[PATCH] ARM: imx: propagate DI clock changes up the clock tree to PLL5
l.stach at pengutronix.de
Fri Apr 11 07:00:12 PDT 2014
Am Donnerstag, den 10.04.2014, 21:48 -0700 schrieb Tim Harvey:
> On Thu, Apr 10, 2014 at 9:31 PM, Tim Harvey <tharvey at gateworks.com> wrote:
> > On Wed, Apr 9, 2014 at 8:39 AM, Russell King
> > <rmk+kernel at arm.linux.org.uk> wrote:
> >> Allows clk_set_rate() on the DI clocks to propagate up to PLL5.
> >> This allows imx-drm to produce the exact clock rate required with no
> >> modulation due to the fractional divider. Modulation of the clock rate
> >> can and does prevent TVs from locking to the HDMI signal - they will
> >> report no signal rather than trying to lock to such a signal.
> >> Signed-off-by: Russell King <rmk+kernel at arm.linux.org.uk>
> >> ---
> >> I still have this patch which is required so that imx-drm is capable of
> >> producing HDMI clocks which are close enough to the HDMI defined
> >> frequencies such that TVs and similar can recognise the signal. Without
> >> this, I don't get any kind of output on my TV desite imx-drm being set
> >> to the correct mode. I have proven that this is because the HDMI clock
> >> is *very* wrong without this patch.
> >> arch/arm/mach-imx/clk-imx6q.c | 12 ++++++------
> >> 1 file changed, 6 insertions(+), 6 deletions(-)
> > Hi Russell,
> > This fixed HDMI on the boards I'm testing it on (Gateworks Ventana).
> > Without it I encounter the same issue you describe above.
> > Tested-by: Tim Harvey <tharvey at gateworks.com>
> > Tim
> I neglected to mention that even after this patch I do see an issue
> where the monitor does not sync if plugged in on board powerup. The
> following is what I see with DEBUG enabled in imx-hdmi:
I think this is fallout from how we handle the EDID fetch on startup. We
have patches lying around to fix this. Will post them in a minute.
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