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+* Software Delegated Exception Interface (SDEI)
+
+Firmware implementing the SDEI functions described in ARM document number
+ARM DEN 0054A ("Software Delegated Exception Interface") can be used by
+Linux to receive notification of events such as those generated by
+firmware-first error handling, or from an IRQ that has been promoted to
+a firmware-assisted NMI.
+
+The interface provides a number of API functions for registering callbacks
+and enabling/disabling events. Functions are invoked by trapping to the
+privilege level of the SDEI firmware (specified as part of the binding
+below) and passing arguments in a manner specified by the "SMC Calling
+Convention (ARM DEN 0028B):
+
+ r0 => 32-bit Function ID / return value
+ {r1 - r3} => Parameters
+
+Note that the immediate field of the trapping instruction must be set
+to #0.
+
+The SDEI_EVENT_REGISTER function registers a callback in the kernel
+text to handle the specified event number.
+
+The sdei node should be a child node of '/firmware' and have required
+properties:
+
+ - compatible : should contain:
+ * "arm,sdei-1.0" : For implementations complying to SDEI version 1.x.
+
+ - method : The method of calling the SDEI firmware. Permitted
+ values are:
+ * "smc" : SMC #0, with the register assignments specified in this
+ binding.
+ * "hvc" : HVC #0, with the register assignments specified in this
+ binding.
+Example:
+ firmware {
+ sdei {
+ compatible = "arm,sdei-1.0";
+ method = "smc";
+ };
+ };