1 files changed, 600 insertions, 0 deletions

diff --git a/drivers/scsi/isci/remote_node_table.c b/drivers/scsi/isci/remote_node_table.c
new file mode 100644
index 000000000000..8886146d9db2
--- /dev/null
+++ b/drivers/scsi/isci/remote_node_table.c
@@ -0,0 +1,600 @@
+/*
+ * 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 "sci_util.h"
+#include "sci_environment.h"
+#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 scic_sds_remote_node_table_get_group_index(
+        struct scic_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 scic_sds_remote_node_table_clear_group_index(
+        struct scic_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 scic_sds_remote_node_table_set_group_index(
+        struct scic_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 scic_sds_remote_node_table_set_node_index(
+        struct scic_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 scic_sds_remote_node_table_clear_node_index(
+        struct scic_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 scic_sds_remote_node_table_clear_group(
+        struct scic_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 scic_sds_remote_node_table_set_group(
+        struct scic_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 scic_sds_remote_node_table_get_group_value(
+        struct scic_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 scic_sds_remote_node_table_initialize(
+        struct scic_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++) {
+                scic_sds_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 */
+                scic_sds_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) {
+                scic_sds_remote_node_table_set_group_index(remote_node_table, 1, index);
+        } else if ((remote_node_entries % SCU_STP_REMOTE_NODE_COUNT) == 1) {
+                scic_sds_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 scic_sds_remote_node_table_allocate_single_remote_node(
+        struct scic_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 = scic_sds_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 = scic_sds_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);
+
+                                scic_sds_remote_node_table_clear_group_index(
+                                        remote_node_table, group_table_index, group_index
+                                        );
+
+                                scic_sds_remote_node_table_clear_node_index(
+                                        remote_node_table, remote_node_index
+                                        );
+
+                                if (group_table_index > 0) {
+                                        scic_sds_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 scic_sds_remote_node_table_allocate_triple_remote_node(
+        struct scic_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 = scic_sds_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;
+
+                scic_sds_remote_node_table_clear_group_index(
+                        remote_node_table, group_table_index, group_index
+                        );
+
+                scic_sds_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 scic_sds_remote_node_table_allocate_remote_node(
+        struct scic_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 =
+                        scic_sds_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 =
+                                scic_sds_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 =
+                                scic_sds_remote_node_table_allocate_single_remote_node(
+                                        remote_node_table, 2);
+                }
+        } else if (remote_node_count == SCU_STP_REMOTE_NODE_COUNT) {
+                remote_node_index =
+                        scic_sds_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 scic_sds_remote_node_table_release_single_remote_node(
+        struct scic_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 = scic_sds_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. */
+                scic_sds_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 */
+                scic_sds_remote_node_table_clear_group_index(remote_node_table, 0, group_index);
+                scic_sds_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. */
+                scic_sds_remote_node_table_clear_group_index(remote_node_table, 1, group_index);
+                scic_sds_remote_node_table_set_group_index(remote_node_table, 2, group_index);
+        }
+
+        scic_sds_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 scic_sds_remote_node_table_release_triple_remote_node(
+        struct scic_remote_node_table *remote_node_table,
+        u16 remote_node_index)
+{
+        u32 group_index;
+
+        group_index = remote_node_index / SCU_STP_REMOTE_NODE_COUNT;
+
+        scic_sds_remote_node_table_set_group_index(
+                remote_node_table, 2, group_index
+                );
+
+        scic_sds_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 scic_sds_remote_node_table_release_remote_node_index(
+        struct scic_remote_node_table *remote_node_table,
+        u32 remote_node_count,
+        u16 remote_node_index)
+{
+        if (remote_node_count == SCU_SSP_REMOTE_NODE_COUNT) {
+                scic_sds_remote_node_table_release_single_remote_node(
+                        remote_node_table, remote_node_index);
+        } else if (remote_node_count == SCU_STP_REMOTE_NODE_COUNT) {
+                scic_sds_remote_node_table_release_triple_remote_node(
+                        remote_node_table, remote_node_index);
+        }
+}
+