drivers/scsi/isci/remote_node_table.h

   1 /*
   2  * This file is provided under a dual BSD/GPLv2 license.  When using or
   3  * redistributing this file, you may do so under either license.
   4  *
   5  * GPL LICENSE SUMMARY
   6  *
   7  * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of version 2 of the GNU General Public License as
  11  * published by the Free Software Foundation.
  12  *
  13  * This program is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  21  * The full GNU General Public License is included in this distribution
  22  * in the file called LICENSE.GPL.
  23  *
  24  * BSD LICENSE
  25  *
  26  * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
  27  * All rights reserved.
  28  *
  29  * Redistribution and use in source and binary forms, with or without
  30  * modification, are permitted provided that the following conditions
  31  * are met:
  32  *
  33  *   * Redistributions of source code must retain the above copyright
  34  *     notice, this list of conditions and the following disclaimer.
  35  *   * Redistributions in binary form must reproduce the above copyright
  36  *     notice, this list of conditions and the following disclaimer in
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  38  *     distribution.
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  41  *     from this software without specific prior written permission.
  42  *
  43  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  44  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  45  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  46  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  47  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  48  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  49  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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  53  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  54  */
  55
  56 #ifndef _SCIC_SDS_REMOTE_NODE_TABLE_H_
  57 #define _SCIC_SDS_REMOTE_NODE_TABLE_H_
  58
  59 /**
  60  * This file contains the structures, constants and prototypes used for the
  61  *    remote node table.
  62  *
  63  *
  64  */
  65
  66 #include "sci_controller_constants.h"
  67
  68 /**
  69  *
  70  *
  71  * Remote node sets are sets of remote node index in the remtoe node table The
  72  * SCU hardware requires that STP remote node entries take three consecutive
  73  * remote node index so the table is arranged in sets of three. The bits are
  74  * used as 0111 0111 to make a byte and the bits define the set of three remote
  75  * nodes to use as a sequence.
  76  */
  77 #define SCIC_SDS_REMOTE_NODE_SETS_PER_BYTE 2
  78
  79 /**
  80  *
  81  *
  82  * Since the remote node table is organized as DWORDS take the remote node sets
  83  * in bytes and represent them in DWORDs. The lowest ordered bits are the ones
  84  * used in case full DWORD is not being used. i.e. 0000 0000 0000 0000 0111
  85  * 0111 0111 0111 // if only a single WORD is in use in the DWORD.
  86  */
  87 #define SCIC_SDS_REMOTE_NODE_SETS_PER_DWORD \
  88         (sizeof(u32) * SCIC_SDS_REMOTE_NODE_SETS_PER_BYTE)
  89 /**
  90  *
  91  *
  92  * This is a count of the numeber of remote nodes that can be represented in a
  93  * byte
  94  */
  95 #define SCIC_SDS_REMOTE_NODES_PER_BYTE  \
  96         (SCU_STP_REMOTE_NODE_COUNT * SCIC_SDS_REMOTE_NODE_SETS_PER_BYTE)
  97
  98 /**
  99  *
 100  *
 101  * This is a count of the number of remote nodes that can be represented in a
 102  * DWROD
 103  */
 104 #define SCIC_SDS_REMOTE_NODES_PER_DWORD \
 105         (sizeof(u32) * SCIC_SDS_REMOTE_NODES_PER_BYTE)
 106
 107 /**
 108  *
 109  *
 110  * This is the number of bits in a remote node group
 111  */
 112 #define SCIC_SDS_REMOTE_NODES_BITS_PER_GROUP   4
 113
 114 #define SCIC_SDS_REMOTE_NODE_TABLE_INVALID_INDEX      (0xFFFFFFFF)
 115 #define SCIC_SDS_REMOTE_NODE_TABLE_FULL_SLOT_VALUE    (0x07)
 116 #define SCIC_SDS_REMOTE_NODE_TABLE_EMPTY_SLOT_VALUE   (0x00)
 117
 118 /**
 119  *
 120  *
 121  * Expander attached sata remote node count
 122  */
 123 #define SCU_STP_REMOTE_NODE_COUNT        3
 124
 125 /**
 126  *
 127  *
 128  * Expander or direct attached ssp remote node count
 129  */
 130 #define SCU_SSP_REMOTE_NODE_COUNT        1
 131
 132 /**
 133  *
 134  *
 135  * Direct attached STP remote node count
 136  */
 137 #define SCU_SATA_REMOTE_NODE_COUNT       1
 138
 139 /**
 140  * struct scic_remote_node_table -
 141  *
 142  *
 143  */
 144 struct scic_remote_node_table {
 145         /**
 146          * This field contains the array size in dwords
 147          */
 148         u16 available_nodes_array_size;
 149
 150         /**
 151          * This field contains the array size of the
 152          */
 153         u16 group_array_size;
 154
 155         /**
 156          * This field is the array of available remote node entries in bits.
 157          * Because of the way STP remote node data is allocated on the SCU hardware
 158          * the remote nodes must occupy three consecutive remote node context
 159          * entries.  For ease of allocation and de-allocation we have broken the
 160          * sets of three into a single nibble.  When the STP RNi is allocated all
 161          * of the bits in the nibble are cleared.  This math results in a table size
 162          * of MAX_REMOTE_NODES / CONSECUTIVE RNi ENTRIES for STP / 2 entries per byte.
 163          */
 164         u32 available_remote_nodes[
 165                 (SCI_MAX_REMOTE_DEVICES / SCIC_SDS_REMOTE_NODES_PER_DWORD)
 166                 + ((SCI_MAX_REMOTE_DEVICES % SCIC_SDS_REMOTE_NODES_PER_DWORD) != 0)];
 167
 168         /**
 169          * This field is the nibble selector for the above table.  There are three
 170          * possible selectors each for fast lookup when trying to find one, two or
 171          * three remote node entries.
 172          */
 173         u32 remote_node_groups[
 174                 SCU_STP_REMOTE_NODE_COUNT][
 175                 (SCI_MAX_REMOTE_DEVICES / (32 * SCU_STP_REMOTE_NODE_COUNT))
 176                 + ((SCI_MAX_REMOTE_DEVICES % (32 * SCU_STP_REMOTE_NODE_COUNT)) != 0)];
 177
 178 };
 179
 180 /* --------------------------------------------------------------------------- */
 181
 182 void scic_sds_remote_node_table_initialize(
 183         struct scic_remote_node_table *remote_node_table,
 184         u32 remote_node_entries);
 185
 186 u16 scic_sds_remote_node_table_allocate_remote_node(
 187         struct scic_remote_node_table *remote_node_table,
 188         u32 remote_node_count);
 189
 190 void scic_sds_remote_node_table_release_remote_node_index(
 191         struct scic_remote_node_table *remote_node_table,
 192         u32 remote_node_count,
 193         u16 remote_node_index);
 194
 195 #endif /* _SCIC_SDS_REMOTE_NODE_TABLE_H_ */