[edk2-staging/UEFI_PCI_ENHANCE-2 PATCH 08/12] PciBusDxe: New PCI Express feature AtomicOp

["Javeed, Ashraf" <ashraf.javeed@intel.com>]

BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=2499

This code change handles two PCI Express features related to AtomicOp,
in compliance with the PCI Express Base SPecification 5:
(1) configuring PCI function as an AtomicOp Requester
(2) Enabling of Port Egress blocking depending on AtomicOp Routing
    Capability

These is programmed based on the following criteria:-
For a PCI Bridge device:
 - enables as AtomicOp Requester solely based on platform provided device
   policy
 - enabling of Port Egress blocking is based on platform device policy;
   only if its device capability register's AtomicOp Routing bit is 1

For an PCI EndPoint (EP) device:
 - if the platform's device policy wants to enable the AtomicOp Requester
   function for this device, than this device is enabled if all its bridge
   devices have the AtomicOp Routing capability bit set
 - Enabling of Port Egress disable is not applicable to PCI EP device

For an PCI RCiEP device:
 - the AtomicOp Requester functionality is enabled solely based on the
   device policy provided by platform
 - similar to PCI EP device, the enabling of port Egress blocking is not
   applicable

Signed-off-by: Ashraf Javeed <ashraf.javeed@intel.com>
Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao A Wu <hao.a.wu@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
---
 MdeModulePkg/Bus/Pci/PciBusDxe/PciBus.h             |   1 +
 MdeModulePkg/Bus/Pci/PciBusDxe/PciExpressFeatures.c | 161 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 MdeModulePkg/Bus/Pci/PciBusDxe/PciExpressFeatures.h |  35 +++++++++++++++++++++++++++++++++++
 MdeModulePkg/Bus/Pci/PciBusDxe/PciFeatureSupport.c  |  23 ++++++++++++++++++++++-
 MdeModulePkg/Bus/Pci/PciBusDxe/PciFeatureSupport.h  |   5 +++++
 MdeModulePkg/Bus/Pci/PciBusDxe/PciPlatformSupport.c |  23 +++++++++++++++++++++++
 6 files changed, 247 insertions(+), 1 deletion(-)

diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciBus.h b/MdeModulePkg/Bus/Pci/PciBusDxe/PciBus.h
index 9b03c12..57ef1b2 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciBus.h
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciBus.h
@@ -295,6 +295,7 @@ struct _PCI_IO_DEVICE {
   PCI_FEATURE_POLICY                        SetupRO;
   PCI_FEATURE_POLICY                        SetupNS;
   PCI_FEATURE_POLICY                        SetupCTO;
+  EFI_PCI_EXPRESS_ATOMIC_OP                 SetupAtomicOp;
 };
 
 #define PCI_IO_DEVICE_FROM_PCI_IO_THIS(a) \
diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciExpressFeatures.c b/MdeModulePkg/Bus/Pci/PciBusDxe/PciExpressFeatures.c
index f3f4d39..5c76ba4 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciExpressFeatures.c
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciExpressFeatures.c
@@ -908,3 +908,164 @@ ProgramCompletionTimeout (
   return Status;
 }
 
