/*
   * 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.
   */
  
  /**
   * This file contains the implementation of the SCIC_SDS_REMOTE_NODE_TABLE
   *    public, protected, and private methods.
   *
   *
   */
  #include "remote_node_table.h"
  #include "remote_node_context.h"
  
  /**
   *
   * @remote_node_table: This is the remote node index table from which the
   *    selection will be made.
   * @group_table_index: This is the index to the group table from which to
   *    search for an available selection.
   *
   * This routine will find the bit position in absolute bit terms of the next 32
   * + bit position.  If there are available bits in the first u32 then it is
   * just bit position. u32 This is the absolute bit position for an available
   * group.
   */
  static u32 sci_remote_node_table_get_group_index(
  	struct sci_remote_node_table *remote_node_table,
  	u32 group_table_index)
  {
  	u32 dword_index;
  	u32 *group_table;
  	u32 bit_index;
  
  	group_table = remote_node_table->remote_node_groups[group_table_index];
  
  	for (dword_index = 0; dword_index < remote_node_table->group_array_size; dword_index++) {
  		if (group_table[dword_index] != 0) {
  			for (bit_index = 0; bit_index < 32; bit_index++) {
  				if ((group_table[dword_index] & (1 << bit_index)) != 0) {
  					return (dword_index * 32) + bit_index;
  				}
  			}
  		}
  	}
  
  	return SCIC_SDS_REMOTE_NODE_TABLE_INVALID_INDEX;
  }
  
  /**
   *
   * @out]: remote_node_table This the remote node table in which to clear the
   *    selector.
   * @set_index: This is the remote node selector in which the change will be
   *    made.
   * @group_index: This is the bit index in the table to be modified.
   *
   * This method will clear the group index entry in the specified group index
   * table. none
   */
  static void sci_remote_node_table_clear_group_index(
  	struct sci_remote_node_table *remote_node_table,
  	u32 group_table_index,
  	u32 group_index)
  {
  	u32 dword_index;
  	u32 bit_index;
  	u32 *group_table;
  
  	BUG_ON(group_table_index >= SCU_STP_REMOTE_NODE_COUNT);
  	BUG_ON(group_index >= (u32)(remote_node_table->group_array_size * 32));
  
  	dword_index = group_index / 32;
  	bit_index   = group_index % 32;
  	group_table = remote_node_table->remote_node_groups[group_table_index];
  
  	group_table[dword_index] = group_table[dword_index] & ~(1 << bit_index);
  }
  
  /**
   *
   * @out]: remote_node_table This the remote node table in which to set the
   *    selector.
   * @group_table_index: This is the remote node selector in which the change
   *    will be made.
   * @group_index: This is the bit position in the table to be modified.
   *
   * This method will set the group index bit entry in the specified gropu index
   * table. none
   */
  static void sci_remote_node_table_set_group_index(
  	struct sci_remote_node_table *remote_node_table,
  	u32 group_table_index,
  	u32 group_index)
  {
  	u32 dword_index;
  	u32 bit_index;
  	u32 *group_table;
  
  	BUG_ON(group_table_index >= SCU_STP_REMOTE_NODE_COUNT);
  	BUG_ON(group_index >= (u32)(remote_node_table->group_array_size * 32));
  
  	dword_index = group_index / 32;
  	bit_index   = group_index % 32;
  	group_table = remote_node_table->remote_node_groups[group_table_index];
  
  	group_table[dword_index] = group_table[dword_index] | (1 << bit_index);
  }
  
  /**
   *
   * @out]: remote_node_table This is the remote node table in which to modify
   *    the remote node availability.
   * @remote_node_index: This is the remote node index that is being returned to
   *    the table.
   *
   * This method will set the remote to available in the remote node allocation
   * table. none
   */
  static void sci_remote_node_table_set_node_index(
  	struct sci_remote_node_table *remote_node_table,
  	u32 remote_node_index)
  {
  	u32 dword_location;
  	u32 dword_remainder;
  	u32 slot_normalized;
  	u32 slot_position;
  
