MdeModulePkg/Bus/Pci/NvmExpressPei/NvmExpressPeiS3.c

   1 /** @file
   2   The NvmExpressPei driver is used to manage non-volatile memory subsystem
   3   which follows NVM Express specification at PEI phase.
   4
   5   Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
   6
   7   SPDX-License-Identifier: BSD-2-Clause-Patent
   8
   9 **/
  10
  11 #include "NvmExpressPei.h"
  12
  13 #include <Guid/S3StorageDeviceInitList.h>
  14
  15 #include <Library/LockBoxLib.h>
  16
  17 /**
  18   Determine if a specific NVM Express controller can be skipped for S3 phase.
  19
  20   @param[in]  HcDevicePath          Device path of the controller.
  21   @param[in]  HcDevicePathLength    Length of the device path specified by
  22                                     HcDevicePath.
  23
  24   @retval    The number of ports that need to be enumerated.
  25
  26 **/
  27 BOOLEAN
  28 NvmeS3SkipThisController (
  29   IN  EFI_DEVICE_PATH_PROTOCOL    *HcDevicePath,
  30   IN  UINTN                       HcDevicePathLength
  31   )
  32 {
  33   EFI_STATUS                  Status;
  34   UINT8                       DummyData;
  35   UINTN                       S3InitDevicesLength;
  36   EFI_DEVICE_PATH_PROTOCOL    *S3InitDevices;
  37   EFI_DEVICE_PATH_PROTOCOL    *DevicePathInst;
  38   UINTN                       DevicePathInstLength;
  39   BOOLEAN                     EntireEnd;
  40   BOOLEAN                     Skip;
  41
  42   //
  43   // From the LockBox, get the list of device paths for devices need to be
  44   // initialized in S3.
  45   //
  46   S3InitDevices       = NULL;
  47   S3InitDevicesLength = sizeof (DummyData);
  48   EntireEnd           = FALSE;
  49   Skip                = TRUE;
  50   Status = RestoreLockBox (&gS3StorageDeviceInitListGuid, &DummyData, &S3InitDevicesLength);
  51   if (Status != EFI_BUFFER_TOO_SMALL) {
  52     return Skip;
  53   } else {
  54     S3InitDevices = AllocatePool (S3InitDevicesLength);
  55     if (S3InitDevices == NULL) {
  56       return Skip;
  57     }
  58
  59     Status = RestoreLockBox (&gS3StorageDeviceInitListGuid, S3InitDevices, &S3InitDevicesLength);
  60     if (EFI_ERROR (Status)) {
  61       return Skip;
  62     }
  63   }
  64
  65   if (S3InitDevices == NULL) {
  66     return Skip;
  67   }
  68
  69   //
  70   // Only need to initialize the controllers that exist in the device list.
  71   //
  72   do {
  73     //
  74     // Fetch the size of current device path instance.
  75     //
  76     Status = GetDevicePathInstanceSize (
  77                S3InitDevices,
  78                &DevicePathInstLength,
  79                &EntireEnd
  80                );
  81     if (EFI_ERROR (Status)) {
  82       break;
  83     }
  84
  85     DevicePathInst = S3InitDevices;
  86     S3InitDevices  = (EFI_DEVICE_PATH_PROTOCOL *)((UINTN) S3InitDevices + DevicePathInstLength);
  87
  88     if (HcDevicePathLength >= DevicePathInstLength) {
  89       continue;
  90     }
  91
  92     //
  93     // Compare the device paths to determine if the device is managed by this
  94     // controller.
  95     //
  96     if (CompareMem (
  97           DevicePathInst,
  98           HcDevicePath,
  99           HcDevicePathLength - sizeof (EFI_DEVICE_PATH_PROTOCOL)
 100           ) == 0) {
 101       Skip = FALSE;
 102       break;
 103     }
 104   } while (!EntireEnd);
 105
 106   return Skip;
 107 }