/*
   * This file is provided under a dual BSD/GPLv2 license.  When using or
   * redistributing this file, you may do so under either license.
   *
   * GPL LICENSE SUMMARY
   *
   * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of version 2 of the GNU General Public License as
   * published by the Free Software Foundation.
   *
   * This program is distributed in the hope that it will be useful, but
   * WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   * General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
   * The full GNU General Public License is included in this distribution
   * in the file called LICENSE.GPL.
   *
   * BSD LICENSE
   *
   * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   *   * Redistributions of source code must retain the above copyright
   *     notice, this list of conditions and the following disclaimer.
   *   * Redistributions in binary form must reproduce the above copyright
   *     notice, this list of conditions and the following disclaimer in
   *     the documentation and/or other materials provided with the
   *     distribution.
   *   * Neither the name of Intel Corporation nor the names of its
   *     contributors may be used to endorse or promote products derived
   *     from this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
   * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */

  #include "host.h"

  #include "unsolicited_frame_control.h"
  #include "registers.h"

  int sci_unsolicited_frame_control_construct(struct isci_host *ihost)

  {

  	struct sci_unsolicited_frame_control *uf_control = &ihost->uf_control;
  	struct sci_unsolicited_frame *uf;

  	u32 buf_len, header_len, i;
  	dma_addr_t dma;

  	size_t size;

  	void *virt;

  
  	/*
  	 * Prepare all of the memory sizes for the UF headers, UF address

  	 * table, and UF buffers themselves.
  	 */

  	buf_len = SCU_MAX_UNSOLICITED_FRAMES * SCU_UNSOLICITED_FRAME_BUFFER_SIZE;
  	header_len = SCU_MAX_UNSOLICITED_FRAMES * sizeof(struct scu_unsolicited_frame_header);

  	size = buf_len + header_len + SCU_MAX_UNSOLICITED_FRAMES * sizeof(uf_control->address_table.array[0]);

  	/*
  	 * The Unsolicited Frame buffers are set at the start of the UF

  	 * memory descriptor entry. The headers and address table will be
  	 * placed after the buffers.
  	 */

  	virt = dmam_alloc_coherent(&ihost->pdev->dev, size, &dma, GFP_KERNEL);

  	if (!virt)

  		return -ENOMEM;

  
  	/*
  	 * Program the location of the UF header table into the SCU.
  	 * Notes:
  	 * - The address must align on a 64-byte boundary. Guaranteed to be
  	 *   on 64-byte boundary already 1KB boundary for unsolicited frames.
  	 * - Program unused header entries to overlap with the last
  	 *   unsolicited frame.  The silicon will never DMA to these unused
  	 *   headers, since we program the UF address table pointers to

  	 *   NULL.
  	 */

  	uf_control->headers.physical_address = dma + buf_len;
  	uf_control->headers.array = virt + buf_len;

  
  	/*
  	 * Program the location of the UF address table into the SCU.
  	 * Notes:
  	 * - The address must align on a 64-bit boundary. Guaranteed to be on 64
  	 *   byte boundary already due to above programming headers being on a

  	 *   64-bit boundary and headers are on a 64-bytes in size.
  	 */

  	uf_control->address_table.physical_address = dma + buf_len + header_len;
  	uf_control->address_table.array = virt + buf_len + header_len;

  	uf_control->get = 0;
  
  	/*
  	 * UF buffer requirements are:
  	 * - The last entry in the UF queue is not NULL.
  	 * - There is a power of 2 number of entries (NULL or not-NULL)
  	 *   programmed into the queue.
  	 * - Aligned on a 1KB boundary. */
  
  	/*

  	 * Program the actual used UF buffers into the UF address table and
  	 * the controller's array of UFs.
  	 */
  	for (i = 0; i < SCU_MAX_UNSOLICITED_FRAMES; i++) {
  		uf = &uf_control->buffers.array[i];
  
  		uf_control->address_table.array[i] = dma;
  
  		uf->buffer = virt;
  		uf->header = &uf_control->headers.array[i];
  		uf->state  = UNSOLICITED_FRAME_EMPTY;
  
