DMASequencer.cc revision 10231:cb2e6950956d 
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/system/DMASequencer.hh"
34#include "mem/ruby/system/System.hh"
35
36DMASequencer::DMASequencer(const Params *p)
37    : RubyPort(p)
38{
39}
40
41void
42DMASequencer::init()
43{
44    RubyPort::init();
45    m_is_busy = false;
46    m_data_block_mask = ~ (~0 << RubySystem::getBlockSizeBits());
47}
48
49RequestStatus
50DMASequencer::makeRequest(PacketPtr pkt)
51{
52    if (m_is_busy) {
53        return RequestStatus_BufferFull;
54    }
55
56    uint64_t paddr = pkt->getAddr();
57    uint8_t* data =  pkt->getPtr<uint8_t>(true);
58    int len = pkt->getSize();
59    bool write = pkt->isWrite();
60
61    assert(!m_is_busy);  // only support one outstanding DMA request
62    m_is_busy = true;
63
64    active_request.start_paddr = paddr;
65    active_request.write = write;
66    active_request.data = data;
67    active_request.len = len;
68    active_request.bytes_completed = 0;
69    active_request.bytes_issued = 0;
70    active_request.pkt = pkt;
71
72    SequencerMsg *msg = new SequencerMsg(clockEdge());
73    msg->getPhysicalAddress() = Address(paddr);
74    msg->getLineAddress() = line_address(msg->getPhysicalAddress());
75    msg->getType() = write ? SequencerRequestType_ST : SequencerRequestType_LD;
76    int offset = paddr & m_data_block_mask;
77
78    msg->getLen() = (offset + len) <= RubySystem::getBlockSizeBytes() ?
79        len : RubySystem::getBlockSizeBytes() - offset;
80
81    if (write && (data != NULL)) {
82        if (active_request.data != NULL) {
83            msg->getDataBlk().setData(data, offset, msg->getLen());
84        }
85    }
86
87    assert(m_mandatory_q_ptr != NULL);
88    m_mandatory_q_ptr->enqueue(msg);
89    active_request.bytes_issued += msg->getLen();
90
91    return RequestStatus_Issued;
92}
93
94void
95DMASequencer::issueNext()
96{
97    assert(m_is_busy);
98    active_request.bytes_completed = active_request.bytes_issued;
99    if (active_request.len == active_request.bytes_completed) {
100        //
101        // Must unset the busy flag before calling back the dma port because
102        // the callback may cause a previously nacked request to be reissued
103        //
104        DPRINTF(RubyDma, "DMA request completed\n");
105        m_is_busy = false;
106        ruby_hit_callback(active_request.pkt);
107        return;
108    }
109
110    SequencerMsg *msg = new SequencerMsg(clockEdge());
111    msg->getPhysicalAddress() = Address(active_request.start_paddr +
112                                       active_request.bytes_completed);
113
114    assert((msg->getPhysicalAddress().getAddress() & m_data_block_mask) == 0);
115    msg->getLineAddress() = line_address(msg->getPhysicalAddress());
116
117    msg->getType() = (active_request.write ? SequencerRequestType_ST :
118                     SequencerRequestType_LD);
119
120    msg->getLen() =
121        (active_request.len -
122         active_request.bytes_completed < RubySystem::getBlockSizeBytes() ?
123         active_request.len - active_request.bytes_completed :
124         RubySystem::getBlockSizeBytes());
125
126    if (active_request.write) {
127        msg->getDataBlk().
128            setData(&active_request.data[active_request.bytes_completed],
129                    0, msg->getLen());
130        msg->getType() = SequencerRequestType_ST;
131    } else {
132        msg->getType() = SequencerRequestType_LD;
133    }
134
135    assert(m_mandatory_q_ptr != NULL);
136    m_mandatory_q_ptr->enqueue(msg);
137    active_request.bytes_issued += msg->getLen();
138    DPRINTF(RubyDma,
139            "DMA request bytes issued %d, bytes completed %d, total len %d\n",
140            active_request.bytes_issued, active_request.bytes_completed,
141            active_request.len);
142}
143
144void
145DMASequencer::dataCallback(const DataBlock & dblk)
146{
147    assert(m_is_busy);
148    int len = active_request.bytes_issued - active_request.bytes_completed;
149    int offset = 0;
150    if (active_request.bytes_completed == 0)
151        offset = active_request.start_paddr & m_data_block_mask;
152    assert(!active_request.write);
153    if (active_request.data != NULL) {
154        memcpy(&active_request.data[active_request.bytes_completed],
155               dblk.getData(offset, len), len);
156    }
157    issueNext();
158}
159
160void
161DMASequencer::ackCallback()
162{
163    issueNext();
164}
165
166void
167DMASequencer::recordRequestType(DMASequencerRequestType requestType) {
168    DPRINTF(RubyStats, "Recorded statistic: %s\n",
169            DMASequencerRequestType_to_string(requestType));
170}
171
172DMASequencer *
173DMASequencerParams::create()
174{
175    return new DMASequencer(this);
176}
177