scsi/isci/remote_node_table.h

0001 /*
0002  * This file is provided under a dual BSD/GPLv2 license.  When using or
0003  * redistributing this file, you may do so under either license.
0004  *
0005  * GPL LICENSE SUMMARY
0006  *
0007  * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
0008  *
0009  * This program is free software; you can redistribute it and/or modify
0010  * it under the terms of version 2 of the GNU General Public License as
0011  * published by the Free Software Foundation.
0012  *
0013  * This program is distributed in the hope that it will be useful, but
0014  * WITHOUT ANY WARRANTY; without even the implied warranty of
0015  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
0016  * General Public License for more details.
0017  *
0018  * You should have received a copy of the GNU General Public License
0019  * along with this program; if not, write to the Free Software
0020  * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
0021  * The full GNU General Public License is included in this distribution
0022  * in the file called LICENSE.GPL.
0023  *
0024  * BSD LICENSE
0025  *
0026  * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
0027  * All rights reserved.
0028  *
0029  * Redistribution and use in source and binary forms, with or without
0030  * modification, are permitted provided that the following conditions
0031  * are met:
0032  *
0033  *   * Redistributions of source code must retain the above copyright
0034  *     notice, this list of conditions and the following disclaimer.
0035  *   * Redistributions in binary form must reproduce the above copyright
0036  *     notice, this list of conditions and the following disclaimer in
0037  *     the documentation and/or other materials provided with the
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0040  *     contributors may be used to endorse or promote products derived
0041  *     from this software without specific prior written permission.
0042  *
0043  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
0044  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
0045  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
0046  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
0047  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
0048  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
0049  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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0053  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
0054  */
0055
0056 #ifndef _SCIC_SDS_REMOTE_NODE_TABLE_H_
0057 #define _SCIC_SDS_REMOTE_NODE_TABLE_H_
0058
0059 #include "isci.h"
0060
0061 /**
0062  *
0063  *
0064  * Remote node sets are sets of remote node index in the remote node table. The
0065  * SCU hardware requires that STP remote node entries take three consecutive
0066  * remote node index so the table is arranged in sets of three. The bits are
0067  * used as 0111 0111 to make a byte and the bits define the set of three remote
0068  * nodes to use as a sequence.
0069  */
0070 #define SCIC_SDS_REMOTE_NODE_SETS_PER_BYTE 2
0071
0072 /**
0073  *
0074  *
0075  * Since the remote node table is organized as DWORDS take the remote node sets
0076  * in bytes and represent them in DWORDs. The lowest ordered bits are the ones
0077  * used in case full DWORD is not being used. i.e. 0000 0000 0000 0000 0111
0078  * 0111 0111 0111 // if only a single WORD is in use in the DWORD.
0079  */
0080 #define SCIC_SDS_REMOTE_NODE_SETS_PER_DWORD \
0081     (sizeof(u32) * SCIC_SDS_REMOTE_NODE_SETS_PER_BYTE)
0082 /**
0083  *
0084  *
0085  * This is a count of the numeber of remote nodes that can be represented in a
0086  * byte
0087  */
0088 #define SCIC_SDS_REMOTE_NODES_PER_BYTE  \
0089     (SCU_STP_REMOTE_NODE_COUNT * SCIC_SDS_REMOTE_NODE_SETS_PER_BYTE)
0090
0091 /**
0092  *
0093  *
0094  * This is a count of the number of remote nodes that can be represented in a
0095  * DWROD
0096  */
0097 #define SCIC_SDS_REMOTE_NODES_PER_DWORD \
0098     (sizeof(u32) * SCIC_SDS_REMOTE_NODES_PER_BYTE)
0099
0100 /**
0101  *
0102  *
0103  * This is the number of bits in a remote node group
0104  */
0105 #define SCIC_SDS_REMOTE_NODES_BITS_PER_GROUP   4
0106
0107 #define SCIC_SDS_REMOTE_NODE_TABLE_INVALID_INDEX      (0xFFFFFFFF)
0108 #define SCIC_SDS_REMOTE_NODE_TABLE_FULL_SLOT_VALUE    (0x07)
0109 #define SCIC_SDS_REMOTE_NODE_TABLE_EMPTY_SLOT_VALUE   (0x00)
0110
0111 /**
0112  *
0113  *
0114  * Expander attached sata remote node count
0115  */
0116 #define SCU_STP_REMOTE_NODE_COUNT        3
0117
0118 /**
0119  *
0120  *
0121  * Expander or direct attached ssp remote node count
0122  */
0123 #define SCU_SSP_REMOTE_NODE_COUNT        1
0124
0125 /**
0126  *
0127  *
0128  * Direct attached STP remote node count
0129  */
0130 #define SCU_SATA_REMOTE_NODE_COUNT       1
0131
0132 /**
0133  * struct sci_remote_node_table -
0134  *
0135  *
0136  */
0137 struct sci_remote_node_table {
0138     /**
0139      * This field contains the array size in dwords
0140      */
0141     u16 available_nodes_array_size;
0142
0143     /**
0144      * This field contains the array size of the
0145      */
0146     u16 group_array_size;
0147
0148     /**
0149      * This field is the array of available remote node entries in bits.
0150      * Because of the way STP remote node data is allocated on the SCU hardware
0151      * the remote nodes must occupy three consecutive remote node context
0152      * entries.  For ease of allocation and de-allocation we have broken the
0153      * sets of three into a single nibble.  When the STP RNi is allocated all
0154      * of the bits in the nibble are cleared.  This math results in a table size
0155      * of MAX_REMOTE_NODES / CONSECUTIVE RNi ENTRIES for STP / 2 entries per byte.
0156      */
0157     u32 available_remote_nodes[
0158         (SCI_MAX_REMOTE_DEVICES / SCIC_SDS_REMOTE_NODES_PER_DWORD)
0159         + ((SCI_MAX_REMOTE_DEVICES % SCIC_SDS_REMOTE_NODES_PER_DWORD) != 0)];
0160
0161     /**
0162      * This field is the nibble selector for the above table.  There are three
0163      * possible selectors each for fast lookup when trying to find one, two or
0164      * three remote node entries.
0165      */
0166     u32 remote_node_groups[
0167         SCU_STP_REMOTE_NODE_COUNT][
0168         (SCI_MAX_REMOTE_DEVICES / (32 * SCU_STP_REMOTE_NODE_COUNT))
0169         + ((SCI_MAX_REMOTE_DEVICES % (32 * SCU_STP_REMOTE_NODE_COUNT)) != 0)];
0170
0171 };
0172
0173 /* --------------------------------------------------------------------------- */
0174
0175 void sci_remote_node_table_initialize(
0176     struct sci_remote_node_table *remote_node_table,
0177     u32 remote_node_entries);
0178
0179 u16 sci_remote_node_table_allocate_remote_node(
0180     struct sci_remote_node_table *remote_node_table,
0181     u32 remote_node_count);
0182
0183 void sci_remote_node_table_release_remote_node_index(
0184     struct sci_remote_node_table *remote_node_table,
0185     u32 remote_node_count,
0186     u16 remote_node_index);
0187
0188 #endif /* _SCIC_SDS_REMOTE_NODE_TABLE_H_ */