Xen PCI passthrough fixes

[Xen-devel] [PATCH v3 3/3] OvmfPkg/XenSupport: turn off address decoding before BAR sizing

Posted by Igor Druzhinin 6 years, 9 months ago

On Xen, hvmloader firmware leaves address decoding enabled for
enumerated PCI device before jumping into OVMF. OVMF seems to
expect it to be disabled and tries to size PCI BARs in several places
without disabling it which causes BAR64, for example, being
incorrectly placed by QEMU.

Fix it by disabling PCI address decoding explicitly before the
first attempt to size BARs on Xen.

Signed-off-by: Igor Druzhinin <igor.druzhinin@citrix.com>
---
Changes in v3:
- dropped unused arguments and rename PcatPciRootBridgeDecoding function
- make mask application more clear as suggested
---
 OvmfPkg/Library/PciHostBridgeLib/XenSupport.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/OvmfPkg/Library/PciHostBridgeLib/XenSupport.c b/OvmfPkg/Library/PciHostBridgeLib/XenSupport.c
index 76fca53..b41bd6b 100644
--- a/OvmfPkg/Library/PciHostBridgeLib/XenSupport.c
+++ b/OvmfPkg/Library/PciHostBridgeLib/XenSupport.c
@@ -49,6 +49,22 @@ PcatPciRootBridgeBarExisted (
   EnableInterrupts ();
 }
 
+#define PCI_COMMAND_DECODE ((UINT16)(EFI_PCI_COMMAND_IO_SPACE | \
+                                     EFI_PCI_COMMAND_MEMORY_SPACE))
+STATIC
+VOID
+PcatPciRootBridgeDecodingDisable (
+  IN  UINTN                          Address
+  )
+{
+  UINT16                             Value;
+
+  Value = PciRead16 (Address);
+  if (Value & PCI_COMMAND_DECODE) {
+    PciWrite16 (Address, Value & ~(UINT32)PCI_COMMAND_DECODE);
+  }
+}
+
 STATIC
 VOID
 PcatPciRootBridgeParseBars (
@@ -75,6 +91,11 @@ PcatPciRootBridgeParseBars (
   UINT64                            Limit;
   PCI_ROOT_BRIDGE_APERTURE          *MemAperture;
 
+  // Disable address decoding for every device before OVMF starts sizing it
+  PcatPciRootBridgeDecodingDisable (
+    PCI_LIB_ADDRESS (Bus, Device, Function, PCI_COMMAND_OFFSET)
+  );
+
   for (Offset = BarOffsetBase; Offset < BarOffsetEnd; Offset += sizeof (UINT32)) {
     PcatPciRootBridgeBarExisted (
       PCI_LIB_ADDRESS (Bus, Device, Function, Offset),
-- 
2.7.4


_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel

Re: [edk2-devel] [PATCH v3 3/3] OvmfPkg/XenSupport: turn off address decoding before BAR sizing

Posted by Laszlo Ersek 6 years, 9 months ago

On 04/25/19 22:23, Igor Druzhinin wrote:
> On Xen, hvmloader firmware leaves address decoding enabled for
> enumerated PCI device before jumping into OVMF. OVMF seems to
> expect it to be disabled and tries to size PCI BARs in several places
> without disabling it which causes BAR64, for example, being
> incorrectly placed by QEMU.
> 
> Fix it by disabling PCI address decoding explicitly before the
> first attempt to size BARs on Xen.
> 
> Signed-off-by: Igor Druzhinin <igor.druzhinin@citrix.com>
> ---
> Changes in v3:
> - dropped unused arguments and rename PcatPciRootBridgeDecoding function
> - make mask application more clear as suggested
> ---
>  OvmfPkg/Library/PciHostBridgeLib/XenSupport.c | 21 +++++++++++++++++++++
>  1 file changed, 21 insertions(+)
> 
> diff --git a/OvmfPkg/Library/PciHostBridgeLib/XenSupport.c b/OvmfPkg/Library/PciHostBridgeLib/XenSupport.c
> index 76fca53..b41bd6b 100644
> --- a/OvmfPkg/Library/PciHostBridgeLib/XenSupport.c
> +++ b/OvmfPkg/Library/PciHostBridgeLib/XenSupport.c
> @@ -49,6 +49,22 @@ PcatPciRootBridgeBarExisted (
>    EnableInterrupts ();
>  }
>  
> +#define PCI_COMMAND_DECODE ((UINT16)(EFI_PCI_COMMAND_IO_SPACE | \
> +                                     EFI_PCI_COMMAND_MEMORY_SPACE))
> +STATIC
> +VOID
> +PcatPciRootBridgeDecodingDisable (
> +  IN  UINTN                          Address
> +  )
> +{
> +  UINT16                             Value;
> +
> +  Value = PciRead16 (Address);
> +  if (Value & PCI_COMMAND_DECODE) {
> +    PciWrite16 (Address, Value & ~(UINT32)PCI_COMMAND_DECODE);
> +  }
> +}
> +
>  STATIC
>  VOID
>  PcatPciRootBridgeParseBars (
> @@ -75,6 +91,11 @@ PcatPciRootBridgeParseBars (
>    UINT64                            Limit;
>    PCI_ROOT_BRIDGE_APERTURE          *MemAperture;
>  
> +  // Disable address decoding for every device before OVMF starts sizing it
> +  PcatPciRootBridgeDecodingDisable (
> +    PCI_LIB_ADDRESS (Bus, Device, Function, PCI_COMMAND_OFFSET)
> +  );
> +
>    for (Offset = BarOffsetBase; Offset < BarOffsetEnd; Offset += sizeof (UINT32)) {
>      PcatPciRootBridgeBarExisted (
>        PCI_LIB_ADDRESS (Bus, Device, Function, Offset),
> 

