firmware: arm_sdei: Add driver for Software Delegated Exceptions

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 firmware notifications (such as
firmware-first RAS) or promote an IRQ that has been promoted to a
firmware-assisted NMI.

Add the code for detecting the SDEI version and the framework for
registering and unregistering events. Subsequent patches will add the
arch-specific backend code and the necessary power management hooks.

Only shared events are supported, power management, private events and
discovery for ACPI systems will be added by later patches.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/MAINTAINERS b/MAINTAINERS
index 82ad0eabce4f..c06885c4c0f1 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -12618,6 +12618,15 @@ L:	linux-media@vger.kernel.org
 S:      Supported
 F:      drivers/media/pci/solo6x10/
 
+SOFTWARE DELEGATED EXCEPTION INTERFACE (SDEI)
+M:      James Morse <james.morse@arm.com>
+L:      linux-arm-kernel@lists.infradead.org
+S:      Maintained
+F:      Documentation/devicetree/bindings/arm/firmware/sdei.txt
+F:      drivers/firmware/arm_sdei.c
+F:      include/linux/sdei.h
+F:      include/uapi/linux/sdei.h
+
 SOFTWARE RAID (Multiple Disks) SUPPORT
 M:      Shaohua Li <shli@kernel.org>
 L:      linux-raid@vger.kernel.org