linux-stable/arch/powerpc/sysdev/xive
Ram Pai 094235222d powerpc/xive: Share the event-queue page with the Hypervisor.
XIVE interrupt controller uses an Event Queue (EQ) to enqueue event
notifications when an exception occurs. The EQ is a single memory page
provided by the O/S defining a circular buffer, one per server and
priority couple.

On baremetal, the EQ page is configured with an OPAL call. On pseries,
an extra hop is necessary and the guest OS uses the hcall
H_INT_SET_QUEUE_CONFIG to configure the XIVE interrupt controller.

The XIVE controller being Hypervisor privileged, it will not be allowed
to enqueue event notifications for a Secure VM unless the EQ pages are
shared by the Secure VM.

Hypervisor/Ultravisor still requires support for the TIMA and ESB page
fault handlers. Until this is complete, QEMU can use the emulated XIVE
device for Secure VMs, option "kernel_irqchip=off" on the QEMU pseries
machine.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Reviewed-by: Cedric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200426020518.GC5853@oc0525413822.ibm.com
2020-05-28 23:24:40 +10:00
..
common.c powerpc/xive: Do not expose a debugfs file when XIVE is disabled 2020-05-28 23:24:32 +10:00
Kconfig powerpc: remove redundant 'default n' from Kconfig-s 2018-10-13 22:21:25 +11:00
Makefile treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
native.c powerpc/xive: Define xive_native_alloc_irq_on_chip() 2020-04-20 16:52:59 +10:00
spapr.c powerpc/xive: Share the event-queue page with the Hypervisor. 2020-05-28 23:24:40 +10:00
xive-internal.h powerpc/xive: Add a debugfs file to dump internal XIVE state 2020-03-27 00:20:38 +11:00