  	BUG_ON(
  		(remote_node_table->available_nodes_array_size * SCIC_SDS_REMOTE_NODE_SETS_PER_DWORD)
  		<= (remote_node_index / SCU_STP_REMOTE_NODE_COUNT)
  		);
  
  	dword_location  = remote_node_index / SCIC_SDS_REMOTE_NODES_PER_DWORD;
  	dword_remainder = remote_node_index % SCIC_SDS_REMOTE_NODES_PER_DWORD;
  	slot_normalized = (dword_remainder / SCU_STP_REMOTE_NODE_COUNT) * sizeof(u32);
  	slot_position   = remote_node_index % SCU_STP_REMOTE_NODE_COUNT;
  
  	remote_node_table->available_remote_nodes[dword_location] |=
  		1 << (slot_normalized + slot_position);
  }
  
  /**
   *
   * @out]: remote_node_table This is the remote node table from which to clear
   *    the available remote node bit.
   * @remote_node_index: This is the remote node index which is to be cleared
   *    from the table.
   *
   * This method clears the remote node index from the table of available remote
   * nodes. none
   */
  static void sci_remote_node_table_clear_node_index(
  	struct sci_remote_node_table *remote_node_table,
  	u32 remote_node_index)
  {
  	u32 dword_location;
  	u32 dword_remainder;
  	u32 slot_position;
  	u32 slot_normalized;
  
  	BUG_ON(
  		(remote_node_table->available_nodes_array_size * SCIC_SDS_REMOTE_NODE_SETS_PER_DWORD)
  		<= (remote_node_index / SCU_STP_REMOTE_NODE_COUNT)
  		);
  
  	dword_location  = remote_node_index / SCIC_SDS_REMOTE_NODES_PER_DWORD;
  	dword_remainder = remote_node_index % SCIC_SDS_REMOTE_NODES_PER_DWORD;
  	slot_normalized = (dword_remainder / SCU_STP_REMOTE_NODE_COUNT) * sizeof(u32);
  	slot_position   = remote_node_index % SCU_STP_REMOTE_NODE_COUNT;
  
  	remote_node_table->available_remote_nodes[dword_location] &=
  		~(1 << (slot_normalized + slot_position));
  }
  
  /**
   *
   * @out]: remote_node_table The remote node table from which the slot will be
   *    cleared.
   * @group_index: The index for the slot that is to be cleared.
   *
   * This method clears the entire table slot at the specified slot index. none
   */
  static void sci_remote_node_table_clear_group(
  	struct sci_remote_node_table *remote_node_table,
  	u32 group_index)
  {
  	u32 dword_location;
  	u32 dword_remainder;
  	u32 dword_value;
  
  	BUG_ON(
  		(remote_node_table->available_nodes_array_size * SCIC_SDS_REMOTE_NODE_SETS_PER_DWORD)
  		<= (group_index / SCU_STP_REMOTE_NODE_COUNT)
  		);
  
  	dword_location  = group_index / SCIC_SDS_REMOTE_NODE_SETS_PER_DWORD;
  	dword_remainder = group_index % SCIC_SDS_REMOTE_NODE_SETS_PER_DWORD;
  
  	dword_value = remote_node_table->available_remote_nodes[dword_location];
  	dword_value &= ~(SCIC_SDS_REMOTE_NODE_TABLE_FULL_SLOT_VALUE << (dword_remainder * 4));
  	remote_node_table->available_remote_nodes[dword_location] = dword_value;
  }
  
  /**
   *
   * @remote_node_table:
   *
   * THis method sets an entire remote node group in the remote node table.
   */
  static void sci_remote_node_table_set_group(
  	struct sci_remote_node_table *remote_node_table,
  	u32 group_index)
  {
  	u32 dword_location;
  	u32 dword_remainder;
  	u32 dword_value;
  
  	BUG_ON(
  		(remote_node_table->available_nodes_array_size * SCIC_SDS_REMOTE_NODE_SETS_PER_DWORD)
  		<= (group_index / SCU_STP_REMOTE_NODE_COUNT)
  		);
  
  	dword_location  = group_index / SCIC_SDS_REMOTE_NODE_SETS_PER_DWORD;
  	dword_remainder = group_index % SCIC_SDS_REMOTE_NODE_SETS_PER_DWORD;
  
  	dword_value = remote_node_table->available_remote_nodes[dword_location];
  	dword_value |= (SCIC_SDS_REMOTE_NODE_TABLE_FULL_SLOT_VALUE << (dword_remainder * 4));
  	remote_node_table->available_remote_nodes[dword_location] = dword_value;
  }
  
