drivers/scsi/isci/unsolicited_frame_control.c - kernel/mindspeed - Git at Google

 /*
  * 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;
 }
	/*
	* 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;
	}