Accessing PicoZed 7030 eMMC in u-boot

Question

We are using PicoZed 7030 on a FMCv2 carrier board. Running a custom Linux from SD card, we can access both the SD card as well as the on-board eMMC (after explicitly enabling sdhci1 in the device tree). In u-boot, however, the only available mmc device is the SD card. What is necessary to also access eMMC in u-boot?

nitsch · Accepted Answer

We fixed it. It was an oversight on our part. Sorry for the noise.

When building the u-boot, make sure to use the picozed defconfig, not the zed defconfig. Duh.

The u-boot uses its own set of device tree files, apparently built into the u-boot image. Sources for these files are found in arch/arm/dts/. The one for zed only enables sdhci0 (the SD card) but not sdhci1 (the eMMC). This explains the behaviour we were observing. The dts for picozed only enables the latter by Default, which makes the eMMC work. Editing the dts to enable sdhci0 and sdhci1 makes it possible to access both SD card and eMMC in u-boot.