  /**
   *
   * @remote_node_table: This is the remote node table that for which the group
   *    value is to be returned.
   * @group_index: This is the group index to use to find the group value.
   *
   * This method will return the group value for the specified group index. The
   * bit values at the specified remote node group index.
   */
  static u8 sci_remote_node_table_get_group_value(
  	struct sci_remote_node_table *remote_node_table,
  	u32 group_index)
  {
  	u32 dword_location;
  	u32 dword_remainder;
  	u32 dword_value;
  
  	dword_location  = group_index / SCIC_SDS_REMOTE_NODE_SETS_PER_DWORD;
  	dword_remainder = group_index % SCIC_SDS_REMOTE_NODE_SETS_PER_DWORD;
  
  	dword_value = remote_node_table->available_remote_nodes[dword_location];
  	dword_value &= (SCIC_SDS_REMOTE_NODE_TABLE_FULL_SLOT_VALUE << (dword_remainder * 4));
  	dword_value = dword_value >> (dword_remainder * 4);
  
  	return (u8)dword_value;
  }
  
  /**
   *
   * @out]: remote_node_table The remote that which is to be initialized.
   * @remote_node_entries: The number of entries to put in the table.
   *
   * This method will initialize the remote node table for use. none
   */
  void sci_remote_node_table_initialize(
  	struct sci_remote_node_table *remote_node_table,
  	u32 remote_node_entries)
  {
  	u32 index;
  
  	/*
  	 * Initialize the raw data we could improve the speed by only initializing
  	 * those entries that we are actually going to be used */
  	memset(
  		remote_node_table->available_remote_nodes,
  		0x00,
  		sizeof(remote_node_table->available_remote_nodes)
  		);
  
  	memset(
  		remote_node_table->remote_node_groups,
  		0x00,
  		sizeof(remote_node_table->remote_node_groups)
  		);
  
  	/* Initialize the available remote node sets */
  	remote_node_table->available_nodes_array_size = (u16)
  							(remote_node_entries / SCIC_SDS_REMOTE_NODES_PER_DWORD)
  							+ ((remote_node_entries % SCIC_SDS_REMOTE_NODES_PER_DWORD) != 0);
  
  
  	/* Initialize each full DWORD to a FULL SET of remote nodes */
  	for (index = 0; index < remote_node_entries; index++) {
  		sci_remote_node_table_set_node_index(remote_node_table, index);
  	}
  
  	remote_node_table->group_array_size = (u16)
  					      (remote_node_entries / (SCU_STP_REMOTE_NODE_COUNT * 32))
  					      + ((remote_node_entries % (SCU_STP_REMOTE_NODE_COUNT * 32)) != 0);
  
  	for (index = 0; index < (remote_node_entries / SCU_STP_REMOTE_NODE_COUNT); index++) {
  		/*
  		 * These are all guaranteed to be full slot values so fill them in the
  		 * available sets of 3 remote nodes */
  		sci_remote_node_table_set_group_index(remote_node_table, 2, index);
  	}
  
  	/* Now fill in any remainders that we may find */
  	if ((remote_node_entries % SCU_STP_REMOTE_NODE_COUNT) == 2) {
  		sci_remote_node_table_set_group_index(remote_node_table, 1, index);
  	} else if ((remote_node_entries % SCU_STP_REMOTE_NODE_COUNT) == 1) {
  		sci_remote_node_table_set_group_index(remote_node_table, 0, index);
  	}
  }
  
