HDMI 1080p with OMAP4460 custom board : Android ICS

sanjay c

Hello,

I am working on a custom board based on OMAP4460, running Android ICS. HDMI resolution when android boots is 1280x720. When i try to play a video with 1080p resolution, i get the following errors

omapdss DISPC error: timeout waiting for EVSYNC

[ 497.464630] mgr_blank while GO is set

[ 497.491271] omapdss HDMI: Enter hdmi_display_disable

[ 497.598907] omapdss DISPC error: timeout waiting for EVSYNC

[ 497.605133] omapdss HDMI: Release c-state constraint for HDMI

The pixel clock required for the lcd is 23.5 Mhz.

DSS_FCLK = 118.153 Mhz.

lck_div = 1

pck_div = 5 [ 118.153/5 = 23.63 Mhz]

My understanding is pixel_clock required for 1080p is 148.5 Mhz. Since the DSS_FCLK(118 Mhz) is less than 148.5 Mhz i am getting the above error.

Is my understanding correct ?

Can i play 1080p videos with DSS_FCLK = 118 Mhz ?

Any pointers would be helpful.

Thank you for your time.

Regards,

Sanjay

over 12 years ago

0 Venkat Ramana Peddigari over 12 years ago

TI__Expert 4120 points

Hi Sanjay,

Yes, your understanding is correct. If the DSS_FCLK is less than 148.5 MHz then you cannot play or render 1080p content on the HDMI. The solution is to change the clock source to PRCM CLK in the board file for your custom board so that it would get a clock source with greater than 148.5 MHz.

Please try this change and let us know if that helps.

Thanks & Best Regards,

Venkat

0 sanjay c over 12 years ago in reply to Venkat Ramana Peddigari

Intellectual 290 points

Hi Venkat,

Thank you for your reply.

I was able to scale the dss_fclk using an option in menuconfig CONFIG_OMAP2_DSS_MIN_FCK_PER_PCK.

Regards,

Sanjay.C

0 Venkat Ramana Peddigari over 12 years ago in reply to sanjay c

TI__Expert 4120 points

Hi Sanjay,

Are you able to play the 1080p videos using the PRCM clock? You should also ensure that the 1080p timings are picked by the HDMI TV?

Thanks & Best Regards,

Venkat

0 sanjay c over 12 years ago in reply to Venkat Ramana Peddigari

Intellectual 290 points

Hi Venkat,

Yes you are right, the resolution when android boots is 720p and not 1080p even though the TV supports 1080p.

Are you referring to this clock when you say PRCM clock,

.clocks = {
.dispc = {
.dispc_fclk_src = OMAP_DSS_CLK_SRC_FCK,
},

Please clarify,

Regards,

Sanjay

0 Venkat Ramana Peddigari over 12 years ago in reply to sanjay c

TI__Expert 4120 points

Hi Sanjay,

Yes, I am referring to OMAP_DSS_CLK_SRC_FCK as PRCM CLK source.

The hardware composer has the logic embedded to pick the best timing for HDMI that matches closely with LCD panel resolution. You have to force it to pick the 1080p timing by appropriate changes in the hardware composer code.

Thanks & Best Regards,

Venkat

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HDMI 1080p with OMAP4460 custom board : Android ICS