/** @file
*
*  Copyright (c) 2018, ARM Limited. All rights reserved.
*
*  SPDX-License-Identifier: BSD-2-Clause-Patent
*
**/

#include <Library/DebugLib.h>
#include <Library/HobLib.h>
#include <Library/PeimEntryPoint.h>
#include <Library/PeiServicesLib.h>
#include <libfdt.h>
#include <Ppi/SgiPlatformId.h>
#include <SgiPlatform.h>

/**

  This function returns the System ID of the platform

  This functions locates the NtFwConfig PPI and gets the base address of
  NT_FW_CONFIG DT from which the platform ID and config ID is obtained
  using FDT helper functions

  @param[out]      Pointer to the SGI_PLATFORM_DESCRIPTOR HoB
  @return          returns EFI_SUCCESS on success and EFI_INVALID_PARAMETER on error

**/

STATIC
EFI_STATUS
GetSgiSystemId (
  OUT SGI_PLATFORM_DESCRIPTOR   *HobData
)
{
  CONST UINT32                  *Property;
  INT32                         Offset;
  CONST VOID                    *NtFwCfgDtBlob;
  SGI_NT_FW_CONFIG_INFO_PPI     *NtFwConfigInfoPpi;
  EFI_STATUS                    Status;

  Status = PeiServicesLocatePpi (&gNtFwConfigDtInfoPpiGuid, 0, NULL,
             (VOID**)&NtFwConfigInfoPpi);
  if (EFI_ERROR (Status)) {
    DEBUG ((DEBUG_ERROR,
      "PeiServicesLocatePpi failed with error %r\n", Status));
    return EFI_INVALID_PARAMETER;
  }

  NtFwCfgDtBlob = (VOID *)(UINTN)NtFwConfigInfoPpi->NtFwConfigDtAddr;
  if (fdt_check_header (NtFwCfgDtBlob) != 0) {
    DEBUG ((DEBUG_ERROR, "Invalid DTB file %p passed\n", NtFwCfgDtBlob));
    return EFI_INVALID_PARAMETER;
  }

  Offset = fdt_subnode_offset (NtFwCfgDtBlob, 0, "system-id");
  if (Offset == -FDT_ERR_NOTFOUND) {
    DEBUG ((DEBUG_ERROR, "Invalid DTB : system-id node not found\n"));
    return EFI_INVALID_PARAMETER;
  }

  Property = fdt_getprop (NtFwCfgDtBlob, Offset, "platform-id", NULL);
  if (Property == NULL) {
    DEBUG ((DEBUG_ERROR, "platform-id property not found\n"));
    return EFI_INVALID_PARAMETER;
  }

  HobData->PlatformId = fdt32_to_cpu (*Property);

  Property = fdt_getprop (NtFwCfgDtBlob, Offset, "config-id", NULL);
  if (Property == NULL) {
    DEBUG ((DEBUG_ERROR, "config-id property not found\n"));
    return EFI_INVALID_PARAMETER;
  }

  HobData->ConfigId = fdt32_to_cpu (*Property);

  Property = fdt_getprop (NtFwCfgDtBlob, Offset, "multi-chip-mode", NULL);
  if (Property == NULL) {
    DEBUG ((DEBUG_WARN, "multi-chip-mode property not found\n"));
    HobData->MultiChipMode = 0;
  } else {
    HobData->MultiChipMode = fdt32_to_cpu (*Property);
  }

  return EFI_SUCCESS;
}

/**

 This function creates a System ID HOB and assigns PlatformId and
 ConfigId as the HobData

 @return asserts on error and returns EFI_INVALID_PARAMETER. On success
 returns EFI_SUCCESS

**/
EFI_STATUS
EFIAPI
SgiPlatformPeim (
 IN       EFI_PEI_FILE_HANDLE  FileHandle,
 IN CONST EFI_PEI_SERVICES     **PeiServices
)
{
  SGI_PLATFORM_DESCRIPTOR       *HobData;
  EFI_STATUS                    Status;

  // Create platform descriptor HOB
  HobData = (SGI_PLATFORM_DESCRIPTOR *)BuildGuidHob (
                                         &gArmSgiPlatformIdDescriptorGuid,
                                         sizeof (SGI_PLATFORM_DESCRIPTOR));

  // Get the system id from the platform specific nt_fw_config device tree
  if (HobData == NULL) {
    DEBUG ((DEBUG_ERROR, "Platform HOB is NULL\n"));
    ASSERT (FALSE);
    return EFI_OUT_OF_RESOURCES;
  }

  Status = GetSgiSystemId (HobData);
  if (EFI_ERROR (Status)) {
    ASSERT_EFI_ERROR (Status);
    return EFI_INVALID_PARAMETER;
  }

  if (HobData->PlatformId == 0) {
    ASSERT (FALSE);
    return EFI_INVALID_PARAMETER;
  }

  return EFI_SUCCESS;
}