Merge pull request #1130 from jeenu-arm/gic-patches

New GIC APIs and specifying interrupt propertes

4 files changed, 365 insertions, 1 deletions

diff --git a/docs/firmware-design.rst b/docs/firmware-design.rst
index e16e9b89..07905975 100644
--- a/docs/firmware-design.rst
+++ b/docs/firmware-design.rst
@@ -1167,6 +1167,56 @@ In other words, the reset handler should be able to detect whether an action has
 already been performed and act as appropriate. Possible courses of actions are,
 e.g. skip the action the second time, or undo/redo it.
 
+Configuring secure interrupts
+-----------------------------
+
+The GIC driver is responsible for performing initial configuration of secure
+interrupts on the platform. To this end, the platform is expected to provide the
+GIC driver (either GICv2 or GICv3, as selected by the platform) with the
+interrupt configuration during the driver initialisation.
+
+There are two ways to specify secure interrupt configuration:
+
+#. Array of secure interrupt properties: In this scheme, in both GICv2 and GICv3
+   driver data structures, the ``interrupt_props`` member points to an array of
+   interrupt properties. Each element of the array specifies the interrupt
+   number and its configuration, viz. priority, group, configuration. Each
+   element of the array shall be populated by the macro ``INTR_PROP_DESC()``.
+   The macro takes the following arguments:
+
+   -  10-bit interrupt number,
+
+   -  8-bit interrupt priority,
+
+   -  Interrupt type (one of ``INTR_TYPE_EL3``, ``INTR_TYPE_S_EL1``,
+      ``INTR_TYPE_NS``),
+
+   -  Interrupt configuration (either ``GIC_INTR_CFG_LEVEL`` or
+      ``GIC_INTR_CFG_EDGE``).
+
+#. Array of secure interrupts: In this scheme, the GIC driver is provided an
+   array of secure interrupt numbers. The GIC driver, at the time of
+   initialisation, iterates through the array and assigns each interrupt
+   the appropriate group.
+
+   -  For the GICv2 driver, in ``gicv2_driver_data`` structure, the
+      ``g0_interrupt_array`` member of the should point to the array of
+      interrupts to be assigned to *Group 0*, and the ``g0_interrupt_num``
+      member of the should be set to the number of interrupts in the array.
+
+   -  For the GICv3 driver, in ``gicv3_driver_data`` structure:
+
+      -  The ``g0_interrupt_array`` member of the should point to the array of
+         interrupts to be assigned to *Group 0*, and the ``g0_interrupt_num``
+         member of the should be set to the number of interrupts in the array.
+
+      -  The ``g1s_interrupt_array`` member of the should point to the array of
+         interrupts to be assigned to *Group 1 Secure*, and the
+         ``g1s_interrupt_num`` member of the should be set to the number of
+         interrupts in the array.
+
+   **Note that this scheme is deprecated.**
+
 CPU specific operations framework
 ---------------------------------
 
