To complete the event routing, the IVRE sub-engine uses a second table
containing Event Notification Descriptor (END) structures.
An END specifies on which Event Queue (EQ) the event notification
data, defined in the associated EAS, should be posted when an
exception occurs. It also defines which Notification Virtual Target
(NVT) should be notified.
The Event Queue is a memory page provided by the O/S defining a
circular buffer, one per server and priority couple, containing Event
Queue entries. These are 4 bytes long, the first bit being a
'generation' bit and the 31 following bits the END Data field. They
are pulled by the O/S when the exception occurs.
The END Data field is a way to set an invariant logical event source
number for an IRQ. On sPAPR machines, it is set with the
H_INT_SET_SOURCE_CONFIG hcall when the EISN flag is used.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
[dwg: Fold in a later fix from Cédric fixing field accessors]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The XiveRouter models the second sub-engine of the XIVE architecture :
the Interrupt Virtualization Routing Engine (IVRE).
The IVRE handles event notifications of the IVSE and performs the
interrupt routing process. For this purpose, it uses a set of tables
stored in system memory, the first of which being the Event Assignment
Structure (EAS) table.
The EAT associates an interrupt source number with an Event Notification
Descriptor (END) which will be used in a second phase of the routing
process to identify a Notification Virtual Target.
The XiveRouter is an abstract class which needs to be inherited from
to define a storage for the EAT, and other upcoming tables.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
[dwg: Folded in parts of a later fix by Cédric fixing field access]
[dwg: Fix style nits]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The XiveNotifier offers a simple interface, between the XiveSource
object and the main interrupt controller of the machine. It will
forward event notifications to the XIVE Interrupt Virtualization
Routing Engine (IVRE).
Signed-off-by: Cédric Le Goater <clg@kaod.org>
[dwg: Adjust type name string for XiveNotifier]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The 'sent' status of the LSI interrupt source is modeled with the 'P'
bit of the ESB and the assertion status of the source is maintained
with an extra bit under the main XiveSource object. The type of the
source is stored in the same array for practical reasons.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
[dwg: Fix style nit]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The first sub-engine of the overall XIVE architecture is the Interrupt
Virtualization Source Engine (IVSE). An IVSE can be integrated into
another logic, like in a PCI PHB or in the main interrupt controller
to manage IPIs.
Each IVSE instance is associated with an Event State Buffer (ESB) that
contains a two bit state entry for each possible event source. When an
event is signaled to the IVSE, by MMIO or some other means, the
associated interrupt state bits are fetched from the ESB and
modified. Depending on the resulting ESB state, the event is forwarded
to the IVRE sub-engine of the controller doing the routing.
Each supported ESB entry is associated with either a single or a
even/odd pair of pages which provides commands to manage the source:
to EOI, to turn off the source for instance.
On a sPAPR machine, the O/S will obtain the page address of the ESB
entry associated with a source and its characteristic using the
H_INT_GET_SOURCE_INFO hcall. On PowerNV, a similar OPAL call is used.
The xive_source_notify() routine is in charge forwarding the source
event notification to the routing engine. It will be filled later on.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
