a62.1565558093.git.balaton@eik.bme.hu Signed-off-by: Gerd Hoffmann --- hw/display/ati.c | 22 +++++++++++++++------- 1 file changed, 15 insertions(+), 7 deletions(-) diff --git a/hw/display/ati.c b/hw/display/ati.c index ff04f7eb4a..f24c23fa89 100644 --- a/hw/display/ati.c +++ b/hw/display/ati.c @@ -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 { -- 2.39.5