DMASequencer.cc revision 9104:27d56b644e78 
1/*
2 * Copyright (c) 2008 Mark D. Hill and David A. Wood
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met: redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer;
9 * redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution;
12 * neither the name of the copyright holders nor the names of its
13 * contributors may be used to endorse or promote products derived from
14 * this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#include "debug/RubyDma.hh"
30#include "debug/RubyStats.hh"
31#include "mem/protocol/SequencerMsg.hh"
32#include "mem/protocol/SequencerRequestType.hh"
33#include "mem/ruby/buffers/MessageBuffer.hh"
34#include "mem/ruby/system/DMASequencer.hh"
35#include "mem/ruby/system/System.hh"
36
37DMASequencer::DMASequencer(const Params *p)
38    : RubyPort(p)
39{
40}
41
42void
43DMASequencer::init()
44{
45    RubyPort::init();
46    m_is_busy = false;
47    m_data_block_mask = ~ (~0 << RubySystem::getBlockSizeBits());
48}
49
50RequestStatus
51DMASequencer::makeRequest(PacketPtr pkt)
52{
53    if (m_is_busy) {
54        return RequestStatus_BufferFull;
55    }
56
57    uint64_t paddr = pkt->getAddr();
58    uint8_t* data =  pkt->getPtr<uint8_t>(true);
59    int len = pkt->getSize();
60    bool write = pkt->isWrite();
61
62    assert(!m_is_busy);  // only support one outstanding DMA request
63    m_is_busy = true;
64
65    active_request.start_paddr = paddr;
66    active_request.write = write;
67    active_request.data = data;
68    active_request.len = len;
69    active_request.bytes_completed = 0;
70    active_request.bytes_issued = 0;
71    active_request.pkt = pkt;
72
73    SequencerMsg *msg = new SequencerMsg;
74    msg->getPhysicalAddress() = Address(paddr);
75    msg->getLineAddress() = line_address(msg->getPhysicalAddress());
76    msg->getType() = write ? SequencerRequestType_ST : SequencerRequestType_LD;
77    int offset = paddr & m_data_block_mask;
78
79    msg->getLen() = (offset + len) <= RubySystem::getBlockSizeBytes() ?
80        len : RubySystem::getBlockSizeBytes() - offset;
81
82    if (write && (data != NULL)) {
83        if (active_request.data != NULL) {
84            msg->getDataBlk().setData(data, offset, msg->getLen());
85        }
86    }
87
88    assert(m_mandatory_q_ptr != NULL);
89    m_mandatory_q_ptr->enqueue(msg);
90    active_request.bytes_issued += msg->getLen();
91
92    return RequestStatus_Issued;
93}
94
95void
96DMASequencer::issueNext()
97{
98    assert(m_is_busy == true);
99    active_request.bytes_completed = active_request.bytes_issued;
100    if (active_request.len == active_request.bytes_completed) {
101        //
102        // Must unset the busy flag before calling back the dma port because
103        // the callback may cause a previously nacked request to be reissued
104        //
105        DPRINTF(RubyDma, "DMA request completed\n");
106        m_is_busy = false;
107        ruby_hit_callback(active_request.pkt);
108        return;
109    }
110
111    SequencerMsg *msg = new SequencerMsg;
112    msg->getPhysicalAddress() = Address(active_request.start_paddr +
113                                       active_request.bytes_completed);
114
115    assert((msg->getPhysicalAddress().getAddress() & m_data_block_mask) == 0);
116    msg->getLineAddress() = line_address(msg->getPhysicalAddress());
117
118    msg->getType() = (active_request.write ? SequencerRequestType_ST :
119                     SequencerRequestType_LD);
120
121    msg->getLen() =
122        (active_request.len -
123         active_request.bytes_completed < RubySystem::getBlockSizeBytes() ?
124         active_request.len - active_request.bytes_completed :
125         RubySystem::getBlockSizeBytes());
126
127    if (active_request.write) {
128        msg->getDataBlk().
129            setData(&active_request.data[active_request.bytes_completed],
130                    0, msg->getLen());
131        msg->getType() = SequencerRequestType_ST;
132    } else {
133        msg->getType() = SequencerRequestType_LD;
134    }
135
136    assert(m_mandatory_q_ptr != NULL);
137    m_mandatory_q_ptr->enqueue(msg);
138    active_request.bytes_issued += msg->getLen();
139    DPRINTF(RubyDma,
140            "DMA request bytes issued %d, bytes completed %d, total len %d\n",
141            active_request.bytes_issued, active_request.bytes_completed,
142            active_request.len);
143}
144
145void
146DMASequencer::dataCallback(const DataBlock & dblk)
147{
148    assert(m_is_busy == true);
149    int len = active_request.bytes_issued - active_request.bytes_completed;
150    int offset = 0;
151    if (active_request.bytes_completed == 0)
152        offset = active_request.start_paddr & m_data_block_mask;
153    assert(active_request.write == false);
154    if (active_request.data != NULL) {
155        memcpy(&active_request.data[active_request.bytes_completed],
156               dblk.getData(offset, len), len);
157    }
158    issueNext();
159}
160
161void
162DMASequencer::ackCallback()
163{
164    issueNext();
165}
166
167void
168DMASequencer::printConfig(std::ostream & out)
169{
170}
171
172void
173DMASequencer::recordRequestType(DMASequencerRequestType requestType) {
174    DPRINTF(RubyStats, "Recorded statistic: %s\n",
175            DMASequencerRequestType_to_string(requestType));
176}
177
178DMASequencer *
179DMASequencerParams::create()
180{
181    return new DMASequencer(this);
182}
183