/** @file

  Copyright (c) 2016 - 2017, Socionext Inc. All rights reserved.<BR>
  Copyright (c) 2017, Linaro, Ltd. All rights reserved.<BR>

  This program and the accompanying materials
  are licensed and made available under the terms and conditions of the BSD License
  which accompanies this distribution.  The full text of the license may be found at
  http://opensource.org/licenses/bsd-license.php

  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

**/

#include "pfdep.h"

#include <Library/DebugLib.h>
#include <Library/DmaLib.h>
#include <Library/MemoryAllocationLib.h>
#include <Library/NetLib.h>
#include <Library/SynchronizationLib.h>

/**********************************************************************
 * Variable definitions
 **********************************************************************/
pfdep_debug_level_t pfdep_debug_level = PFDEP_DEBUG_LEVEL_NOTICE;


/**********************************************************************
 * Function definitions
 **********************************************************************/

VOID*
pfdep_malloc (
  IN  pfdep_uint32    len
  )
{
  return AllocatePool (len);
}

VOID
pfdep_free (
  IN  VOID       *addr
  )
{
  FreePool (addr);
}

pfdep_err_t
pfdep_dma_malloc (
  IN  pfdep_dev_handle_t        dev_handle,
  IN  pfdep_uint32              len,
  OUT VOID                      **addr_p,
  OUT pfdep_phys_addr_t         *phys_addr_p
  )
{
  EFI_STATUS    Status;
  UINTN         NumPages;
  UINTN         NumBytes;
  VOID          **Mapping;

  NumPages = EFI_SIZE_TO_PAGES (ALIGN_VARIABLE(len) + sizeof *Mapping);
  Status = DmaAllocateBuffer (EfiBootServicesData, NumPages, addr_p);
  if (EFI_ERROR (Status)) {
    return PFDEP_ERR_ALLOC;
  }

  //
  // Stash the address of the MAPINFO struct at the end of the buffer,
  // but make sure it appears aligned (the memory may be mapped uncached)
  //
  Mapping = (VOID **)((UINTN)*addr_p + ALIGN_VARIABLE(len));

  NumBytes = EFI_PAGES_TO_SIZE (NumPages);
  Status = DmaMap (MapOperationBusMasterCommonBuffer, *addr_p, &NumBytes,
             phys_addr_p, Mapping);

  if (EFI_ERROR (Status) || NumBytes < len) {
    DmaFreeBuffer (NumPages, *addr_p);
    return PFDEP_ERR_ALLOC;
  }

  return PFDEP_ERR_OK;
}

VOID
pfdep_dma_free (
  IN  pfdep_dev_handle_t        dev_handle,
  IN  pfdep_uint32              len,
  IN  VOID                      *addr,
  IN  pfdep_phys_addr_t         phys_addr
  )
{
  VOID          *Mapping;

  Mapping = *(VOID **)((UINTN)addr + ALIGN_VARIABLE(len));

  DmaUnmap (Mapping);
  DmaFreeBuffer (EFI_SIZE_TO_PAGES (ALIGN_VARIABLE(len) + sizeof Mapping),
    addr);
}

//
// On the receive path, we allocate a new packet and link it into the RX ring
// before returning the received packet to the caller. This means we perform
// one allocation and one free operation for each buffer received.
// So let's cache a single packet, and get rid of most of the alloc/free
// overhead on the RX path.
//
STATIC pfdep_pkt_handle_t mSparePacketBuffer;
STATIC UINT32 mSparePacketBufferSize;

pfdep_err_t
pfdep_alloc_pkt_buf (
  IN  pfdep_dev_handle_t        dev_handle,
  IN  pfdep_uint16              len,
  OUT VOID                      **addr_p,
  OUT pfdep_phys_addr_t         *phys_addr_p,
  OUT pfdep_pkt_handle_t        *pkt_handle_p
  )
{
  EFI_STATUS    Status;
  UINTN         NumBytes;

  NumBytes = ALIGN_VALUE (len, mCpu->DmaBufferAlignment);

  if (InterlockedCompareExchange32 (&mSparePacketBufferSize, len, 0) == len) {
    *pkt_handle_p = mSparePacketBuffer;
  } else {
    *pkt_handle_p = AllocateZeroPool (NumBytes + sizeof(PACKET_HANDLE) +
                                      (mCpu->DmaBufferAlignment - 8));
    if (*pkt_handle_p == NULL) {
      return PFDEP_ERR_ALLOC;
    }

    (*pkt_handle_p)->Buffer = ALIGN_POINTER (*pkt_handle_p,
                                             mCpu->DmaBufferAlignment);
  }

  *addr_p = (*pkt_handle_p)->Buffer;
  Status = DmaMap (MapOperationBusMasterWrite, *addr_p, &NumBytes, phys_addr_p,
             &(*pkt_handle_p)->Mapping);
  if (EFI_ERROR (Status) || NumBytes < len) {
    FreePool (*pkt_handle_p);
    return PFDEP_ERR_ALLOC;
  }
  return PFDEP_ERR_OK;
}

VOID
pfdep_free_pkt_buf (
  IN  pfdep_dev_handle_t        dev_handle,
  IN  pfdep_uint16              len,
  IN  VOID                      *addr,
  IN  pfdep_phys_addr_t         phys_addr,
  IN  pfdep_bool                last_flag,
  IN  pfdep_pkt_handle_t        pkt_handle
  )
{
  if (last_flag != PFDEP_TRUE) {
    return;
  }

  if (pkt_handle->Mapping != NULL) {
    DmaUnmap (pkt_handle->Mapping);
  }

  if (pkt_handle->RecycleForTx) {
      pkt_handle->Released = TRUE;
  } else if (!InterlockedCompareExchange32 (&mSparePacketBufferSize, 0, len)) {
    mSparePacketBuffer = pkt_handle;
  } else {
    FreePool (pkt_handle);
  }
}