atimach64gx: Fix fb_pitch calculation.

Also, move the calculation to crtc_update where we calculate everything else (including bits per pixel which is needed for the fb_pitch calculation.
This commit is contained in:
joevt 2024-02-28 16:08:32 -08:00 committed by dingusdev
parent fe21108f08
commit c42e1f28d6
1 changed files with 14 additions and 2 deletions

View File

@ -378,8 +378,7 @@ void AtiMach64Gx::write_reg(uint32_t reg_offset, uint32_t value, uint32_t size)
break;
case ATI_CRTC_OFF_PITCH:
new_value = value;
this->fb_pitch = extract_bits<uint32_t>(new_value, ATI_CRTC_PITCH, ATI_CRTC_PITCH_size) * 8;
this->fb_ptr = &this->vram_ptr[extract_bits<uint32_t>(new_value, ATI_CRTC_OFFSET, ATI_CRTC_OFFSET_size) * 8];
this->crtc_update();
return;
case ATI_CRTC_INT_CNTL:
{
@ -609,6 +608,19 @@ void AtiMach64Gx::crtc_update()
need_recalc = true;
}
static uint8_t bits_per_pixel[8] = {0, 0, 4, 8, 16, 24, 32, 0};
int new_fb_pitch = extract_bits<uint32_t>(this->regs[ATI_CRTC_OFF_PITCH], ATI_CRTC_PITCH, ATI_CRTC_PITCH_size) * bits_per_pixel[this->pixel_format];
if (new_fb_pitch != this->fb_pitch) {
this->fb_pitch = new_fb_pitch;
need_recalc = true;
}
uint8_t* new_fb_ptr = &this->vram_ptr[extract_bits<uint32_t>(this->regs[ATI_CRTC_OFF_PITCH], ATI_CRTC_OFFSET, ATI_CRTC_OFFSET_size) * 8];
if (new_fb_ptr != this->fb_ptr) {
this->fb_ptr = new_fb_ptr;
need_recalc = true;
}
// pixel clock = source_freq / post_div
int m = 8 >> (this->dac_regs[Rgb514::F0_M0] >> 6);
int vco_div = (this->dac_regs[Rgb514::F0_M0] & 0x3F) + 65;