DMASequencer.cc revision 10472:399f35ed5cca 
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 <memory>
30
31#include "debug/RubyDma.hh"
32#include "debug/RubyStats.hh"
33#include "mem/protocol/SequencerMsg.hh"
34#include "mem/protocol/SequencerRequestType.hh"
35#include "mem/ruby/system/DMASequencer.hh"
36#include "mem/ruby/system/System.hh"
37
38DMASequencer::DMASequencer(const Params *p)
39    : RubyPort(p)
40{
41}
42
43void
44DMASequencer::init()
45{
46    RubyPort::init();
47    m_is_busy = false;
48    m_data_block_mask = ~ (~0 << RubySystem::getBlockSizeBits());
49}
50
51RequestStatus
52DMASequencer::makeRequest(PacketPtr pkt)
53{
54    if (m_is_busy) {
55        return RequestStatus_BufferFull;
56    }
57
58    uint64_t paddr = pkt->getAddr();
59    uint8_t* data =  pkt->getPtr<uint8_t>(true);
60    int len = pkt->getSize();
61    bool write = pkt->isWrite();
62
63    assert(!m_is_busy);  // only support one outstanding DMA request
64    m_is_busy = true;
65
66    active_request.start_paddr = paddr;
67    active_request.write = write;
68    active_request.data = data;
69    active_request.len = len;
70    active_request.bytes_completed = 0;
71    active_request.bytes_issued = 0;
72    active_request.pkt = pkt;
73
74    std::shared_ptr<SequencerMsg> msg =
75        std::make_shared<SequencerMsg>(clockEdge());
76    msg->getPhysicalAddress() = Address(paddr);
77    msg->getLineAddress() = line_address(msg->getPhysicalAddress());
78    msg->getType() = write ? SequencerRequestType_ST : SequencerRequestType_LD;
79    int offset = paddr & m_data_block_mask;
80
81    msg->getLen() = (offset + len) <= RubySystem::getBlockSizeBytes() ?
82        len : RubySystem::getBlockSizeBytes() - offset;
83
84    if (write && (data != NULL)) {
85        if (active_request.data != NULL) {
86            msg->getDataBlk().setData(data, offset, msg->getLen());
87        }
88    }
89
90    assert(m_mandatory_q_ptr != NULL);
91    m_mandatory_q_ptr->enqueue(msg);
92    active_request.bytes_issued += msg->getLen();
93
94    return RequestStatus_Issued;
95}
96
97void
98DMASequencer::issueNext()
99{
100    assert(m_is_busy);
101    active_request.bytes_completed = active_request.bytes_issued;
102    if (active_request.len == active_request.bytes_completed) {
103        //
104        // Must unset the busy flag before calling back the dma port because
105        // the callback may cause a previously nacked request to be reissued
106        //
107        DPRINTF(RubyDma, "DMA request completed\n");
108        m_is_busy = false;
109        ruby_hit_callback(active_request.pkt);
110        return;
111    }
112
113    std::shared_ptr<SequencerMsg> msg =
114        std::make_shared<SequencerMsg>(clockEdge());
115    msg->getPhysicalAddress() = Address(active_request.start_paddr +
116                                       active_request.bytes_completed);
117
118    assert((msg->getPhysicalAddress().getAddress() & m_data_block_mask) == 0);
119    msg->getLineAddress() = line_address(msg->getPhysicalAddress());
120
121    msg->getType() = (active_request.write ? SequencerRequestType_ST :
122                     SequencerRequestType_LD);
123
124    msg->getLen() =
125        (active_request.len -
126         active_request.bytes_completed < RubySystem::getBlockSizeBytes() ?
127         active_request.len - active_request.bytes_completed :
128         RubySystem::getBlockSizeBytes());
129
130    if (active_request.write) {
131        msg->getDataBlk().
132            setData(&active_request.data[active_request.bytes_completed],
133                    0, msg->getLen());
134        msg->getType() = SequencerRequestType_ST;
135    } else {
136        msg->getType() = SequencerRequestType_LD;
137    }
138
139    assert(m_mandatory_q_ptr != NULL);
140    m_mandatory_q_ptr->enqueue(msg);
141    active_request.bytes_issued += msg->getLen();
142    DPRINTF(RubyDma,
143            "DMA request bytes issued %d, bytes completed %d, total len %d\n",
144            active_request.bytes_issued, active_request.bytes_completed,
145            active_request.len);
146}
147
148void
149DMASequencer::dataCallback(const DataBlock & dblk)
150{
151    assert(m_is_busy);
152    int len = active_request.bytes_issued - active_request.bytes_completed;
153    int offset = 0;
154    if (active_request.bytes_completed == 0)
155        offset = active_request.start_paddr & m_data_block_mask;
156    assert(!active_request.write);
157    if (active_request.data != NULL) {
158        memcpy(&active_request.data[active_request.bytes_completed],
159               dblk.getData(offset, len), len);
160    }
161    issueNext();
162}
163
164void
165DMASequencer::ackCallback()
166{
167    issueNext();
168}
169
170void
171DMASequencer::recordRequestType(DMASequencerRequestType requestType) {
172    DPRINTF(RubyStats, "Recorded statistic: %s\n",
173            DMASequencerRequestType_to_string(requestType));
174}
175
176DMASequencer *
177DMASequencerParams::create()
178{
179    return new DMASequencer(this);
180}
181