  		/*
  		 * Increment the address of the physical and virtual memory
  		 * pointers. Everything is aligned on 1k boundary with an
  		 * increment of 1k.
  		 */
  		virt += SCU_UNSOLICITED_FRAME_BUFFER_SIZE;
  		dma += SCU_UNSOLICITED_FRAME_BUFFER_SIZE;
  	}

  
  	return 0;

  }

  enum sci_status sci_unsolicited_frame_control_get_header(struct sci_unsolicited_frame_control *uf_control,
  							 u32 frame_index,
  							 void **frame_header)

  {

  	if (frame_index < SCU_MAX_UNSOLICITED_FRAMES) {

  		/* Skip the first word in the frame since this is a controll word used
  		 * by the hardware.
  		 */

  		*frame_header = &uf_control->buffers.array[frame_index].header->data;
  
  		return SCI_SUCCESS;
  	}
  
  	return SCI_FAILURE_INVALID_PARAMETER_VALUE;
  }

  enum sci_status sci_unsolicited_frame_control_get_buffer(struct sci_unsolicited_frame_control *uf_control,
  							 u32 frame_index,
  							 void **frame_buffer)

  {

  	if (frame_index < SCU_MAX_UNSOLICITED_FRAMES) {

  		*frame_buffer = uf_control->buffers.array[frame_index].buffer;
  
  		return SCI_SUCCESS;
  	}
  
  	return SCI_FAILURE_INVALID_PARAMETER_VALUE;
  }

  bool sci_unsolicited_frame_control_release_frame(struct sci_unsolicited_frame_control *uf_control,
  						 u32 frame_index)

  {
  	u32 frame_get;
  	u32 frame_cycle;

  	frame_get   = uf_control->get & (SCU_MAX_UNSOLICITED_FRAMES - 1);
  	frame_cycle = uf_control->get & SCU_MAX_UNSOLICITED_FRAMES;

  
  	/*
  	 * In the event there are NULL entries in the UF table, we need to
  	 * advance the get pointer in order to find out if this frame should

  	 * be released (i.e. update the get pointer)
  	 */

  	while (lower_32_bits(uf_control->address_table.array[frame_get]) == 0 &&
  	       upper_32_bits(uf_control->address_table.array[frame_get]) == 0 &&
  	       frame_get < SCU_MAX_UNSOLICITED_FRAMES)

  		frame_get++;
  
  	/*
  	 * The table has a NULL entry as it's last element.  This is

  	 * illegal.
  	 */

  	BUG_ON(frame_get >= SCU_MAX_UNSOLICITED_FRAMES);

  	if (frame_index >= SCU_MAX_UNSOLICITED_FRAMES)
  		return false;

  	uf_control->buffers.array[frame_index].state = UNSOLICITED_FRAME_RELEASED;

  	if (frame_get != frame_index) {

  		/*

  		 * Frames remain in use until we advance the get pointer
  		 * so there is nothing we can do here
  		 */
  		return false;
  	}

  	/*
  	 * The frame index is equal to the current get pointer so we
  	 * can now free up all of the frame entries that
  	 */
  	while (uf_control->buffers.array[frame_get].state == UNSOLICITED_FRAME_RELEASED) {
  		uf_control->buffers.array[frame_get].state = UNSOLICITED_FRAME_EMPTY;
  
  		if (frame_get+1 == SCU_MAX_UNSOLICITED_FRAMES-1) {
  			frame_cycle ^= SCU_MAX_UNSOLICITED_FRAMES;
  			frame_get = 0;
  		} else
  			frame_get++;

  	}

  	uf_control->get = SCU_UFQGP_GEN_BIT(ENABLE_BIT) | frame_cycle | frame_get;

  	return true;
  }