diff --git a/docs/platform-interrupt-controller-API.rst b/docs/platform-interrupt-controller-API.rst
new file mode 100644
index 00000000..795c0856
--- /dev/null
+++ b/docs/platform-interrupt-controller-API.rst
@@ -0,0 +1,297 @@
+Platform Interrupt Controller API documentation
+===============================================
+
+.. section-numbering::
+    :suffix: .
+
+.. contents::
+
+This document lists the optional platform interrupt controller API that
+abstracts the runtime configuration and control of interrupt controller from the
+generic code. The mandatory APIs are described in the `porting guide`__.
+
+.. __: porting-guide.rst#interrupt-management-framework-in-bl31
+
+Function: unsigned int plat_ic_get_running_priority(void); [optional]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+::
+
+    Argument : void
+    Return   : unsigned int
+
+This API should return the priority of the interrupt the PE is currently
+servicing. This must be be called only after an interrupt has already been
+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.
+
+Function: unsigned int plat_ic_get_interrupt_active(unsigned int id); [optional]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+::
+
+    Argument : unsigned int
+    Return   : int
+
+This API should return the *active* status of the interrupt ID specified by the
+first parameter, ``id``.
+
+In case of ARM standard platforms using GIC, the implementation of the API reads
+the GIC *Set Active Register* to read and return the active status of the
+interrupt.
+
+Function: void plat_ic_enable_interrupt(unsigned int id); [optional]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+::
+
+    Argument : unsigned int
+    Return   : void
+
+This API should enable the interrupt ID specified by the first parameter,
+``id``. PEs in the system are expected to receive only enabled interrupts.
+
+In case of ARM standard platforms using GIC, the implementation of the API
+inserts barrier to make memory updates visible before enabling interrupt, and
+then writes to GIC *Set Enable Register* to enable the interrupt.
+
+Function: void plat_ic_disable_interrupt(unsigned int id); [optional]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+::
+
+    Argument : unsigned int
+    Return   : void
+
+This API should disable the interrupt ID specified by the first parameter,
+``id``. PEs in the system are not expected to receive disabled interrupts.
+
+In case of ARM standard platforms using GIC, the implementation of the API
+writes to GIC *Clear Enable Register* to disable the interrupt, and inserts
+barrier to make memory updates visible afterwards.
+
+Function: void plat_ic_set_interrupt_priority(unsigned int id, unsigned int priority); [optional]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+::
+
+    Argument : unsigned int
+    Argument : unsigned int
+    Return   : void
+
+This API should set the priority of the interrupt specified by first parameter
+``id`` to the value set by the second parameter ``priority``.
+
+In case of ARM standard platforms using GIC, the implementation of the API
+writes to GIC *Priority Register* set interrupt priority.
+
+Function: int plat_ic_has_interrupt_type(unsigned int type); [optional]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+::
+
+    Argument : unsigned int
+    Return   : int
+
+This API should return whether the platform supports a given interrupt type. The
+parameter ``type`` shall be one of ``INTR_TYPE_EL3``, ``INTR_TYPE_S_EL1``, or
+``INTR_TYPE_NS``.
+
+In case of ARM standard platforms using GICv3, the implementation of the API
+returns ``1`` for all interrupt types.
+
+In case of ARM standard platforms using GICv2, the API always return ``1`` for
+``INTR_TYPE_NS``. Return value for other types depends on the value of build
+option ``GICV2_G0_FOR_EL3``:
+
+- For interrupt type ``INTR_TYPE_EL3``:
+
+  - When ``GICV2_G0_FOR_EL3`` is ``0``, it returns ``0``, indicating no support
+    for EL3 interrupts.
+
+  - When ``GICV2_G0_FOR_EL3`` is ``1``, it returns ``1``, indicating support for
+    EL3 interrupts.
+
+- For interrupt type ``INTR_TYPE_S_EL1``:
+
+  - When ``GICV2_G0_FOR_EL3`` is ``0``, it returns ``1``, indicating support for
+    Secure EL1 interrupts.
+
+  - When ``GICV2_G0_FOR_EL3`` is ``1``, it returns ``0``, indicating no support
+    for Secure EL1 interrupts.
+
+Function: void plat_ic_set_interrupt_type(unsigned int id, unsigned int type); [optional]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+::
+
+    Argument : unsigned int
+    Argument : unsigned int
+    Return   : void
+
+This API should set the interrupt specified by first parameter ``id`` to the
+type specified by second parameter ``type``. The ``type`` parameter can be
+one of:
+
+- ``INTR_TYPE_NS``: interrupt is meant to be consumed by the Non-secure world.
+
+- ``INTR_TYPE_S_EL1``: interrupt is meant to be consumed by Secure EL1.
+
+- ``INTR_TYPE_EL3``: interrupt is meant to be consumed by EL3.
+
+In case of ARM standard platforms using GIC, the implementation of the API
+writes to the GIC *Group Register* and *Group Modifier Register* (only GICv3) to
+assign the interrupt to the right group.
+
+For GICv3:
+
+- ``INTR_TYPE_NS`` maps to Group 1 interrupt.
+
+- ``INTR_TYPE_S_EL1`` maps to Secure Group 1 interrupt.
+
+- ``INTR_TYPE_EL3`` maps to Secure Group 0 interrupt.
+
+For GICv2:
+
+- ``INTR_TYPE_NS`` maps to Group 1 interrupt.
+
+- When the build option ``GICV2_G0_FOR_EL3`` is set to ``0`` (the default),
+  ``INTR_TYPE_S_EL1`` maps to Group 0. Otherwise, ``INTR_TYPE_EL3`` maps to
+  Group 0 interrupt.
+
+Function: void plat_ic_raise_el3_sgi(int sgi_num, u_register_t target); [optional]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+::
+
+    Argument : int
+    Argument : u_register_t
+    Return   : void
+
+This API should raise an EL3 SGI. The first parameter, ``sgi_num``, specifies
+the ID of the SGI. The second parameter, ``target``, must be the MPIDR of the
+target PE.
+
+In case of ARM standard platforms using GIC, the implementation of the API
+inserts barrier to make memory updates visible before raising SGI, then writes
+to appropriate *SGI Register* in order to raise the EL3 SGI.
+
+Function: void plat_ic_set_spi_routing(unsigned int id, unsigned int routing_mode, u_register_t mpidr); [optional]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+::
+
+    Argument : unsigned int
+    Argument : unsigned int
+    Argument : u_register_t
+    Return   : void
+
+This API should set the routing mode of Share Peripheral Interrupt (SPI)
+specified by first parameter ``id`` to that specified by the second parameter
+``routing_mode``.
+
+The ``routing_mode`` parameter can be one of:
+
+- ``INTR_ROUTING_MODE_ANY`` means the interrupt can be routed to any PE in the
+  system. The ``mpidr`` parameter is ignored in this case.
+
+- ``INTR_ROUTING_MODE_PE`` means the interrupt is routed to the PE whose MPIDR
+  value is specified by the parameter ``mpidr``.
+
+In case of ARM standard platforms using GIC, the implementation of the API
+writes to the GIC *Target Register* (GICv2) or *Route Register* (GICv3) to set
+the routing.
+
+Function: void plat_ic_set_interrupt_pending(unsigned int id); [optional]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+::
+
+    Argument : unsigned int
+    Return   : void
+
+This API should set the interrupt specified by first parameter ``id`` to
+*Pending*.
+
+In case of ARM standard platforms using GIC, the implementation of the API
+inserts barrier to make memory updates visible before setting interrupt pending,
+and writes to the GIC *Set Pending Register* to set the interrupt pending
+status.
+
+Function: void plat_ic_clear_interrupt_pending(unsigned int id); [optional]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+::
+
+    Argument : unsigned int
+    Return   : void
+
+This API should clear the *Pending* status of the interrupt specified by first
+parameter ``id``.
+
+In case of ARM standard platforms using GIC, the implementation of the API
+writes to the GIC *Clear Pending Register* to clear the interrupt pending
+status, and inserts barrier to make memory updates visible afterwards.
+
+Function: unsigned int plat_ic_set_priority_mask(unsigned int id); [optional]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+::
+
+    Argument : unsigned int
+    Return   : int
+
+This API should set the priority mask (first parameter) in the interrupt
+controller such that only interrupts of higher priority than the supplied one
+may be signalled to the PE. The API should return the current priority value
+that it's overwriting.
+
+In case of ARM standard platforms using GIC, the implementation of the API
+inserts to order memory updates before updating mask, then writes to the GIC
+*Priority Mask Register*, and make sure memory updates are visible before
+potential trigger due to mask update.
+
+----
+
+*Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.*
diff --git a/docs/porting-guide.rst b/docs/porting-guide.rst
index cd3bcdae..6352bb95 100644
--- a/docs/porting-guide.rst
+++ b/docs/porting-guide.rst
@@ -2327,6 +2327,10 @@ Standard layer to use GICv2 and the FVP can be configured to use either GICv2 or
 GICv3 depending on the build flag ``FVP_USE_GIC_DRIVER`` (See FVP platform
 specific build options in `User Guide`_ for more details).
 
