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+/*
+ * 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);
+ }
+}
+
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