Hi, On Fri, Jul 29, 2022 at 08:12:07PM +0200, Mateusz Kwiatkowski wrote: > I'm just noting that the modelines you defined in drm_modes.c are different > to the ones you're removing here. > > The horizontal sync differences probably doesn't matter too much, VC4 uses > those only as a hint anyway and generates sync autonomously, so the slight > differences will only cause the image to slightly shift horizontally. > > But you're also changing the 480i vertical sync (vsync_start is now 488 > instead of 487, etc.). Are you sure that this won't break anything? This > will probably shift the image by 1 line (which for the 480i might actually > mean going out of spec), and I _think_ it might control the odd vs. even > field first modes on some drivers. I won't be able to test this before > Monday, but I'm just pointing out the potential issue. I didn't see any difference on both vc4 and sun4i, but you might be right about this. I didn't have much confidence in the vc4 modes since they were broken before your patches, but maybe I should have used yours still. > BTW, I've seen a similar thing in the sun4i driver changes (patch 32/35) and > the differences in vertical sync are even more dramatic. It's entirely > possible that the current timings in sun4i are broken and the new ones are > correct (the new ones certainly look saner to me), but I'd double-check if > that driver does not have any quirks that would _require_ such weird > settings. The only thing sun4i requires from the new mode is the line number anyway, which stays the same. Maxime
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