Commit Graph

56 Commits

Author SHA1 Message Date
Cédric Le Goater
a0c493ae67 spapr/xive: simplify the sPAPR IRQ qirq method for XIVE
The qirq routines of the XiveSource and the sPAPRXive model are only
used under the sPAPR IRQ backend. Simplify the overall call stack and
gather all the code under spapr_qirq_xive(). It will ease future
changes.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-01-09 09:28:14 +11:00
Cédric Le Goater
b2e2247716 spapr: add a 'reset' method to the sPAPR IRQ backend
For the time being, the XIVE reset handler updates the OS CAM line of
the vCPU as it is done under a real hypervisor when a vCPU is
scheduled to run on a HW thread. This will let the XIVE presenter
engine find a match among the NVTs dispatched on the HW threads.

This handler will become even more useful when we introduce the
machine supporting both interrupt modes, XIVE and XICS. In this
machine, the interrupt mode is chosen by the CAS negotiation process
and activated after a reset.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
[dwg: Fix style nits]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-12-21 09:40:35 +11:00
Cédric Le Goater
6e21de4a50 spapr: add device tree support for the XIVE exploitation mode
The XIVE interface for the guest is described in the device tree under
the "interrupt-controller" node. A couple of new properties are
specific to XIVE :

 - "reg"

   contains the base address and size of the thread interrupt
   managnement areas (TIMA), for the User level and for the Guest OS
   level. Only the Guest OS level is taken into account today.

 - "ibm,xive-eq-sizes"

   the size of the event queues. One cell per size supported, contains
   log2 of size, in ascending order.

 - "ibm,xive-lisn-ranges"

   the IRQ interrupt number ranges assigned to the guest for the IPIs.

and also under the root node :

 - "ibm,plat-res-int-priorities"

   contains a list of priorities that the hypervisor has reserved for
   its own use. OPAL uses the priority 7 queue to automatically
   escalate interrupts for all other queues (DD2.X POWER9). So only
   priorities [0..6] are allowed for the guest.

Extend the sPAPR IRQ backend with a new handler to populate the DT
with the appropriate "interrupt-controller" node.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
[dwg: Fix style nits]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-12-21 09:39:07 +11:00
Cédric Le Goater
23bcd5eb9a spapr: add hcalls support for the XIVE exploitation interrupt mode
The different XIVE virtualization structures (sources and event queues)
are configured with a set of Hypervisor calls :

 - H_INT_GET_SOURCE_INFO

   used to obtain the address of the MMIO page of the Event State
   Buffer (ESB) entry associated with the source.

 - H_INT_SET_SOURCE_CONFIG

   assigns a source to a "target".

 - H_INT_GET_SOURCE_CONFIG

   determines which "target" and "priority" is assigned to a source

 - H_INT_GET_QUEUE_INFO

   returns the address of the notification management page associated
   with the specified "target" and "priority".

 - H_INT_SET_QUEUE_CONFIG

   sets or resets the event queue for a given "target" and "priority".
   It is also used to set the notification configuration associated
   with the queue, only unconditional notification is supported for
   the moment. Reset is performed with a queue size of 0 and queueing
   is disabled in that case.

 - H_INT_GET_QUEUE_CONFIG

   returns the queue settings for a given "target" and "priority".

 - H_INT_RESET

   resets all of the guest's internal interrupt structures to their
   initial state, losing all configuration set via the hcalls
   H_INT_SET_SOURCE_CONFIG and H_INT_SET_QUEUE_CONFIG.

 - H_INT_SYNC

   issue a synchronisation on a source to make sure all notifications
   have reached their queue.

Calls that still need to be addressed :

   H_INT_SET_OS_REPORTING_LINE
   H_INT_GET_OS_REPORTING_LINE

See the code for more documentation on each hcall.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
[dwg: Folded in fix for field accessors]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-12-21 09:37:38 +11:00
Cédric Le Goater
0cddee8d48 spapr/xive: use the VCPU id as a NVT identifier
The IVPE scans the O/S CAM line of the XIVE thread interrupt contexts
to find a matching Notification Virtual Target (NVT) among the NVTs
dispatched on the HW processor threads.

On a real system, the thread interrupt contexts are updated by the
hypervisor when a Virtual Processor is scheduled to run on a HW
thread. Under QEMU, the model will emulate the same behavior by
hardwiring the NVT identifier in the thread context registers at
reset.

The NVT identifier used by the sPAPRXive model is the VCPU id. The END
identifier is also derived from the VCPU id. A set of helpers doing
the conversion between identifiers are provided for the hcalls
configuring the sources and the ENDs.

The model does not need a NVT table but the XiveRouter NVT operations
are provided to perform some extra checks in the routing algorithm.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-12-21 09:37:38 +11:00
Cédric Le Goater
3aa597f650 spapr/xive: introduce a XIVE interrupt controller
sPAPRXive models the XIVE interrupt controller of the sPAPR machine.
It inherits from the XiveRouter and provisions storage for the routing
tables :

  - Event Assignment Structure (EAS)
  - Event Notification Descriptor (END)

The sPAPRXive model incorporates an internal XiveSource for the IPIs
and for the interrupts of the virtual devices of the guest. This model
is consistent with XIVE architecture which also incorporates an
internal IVSE for IPIs and accelerator interrupts in the IVRE
sub-engine.

The sPAPRXive model exports two memory regions, one for the ESB
trigger and management pages used to control the sources and one for
the TIMA pages. They are mapped by default at the addresses found on
chip 0 of a baremetal system. This is also consistent with the XIVE
architecture which defines a Virtualization Controller BAR for the
internal IVSE ESB pages and a Thread Managment BAR for the TIMA.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
[dwg: Fold in field accessor fixes]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-12-21 09:37:38 +11:00