From cb8349f01ae05cce46213fc98308ee524adf257b Mon Sep 17 00:00:00 2001
From: Min Xu <min.m.xu@intel.com>
Date: Thu, 24 Feb 2022 21:50:33 +0800
Subject: [PATCH] MdeModulePkg: Update PciEnumeratorSupport to ignore OptionRom
 if needed

RFC: https://bugzilla.tianocore.org/show_bug.cgi?id=3429

Function of UpdatePciInfo() in PciEnumeratorSupport.c is used to update
the bar information for those incompatible PCI device. It is the right
place to check if the OptionRom need to be ignored.

According to "Table 20. ACPI 2.0 & 3.0 QWORD Address Space Descriptor
Usage" in PI Spec 1.7, Type-specific flags can be set to 0 when Address
Translation Offset == 6 to skip device option ROM (do not probe option
rom BAR).

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Hao A Wu <hao.a.wu@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Erdem Aktas <erdemaktas@google.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Signed-off-by: Min Xu <min.m.xu@intel.com>
---
 .../Bus/Pci/PciBusDxe/PciEnumeratorSupport.c  | 23 +++++++++++++++----
 .../Bus/Pci/PciBusDxe/PciEnumeratorSupport.h  |  4 +++-
 2 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.c b/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.c
index 9251388bc2..509f828b62 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.c
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.c
@@ -220,8 +220,10 @@ PciSearchDevice (
   )
 {
   PCI_IO_DEVICE  *PciIoDevice;
+  BOOLEAN        IgnoreOptionRom;
 
-  PciIoDevice = NULL;
+  PciIoDevice     = NULL;
+  IgnoreOptionRom = FALSE;
 
   DEBUG ((
     DEBUG_INFO,
@@ -285,7 +287,7 @@ PciSearchDevice (
   //
   // Update the bar information for this PCI device so as to support some specific device
   //
-  UpdatePciInfo (PciIoDevice);
+  UpdatePciInfo (PciIoDevice, &IgnoreOptionRom);
 
   if (PciIoDevice->DevicePath == NULL) {
     return EFI_OUT_OF_RESOURCES;
@@ -295,7 +297,7 @@ PciSearchDevice (
   // Detect this function has option rom
   //
   if (gFullEnumeration) {
-    if (!IS_CARDBUS_BRIDGE (Pci)) {
+    if (!IS_CARDBUS_BRIDGE (Pci) && !IgnoreOptionRom) {
       GetOpRomInfo (PciIoDevice);
     }
 
@@ -1310,6 +1312,7 @@ DetermineDeviceAttribute (
 
   @param PciIoDevice      Input Pci device instance. Output Pci device instance with updated
                           Bar information.
+  @param IgnoreOptionRom  Output If the option rom of incompatible device need to be ignored.
 
   @retval EFI_SUCCESS     Successfully updated bar information.
   @retval EFI_UNSUPPORTED Given PCI device doesn't belong to incompatible PCI device list.
@@ -1317,7 +1320,8 @@ DetermineDeviceAttribute (
 **/
 EFI_STATUS
 UpdatePciInfo (
-  IN OUT PCI_IO_DEVICE  *PciIoDevice
+  IN OUT PCI_IO_DEVICE  *PciIoDevice,
+  OUT BOOLEAN           *IgnoreOptionRom
   )
 {
   EFI_STATUS                         Status;
@@ -1374,6 +1378,17 @@ UpdatePciInfo (
       break;
     }
 
+    //
+    // According to "Table 20. ACPI 2.0 & 3.0 QWORD Address Space Descriptor Usage"
+    // in PI Spec 1.7, Type-specific flags can be set to 0 when Address Translation
+    // Offset == 6 to skip device option ROM (do not probe option rom BAR).
+    //
+    if (((Ptr->AddrTranslationOffset == PCI_MAX_BAR) && (Ptr->SpecificFlag == 0))) {
+      *IgnoreOptionRom = TRUE;
+      Ptr++;
+      continue;
+    }
+
     for (BarIndex = 0; BarIndex < PCI_MAX_BAR; BarIndex++) {
       if ((Ptr->AddrTranslationOffset != MAX_UINT64) &&
           (Ptr->AddrTranslationOffset != MAX_UINT8) &&
diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.h b/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.h
index 0ded4bea4f..7daa6e020d 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.h
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.h
@@ -262,6 +262,7 @@ DetermineDeviceAttribute (
 
   @param PciIoDevice      Input Pci device instance. Output Pci device instance with updated
                           Bar information.
+  @param IgnoreOptionRom  Output If the option rom of incompatible device need to be ignored.
 
   @retval EFI_SUCCESS     Successfully updated bar information.
   @retval EFI_UNSUPPORTED Given PCI device doesn't belong to incompatible PCI device list.
@@ -269,7 +270,8 @@ DetermineDeviceAttribute (
 **/
 EFI_STATUS
 UpdatePciInfo (
-  IN OUT PCI_IO_DEVICE  *PciIoDevice
+  IN OUT PCI_IO_DEVICE  *PciIoDevice,
+  OUT BOOLEAN           *IgnoreOptionRom
   );
 
 /**
-- 
2.39.2