Re: [Qemu-devel] [PATCH v5 2/2] ati-vga: Implement DDC and EDID info from monitor

[Gerd Hoffmann]

On Thu, Jun 20, 2019 at 12:55:23PM +0200, BALATON Zoltan wrote:
> This adds DDC support to ati-vga and connects i2c-ddc to it. This
> allows at least MacOS with an ATI ndrv, Linux radeonfb and MorphOS to

linux radeonfb is rv100 only, and aty128fb has no i2c support.
Do MacOS and MorphOS have working edid with both card variants?

> +    case GPIO_MONID ... GPIO_MONID + 3:
> +        /* FIXME What does Radeon have here? */
> +        if (s->dev_id == PCI_DEVICE_ID_ATI_RAGE128_PF) {
> +            /* Rage128p accesses DDC used to get EDID on these pins */
> +            ati_reg_write_offs(&s->regs.gpio_monid,
> +                               addr - GPIO_MONID, data, size);
> +            if ((s->regs.gpio_monid & BIT(25)) &&

Extra enable bit, ok.

> +                addr <= GPIO_MONID + 2 && addr + size > GPIO_MONID + 2) {

Hmm, isn't this just "addr == GPIO_MONID + 2" ?

> +                s->regs.gpio_monid = ati_i2c(s->bbi2c, s->regs.gpio_monid, 
> 1);

So all i2c bits are shifted by one compared to rv100, correct?

cheers,
  Gerd