Acked-by: Laszlo Ersek <lersek@redhat.com>

Someone from the Xen community please ACK this too, and then we can push
the series.

Thanks,
Laszlo

-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.

View/Reply Online (#39658): https://edk2.groups.io/g/devel/message/39658
Mute This Topic: https://groups.io/mt/31346559/1787277
Group Owner: devel+owner@edk2.groups.io
Unsubscribe: https://edk2.groups.io/g/devel/unsub  [importer@patchew.org]
-=-=-=-=-=-=-=-=-=-=-=-

Re: [edk2-devel] [PATCH v3 3/3] OvmfPkg/XenSupport: turn off address decoding before BAR sizing

Posted by Anthony PERARD 6 years, 9 months ago

On Fri, Apr 26, 2019 at 08:15:07PM +0200, Laszlo Ersek wrote:
> On 04/25/19 22:23, Igor Druzhinin wrote:
> > On Xen, hvmloader firmware leaves address decoding enabled for
> > enumerated PCI device before jumping into OVMF. OVMF seems to
> > expect it to be disabled and tries to size PCI BARs in several places
> > without disabling it which causes BAR64, for example, being
> > incorrectly placed by QEMU.
> > 
> > Fix it by disabling PCI address decoding explicitly before the
> > first attempt to size BARs on Xen.
> > 
> > Signed-off-by: Igor Druzhinin <igor.druzhinin@citrix.com>
> > ---
> > Changes in v3:
> > - dropped unused arguments and rename PcatPciRootBridgeDecoding function
> > - make mask application more clear as suggested
> > ---
> >  OvmfPkg/Library/PciHostBridgeLib/XenSupport.c | 21 +++++++++++++++++++++
> >  1 file changed, 21 insertions(+)
> > 
> > diff --git a/OvmfPkg/Library/PciHostBridgeLib/XenSupport.c b/OvmfPkg/Library/PciHostBridgeLib/XenSupport.c
> > index 76fca53..b41bd6b 100644
> > --- a/OvmfPkg/Library/PciHostBridgeLib/XenSupport.c
> > +++ b/OvmfPkg/Library/PciHostBridgeLib/XenSupport.c
> > @@ -49,6 +49,22 @@ PcatPciRootBridgeBarExisted (
> >    EnableInterrupts ();
> >  }
> >  
> > +#define PCI_COMMAND_DECODE ((UINT16)(EFI_PCI_COMMAND_IO_SPACE | \
> > +                                     EFI_PCI_COMMAND_MEMORY_SPACE))
> > +STATIC
> > +VOID
> > +PcatPciRootBridgeDecodingDisable (
> > +  IN  UINTN                          Address
> > +  )
> > +{
> > +  UINT16                             Value;
> > +
> > +  Value = PciRead16 (Address);
> > +  if (Value & PCI_COMMAND_DECODE) {
> > +    PciWrite16 (Address, Value & ~(UINT32)PCI_COMMAND_DECODE);
> > +  }
> > +}
> > +
> >  STATIC
> >  VOID
> >  PcatPciRootBridgeParseBars (
> > @@ -75,6 +91,11 @@ PcatPciRootBridgeParseBars (
> >    UINT64                            Limit;
> >    PCI_ROOT_BRIDGE_APERTURE          *MemAperture;
> >  
> > +  // Disable address decoding for every device before OVMF starts sizing it
> > +  PcatPciRootBridgeDecodingDisable (
> > +    PCI_LIB_ADDRESS (Bus, Device, Function, PCI_COMMAND_OFFSET)
> > +  );
> > +
> >    for (Offset = BarOffsetBase; Offset < BarOffsetEnd; Offset += sizeof (UINT32)) {
> >      PcatPciRootBridgeBarExisted (
> >        PCI_LIB_ADDRESS (Bus, Device, Function, Offset),
> > 
> 
> Acked-by: Laszlo Ersek <lersek@redhat.com>
> 
> Someone from the Xen community please ACK this too, and then we can push
> the series.

