Add mmio support info in docs/specs/pvpanic.txt. Reviewed-by: Andrew Jones <drjo...@redhat.com> Signed-off-by: Peng Hao <peng.h...@zte.com.cn> --- docs/specs/pvpanic.txt | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/docs/specs/pvpanic.txt b/docs/specs/pvpanic.txt index c7bbacc..994f080 100644 --- a/docs/specs/pvpanic.txt +++ b/docs/specs/pvpanic.txt @@ -1,7 +1,7 @@ PVPANIC DEVICE ============== -pvpanic device is a simulated ISA device, through which a guest panic +pvpanic device is a simulated 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. @@ -9,6 +9,9 @@ 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. +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 +22,13 @@ 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], where currently only the first byte is used. + ACPI Interface -------------- -- 1.8.3.1