+See also: `Interrupt Controller Abstraction APIs`__.
+
+.. __: platform-interrupt-controller-API.rst
+
 Function : plat\_interrupt\_type\_to\_line() [mandatory]
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
@@ -2674,7 +2678,7 @@ amount of open resources per driver.
 
 --------------
 
-*Copyright (c) 2013-2016, ARM Limited and Contributors. All rights reserved.*
+*Copyright (c) 2013-2017, ARM Limited and Contributors. All rights reserved.*
 
 .. _Migration Guide: platform-migration-guide.rst
 .. _include/plat/common/platform.h: ../include/plat/common/platform.h
diff --git a/docs/user-guide.rst b/docs/user-guide.rst
index 7c0a980f..28483f2b 100644
--- a/docs/user-guide.rst
+++ b/docs/user-guide.rst
@@ -386,6 +386,19 @@ Common build options
    images will include support for Trusted Board Boot, but the FIP and FWU\_FIP
    will not include the corresponding certificates, causing a boot failure.
 
+-  ``GICV2_G0_FOR_EL3``: Unlike GICv3, the GICv2 architecture doesn't have
+   inherent support for specific EL3 type interrupts. Setting this build option
+   to ``1`` assumes GICv2 *Group 0* interrupts are expected to target EL3, both
+   by `platform abstraction layer`__ and `Interrupt Management Framework`__.
+   This allows GICv2 platforms to enable features requiring EL3 interrupt type.
+   This also means that all GICv2 Group 0 interrupts are delivered to EL3, and
+   the Secure Payload interrupts needs to be synchronously handed over to Secure
+   EL1 for handling. The default value of this option is ``0``, which means the
+   Group 0 interrupts are assumed to be handled by Secure EL1.
+
+   .. __: `platform-interrupt-controller-API.rst`
+   .. __: `interrupt-framework-design.rst`
+
 -  ``HANDLE_EA_EL3_FIRST``: When defined External Aborts and SError Interrupts
    will be always trapped in EL3 i.e. in BL31 at runtime.