Re: [RFC 00/13] arm64: allwinner: Add A64 DE2 pipeline support

[Jernej Åkrabec]

Hi,

Dne Äetrtek, 26. april 2018 ob 15:26:49 CEST je Jagan Teki napisal(a):
> On Wed, Apr 25, 2018 at 11:29 PM, Jernej Åkrabec
> 
> <jernej.skrabec@xxxxxxxx> wrote:
> > Hi,
> > 
> > Dne sreda, 25. april 2018 ob 12:34:09 CEST je Jagan Teki napisal(a):
> >> On Tue, Apr 24, 2018 at 9:02 PM, Jernej Åkrabec <jernej.skrabec@xxxxxxxx>
> > 
> > wrote:
> >> > Hi,
> >> > 
> >> > Dne torek, 24. april 2018 ob 15:34:12 CEST je Jagan Teki napisal(a):
> >> >> Allwinner A64 has display engine pipeline like other Allwinner SOC's
> >> >> A83T/H3/H5.
> >> >> 
> >> >> A64 DE2 behaviour similar to Allwinner A83T where mixer0, connected to
> >> >> tcon0 with RGB, LVDS MIPI-DSI and mixer1, connected to tcon1 with
> >> >> HDMI.
> >> >> This series merely concentrated on HDMI pipeline and rest will add
> >> >> eventually.
> >> >> 
> >> >> patch 1: dt-bindings for a64 DE2 CCU
> >> >> 
> >> >> patch 2: a64 DE2 CCU node addition
> >> >> 
> >> >> patch 3: dt-bindings for a64 DE2 pipeline
> >> >> 
> >> >> patch 4 - 5: dt-bindings for a64 mixer0 and tcon-lcd
> >> >> 
> >> >> patch 6: a64 DE2 pipeline node addition
> >> >> 
> >> >> patch 7 - 8: dt-bindings for a64 HDMI and HDMI PHY
> >> >> 
> >> >> patch 9: a64 HDMI nodes addition
> >> >> 
> >> >> patch 10 - 11: dt-bindings for a64 mixer1 and tcon-tv
> >> >> 
> >> >> patch 12: a64 HDMI pipeline
> >> >> 
> >> >> patch 13: enable HDMI out on bananpi-m64
> >> >> 
> >> >> Tested HDMI on bananapi-m64 (along with DE2 SRAM C changes from [1]
> >> >> thread), able to detect the HDMI but, no penguins on screen.
> >> >> 
> >> >> Request for any suggestions.
> >> > 
> >> > You are mising sunxi-ng clock patches. PLL_VIDEO0 and PLL_VIDEO1 need
> >> > fixes by setting minimum stable frequency. Please note that datasheet
> >> > may
> >> > have wrong information. That was obvious in H3 case and I had to check
> >> > minimum stable PLL_VIDEO frequency in BSP driver.
> >> 
> >> Can you point me the clock patches?
> > 
> > Here is my A64 HDMI wip repo, which includes my clock changes:
> > https://github.com/jernejsk/linux-1/tree/a64_hdmi_wip
> > 
> > At some point HDMI output worked ok, I'm not sure in what state I left the
> > code.
> 
> Jernej, thanks for the regulator change in another mail, yes
> bananapi-m64 has HVCC regulator for HDMI glue, with this I'm able to
> see penguins on screen.

Ok, great.

> 
> >> I've phadled only CLK_PLL_VIDEO0
> >> on hdmi_phy So we need CLK_PLL_VIDEO1 as fourth clock?
> > 
> > I'm not sure what is the best way. I guess some research is needed. There
> > is even the possibility that one bit (SUN8I_HDMI_PHY_PLL_CFG1_CKIN_SEL)
> > in hdmi phy needs to be toggled depending on which clock is selected as
> > HDMI source. I never finished my research since I'm waiting to SRAM C
> > claiming patches.
> > 
> > At the end, HDMI driver should be tested by both, PLL_VIDEO0 and
> > PLL_VIDEO1 as a HDMI clock source, otherwise there is no guarantee that
> > we got binding right. A83T, H3 and H5 has only one possible HDMI parent
> > clock, so it was much easier in this regard.
> 
> From Figure 3-3.Module Clock Diagram of
> Allwinner_A64_User_Manual_V1.1.pdf clearly shows PLL_VIDEO1 is
> connected TCON1 which intern used by HDMI. I've verified both
> PLL_VIDEO0 and 1 both seems working. I'm thinking we can go for
> PLL_VIDEO1 as per datasheet, any suggestions?
> 
> Jagan.

Actually, same diagram also shows that PLL_VIDEO0 can be connected to TCON1/
HDMI. Since DT descibes HW, probably both phandles should be specified and 
driver should decide some way which one to select. Additionally, HDMI 
controller and HDMI PHY should use same PLL at the same time. If nothing is 
done, PLL_VIDEO0 will always be used, which might interfere in dual monitor 
setup.

Best regards,
Jernej