Re: [Qemu-devel] [PATCH V10 7/9] hw/misc/pvpanic: preparing for adding configure interface

2018-12-01 Thread peng.hao2
>On Wed, 28 Nov 2018 at 03:50, Peng Hao  wrote:
>>
>> Prepare for pvpanic-mmio configure interface.
>>
>> Signed-off-by: Peng Hao 
>> ---
>>  hw/arm/sysbus-fdt.c |  2 ++
>>  hw/arm/virt.c   |  2 ++
>>  hw/misc/pvpanic.c   | 11 +--
>>  3 files changed, 13 insertions(+), 2 deletions(-)
>
>This looks rather odd. The sysbus-fdt.c code is for
>handling devices that we must pass through from the
>host system (including pulling in device tree fragments
>from the host). The pvpanic device isn't a host pass
>through device so I don't think it should be touching
>that code at all. It's just a simple MMIO device.
>
>I suspect the reason you've done this is that you're
>trying to get "-device pvpanic" to work on the command
>line. I recommend not trying to get that to work.
>MMIO devices are not pluggable devices, and -device
>is not expected to work with them.
>
yes, I use -device pvpanic-mmio. Thank you for pointing this out.
 I also felt a little odd when I realized it. But I didn't think about the 
reason.
I think I can use a way like iommu, and I've thought about it in doing my 
current way.
thanks.
>thanks
>-- PMM

Re: [Qemu-devel] [PATCH V10 7/9] hw/misc/pvpanic: preparing for adding configure interface

2018-11-30 Thread Peter Maydell
On Fri, 30 Nov 2018 at 16:14, Andrew Jones  wrote:
>
> On Fri, Nov 30, 2018 at 03:57:13PM +, Peter Maydell wrote:
> > On Fri, 30 Nov 2018 at 15:56, Peter Maydell  
> > wrote:
> > > I suspect the reason you've done this is that you're
> > > trying to get "-device pvpanic" to work on the command
> > > line. I recommend not trying to get that to work.
> > > MMIO devices are not pluggable devices, and -device
> > > is not expected to work with them.
> >
> > If you do want a pluggable pvpanic device for the virt
> > board then you should implement it as a PCI device,
> > incidentally.
> >
>
> We'd have to allocate it a PCI device ID, but I guess that's OK as
> there are plenty of IDs left for 1b36. I'm not sure it's worth it
> though. Phil asked that this device by user creatable, but maybe
> that's not necessary. Maybe we just need a mach-virt compat boolean
> and then to always provide this device for 4.0 and later machines?

Yes, if it's just an mmio device then we should either:
 * default to providing it, with the usual flag to say "don't create
   in older virt board versions", and also a machine property to
   disable it manually (like we do with the ITS)
 * default to not providing it at all, and have a machine
   property to enable it (like we do with the IOMMU)
Which is all doable, but every time we do that it makes the
virt board code that extra bit more complicated (we have
half a dozen machine properties on it already).

This kind of thing is why a PCI device is cleaner -- it just
works on any machine with a PCI controller, it by default is
something that the user can provide if they want to and not if
they don't, and it's not a custom UI that management layers
might need to special-case. The guest does need to do a bit
of PCI probing and setup initially, but then it can just leave
the MMIO BAR permanently mapped and write to that address
when the guest panics.

thanks
-- PMM



Re: [Qemu-devel] [PATCH V10 7/9] hw/misc/pvpanic: preparing for adding configure interface

2018-11-30 Thread Andrew Jones
On Fri, Nov 30, 2018 at 03:57:13PM +, Peter Maydell wrote:
> On Fri, 30 Nov 2018 at 15:56, Peter Maydell  wrote:
> > I suspect the reason you've done this is that you're
> > trying to get "-device pvpanic" to work on the command
> > line. I recommend not trying to get that to work.
> > MMIO devices are not pluggable devices, and -device
> > is not expected to work with them.
> 
> If you do want a pluggable pvpanic device for the virt
> board then you should implement it as a PCI device,
> incidentally.
>

We'd have to allocate it a PCI device ID, but I guess that's OK as
there are plenty of IDs left for 1b36. I'm not sure it's worth it
though. Phil asked that this device by user creatable, but maybe
that's not necessary. Maybe we just need a mach-virt compat boolean
and then to always provide this device for 4.0 and later machines?

Thanks,
drew



Re: [Qemu-devel] [PATCH V10 7/9] hw/misc/pvpanic: preparing for adding configure interface

2018-11-30 Thread Peter Maydell
On Fri, 30 Nov 2018 at 15:56, Peter Maydell  wrote:
> I suspect the reason you've done this is that you're
> trying to get "-device pvpanic" to work on the command
> line. I recommend not trying to get that to work.
> MMIO devices are not pluggable devices, and -device
> is not expected to work with them.

