[coreboot] Micron e.MMC Memory(MTFC64GAPALBH-IT) is not detected

[Murali Ayyappan]

Hi,

Our custom board is designed based on Denverton SOC.

The used boot loader is coreboot-4.13 version and Linux kernel 5.10.30 version.

In our design, the eMMC interface is used, and connected Micron e.MMC memory(MTFC64GAPALBH-IT) to it.

The eMMC is enabled in coreboot device tree file.

Here's the snippet from ./src/mainboard/intel/harcuvar/devicetree.cb file.

device pci 1a.2 on end # UART 2
        device pci 1c.0 on end # eMMC
        device pci 1f.0 on end # LPC bridge
        device pci 1f.2 on end # PMC/ACPI

and, in linux kernel following kernel modules are enabled for host controller,

# MMC/SD/SDIO Host Controller Drivers
#
# CONFIG_MMC_DEBUG is not set
CONFIG_MMC_SDHCI=y
CONFIG_MMC_SDHCI_IO_ACCESSORS=y
CONFIG_MMC_SDHCI_PCI=y
CONFIG_MMC_RICOH_MMC=y
CONFIG_MMC_SDHCI_ACPI=y
# CONFIG_MMC_SDHCI_PLTFM is not set
# CONFIG_MMC_WBSD is not set
# CONFIG_MMC_TIFM_SD is not set
# CONFIG_MMC_SPI is not set
# CONFIG_MMC_CB710 is not set
# CONFIG_MMC_VIA_SDMMC is not set
# CONFIG_MMC_VUB300 is not set
# CONFIG_MMC_USHC is not set
# CONFIG_MMC_USDHI6ROL0 is not set
CONFIG_MMC_CQHCI=y

and for memory device enabled following kernel modules,
CONFIG_MMC=y
CONFIG_PWRSEQ_EMMC=y
CONFIG_PWRSEQ_SIMPLE=y
CONFIG_MMC_BLOCK=y
CONFIG_MMC_BLOCK_MINORS=8

Per SOC datasheet the host controller is seen in Bus 0, Device 28 and Function 0 in PCI bus, but the connected memory is not detected under this controller.

when added debug prints in linux kernel driver source files, found that the mmc_rescan( ) function is failing due to mmc_attach failing with errno -110.

Thanks,

Murali