Docs: Added information on IRQ implementations
Described IRQ source in more detail
Pointed to files which contain relavent information
Signed-off-by: Boris Deletic <boris.deletic@arm.com>
Change-Id: Ie75962e9ba2a42383b56701d82bb9031b88f2f67
diff --git a/docs/getting_started/tfm_secure_irq_handling.rst b/docs/getting_started/tfm_secure_irq_handling.rst
index bde9a25..8cd664e 100644
--- a/docs/getting_started/tfm_secure_irq_handling.rst
+++ b/docs/getting_started/tfm_secure_irq_handling.rst
@@ -46,10 +46,14 @@
An IRQ handler is defined by the following nodes:
-- ``source``: The IRQ number or the name IRQ line. With the name of the IRQ
- line, there must be defined a macro in ``tfm_peripherals_def.h`` which is
- substituted to the IRQ line num.
-- ``signal`` The name of the signal for this IRQ
+- ``source``: The IRQ number or the name of the IRQ line. With the name of the
+ IRQ line, there must be defined a macro in ``tfm_peripherals_def.h`` which is
+ substituted to the IRQ line num. The IRQ line nums and sources are defined by
+ each platform: for example, they are defined in ``platform_irq.h`` for the
+ Musca-S1 platform. When defining new macros in ``tfm_peripherals_def.h``, it
+ is important the macro name matches the platform's handler function for that
+ IRQ source.
+- ``signal``: The name of the signal for this IRQ.
- ``tfm_irq_priority``: The priority of the IRQ. This number must be in the
range [0-255] inclusive. Please note that some of the less significant bits of
this value might be dropped based on the number of priority bits implemented
@@ -65,8 +69,11 @@
- In case ``source`` is defined IRQ macro, the name of the handler becomes
``void <macro>_Handler(void)``.
- This is important, because the derived name have to be present in the vector
- table as the handler of the IRQ.
+ This is important, because the derived name has to be present in the vector
+ table as the handler of the IRQ. The platform startup functions are specified
+ in the vector table defined in the platform secure startup file. The user
+ should verify the names of the generated handlers match for a given platform
+ IRQ.
.. Note::
@@ -172,4 +179,4 @@
--------------
-*Copyright (c) 2018-2019, Arm Limited. All rights reserved.*
+*Copyright (c) 2018-2020, Arm Limited. All rights reserved.*