On 11/26/18 1:56 PM, Peng Hao wrote:
Add mmio support info in docs/specs/pvpanic.txt.
Signed-off-by: Peng Hao <peng.h...@zte.com.cn>
---
docs/specs/pvpanic.txt | 15 +++++++++++++--
1 file changed, 13 insertions(+), 2 deletions(-)
diff --git a/docs/specs/pvpanic.txt b/docs/specs/pvpanic.txt
index c7bbacc..67f5591 100644
--- a/docs/specs/pvpanic.txt
+++ b/docs/specs/pvpanic.txt
@@ -1,14 +1,18 @@
PVPANIC DEVICE
==============
-pvpanic device is a simulated ISA device, through which a guest panic
-event is sent to qemu, and a QMP event is generated. This allows
+pvpanic device is a simulated ISA/SysBus device, through which a guest
+panic event is sent to qemu, and a QMP event is generated. This allows
management apps (e.g. libvirt) to be notified and respond to the event.
The management app has the option of waiting for GUEST_PANICKED events,
and/or polling for guest-panicked RunState, to learn when the pvpanic
device has fired a panic event.
+When pvpanic device is implemented as a ISA device, it supports IOPORT
+mode. Since QEMU v3.2 pvpanic also supports MMIO mode, it will be
The next qemu release will be 4.0, not 3.2.
+implemented as a SYSBUS device.
Grammar suggestion:
The pvpanic device can be implemented as an ISA device (using IOPORT),
or, since qemu 4.0, as a SYSBUS device (using MMIO).
+
ISA Interface
-------------
@@ -19,6 +23,13 @@ Software should set only bits both itself and the device recognize.
Currently, only bit 0 is recognized, setting it indicates a guest panic
has happened.
+SYSBUS Interface
+----------------
+
+The SYSBUS interface is similar to the ISA interface except that it uses
+MMIO. For example, the arm virt machine could put the pvpanic device at
+[0x9070000, 0x9070001] and currently only the first byte is used.
+
ACPI Interface
--------------
--
Eric Blake, Principal Software Engineer
Red Hat, Inc. +1-919-301-3266
Virtualization: qemu.org | libvirt.org