Re: [PATCH 1/2] MdeModulePkg/PciBus: Revert "disable all BME when entering RT"

["Yao, Jiewen" <jiewen.yao@intel.com>]

Reviewed-by: Jiewen.yao@intel.com

> -----Original Message-----
> From: Ni, Ruiyu
> Sent: Monday, November 20, 2017 11:06 AM
> To: edk2-devel@lists.01.org
> Cc: Ni, Ruiyu <ruiyu.ni@intel.com>; Michael Turner
> <michael.turner@microsoft.com>; Kinney, Michael D
> <michael.d.kinney@intel.com>; Yao, Jiewen <jiewen.yao@intel.com>
> Subject: [PATCH 1/2] MdeModulePkg/PciBus: Revert "disable all BME when
> entering RT"
> 
> This reverts commit 050763db0730a0bb46235cec87e3716632dc532c.
>   "MdeModulePkg/PciBus: Disable BME of all devices when entering RT"
> 
> We met some compatibility issues when doing Windows S4 resume.
> Reverting the BME disabling patches to fix the S4 resume issue.
> 
> Signed-off-by: Ruiyu Ni <Ruiyu.ni@intel.com>
> Signed-off-by: Michael Turner <michael.turner@microsoft.com>
> Cc: Michael D Kinney <Michael.d.kinney@intel.com>
> Cc: Jiewen Yao <jiewen.yao@intel.com>
> ---
>  MdeModulePkg/Bus/Pci/PciBusDxe/PciBus.h           |  2 -
>  MdeModulePkg/Bus/Pci/PciBusDxe/PciBusDxe.inf      |  3 -
>  MdeModulePkg/Bus/Pci/PciBusDxe/PciDeviceSupport.c | 86 -----------------------
>  3 files changed, 91 deletions(-)
> 
> diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciBus.h
> b/MdeModulePkg/Bus/Pci/PciBusDxe/PciBus.h
> index 79b5b71082..55eb3a5a80 100644
> --- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciBus.h
> +++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciBus.h
> @@ -18,8 +18,6 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND,
> EITHER EXPRESS OR IMPLIED.
> 
>  #include <PiDxe.h>
> 
> -#include <Guid/EventGroup.h>
> -
>  #include <Protocol/LoadedImage.h>
>  #include <Protocol/PciHostBridgeResourceAllocation.h>
>  #include <Protocol/PciIo.h>
> diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciBusDxe.inf
> b/MdeModulePkg/Bus/Pci/PciBusDxe/PciBusDxe.inf
> index d5b8fab3ca..97608bfcf2 100644
> --- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciBusDxe.inf
> +++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciBusDxe.inf
> @@ -80,9 +80,6 @@ [LibraryClasses]
>    DebugLib
>    PeCoffLib
> 
> -[Guids]
> -  gEfiEventExitBootServicesGuid                   ##
> SOMETIMES_CONSUMES ## Event
> -
>  [Protocols]
>    gEfiPciHotPlugRequestProtocolGuid               ##
> SOMETIMES_PRODUCES
>    gEfiPciIoProtocolGuid                           ## BY_START
> diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciDeviceSupport.c
> b/MdeModulePkg/Bus/Pci/PciBusDxe/PciDeviceSupport.c
> index 004f2a3b5b..97bb971a59 100644
> --- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciDeviceSupport.c
> +++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciDeviceSupport.c
> @@ -20,72 +20,6 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY
> KIND, EITHER EXPRESS OR IMPLIED.
>  //
>  LIST_ENTRY  mPciDevicePool;
> 
> -/**
> - Disable Bus Master Enable bit in all devices in the list.
> -
> - @param Devices  A device list.
> -**/
> -VOID
> -DisableBmeOnTree (
> -  IN LIST_ENTRY      *Devices
> -  )
> -{
> -  LIST_ENTRY      *Link;
> -  PCI_IO_DEVICE   *PciIoDevice;
> -  UINT16           Command;
> -
> -  for ( Link = GetFirstNode (Devices)
> -      ; !IsNull (Devices, Link)
> -      ; Link = GetNextNode (Devices, Link)
> -      ) {
> -    PciIoDevice = PCI_IO_DEVICE_FROM_LINK (Link);
> -    //
> -    // Turn off all children's Bus Master, if any
> -    //
> -    DisableBmeOnTree (&PciIoDevice->ChildList);
> -
> -    //
> -    // If this is a device that supports BME, disable BME on this device.
> -    //
> -    if ((PciIoDevice->Supports & EFI_PCI_IO_ATTRIBUTE_BUS_MASTER) != 0) {
> -      PCI_READ_COMMAND_REGISTER(PciIoDevice, &Command);
> -      if ((Command & EFI_PCI_COMMAND_BUS_MASTER) != 0) {
> -        Command &= ~EFI_PCI_COMMAND_BUS_MASTER;
> -        PCI_SET_COMMAND_REGISTER (PciIoDevice, Command);
> -        DEBUG ((
> -          DEBUG_INFO,"  %02x   %02x      %02x         %04x\n",
> -          PciIoDevice->BusNumber, PciIoDevice->DeviceNumber,
> PciIoDevice->FunctionNumber,
> -          Command
> -          ));
> -      }
> -    }
> -  }
> -}
> -
> -/**
> -  Exit Boot Services Event notification handler.
> -
> -  Disable Bus Master on any that were enabled during BDS.
> -
> -  @param[in]  Event     Event whose notification function is being invoked.
> -  @param[in]  Context   Pointer to the notification function's context.
> -
> -**/
> -VOID
> -EFIAPI
> -OnExitBootServices (
> -  IN      EFI_EVENT                 Event,
> -  IN      VOID                      *Context
> -  )
> -{
> -  DEBUG ((
> -    DEBUG_INFO,
> -    "PciBus: Disable Bus Master of all devices...\n"
> -    "  Bus# Device# Function#  NewCommand\n"
> -    ));
> -  DisableBmeOnTree(&mPciDevicePool);
> -}
> -
>  /**
>    Initialize the PCI devices pool.
> 
> @@ -95,27 +29,7 @@ InitializePciDevicePool (
>    VOID
>    )
>  {
> -  EFI_EVENT   ExitBootServicesEvent;
> -  EFI_STATUS  Status;
> -
>    InitializeListHead (&mPciDevicePool);
> -
> -  //
> -  // DisableBME on ExitBootServices should be synchonized with any IOMMU
> ExitBootServices routine.
> -  // DisableBME should be run before the IOMMU protections are disabled.
> -  // One way to do this is to ensure that the IOMMU ExitBootServices callback
> runs at TPL_CALLBACK.
> -  //
> -  Status = gBS->CreateEventEx (
> -                  EVT_NOTIFY_SIGNAL,
> -                  TPL_NOTIFY,
> -                  OnExitBootServices,
> -                  NULL,
> -                  &gEfiEventExitBootServicesGuid,
> -                  &ExitBootServicesEvent
> -                  );
> -  if (EFI_ERROR (Status)) {
> -    DEBUG ((DEBUG_ERROR, "PciBus: Unable to hook ExitBootServices event
> - %r\n", Status));
> -  }
>  }
> 
>  /**
> --
> 2.15.0.gvfs.1.preview.4