Re: [PATCH v2] MdeModulePkg/Bus: Enable to use device address when programming BARs

["Ni, Ruiyu" <ruiyu.ni@intel.com>]

Roman,
Can you point to me the spec content which states the “Offset” instead of “Base + Offset” should be written to the BAR?
Does the policy apply to all PCI devices in a system, or certain PCI devices in a system?

Thanks/Ray

From: Roman Bacik <roman.bacik@broadcom.com>
Sent: Thursday, May 10, 2018 4:25 AM
To: edk2-devel@lists.01.org
Cc: Ni, Ruiyu <ruiyu.ni@intel.com>; Vladimir Olovyannikov <vladimir.olovyannikov@broadcom.com>
Subject: [edk2] [PATCH v2] MdeModulePkg/Bus: Enable to use device address when programming BARs

Some SoCs require to use device address when BARs are programmed:
https://bugzilla.tianocore.org/show_bug.cgi?id=948

Cc: Ruiyu Ni <ruiyu.ni@intel.com<mailto:ruiyu.ni@intel.com>>
Cc: Vladimir Olovyannikov <vladimir.olovyannikov@broadcom.com<mailto:vladimir.olovyannikov@broadcom.com>>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Roman Bacik <roman.bacik@broadcom.com<mailto:roman.bacik@broadcom.com>>
---
 MdeModulePkg/Bus/Pci/PciBusDxe/PciBusDxe.inf        | 1 +
 MdeModulePkg/Bus/Pci/PciBusDxe/PciResourceSupport.c | 8 +++++---
 MdeModulePkg/MdeModulePkg.dec                       | 3 +++
 MdeModulePkg/MdeModulePkg.dsc                       | 1 +
 4 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciBusDxe.inf b/MdeModulePkg/Bus/Pci/PciBusDxe/PciBusDxe.inf
index 97608bfcf245..1368e5068574 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciBusDxe.inf
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciBusDxe.inf
@@ -110,6 +110,7 @@
   gEfiMdeModulePkgTokenSpaceGuid.PcdAriSupport                  ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdMrIovSupport                ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdPciDisableBusEnumeration    ## SOMETIMES_CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdUseDeviceAddress        ## CONSUMES

 [UserExtensions.TianoCore."ExtraFiles"]
   PciBusDxeExtra.uni
diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciResourceSupport.c b/MdeModulePkg/Bus/Pci/PciBusDxe/PciResourceSupport.c
index 2f713fcee95e..a23bd1e258ef 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciResourceSupport.c
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciResourceSupport.c
@@ -1269,6 +1269,7 @@ ProgramBar (
   EFI_PCI_IO_PROTOCOL *PciIo;
   UINT64              Address;
   UINT32              Address32;
+  BOOLEAN             UseDeviceAddress;

   ASSERT (Node->Bar < PCI_MAX_BAR);

@@ -1282,8 +1283,9 @@ ProgramBar (

   Address = 0;
   PciIo   = &(Node->PciDev->PciIo);
+  UseDeviceAddress = FeaturePcdGet (PcdUseDeviceAddress);

-  Address = Base + Node->Offset;
+  Address = UseDeviceAddress? Node->Offset: Base + Node->Offset;

   //
   // Indicate pci bus driver has allocated
@@ -1308,7 +1310,7 @@ ProgramBar (
                  &Address
                  );

-    Node->PciDev->PciBar[Node->Bar].BaseAddress = Address;
+    Node->PciDev->PciBar[Node->Bar].BaseAddress = UseDeviceAddress? Base + Address: Address;

     break;

@@ -1335,7 +1337,7 @@ ProgramBar (
                  &Address32
                  );

-    Node->PciDev->PciBar[Node->Bar].BaseAddress = Address;
+    Node->PciDev->PciBar[Node->Bar].BaseAddress = UseDeviceAddress? Base + Address: Address;

     break;

diff --git a/MdeModulePkg/MdeModulePkg.dec b/MdeModulePkg/MdeModulePkg.dec
index cc397185f7b9..58425ee0d57f 100644
--- a/MdeModulePkg/MdeModulePkg.dec
+++ b/MdeModulePkg/MdeModulePkg.dec
@@ -1005,6 +1005,9 @@
   # @Prompt Enable UEFI Stack Guard.
   gEfiMdeModulePkgTokenSpaceGuid.PcdCpuStackGuard|FALSE|BOOLEAN|0x30001055

+  ## Indicates whether the device address should be used for BAR programming
+  gEfiMdeModulePkgTokenSpaceGuid.PcdUseDeviceAddress|FALSE|BOOLEAN|0x30001056
+
 [PcdsFixedAtBuild, PcdsPatchableInModule]
   ## Dynamic type PCD can be registered callback function for Pcd setting action.
   #  PcdMaxPeiPcdCallBackNumberPerPcdEntry indicates the maximum number of callback function
diff --git a/MdeModulePkg/MdeModulePkg.dsc b/MdeModulePkg/MdeModulePkg.dsc
index ec24a50c7d0a..39b397cb13d9 100644
--- a/MdeModulePkg/MdeModulePkg.dsc
+++ b/MdeModulePkg/MdeModulePkg.dsc
@@ -200,6 +200,7 @@
   gEfiMdeModulePkgTokenSpaceGuid.PcdMaxSizeNonPopulateCapsule|0x0
   gEfiMdeModulePkgTokenSpaceGuid.PcdMaxSizePopulateCapsule|0x0
   gEfiMdeModulePkgTokenSpaceGuid.PcdMaxPeiPerformanceLogEntries|28
+  gEfiMdeModulePkgTokenSpaceGuid.PcdUseDeviceAddress|FALSE

 [PcdsFixedAtBuild.IPF]
   gEfiMdePkgTokenSpaceGuid.PcdIoBlockBaseAddressForIpf|0x0ffffc000000
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