/** @file

  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 <PiPei.h>
#include <Library/IoLib.h>
#include <Library/PeiServicesLib.h>
#include <Platform/MemoryMap.h>
#include <Ppi/EmbeddedGpio.h>

#define PDR(x)            (SYNQUACER_GPIO_BASE + 4 * (GPIO_PIN (x) >> 3))
#define DDR(x)            (SYNQUACER_GPIO_BASE + 0x10 + 4 * (GPIO_PIN (x) >> 3))
#define PFR(x)            (SYNQUACER_GPIO_BASE + 0x20 + 4 * (GPIO_PIN (x) >> 3))

#define GPIO_BIT(x)       (1U << (GPIO_PIN (x) % 8))

STATIC CONST UINTN mGpioPinCount = 32;

/**

  Gets the state of a GPIO pin

  @param This                   Pointer to protocol
  @param Gpio                   Which pin to read
  @param Value                  State of the pin

  @retval EFI_SUCCESS           GPIO state returned in Value
  @retval EFI_INVALID_PARAMETER Value is NULL
  @retval EFI_NOT_FOUND         Pin does not exit

**/
STATIC
EFI_STATUS
EFIAPI
GpioGet (
  IN  EMBEDDED_GPIO_PPI     *This,
  IN  EMBEDDED_GPIO_PIN     Gpio,
  OUT UINTN                 *Value
  )
{
  if (Value == NULL) {
    return EFI_INVALID_PARAMETER;
  }
  if (GPIO_PORT (Gpio) > 0 || GPIO_PIN (Gpio) >= mGpioPinCount) {
    return EFI_NOT_FOUND;
  }

  *Value = ((MmioRead32 (PDR (GPIO_PIN (Gpio))) & GPIO_BIT (Gpio)) != 0);

  return EFI_SUCCESS;
}

/**

  Sets the state of a GPIO pin

  @param This                   Pointer to protocol
  @param Gpio                   Which pin to modify
  @param Mode                   Mode to set

  @retval EFI_SUCCESS           GPIO set as requested
  @retval EFI_INVALID_PARAMETER Invalid mode
  @retval EFI_NOT_FOUND         Pin does not exit

**/
STATIC
EFI_STATUS
EFIAPI
GpioSet (
  IN EMBEDDED_GPIO_PPI      *This,
  IN EMBEDDED_GPIO_PIN      Gpio,
  IN EMBEDDED_GPIO_MODE     Mode
  )
{
  if (GPIO_PORT (Gpio) > 0 || GPIO_PIN (Gpio) >= mGpioPinCount) {
    return EFI_NOT_FOUND;
  }

  switch (Mode) {
  case GPIO_MODE_INPUT:
    MmioAnd32 (DDR (GPIO_PIN (Gpio)), ~GPIO_BIT (Gpio));
    break;

  case GPIO_MODE_OUTPUT_0:
    MmioOr32 (DDR (GPIO_PIN (Gpio)), GPIO_BIT (Gpio));
    MmioAnd32 (PDR (GPIO_PIN (Gpio)), ~GPIO_BIT (Gpio));
    break;

  case GPIO_MODE_OUTPUT_1:
    MmioOr32 (DDR (GPIO_PIN (Gpio)), GPIO_BIT (Gpio));
    MmioOr32 (PDR (GPIO_PIN (Gpio)), GPIO_BIT (Gpio));
    break;

  default:
    return EFI_INVALID_PARAMETER;
  }
  return EFI_SUCCESS;
}


/**

  Gets the mode (function) of a GPIO pin

  @param This                   Pointer to protocol
  @param Gpio                   Which pin
  @param Mode                   Pointer to output mode value

  @retval EFI_SUCCESS           Mode value retrieved
  @retval EFI_INVALID_PARAMETER Mode is NULL
  @retval EFI_NOT_FOUND         Pin does not exit

**/
STATIC
EFI_STATUS
EFIAPI
GpioGetMode (
  IN  EMBEDDED_GPIO_PPI     *This,
  IN  EMBEDDED_GPIO_PIN     Gpio,
  OUT EMBEDDED_GPIO_MODE    *Mode
  )
{
  if (Mode == NULL) {
    return EFI_INVALID_PARAMETER;
  }
  if (GPIO_PORT (Gpio) > 0 || GPIO_PIN (Gpio) >= mGpioPinCount) {
    return EFI_NOT_FOUND;
  }

  if (!(MmioRead32 (DDR (GPIO_PIN (Gpio))) & GPIO_BIT (Gpio))) {
    *Mode = GPIO_MODE_INPUT;
  } else if (!(MmioRead32 (PDR (GPIO_PIN (Gpio))) & GPIO_BIT (Gpio))) {
    *Mode = GPIO_MODE_OUTPUT_0;
  } else {
    *Mode = GPIO_MODE_OUTPUT_1;
  }
  return EFI_SUCCESS;
}


/**

  Sets the pull-up / pull-down resistor of a GPIO pin

  @param This                   Pointer to PPI
  @param Gpio                   Port/pin index
  @param Pull                   The pullup/pulldown mode to set

  @retval EFI_SUCCESS           Mode was set
  @retval EFI_NOT_FOUND         Pin does not exist
  @retval EFI_UNSUPPORTED       Action not supported

**/
STATIC
EFI_STATUS
EFIAPI
GpioSetPull (
  IN  EMBEDDED_GPIO_PPI     *This,
  IN  EMBEDDED_GPIO_PIN     Gpio,
  IN  EMBEDDED_GPIO_PULL    Pull
  )
{
  if (Pull != GPIO_PULL_NONE) {
    return EFI_UNSUPPORTED;
  }
  if (GPIO_PORT (Gpio) > 0 || GPIO_PIN (Gpio) >= mGpioPinCount) {
    return EFI_NOT_FOUND;
  }
  return EFI_SUCCESS;
}

STATIC EMBEDDED_GPIO_PPI mGpioPpi = {
  GpioGet,
  GpioSet,
  GpioGetMode,
  GpioSetPull,
};

STATIC CONST EFI_PEI_PPI_DESCRIPTOR mEmbeddedGpioPpiDescriptor = {
  EFI_PEI_PPI_DESCRIPTOR_PPI | EFI_PEI_PPI_DESCRIPTOR_TERMINATE_LIST,
  &gEdkiiEmbeddedGpioPpiGuid,
  &mGpioPpi
};

EFI_STATUS
EFIAPI
SynQuacerGpioPeiEntryPoint (
  IN       EFI_PEI_FILE_HANDLE      FfsHeader,
  IN       CONST EFI_PEI_SERVICES   **PeiServices
  )
{
  return PeiServicesInstallPpi (&mEmbeddedGpioPpiDescriptor);
}