Acked-by: Anthony PERARD <anthony.perard@citrix.com>

Thanks,

-- 
Anthony PERARD

-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.

View/Reply Online (#39861): https://edk2.groups.io/g/devel/message/39861
Mute This Topic: https://groups.io/mt/31346559/1787277
Group Owner: devel+owner@edk2.groups.io
Unsubscribe: https://edk2.groups.io/g/devel/unsub  [importer@patchew.org]
-=-=-=-=-=-=-=-=-=-=-=-

Re: [edk2-devel] [PATCH v3 3/3] OvmfPkg/XenSupport: turn off address decoding before BAR sizing

Posted by Laszlo Ersek 6 years, 9 months ago

On 04/30/19 18:35, Anthony PERARD wrote:
> On Fri, Apr 26, 2019 at 08:15:07PM +0200, Laszlo Ersek wrote:
>> On 04/25/19 22:23, Igor Druzhinin wrote:
>>> On Xen, hvmloader firmware leaves address decoding enabled for
>>> enumerated PCI device before jumping into OVMF. OVMF seems to
>>> expect it to be disabled and tries to size PCI BARs in several places
>>> without disabling it which causes BAR64, for example, being
>>> incorrectly placed by QEMU.
>>>
>>> Fix it by disabling PCI address decoding explicitly before the
>>> first attempt to size BARs on Xen.
>>>
>>> Signed-off-by: Igor Druzhinin <igor.druzhinin@citrix.com>
>>> ---
>>> Changes in v3:
>>> - dropped unused arguments and rename PcatPciRootBridgeDecoding function
>>> - make mask application more clear as suggested
>>> ---
>>>  OvmfPkg/Library/PciHostBridgeLib/XenSupport.c | 21 +++++++++++++++++++++
>>>  1 file changed, 21 insertions(+)
>>>
>>> diff --git a/OvmfPkg/Library/PciHostBridgeLib/XenSupport.c b/OvmfPkg/Library/PciHostBridgeLib/XenSupport.c
>>> index 76fca53..b41bd6b 100644
>>> --- a/OvmfPkg/Library/PciHostBridgeLib/XenSupport.c
>>> +++ b/OvmfPkg/Library/PciHostBridgeLib/XenSupport.c
>>> @@ -49,6 +49,22 @@ PcatPciRootBridgeBarExisted (
>>>    EnableInterrupts ();
>>>  }
>>>  
>>> +#define PCI_COMMAND_DECODE ((UINT16)(EFI_PCI_COMMAND_IO_SPACE | \
>>> +                                     EFI_PCI_COMMAND_MEMORY_SPACE))
>>> +STATIC
>>> +VOID
>>> +PcatPciRootBridgeDecodingDisable (
>>> +  IN  UINTN                          Address
>>> +  )
>>> +{
>>> +  UINT16                             Value;
>>> +
>>> +  Value = PciRead16 (Address);
>>> +  if (Value & PCI_COMMAND_DECODE) {
>>> +    PciWrite16 (Address, Value & ~(UINT32)PCI_COMMAND_DECODE);
>>> +  }
>>> +}
>>> +
>>>  STATIC
>>>  VOID
>>>  PcatPciRootBridgeParseBars (
>>> @@ -75,6 +91,11 @@ PcatPciRootBridgeParseBars (
>>>    UINT64                            Limit;
>>>    PCI_ROOT_BRIDGE_APERTURE          *MemAperture;
>>>  
>>> +  // Disable address decoding for every device before OVMF starts sizing it
>>> +  PcatPciRootBridgeDecodingDisable (
>>> +    PCI_LIB_ADDRESS (Bus, Device, Function, PCI_COMMAND_OFFSET)
>>> +  );
>>> +
>>>    for (Offset = BarOffsetBase; Offset < BarOffsetEnd; Offset += sizeof (UINT32)) {
>>>      PcatPciRootBridgeBarExisted (
>>>        PCI_LIB_ADDRESS (Bus, Device, Function, Offset),
>>>
>>
>> Acked-by: Laszlo Ersek <lersek@redhat.com>
>>
>> Someone from the Xen community please ACK this too, and then we can push
>> the series.
> 
> Acked-by: Anthony PERARD <anthony.perard@citrix.com>

Series pushed as commit range 9fb2ce2f465d..0c40c9c925ca.

Thanks
Laszlo

-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.

View/Reply Online (#39862): https://edk2.groups.io/g/devel/message/39862
Mute This Topic: https://groups.io/mt/31346559/1787277
Group Owner: devel+owner@edk2.groups.io
Unsubscribe: https://edk2.groups.io/g/devel/unsub  [importer@patchew.org]
-=-=-=-=-=-=-=-=-=-=-=-