+/**
+  Routine to setup the AtomicOp Requester in the PCI device, verifies the routing
+  support in the bridge devices, to be complaint as per the PCI Base specification.
+
+  @param PciDevice                      A pointer to the PCI_IO_DEVICE.
+  @param PciExFeatureConfiguration      pointer to common configuration table to
+                                        initialize the PCI Express feature
+
+  @retval EFI_SUCCESS                   bridge device routing capability is successful.
+          EFI_INVALID_PARAMETER         input parameter is NULL
+**/
+EFI_STATUS
+SetupAtomicOpRoutingSupport (
+  IN PCI_IO_DEVICE                              *PciDevice,
+  IN PCI_EXPRESS_FEATURES_CONFIGURATION_TABLE   *PciExFeatureConfiguration
+  )
+{
+  //
+  // to enable the AtomicOp Requester in the PCI EP device; its Root Port (bridge),
+  // and its PCIe switch upstream & downstream ports (if present) needs to support
+  // the AtomicOp Routing capability.
+  //
+  if (IS_PCI_BRIDGE (&PciDevice->Pci)) {
+    if (!PciDevice->PciExpressCapabilityStructure.DeviceCapability2.Bits.AtomicOpRouting) {
+      //
+      // since the AtomicOp Routing support flag is initialized as TRUE, negate
+      // in case if any of the PCI Bridge device in the PCI tree does not support
+      // the AtomicOp Routing capability
+      //
+      if (PciExFeatureConfiguration == NULL) {
+        return EFI_INVALID_PARAMETER;
+      }
+      PciExFeatureConfiguration->AtomicOpRoutingSupported = FALSE;
+    }
+  }
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Overrides the PCI Device Control 2 register AtomicOp Requester enable field; if
+  the hardware value is different than the intended value.
+
+  @param  PciDevice             A pointer to the PCI_IO_DEVICE instance.
+
+  @retval EFI_SUCCESS           The data was read from or written to the PCI device.
+  @retval EFI_UNSUPPORTED       The address range specified by Offset, Width, and Count is not
+                                valid for the PCI configuration header of the PCI controller.
+  @retval EFI_INVALID_PARAMETER Buffer is NULL or Width is invalid.
+
+**/
+EFI_STATUS
+ProgramAtomicOp (
+  IN PCI_IO_DEVICE                            *PciDevice,
+  IN PCI_EXPRESS_FEATURES_CONFIGURATION_TABLE *PciExFeatureConfiguration
+  )
+{
+  PCI_REG_PCIE_DEVICE_CONTROL2  PcieDev;
+  UINT32                        Offset;
+  EFI_STATUS                    Status;
+  EFI_TPL                       OldTpl;
+
+  PcieDev.Uint16 = 0;
+  Offset = PciDevice->PciExpressCapabilityOffset +
+               OFFSET_OF (PCI_CAPABILITY_PCIEXP, DeviceControl2);
+  Status = PciDevice->PciIo.Pci.Read (
+                                  &PciDevice->PciIo,
+                                  EfiPciIoWidthUint16,
+                                  Offset,
+                                  1,
+                                  &PcieDev.Uint16
+                                  );
+  ASSERT (Status == EFI_SUCCESS);
+
+  if (PciDevice->SetupAtomicOp.Override) {
+    //
+    // override AtomicOp requester device control bit of the device based on the
+    // platform request
+    //
+    if (IS_PCI_BRIDGE (&PciDevice->Pci)) {
+      //
+      // for a bridge device as AtomicOp Requester function; only platform override
+      // request is used to set the device control register
+      //
+      if (PcieDev.Bits.AtomicOpRequester != PciDevice->SetupAtomicOp.Enable_AtomicOpRequester) {
+        PcieDev.Bits.AtomicOpRequester = PciDevice->SetupAtomicOp.Enable_AtomicOpRequester;
+      }
+      //
+      // if platform also request its AtomicOp Egress blocking to be enabled; set
+      // only if its device capability's AtomicOpRouting bit is 1.
+      // applicable to only the bridge devices
+      //
+      if (PciDevice->SetupAtomicOp.Enable_AtomicOpEgressBlocking) {
+        if (PciDevice->PciExpressCapabilityStructure.DeviceCapability2.Bits.AtomicOpRouting) {
+          PcieDev.Bits.AtomicOpEgressBlocking = 1;
+        }
+      }
+    } else {
+      //
+      // in the case of non-bridge device
+      //
+      if (PciExFeatureConfiguration) {
+        //
+        // for a device as AtomicOp Requester function; its bridge devices should
+        // support the AtomicOp Routing capability to enable the device's as a
+        // requester function
+        //
+        if (PciExFeatureConfiguration->AtomicOpRoutingSupported) {
+          if (PcieDev.Bits.AtomicOpRequester != PciDevice->SetupAtomicOp.Enable_AtomicOpRequester) {
+            PcieDev.Bits.AtomicOpRequester = PciDevice->SetupAtomicOp.Enable_AtomicOpRequester;
+          }
+        }
+      } else {
+        //
+        // for the RCiEP device or the bridge device without any child, setup AtomicOp
+        // Requester as per platform's device policy
+        //
+        if (PcieDev.Bits.AtomicOpRequester != PciDevice->SetupAtomicOp.Enable_AtomicOpRequester) {
+          PcieDev.Bits.AtomicOpRequester = PciDevice->SetupAtomicOp.Enable_AtomicOpRequester;
+        }
+      }
+      //
+      // the enabling of AtomicOp Egress Blocking is not applicable to a non-bridge
+      // device
+      //
+    }
+    DEBUG ((
+      DEBUG_INFO,
+      "AtomicOp=%d,",
+      PcieDev.Bits.AtomicOpRequester
+      ));
+
+    //
+    // Raise TPL to high level to disable timer interrupt while the write operation completes
+    //
+    OldTpl = gBS->RaiseTPL (TPL_HIGH_LEVEL);
+
+    Status = PciDevice->PciIo.Pci.Write (
+                                    &PciDevice->PciIo,
+                                    EfiPciIoWidthUint16,
+                                    Offset,
+                                    1,
+                                    &PcieDev.Uint16
+                                    );
+    //
+    // Restore TPL to its original level
+    //
+    gBS->RestoreTPL (OldTpl);
+
+    if (!EFI_ERROR(Status)) {
+      PciDevice->PciExpressCapabilityStructure.DeviceControl2.Uint16 = PcieDev.Uint16;
+    } else {
+      ReportPciWriteError (PciDevice->BusNumber, PciDevice->DeviceNumber, PciDevice->FunctionNumber, Offset);
+    }
+  } else {
+    DEBUG (( DEBUG_INFO, "No AtomicOp,"));
+  }
+
+  return Status;
+}
+
diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciExpressFeatures.h b/MdeModulePkg/Bus/Pci/PciBusDxe/PciExpressFeatures.h
index 2ee7d4d..1e287fc 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciExpressFeatures.h
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciExpressFeatures.h
@@ -168,4 +168,39 @@ ProgramCompletionTimeout (
   IN VOID                   *PciExFeatureConfiguration
   );
 
