Hi Felix, Both KCS and eSPI driver are ready x86 platforms. Please refer https://github.com/Intel-BMC/ Example: https://github.com/Intel-BMC/openbmc/blob/intel/meta-openbmc-mods/meta-ast2500/recipes-bsp/u-boot/files/0022-KCS-driver-support-in-uBoot.patch https://github.com/Intel-BMC/openbmc/blob/intel/meta-openbmc-mods/meta-ast2600/recipes-bsp/u-boot/files/0005-Ast2600-Enable-interrupt-in-u-boot.patch https://github.com/Intel-BMC/openbmc/blob/intel/meta-openbmc-mods/meta-common/recipes-kernel/linux/linux-aspeed/0022-Add-AST2500-eSPI-driver.patch BTW: you could set Acute travel logic to analyze eSPI bus. There is eSPI connector on Intel CRB platform. Thanks, Kwin. Dear James/andrew/Oskar Thanks a lot. I am studying eSPI spec. But it's hard to find any products with eSPI. Your reply gives more understanding about eSPI. Looking forward to more applications with eSPI in openbmc project. Thanks again. BR Felix | | zhang_cy1989 | | zhang_cy1989 at 163.com