  /**
   *
   * @out]: remote_node_table The remote node table from which to allocate a
   *    remote node.
   * @table_index: The group index that is to be used for the search.
   *
   * This method will allocate a single RNi from the remote node table.  The
   * table index will determine from which remote node group table to search.
   * This search may fail and another group node table can be specified.  The
   * function is designed to allow a serach of the available single remote node
   * group up to the triple remote node group.  If an entry is found in the
   * specified table the remote node is removed and the remote node groups are
   * updated. The RNi value or an invalid remote node context if an RNi can not
   * be found.
   */
  static u16 sci_remote_node_table_allocate_single_remote_node(
  	struct sci_remote_node_table *remote_node_table,
  	u32 group_table_index)
  {
  	u8 index;
  	u8 group_value;
  	u32 group_index;
  	u16 remote_node_index = SCIC_SDS_REMOTE_NODE_CONTEXT_INVALID_INDEX;
  
  	group_index = sci_remote_node_table_get_group_index(
  		remote_node_table, group_table_index);
  
  	/* We could not find an available slot in the table selector 0 */
  	if (group_index != SCIC_SDS_REMOTE_NODE_TABLE_INVALID_INDEX) {
  		group_value = sci_remote_node_table_get_group_value(
  			remote_node_table, group_index);
  
  		for (index = 0; index < SCU_STP_REMOTE_NODE_COUNT; index++) {
  			if (((1 << index) & group_value) != 0) {
  				/* We have selected a bit now clear it */
  				remote_node_index = (u16)(group_index * SCU_STP_REMOTE_NODE_COUNT
  							  + index);
  
  				sci_remote_node_table_clear_group_index(
  					remote_node_table, group_table_index, group_index
  					);
  
  				sci_remote_node_table_clear_node_index(
  					remote_node_table, remote_node_index
  					);
  
  				if (group_table_index > 0) {
  					sci_remote_node_table_set_group_index(
  						remote_node_table, group_table_index - 1, group_index
  						);
  				}
  
  				break;
  			}
  		}
  	}
  
  	return remote_node_index;
  }
  
  /**
   *
   * @remote_node_table: This is the remote node table from which to allocate the
   *    remote node entries.
   * @group_table_index: THis is the group table index which must equal two (2)
   *    for this operation.
   *
   * This method will allocate three consecutive remote node context entries. If
   * there are no remaining triple entries the function will return a failure.
   * The remote node index that represents three consecutive remote node entries
   * or an invalid remote node context if none can be found.
   */
  static u16 sci_remote_node_table_allocate_triple_remote_node(
  	struct sci_remote_node_table *remote_node_table,
  	u32 group_table_index)
  {
  	u32 group_index;
  	u16 remote_node_index = SCIC_SDS_REMOTE_NODE_CONTEXT_INVALID_INDEX;
  
  	group_index = sci_remote_node_table_get_group_index(
  		remote_node_table, group_table_index);
  
  	if (group_index != SCIC_SDS_REMOTE_NODE_TABLE_INVALID_INDEX) {
  		remote_node_index = (u16)group_index * SCU_STP_REMOTE_NODE_COUNT;
  
  		sci_remote_node_table_clear_group_index(
  			remote_node_table, group_table_index, group_index
  			);
  
  		sci_remote_node_table_clear_group(
  			remote_node_table, group_index
  			);
  	}
  
  	return remote_node_index;
  }
  
  /**
   *
   * @remote_node_table: This is the remote node table from which the remote node
   *    allocation is to take place.
   * @remote_node_count: This is ther remote node count which is one of
   *    SCU_SSP_REMOTE_NODE_COUNT(1) or SCU_STP_REMOTE_NODE_COUNT(3).
   *
   * This method will allocate a remote node that mataches the remote node count
   * specified by the caller.  Valid values for remote node count is
   * SCU_SSP_REMOTE_NODE_COUNT(1) or SCU_STP_REMOTE_NODE_COUNT(3). u16 This is
   * the remote node index that is returned or an invalid remote node context.
   */
  u16 sci_remote_node_table_allocate_remote_node(
  	struct sci_remote_node_table *remote_node_table,
  	u32 remote_node_count)
  {
  	u16 remote_node_index = SCIC_SDS_REMOTE_NODE_CONTEXT_INVALID_INDEX;
  
  	if (remote_node_count == SCU_SSP_REMOTE_NODE_COUNT) {
  		remote_node_index =
  			sci_remote_node_table_allocate_single_remote_node(
  				remote_node_table, 0);
  
