MCIMX6Q4AVT10AD HDMI not working

[mikhailburkov]

Hi all,

HDMI not working on my custom board based on MCIMX6Q4AVT10AD.

Register reading:

HDMI_DESIGN_ID:0x00120000 =  0x00

HDMI_REVISION_ID:0x00120001 =  0x00

HDMI_PRODUCT_ID0:0x00120002 = 0x00

MCIMX6Q4AVT10AD not have VPU. Does not HDMI also?!

The identical assembly of LINUX works fine on the board with the MCIMX6Q5EYM10AC processor.

Questions:

1) If the CPU does not have a VPU, then there is no HDMI?

2) If the MCIMX6Q4AVT10AD has HDMI, why is HDMI_DESIGN_ID read as 0?

3) Is there any difference in the turning on of HDMI for processors with and without VPU?

Thanks.

Best regards,

Mikhail Burkov

[fabio_estevam · Accepted solution]

Hi Mikhail,

Please see this patch for the mainline kernel:

https://patchwork.kernel.org/patch/9874831/ 

Does it work for you?

Regards,

Fabio Estevam

[mikhailburkov]

Hi Fabio!

Thank you very much for your help.

VIDEO_27M_CLK_ROOT, needed for HDMI, in default LINUX assembly routed through VPU. If VPU not present, then HDMI block not have a clock. In this case we must a enable MIPI clock:

/* Turn on MIPI core cfg clock */

reg = readl(&mxc_ccm->CCGR3);
reg |= MXC_CCM_CCGR3_MIPI_CORE_CFG_MASK;
writel(reg, &mxc_ccm->CCGR3);

HDMI on MCIMX6Q4AVT10AD works fine!

Best regards,

Mikhail Burkov

[mikhailburkov]

Hi Fabio,

Thank you, very useful information.

We will check it in the coming days.

[joanxie]

vpu is for coding video, hdmi is for display, no vpu doesn't mean no hdmi.

if you want to know if your chip support hdmi  or not, pls "fuse read 0 4 1"

one can read 32 bits fuse map from bank 0 work 4, the bit 7 is for HDMI, if it is 1, then the chip has no HDMI.

[mikhailburkov]

Joan Xie, thanks for your answer.

I read the register 0x021BC440 (Value of OTP Bank0 Word4 OCOTP_CFG3):

MCIMX6Q5EYM10AD: [0x021BC440] = 0x00620302. HDMI works normally on this processor.

MCIMX6Q4AVT10AD: [0x021BC440] = 0x00628302. HDMI not working!

How so?! The NXP site (BasicType ) speaks about the presence of HDMI from the MCIMX6Q4AVT10AD processor! In datasheet and reference manual there is also no data about the absence of HDMI!

[mikhailburkov]

The contents of the registers [0x021BC440] differ only in bit 15.

Bit 7 for both processors is 0.

That is, both processors have HDMI?

Why then can not enable HDMI on the processor MCIMX6Q4AVT10AD?