+/**
+  Routine to setup the AtomicOp Requester in the PCI device, verifies the routing
+  support in the bridge devices, to be complaint as per the PCI Base specification.
+
+  @param PciDevice                      A pointer to the PCI_IO_DEVICE.
+  @param PciExFeatureConfiguration      pointer to common configuration table to
+                                        initialize the PCI Express feature
+
+  @retval EFI_SUCCESS                   bridge device routing capability is successful.
+          EFI_INVALID_PARAMETER         input parameter is NULL
+**/
+EFI_STATUS
+SetupAtomicOpRoutingSupport (
+  IN PCI_IO_DEVICE                              *PciDevice,
+  IN PCI_EXPRESS_FEATURES_CONFIGURATION_TABLE   *PciExFeatureConfiguration
+  );
+
+/**
+  Overrides the PCI Device Control 2 register AtomicOp Requester enable field; if
+  the hardware value is different than the intended value.
+
+  @param  PciDevice             A pointer to the PCI_IO_DEVICE instance.
+
+  @retval EFI_SUCCESS           The data was read from or written to the PCI device.
+  @retval EFI_UNSUPPORTED       The address range specified by Offset, Width, and Count is not
+                                valid for the PCI configuration header of the PCI controller.
+  @retval EFI_INVALID_PARAMETER Buffer is NULL or Width is invalid.
+
+**/
+EFI_STATUS
+ProgramAtomicOp (
+  IN PCI_IO_DEVICE          *PciDevice,
+  IN VOID                   *PciExFeatureConfiguration
+  );
+
 #endif
diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciFeatureSupport.c b/MdeModulePkg/Bus/Pci/PciBusDxe/PciFeatureSupport.c
index d4459f3..9d624a0 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciFeatureSupport.c
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciFeatureSupport.c
@@ -62,7 +62,7 @@ EFI_PCI_EXPRESS_PLATFORM_POLICY             mPciExpressPlatformPolicy = {
     //
     // support for PCI Express feature - Atomic Op
     //
-    FALSE,
+    TRUE,
     //
     // support for PCI Express feature - LTR
     //
@@ -125,6 +125,12 @@ PCI_EXPRESS_FEATURE_INITIALIZATION_POINT  mPciExpressFeatureInitializationList[]
   },
   {
     PciExpressFeatureProgramPhase,        PciExpressCto,        ProgramCompletionTimeout
+  },
+  {
+    PciExpressFeatureSetupPhase,          PciExpressAtomicOp,   SetupAtomicOpRoutingSupport
+  },
+  {
+    PciExpressFeatureProgramPhase,        PciExpressAtomicOp,   ProgramAtomicOp
   }
 };
 
