ARM System Control and Management Interface (SCMI) protocol is a set of operating system-independent software interfaces that are used in system management. SCMI is extensible and currently provides interfaces for: Discovery and self-description of the interfaces it supports, Power domain management which is the ability to place a given device or domain into the various power-saving states that it supports, Performance management which is the ability to control the performance of a domain that is composed of compute engines such as application processors and other accelerators, Clock management which is the ability to set and inquire rates on platform managed clocks and Sensor management which is the ability to read sensor data, and be notified of sensor value. This protocol library provides interface for all the client drivers making use of the features offered by the SCMI.
This enables support for the SCMI power domains which can be enabled or disabled via the SCP firmware This driver can also be built as a module. If so, the module will be called scmi_pm_domain. Note this may needed early in boot before rootfs may be available.
System Control and Power Interface (SCPI) Message Protocol is defined for the purpose of communication between the Application Cores(AP) and the System Control Processor(SCP). The MHU peripheral provides a mechanism for inter-processor communication between SCP and AP. SCP controls most of the power management on the Application Processors. It offers control and management of: the core/cluster power states, various power domain DVFS including the core/cluster, certain system clocks configuration, thermal sensors and many others. This protocol library provides interface for all the client drivers making use of the features offered by the SCP.
This enables support for the SCPI power domains which can be enabled or disabled via the SCP firmware
The Software Delegated Exception Interface (SDEI) is an ARM standard for registering callbacks from the platform firmware into the OS. This is typically used to implement RAS notifications.
Say Y or M here if you want to enable BIOS Enhanced Disk Drive Services real mode BIOS calls to determine which disk BIOS tries boot from. This information is then exported via sysfs. This option is experimental and is known to fail to boot on some obscure configurations. Most disk controller BIOS vendors do not yet implement this feature.
Say Y if you want EDD disabled by default, even though it is compiled into the
kernel. Say N if you want EDD enabled by default. EDD can be dynamically set
using the kernel parameter 'edd={on|skipmbr|off}'.
Add the firmware-provided (unmodified) memory map to /sys/firmware/memmap. That memory map is used for example by kexec to set up parameter area for the next kernel, but can also be used for debugging purposes. See also Documentation/ABI/testing/sysfs-firmware-memmap.
If your firmware supplies the PCDP table, and you want to automatically use the primary console device it describes as the Linux console, say Y here. If your firmware supplies the HCDP table, and you want to use the first serial port it describes as the Linux console, say Y here. If your EFI ConOut path contains only a UART device, it will become the console automatically. Otherwise, you must specify the "console=hcdp" kernel boot argument. Neither the PCDP nor the HCDP affects naming of serial devices, so a serial console may be /dev/ttyS0, /dev/ttyS1, etc, depending on how the driver discovers devices. You must also enable the appropriate drivers (serial, VGA, etc.) See DIG64_HCDPv20_042804.pdf available from <http://www.dig64.org/specifications/>
Say Y here if you want to query SMBIOS/DMI system identification information from userspace through /sys/class/dmi/id/ or if you want DMI-based module auto-loading.
Say Y or M here to enable the exporting of the raw DMI table data via sysfs. This is useful for consuming the data without requiring any access to /dev/mem at all. Tables are found under /sys/firmware/dmi when this option is enabled and loaded.
This option enables the kernel to find the region of memory in which the ISCSI Boot Firmware Table (iBFT) resides. This is necessary for iSCSI Boot Firmware Table Attributes module to work properly.
This option enables support for detection and exposing of iSCSI Boot Firmware Table (iBFT) via sysfs to userspace. If you wish to detect iSCSI boot parameters dynamically during system boot, say Y. Otherwise, say N.
This option enables support for communicating with the firmware on the Raspberry Pi.
Say Y or M here to enable the exporting of the QEMU firmware configuration (fw_cfg) file entries via sysfs. Entries are found under /sys/firmware/fw_cfg when this option is enabled and loaded.
Allow the qemu_fw_cfg device to be initialized via the kernel command line or using a module parameter. WARNING: Using incorrect parameters (base address in particular) may crash your system.
Intel Stratix10 service layer runs at privileged exception level, interfaces with the service providers (FPGA manager is one of them) and manages secure monitor call to communicate with secure monitor software at secure monitor exception level. Say Y here if you want Stratix10 service layer support.
The Intel Remote System Update (RSU) driver exposes interfaces access through the Intel Service Layer to user space via sysfs device attribute nodes. The RSU interfaces report/control some of the optional RSU features of the Stratix 10 SoC FPGA. The RSU provides a way for customers to update the boot configuration of a Stratix 10 SoC device with significantly reduced risk of corrupting the bitstream storage and bricking the system. Enable RSU support if you are using an Intel SoC FPGA with the RSU feature enabled and you want Linux user space control. Say Y here if you want Intel RSU support.
A device with "download mode" enabled will upon an unexpected warm-restart enter a special debug mode that allows the user to "download" memory content over USB for offline postmortem analysis. The feature can be enabled/disabled on the kernel command line. Say Y here to enable "download mode" by default.
TI System Control Interface (TISCI) Message Protocol is used to manage compute systems such as ARM, DSP etc with the system controller in complex System on Chip(SoC) such as those found on certain keystone generation SoC from TI. System controller provides various facilities including power management function support. This protocol library is used by client drivers to use the features provided by the system controller.
Some devices (including most early Tegra-based consumer devices on the market) are booted with the Trusted Foundations secure monitor active, requiring some core operations to be performed by the secure monitor instead of the kernel. This option allows the kernel to invoke the secure monitor whenever required on devices using Trusted Foundations. See the functions and comments in linux/firmware/trusted_foundations.h or the device tree bindings for "tlm,trusted-foundations" for details on how to use it. Choose N if you don't know what this is about.
This driver communicates with the firmware on the Cortex-M3 secure processor of the Turris Mox router. Enable if you are building for Turris Mox, and you will be able to read the device serial number and other manufacturing data and also utilize the Entropy Bit Generator for hardware random number generation.