GIC: Add APIs to query interrupt types

These APIs allow the GIC implementation to categorize interrupt numbers
into SPIs, PPIs, and SGIs. The default implementations for GICv2 and
GICv3 follows interrupt numbering as specified by the ARM GIC
architecture.

API documentation updated.

Change-Id: Ia6aa379dc955994333232e6138f259535d4fa087
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

1 files changed, 39 insertions, 0 deletions

diff --git a/docs/platform-interrupt-controller-API.rst b/docs/platform-interrupt-controller-API.rst
index 9ef2e3f6..a94a90c7 100644
--- a/docs/platform-interrupt-controller-API.rst
+++ b/docs/platform-interrupt-controller-API.rst
@@ -27,6 +27,45 @@ acknowledged via. ``plat_ic_acknowledge_interrupt``.
 In the case of ARM standard platforms using GIC, the *Running Priority Register*
 is read to determine the priority of the interrupt.
 
+Function: int plat_ic_is_spi(unsigned int id); [optional]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+::
+
+    Argument : unsigned int
+    Return   : int
+
+The API should return whether the interrupt ID (first parameter) is categorized
+as a Shared Peripheral Interrupt. Shared Peripheral Interrupts are typically
+associated to system-wide peripherals, and these interrupts can target any PE in
+the system.
+
+Function: int plat_ic_is_ppi(unsigned int id); [optional]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+::
+
+    Argument : unsigned int
+    Return   : int
+
+The API should return whether the interrupt ID (first parameter) is categorized
+as a Private Peripheral Interrupt. Private Peripheral Interrupts are typically
+associated with peripherals that are private to each PE. Interrupts from private
+peripherals target to that PE only.
+
+Function: int plat_ic_is_sgi(unsigned int id); [optional]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+::
+
+    Argument : unsigned int
+    Return   : int
+
+The API should return whether the interrupt ID (first parameter) is categorized
+as a Software Generated Interrupt. Software Generated Interrupts are raised by
+explicit programming by software, and are typically used in inter-PE
+communication. Secure SGIs are reserved for use by Secure world software.
+
 ----
 
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