If you do want a pluggable pvpanic device for the virt
board then you should implement it as a PCI device,
incidentally.

thanks
-- PMM



Re: [Qemu-devel] [PATCH V10 7/9] hw/misc/pvpanic: preparing for adding configure interface

2018-11-30 Thread Peter Maydell
On Wed, 28 Nov 2018 at 03:50, Peng Hao  wrote:
>
> Prepare for pvpanic-mmio configure interface.
>
> Signed-off-by: Peng Hao 
> ---
>  hw/arm/sysbus-fdt.c |  2 ++
>  hw/arm/virt.c   |  2 ++
>  hw/misc/pvpanic.c   | 11 +--
>  3 files changed, 13 insertions(+), 2 deletions(-)

This looks rather odd. The sysbus-fdt.c code is for
handling devices that we must pass through from the
host system (including pulling in device tree fragments
from the host). The pvpanic device isn't a host pass
through device so I don't think it should be touching
that code at all. It's just a simple MMIO device.

I suspect the reason you've done this is that you're
trying to get "-device pvpanic" to work on the command
line. I recommend not trying to get that to work.
MMIO devices are not pluggable devices, and -device
is not expected to work with them.

thanks
-- PMM



[Qemu-devel] [PATCH V10 7/9] hw/misc/pvpanic: preparing for adding configure interface

2018-11-27 Thread Peng Hao
Prepare for pvpanic-mmio configure interface.

Signed-off-by: Peng Hao 
---
 hw/arm/sysbus-fdt.c |  2 ++
 hw/arm/virt.c   |  2 ++
 hw/misc/pvpanic.c   | 11 +--
 3 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/hw/arm/sysbus-fdt.c b/hw/arm/sysbus-fdt.c
index ad698d4..34577f3 100644
--- a/hw/arm/sysbus-fdt.c
+++ b/hw/arm/sysbus-fdt.c
@@ -38,6 +38,7 @@
 #include "hw/vfio/vfio-amd-xgbe.h"
 #include "hw/display/ramfb.h"
 #include "hw/arm/fdt.h"
+#include "hw/misc/pvpanic.h"
 
 /*
  * internal struct that contains the information to create dynamic
@@ -459,6 +460,7 @@ static const BindingEntry bindings[] = {
 VFIO_PLATFORM_BINDING("amd,xgbe-seattle-v1a", add_amd_xgbe_fdt_node),
 #endif
 TYPE_BINDING(TYPE_RAMFB_DEVICE, no_fdt_node),
+TYPE_BINDING(TYPE_PVPANIC_MMIO, no_fdt_node),
 TYPE_BINDING("", NULL), /* last element */
 };
 
diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index f2cb5de..1fd5941 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -59,6 +59,7 @@
 #include "qapi/visitor.h"
 #include "standard-headers/linux/input.h"
 #include "hw/arm/smmuv3.h"
+#include "hw/misc/pvpanic.h"
 
 #define DEFINE_VIRT_MACHINE_LATEST(major, minor, latest) \
 static void virt_##major##_##minor##_class_init(ObjectClass *oc, \
@@ -1783,6 +1784,7 @@ static void virt_machine_class_init(ObjectClass *oc, void 
*data)
 machine_class_allow_dynamic_sysbus_dev(mc, TYPE_VFIO_CALXEDA_XGMAC);
 machine_class_allow_dynamic_sysbus_dev(mc, TYPE_VFIO_AMD_XGBE);
 machine_class_allow_dynamic_sysbus_dev(mc, TYPE_RAMFB_DEVICE);
+machine_class_allow_dynamic_sysbus_dev(mc, TYPE_PVPANIC_MMIO);
 machine_class_allow_dynamic_sysbus_dev(mc, TYPE_VFIO_PLATFORM);
 mc->block_default_type = IF_VIRTIO;
 mc->no_cdrom = 1;
diff --git a/hw/misc/pvpanic.c b/hw/misc/pvpanic.c
index c9382a8..b6b5c89 100644
--- a/hw/misc/pvpanic.c
+++ b/hw/misc/pvpanic.c
@@ -67,7 +67,7 @@ typedef struct PVPanicISAState {
 typedef struct PVPanicMMIOState {
 SysBusDevice parent_obj;
 /**/
-
+uint32_t base;
 /* public */
 MemoryRegion mr;
 } PVPanicMMIOState;
@@ -151,10 +151,17 @@ static void pvpanic_mmio_initfn(Object *obj)
 sysbus_init_mmio(sbd, >mr);
 }
 
+static Property pvpanic_mmio_properties[] = {
+DEFINE_PROP_UINT32("mmio", PVPanicMMIOState, base, 0x0907),
+DEFINE_PROP_END_OF_LIST(),
+};
+
 static void pvpanic_mmio_class_init(ObjectClass *klass, void *data)
 {
 DeviceClass *dc = DEVICE_CLASS(klass);
-
+
+dc->user_creatable = true;
+dc->props = pvpanic_mmio_properties;
 set_bit(DEVICE_CATEGORY_MISC, dc->categories);
 }
 
-- 
1.8.3.1