text: /*
   * Copyright (c) 2016 Linaro Limited
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  #include <misc/sys_log.h>
  #include <nanokernel.h>
  #include <device.h>
  #include <string.h>
  #include <flash.h>
  #include <errno.h>
  #include <init.h>
  #include <soc.h>
  
  #include "fsl_common.h"
  #include "fsl_flash.h"
  
  struct flash_priv {
  	flash_config_t config;
  };
  
  /*
   * Interrupt vectors could be executed from flash hence the need for locking.
   * The underlying KDSK driver takes care of copying the functions to SRAM.
   *
   * For more information, see the application note below on Read-While-Write
   * http://cache.freescale.com/files/32bit/doc/app_note/AN4695.pdf
   *
   */
  
  static int flash_ksdk_erase(struct device *dev, off_t offset, size_t len)
  {
  	struct flash_priv *priv = dev->driver_data;
  	uint32_t addr;
  	status_t rc;
  	int key;
  
  	addr = offset + priv->config.PFlashBlockBase;
  
  	key = irq_lock();
  	rc = FLASH_Erase(&priv->config, addr, len, kFLASH_apiEraseKey);
  	irq_unlock(key);
  
  	return (rc == kStatus_Success) ? 0 : -EINVAL;
  }
  
  static int flash_ksdk_read(struct device *dev, off_t offset,
  				void *data, size_t len)
  {
  	struct flash_priv *priv = dev->driver_data;
  	uint32_t addr;
  
  	/*
  	 * The KSDK supports different flash chips whose valid ranges are
  	 * hidden below the API: until the API export these ranges, we can not
  	 * do any generic validation
  	 */
  	addr = offset + priv->config.PFlashBlockBase;
  
  	memcpy(data, (void *) addr, len);
  
  	return 0;
  }
  
  static int flash_ksdk_write(struct device *dev, off_t offset,
  				const void *data, size_t len)
  {
  	struct flash_priv *priv = dev->driver_data;
  	uint32_t addr;
  	status_t rc;
  	int key;
  
  	addr = offset + priv->config.PFlashBlockBase;
  
  	key = irq_lock();
  	rc = FLASH_Program(&priv->config, addr, (uint32_t *) data, len);
  	irq_unlock(key);
  
  	return (rc == kStatus_Success) ? 0 : -EINVAL;
  }
  
  static int flash_ksdk_write_protection(struct device *dev, bool enable)
  {
  	return -EIO;
  }
  
  static struct flash_priv flash_data;
  
  static const struct flash_driver_api flash_ksdk_api = {
  	.write_protection = flash_ksdk_write_protection,
  	.erase = flash_ksdk_erase,
  	.write = flash_ksdk_write,
  	.read = flash_ksdk_read,
  };
  
  static int flash_ksdk_init(struct device *dev)
  {
  	struct flash_priv *priv = dev->driver_data;
  	status_t rc;
  
  	rc = FLASH_Init(&priv->config);
  
  	return (rc == kStatus_Success) ? 0 : -EIO;
  }
  
  DEVICE_AND_API_INIT(flash_ksdk, CONFIG_SOC_FLASH_KSDK_DEV_NAME,
  			flash_ksdk_init, &flash_data, NULL, POST_KERNEL,
  			CONFIG_KERNEL_INIT_PRIORITY_DEVICE, &flash_ksdk_api);
  
  