@@ -297,6 +303,16 @@ IsPciExpressFeatureExtendedSetupRequired (
         && PciExpressPolicy[mPciExpressFeatureInitializationList[idx].PciExpressFeatureId] == TRUE
     ) {
       return TRUE;
+    } else if (
+        //
+        // the PCI Express feature does not require extended setup phase but it
+        // does require global flag to track the AtomicOpRouting caoability to
+        // be tracked for all its bridge devices
+        //
+        idx == PciExpressAtomicOp
+        && PciExpressPolicy[idx] == TRUE
+        ) {
+      return TRUE;
     }
   }
 
@@ -637,6 +653,11 @@ CreatePciRootBridgeDeviceNode (
     // the devices in the PCI tree
     //
     PciConfigTable->Lock_Max_Read_Request_Size  = FALSE;
+    //
+    // start by assuming the AtomicOp Routing capability is supported in the PCI
+    // tree
+    //
+    PciConfigTable->AtomicOpRoutingSupported    = TRUE;
   }
 
   RootBridgeNode->PciExFeaturesConfigurationTable  = PciConfigTable;
diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciFeatureSupport.h b/MdeModulePkg/Bus/Pci/PciBusDxe/PciFeatureSupport.h
index a1fc39c..2bd565e 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciFeatureSupport.h
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciFeatureSupport.h
@@ -80,6 +80,11 @@ struct _PCI_EXPRESS_FEATURES_CONFIGURATION_TABLE {
   // lock the Max_Read_Request_Size for the entire PCI tree of a root port
   //
   BOOLEAN                                   Lock_Max_Read_Request_Size;
+  //
+  // to record the AtomicOp Routing capability of the PCI Heirarchy to enable
+  // the AtomicOp of the EP device
+  //
+  BOOLEAN                                   AtomicOpRoutingSupported;
 };
 
 //
diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciPlatformSupport.c b/MdeModulePkg/Bus/Pci/PciBusDxe/PciPlatformSupport.c
index 1afea19..2707976 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciPlatformSupport.c
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciPlatformSupport.c
@@ -334,6 +334,8 @@ SetupDefaultPciExpressDevicePolicy (
 
   PciDevice->SetupCTO.Override = 0;
 
+  PciDevice->SetupAtomicOp.Override = 0;
+
 }
 
 /**
@@ -450,6 +452,14 @@ GetPciExpressDevicePolicy (
       PciDevice->SetupCTO.Override = 0;
     }
 
+    //
+    // set the device-specific policy for AtomicOp
+    //
+    if (mPciExpressPlatformPolicy.AtomicOp) {
+      PciDevice->SetupAtomicOp = PciExpressDevicePolicy.DeviceCtl2AtomicOp;
+    } else {
+      PciDevice->SetupAtomicOp.Override = 0;
+    }
 
     DEBUG ((
       DEBUG_INFO,
@@ -692,6 +702,19 @@ PciExpressPlatformNotifyDeviceState (
     PciExDeviceConfiguration.CTOsupport = EFI_PCI_EXPRESS_NOT_APPLICABLE;
   }
 
+  //
+  // get the device-specific state for the PCIe AtomicOp feature
+  //
+  if (mPciExpressPlatformPolicy.AtomicOp) {
+    PciExDeviceConfiguration.DeviceCtl2AtomicOp.Enable_AtomicOpRequester
+    = (UINT8)PciDevice->PciExpressCapabilityStructure.DeviceControl2.Bits.AtomicOpRequester;
+    PciExDeviceConfiguration.DeviceCtl2AtomicOp.Enable_AtomicOpEgressBlocking
+    = (UINT8)PciDevice->PciExpressCapabilityStructure.DeviceControl2.Bits.AtomicOpEgressBlocking;
+  } else {
+    PciExDeviceConfiguration.DeviceCtl2AtomicOp.Override = 0;
+    PciExDeviceConfiguration.DeviceCtl2AtomicOp.Enable_AtomicOpRequester = 0;
+    PciExDeviceConfiguration.DeviceCtl2AtomicOp.Enable_AtomicOpEgressBlocking = 0;
+  }
 
   if (mPciExPlatformProtocol != NULL) {
     return mPciExPlatformProtocol->NotifyDeviceState (
-- 
2.21.0.windows.1