  		if (remote_node_index == SCIC_SDS_REMOTE_NODE_CONTEXT_INVALID_INDEX) {
  			remote_node_index =
  				sci_remote_node_table_allocate_single_remote_node(
  					remote_node_table, 1);
  		}
  
  		if (remote_node_index == SCIC_SDS_REMOTE_NODE_CONTEXT_INVALID_INDEX) {
  			remote_node_index =
  				sci_remote_node_table_allocate_single_remote_node(
  					remote_node_table, 2);
  		}
  	} else if (remote_node_count == SCU_STP_REMOTE_NODE_COUNT) {
  		remote_node_index =
  			sci_remote_node_table_allocate_triple_remote_node(
  				remote_node_table, 2);
  	}
  
  	return remote_node_index;
  }
  
  /**
   *
   * @remote_node_table:
   *
   * This method will free a single remote node index back to the remote node
   * table.  This routine will update the remote node groups
   */
  static void sci_remote_node_table_release_single_remote_node(
  	struct sci_remote_node_table *remote_node_table,
  	u16 remote_node_index)
  {
  	u32 group_index;
  	u8 group_value;
  
  	group_index = remote_node_index / SCU_STP_REMOTE_NODE_COUNT;
  
  	group_value = sci_remote_node_table_get_group_value(remote_node_table, group_index);
  
  	/*
  	 * Assert that we are not trying to add an entry to a slot that is already
  	 * full. */
  	BUG_ON(group_value == SCIC_SDS_REMOTE_NODE_TABLE_FULL_SLOT_VALUE);
  
  	if (group_value == 0x00) {
  		/*
  		 * There are no entries in this slot so it must be added to the single
  		 * slot table. */
  		sci_remote_node_table_set_group_index(remote_node_table, 0, group_index);
  	} else if ((group_value & (group_value - 1)) == 0) {
  		/*
  		 * There is only one entry in this slot so it must be moved from the
  		 * single slot table to the dual slot table */
  		sci_remote_node_table_clear_group_index(remote_node_table, 0, group_index);
  		sci_remote_node_table_set_group_index(remote_node_table, 1, group_index);
  	} else {
  		/*
  		 * There are two entries in the slot so it must be moved from the dual
  		 * slot table to the tripple slot table. */
  		sci_remote_node_table_clear_group_index(remote_node_table, 1, group_index);
  		sci_remote_node_table_set_group_index(remote_node_table, 2, group_index);
  	}
  
  	sci_remote_node_table_set_node_index(remote_node_table, remote_node_index);
  }
  
  /**
   *
   * @remote_node_table: This is the remote node table to which the remote node
   *    index is to be freed.
   *
   * This method will release a group of three consecutive remote nodes back to
   * the free remote nodes.
   */
  static void sci_remote_node_table_release_triple_remote_node(
  	struct sci_remote_node_table *remote_node_table,
  	u16 remote_node_index)
  {
  	u32 group_index;
  
  	group_index = remote_node_index / SCU_STP_REMOTE_NODE_COUNT;
  
  	sci_remote_node_table_set_group_index(
  		remote_node_table, 2, group_index
  		);
  
  	sci_remote_node_table_set_group(remote_node_table, group_index);
  }
  
  /**
   *
   * @remote_node_table: The remote node table to which the remote node index is
   *    to be freed.
   * @remote_node_count: This is the count of consecutive remote nodes that are
   *    to be freed.
   *
   * This method will release the remote node index back into the remote node
   * table free pool.
   */
  void sci_remote_node_table_release_remote_node_index(
  	struct sci_remote_node_table *remote_node_table,
  	u32 remote_node_count,
  	u16 remote_node_index)
  {
  	if (remote_node_count == SCU_SSP_REMOTE_NODE_COUNT) {
  		sci_remote_node_table_release_single_remote_node(
  			remote_node_table, remote_node_index);
  	} else if (remote_node_count == SCU_STP_REMOTE_NODE_COUNT) {
  		sci_remote_node_table_release_triple_remote_node(
  			remote_node_table, remote_node_index);
  	}
  }