Hi, On 11/10/20 9:43 PM, Ben Widawsky wrote: > --- > drivers/Kconfig | 1 + > drivers/Makefile | 1 + > drivers/cxl/Kconfig | 30 +++++++++++ > drivers/cxl/Makefile | 5 ++ > drivers/cxl/acpi.c | 119 ++++++++++++++++++++++++++++++++++++++++++ > drivers/cxl/acpi.h | 15 ++++++ > include/acpi/actbl1.h | 52 ++++++++++++++++++ > 7 files changed, 223 insertions(+) > diff --git a/drivers/cxl/Kconfig b/drivers/cxl/Kconfig > new file mode 100644 > index 000000000000..dd724bd364df > --- /dev/null > +++ b/drivers/cxl/Kconfig > @@ -0,0 +1,30 @@ > +# SPDX-License-Identifier: GPL-2.0-only > +menuconfig CXL_BUS > + tristate "CXL (Compute Express Link) Devices Support" > + help > + CXL is a bus that is electrically compatible with PCI-E, but layers > + three protocols on that signalling (CXL.io, CXL.cache, and CXL.mem). The > + CXL.cache protocol allows devices to hold cachelines locally, the > + CXL.mem protocol allows devices to be fully coherent memory targets, the > + CXL.io protocol is equivalent to PCI-E. Say 'y' to enable support for > + the configuration and management of devices supporting these protocols. > + > +if CXL_BUS > + > +config CXL_BUS_PROVIDER > + tristate > + > +config CXL_ACPI > + tristate "CXL Platform Support" > + depends on ACPI > + default CXL_BUS Please provide some justification for something other than the default default of 'n'. We try hard not to add drivers/modules that are not required for bootup. > + select CXL_BUS_PROVIDER > + help > + CXL Platform Support is a prerequisite for any CXL device driver that > + wants to claim ownership of the component register space. By default > + platform firmware assumes Linux is unaware of CXL capabilities and > + requires explicit opt-in. This platform component also mediates > + resources described by the CEDT (CXL Early Discovery Table) end sentence with '.' > + > + Say 'y' to enable CXL (Compute Express Link) drivers. or 'm' > +endif -- ~Randy