slimbootloader/BootloaderCommonPkg/Library/ShellLib/CmdPci.c

/** @file
  Shell command `pci` to display PCI devices.

  Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
  SPDX-License-Identifier: BSD-2-Clause-Patent

**/

#include <Library/ShellLib.h>
#include <IndustryStandard/Pci.h>
#include <Library/PciExpressLib.h>
#include "CmdPciUtil.h"

/**
  Display PCI devices.

  @param[in]  Shell        shell instance
  @param[in]  Argc         number of command line arguments
  @param[in]  Argv         command line arguments

  @retval EFI_SUCCESS

**/
STATIC
EFI_STATUS
EFIAPI
ShellCommandPciFunc (
  IN SHELL  *Shell,
  IN UINTN   Argc,
  IN CHAR16 *Argv[]
  );

CONST SHELL_COMMAND ShellCommandPci = {
  L"pci",
  L"Display PCI devices",
  &ShellCommandPciFunc
};

/**
  Display PCI devices.

  @param[in]  Shell        shell instance
  @param[in]  Argc         number of command line arguments
  @param[in]  Argv         command line arguments

  @retval EFI_SUCCESS

**/
STATIC
EFI_STATUS
EFIAPI
ShellCommandPciFunc (
  IN SHELL  *Shell,
  IN UINTN   Argc,
  IN CHAR16 *Argv[]
  )
{
  UINTN                                   Bus, Dev, Func, Index;
  volatile PCI_DEVICE_INDEPENDENT_REGION *PciDev;
  PCI_CLASS_STRINGS                       ClassStrings;
  UINT32                                  ClassCode;
  BOOLEAN                                 Verbose;

  Verbose = FALSE;

  // Check flags
  for (Index = 0; Index < Argc; Index++) {
    if (StrCmp (Argv[Index], L"-h") == 0) {
      goto usage;
    }
    if (StrCmp (Argv[Index], L"-v") == 0) {
      Verbose = TRUE;
    }
  }

  // Scan PCI config space and report present BDFs
  for (Bus = 0; Bus <= PCI_MAX_BUS; Bus++) {
    for (Dev = 0; Dev <= PCI_MAX_DEVICE; Dev++) {
      for (Func = 0; Func <= PCI_MAX_FUNC; Func++) {
        // Calculate MMIO address of PCI device configuration space
        PciDev = (volatile VOID *) (UINTN) (PcdGet64 (PcdPciExpressBaseAddress)
                                            + PCI_EXPRESS_LIB_ADDRESS (Bus, Dev, Func, 0));

        // Check Vendor ID to see if this device is present
        if (PciDev->VendorId == 0xffff) {
          if (Func == 0) {
            break;
          } else {
            continue;
          }
        }

        // Get string descriptions of the class/subclass/interface
        ClassCode = ( (PciDev->ClassCode[2] << 16 )
                      | (PciDev->ClassCode[1] << 8  )
                      | (PciDev->ClassCode[0])
                      );
        PciGetClassStrings (ClassCode, &ClassStrings);

        // Report bus/device/function
        ShellPrint (L"%02x:%02x.%x %04x:%04x %s\n", Bus, Dev, Func,
                    PciDev->VendorId,
                    PciDev->DeviceId,
                    ClassStrings.BaseClass);

        // Report extra device information if the verbose flag was given
        if (Verbose) {
          ShellPrint (L"Config Space Address: %p\n", PciDev);
          if (StrLen (ClassStrings.SubClass)) {
            ShellPrint (L"SubClass: %s", ClassStrings.SubClass);
            if (StrLen (ClassStrings.PIFClass)) {
              ShellPrint (L" (%s)", ClassStrings.PIFClass);
            }
          }
          ShellPrint (L"\n\n");
        }
      }
    }
  }

  return EFI_SUCCESS;

usage:
  ShellPrint (L"Usage: %s [-v]\n", Argv[0]);
  ShellPrint (L"\n"
              L"Flags:\n"
              L"  -v     Verbose\n");
  return EFI_ABORTED;
}