https://bugzilla.kernel.org/show_bug.cgi?id=60523
--- Comment #26 from Alex Deucher <alexdeucher at gmail.com> --- In order to switch the mclk, the hw needs at least 450us. The vblank period of the 1600x1200 mode is 396us, so it's not long enough to switch. The switch has to happen during vblank to avoid seeing a flicker when the mclk changes. As such the driver picks a power state where the mclk doesn't change (the same power state that is used for multi-head). You could try specifying a 1600x1200 modeline with a longer vblank period if you want to use that mode and still support mclk switching. -- You are receiving this mail because: You are watching the assignee of the bug.
