Hi
I am using yocto to create SD card boot images for a custom imx6dl ( duallite ) board with hardware design identical to the Freescale SabreSDP reference board other than addition of a USB hub and removal of few peripherals such as camera and accelerometer. The Gigabit Ethernet circuit is identical to the Freescale reference board and uses RGMII.
I want to configure and compile the Linux kernel so that the PTP system (IEEE1588 Packet Timing Protocol) is not enabled for Ethernet - specifically I want to use the NVCC GPIO_16 for other purposes. On the 3.10.17-1.0.0 kernel, the GPIO_16 outputs a 50 MHz clock. The kernel config menu ( obtained by running "bitbake -c menuconfig linux-imx") automatically forces the PTP feature on if FEC Ethernet is enabled! There is no way to have just the Ethernet enabled for RGMII with clock supplied from the PHY on ENET_REF_CLK pin and not use the GPIO_16 pin. I believe that GPIO_16 is required only for RMII and not RGMII unless PTP feature is required.
Does anybody have a solution/ patch to achieve this?
I used the following to setup the kernel and SD card image compile:
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repo init -u git://git.freescale.com/imx/fsl-arm-yocto-bsp.git -b imx-3.10.17-1.0.0_ga
repo sync
MACHINE=imx6dlsabresd source fsl-setup-release.sh -b build_sabresd_dl_min -e x11
bitbake core-image-base
The report had the lines:
Your build environemnt has been configured with:
MACHINE=imx6dlsabresd
SDKMACHINE=i686
DISTRO=poky
EULA=1
--------------------------
Thanks in advance.
I would recommend leaving the GPIO_16 pin unused as in the SABRE board, if possible. This because of the internal muxing on this pin, as it’s connected to the ENET_CLK pad.
The RGMII implementation does require a 125MHz Reference Clock not necessarily on the GPIO_16 pin, but since it’s related to the ENET_CLK it’s possible that it could cause interference.