topic Re: Is it possible to build the kernel for iMX6 hardware that does not have a PMIC? in i.MX Processors

Is it possible to build the kernel for iMX6 hardware that does not have a PMIC?

EdSutter — Tue, 28 Jan 2014 19:18:53 GMT

My custom iMX6 board does not have a PMIC (power manager) chip.

Actually it doesn't have much io, so I'm trying to turn off most of it in the kernel.

I edit .config to change this...

CONFIG_IMX_HAVE_PLATFORM_VIV_GPU=y

CONFIG_IMX_HAVE_PLATFORM_MXC_HDMI=y

CONFIG_IMX_HAVE_PLATFORM_IMX_ANATOP_THERMAL=y

CONFIG_IMX_HAVE_PLATFORM_FSL_OTG=y

CONFIG_IMX_HAVE_PLATFORM_FSL_USB_WAKEUP=y

CONFIG_IMX_HAVE_PLATFORM_IMX_PM=y

CONFIG_IMX_HAVE_PLATFORM_IMX_ASRC=y

CONFIG_IMX_HAVE_PLATFORM_IMX_MIPI_DSI=y

CONFIG_IMX_HAVE_PLATFORM_IMX_MIPI_CSI2=y

CONFIG_IMX_HAVE_PLATFORM_IMX_VDOA=y

CONFIG_IMX_HAVE_PLATFORM_IMX_PCIE=y

to this...

# CONFIG_IMX_HAVE_PLATFORM_VIV_GPU is not set

# CONFIG_IMX_HAVE_PLATFORM_MXC_HDMI is not set

# CONFIG_IMX_HAVE_PLATFORM_IMX_ANATOP_THERMAL is not set

# CONFIG_IMX_HAVE_PLATFORM_FSL_OTG is not set

# CONFIG_IMX_HAVE_PLATFORM_FSL_USB_WAKEUP is not set

# CONFIG_IMX_HAVE_PLATFORM_IMX_PM is not set

# CONFIG_IMX_HAVE_PLATFORM_IMX_ASRC is not set

# CONFIG_IMX_HAVE_PLATFORM_IMX_MIPI_DSI is not set

# CONFIG_IMX_HAVE_PLATFORM_IMX_MIPI_CSI2 is not set

# CONFIG_IMX_HAVE_PLATFORM_IMX_VDOA is not set

# CONFIG_IMX_HAVE_PLATFORM_IMX_PCIE is not set

but then 'make' seems to automatically re-enable these in the .config.

Is there a way to avoid this?

Re: Is it possible to build the kernel for iMX6 hardware that does not have a PMIC?

AnsonHuang — Sat, 08 Feb 2014 05:57:05 GMT

Hi, Ed

Seems like these setting are irrelated to external PMIC, as we have internal LDO in SOC, so I don't think you need to change these config if your board did NOT have external PMIC, actually, sabrelite board also do NOT have external PMIC, you can refer to its config file. For example, on our SabreSD board which has an external PMIC called PFuze, if we want to disable it, we can just remove the config of CONFIG_MFD_PFUZE.

Re: Is it possible to build the kernel for iMX6 hardware that does not have a PMIC?

EdSutter — Mon, 10 Feb 2014 15:25:29 GMT

Hi, thanks for responding. Just this past Friday I managed to get the board booted.

See this thread: Re: kernel boot problems with iMX6D running with 16bit DDR

The problem ended up to have nothing to do with PMIC (although my board does not have one); it was

caused by the fact that the kernel is configured by default to allocate .25G of RAM for contiguous memory.

My board currently only has .25G, so this obviously was failing and as a result; every driver that tried to

init and allocate some DMA memory from this pool failed.

Re: Is it possible to build the kernel for iMX6 hardware that does not have a PMIC?

YixingKong — Thu, 20 Feb 2014 06:37:50 GMT

Had your issue got resolved? If yes, we are going to close the discussion in 3 days. If you still need help please feel

free to contact Freescale.

Thanks,
Yixing

Re: Is it possible to build the kernel for iMX6 hardware that does not have a PMIC?

EdSutter — Thu, 20 Feb 2014 14:48:51 GMT

Yixing,

I'll just mark my above response as the correct answer...

The .25G allocation ended up being the primary problem.