[Qemu-devel] [PULL 25/42] ppc/xive: Provide escalation support

David Gibson posted 42 patches 6 years, 5 months ago
Maintainers: Halil Pasic <pasic@linux.ibm.com>, "Marc-André Lureau" <marcandre.lureau@redhat.com>, Marcel Apfelbaum <marcel.apfelbaum@gmail.com>, Eduardo Habkost <ehabkost@redhat.com>, David Gibson <david@gibson.dropbear.id.au>, David Hildenbrand <david@redhat.com>, "Cédric Le Goater" <clg@kaod.org>, Richard Henderson <rth@twiddle.net>, Peter Maydell <peter.maydell@linaro.org>, Paolo Bonzini <pbonzini@redhat.com>, Cornelia Huck <cohuck@redhat.com>, "Michael S. Tsirkin" <mst@redhat.com>, Christian Borntraeger <borntraeger@de.ibm.com>
[Qemu-devel] [PULL 25/42] ppc/xive: Provide escalation support
Posted by David Gibson 6 years, 5 months ago
From: Cédric Le Goater <clg@kaod.org>

If the XIVE presenter can not find the NVT dispatched on any of the HW
threads, it can not deliver the interrupt. XIVE offers an escalation
mechanism to handle such scenarios and inform the hypervisor that an
action should be taken.

Escalation is configured by setting the 'e' bit and the EAS in word 4
& 5 to let the HW look for the escalation END on which to trigger a
new event.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20190718115420.19919-6-clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
---
 hw/intc/xive.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/hw/intc/xive.c b/hw/intc/xive.c
index f27b4e3328..12f0d09df6 100644
--- a/hw/intc/xive.c
+++ b/hw/intc/xive.c
@@ -1549,6 +1549,22 @@ static void xive_router_end_notify(XiveRouter *xrtr, uint8_t end_blk,
          * On HW, follows a "Broadcast Backlog" to IVPEs
          */
     }
+
+    /*
+     * If activated, escalate notification using the ESe PQ bits and
+     * the EAS in w4-5
+     */
+    if (!xive_end_is_escalate(&end)) {
+        return;
+    }
+
+    /*
+     * The END trigger becomes an Escalation trigger
+     */
+    xive_router_end_notify(xrtr,
+                           xive_get_field32(END_W4_ESC_END_BLOCK, end.w4),
+                           xive_get_field32(END_W4_ESC_END_INDEX, end.w4),
+                           xive_get_field32(END_W5_ESC_END_DATA,  end.w5));
 }
 
 void xive_router_notify(XiveNotifier *xn, uint32_t lisn)
-- 
2.21.0