dma_device.hh revision 9016:18093957a102 
1/*
2 * Copyright (c) 2012 ARM Limited
3 * All rights reserved.
4 *
5 * The license below extends only to copyright in the software and shall
6 * not be construed as granting a license to any other intellectual
7 * property including but not limited to intellectual property relating
8 * to a hardware implementation of the functionality of the software
9 * licensed hereunder.  You may use the software subject to the license
10 * terms below provided that you ensure that this notice is replicated
11 * unmodified and in its entirety in all distributions of the software,
12 * modified or unmodified, in source code or in binary form.
13 *
14 * Copyright (c) 2004-2005 The Regents of The University of Michigan
15 * All rights reserved.
16 *
17 * Redistribution and use in source and binary forms, with or without
18 * modification, are permitted provided that the following conditions are
19 * met: redistributions of source code must retain the above copyright
20 * notice, this list of conditions and the following disclaimer;
21 * redistributions in binary form must reproduce the above copyright
22 * notice, this list of conditions and the following disclaimer in the
23 * documentation and/or other materials provided with the distribution;
24 * neither the name of the copyright holders nor the names of its
25 * contributors may be used to endorse or promote products derived from
26 * this software without specific prior written permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
29 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
30 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
31 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
32 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
33 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
34 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
35 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
36 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
37 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
38 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
39 *
40 * Authors: Ali Saidi
41 *          Nathan Binkert
42 */
43
44#ifndef __DEV_DMA_DEVICE_HH__
45#define __DEV_DMA_DEVICE_HH__
46
47#include "dev/io_device.hh"
48#include "params/DmaDevice.hh"
49
50class DmaPort : public MasterPort
51{
52  protected:
53    struct DmaReqState : public Packet::SenderState, public FastAlloc
54    {
55        /** Event to call on the device when this transaction (all packets)
56         * complete. */
57        Event *completionEvent;
58
59        /** Total number of bytes that this transaction involves. */
60        Addr totBytes;
61
62        /** Number of bytes that have been acked for this transaction. */
63        Addr numBytes;
64
65        /** Amount to delay completion of dma by */
66        Tick delay;
67
68        DmaReqState(Event *ce, Addr tb, Tick _delay)
69            : completionEvent(ce), totBytes(tb), numBytes(0), delay(_delay)
70        {}
71    };
72
73    MemObject *device;
74    std::list<PacketPtr> transmitList;
75
76    /** The system that device/port are in. This is used to select which mode
77     * we are currently operating in. */
78    System *sys;
79
80    /** Id for all requests */
81    MasterID masterId;
82
83    /** Number of outstanding packets the dma port has. */
84    int pendingCount;
85
86    /** If a dmaAction is in progress. */
87    int actionInProgress;
88
89    /** If we need to drain, keep the drain event around until we're done
90     * here.*/
91    Event *drainEvent;
92
93    /** time to wait between sending another packet, increases as NACKs are
94     * recived, decreases as responses are recived. */
95    Tick backoffTime;
96
97    /** Minimum time that device should back off for after failed sendTiming */
98    Tick minBackoffDelay;
99
100    /** Maximum time that device should back off for after failed sendTiming */
101    Tick maxBackoffDelay;
102
103    /** If the port is currently waiting for a retry before it can send whatever
104     * it is that it's sending. */
105    bool inRetry;
106
107    virtual bool recvTimingResp(PacketPtr pkt);
108
109    virtual void recvRetry() ;
110
111    void queueDma(PacketPtr pkt, bool front = false);
112    void sendDma();
113
114    /** event to give us a kick every time we backoff time is reached. */
115    EventWrapper<DmaPort, &DmaPort::sendDma> backoffEvent;
116
117  public:
118    DmaPort(MemObject *dev, System *s, Tick min_backoff, Tick max_backoff);
119
120    void dmaAction(Packet::Command cmd, Addr addr, int size, Event *event,
121                   uint8_t *data, Tick delay, Request::Flags flag = 0);
122
123    bool dmaPending() { return pendingCount > 0; }
124
125    unsigned cacheBlockSize() const { return peerBlockSize(); }
126    unsigned int drain(Event *de);
127};
128
129class DmaDevice : public PioDevice
130{
131   protected:
132    DmaPort dmaPort;
133
134  public:
135    typedef DmaDeviceParams Params;
136    DmaDevice(const Params *p);
137    virtual ~DmaDevice();
138
139    const Params *
140    params() const
141    {
142        return dynamic_cast<const Params *>(_params);
143    }
144
145    void dmaWrite(Addr addr, int size, Event *event, uint8_t *data,
146                  Tick delay = 0)
147    {
148        dmaPort.dmaAction(MemCmd::WriteReq, addr, size, event, data, delay);
149    }
150
151    void dmaRead(Addr addr, int size, Event *event, uint8_t *data,
152                 Tick delay = 0)
153    {
154        dmaPort.dmaAction(MemCmd::ReadReq, addr, size, event, data, delay);
155    }
156
157    bool dmaPending() { return dmaPort.dmaPending(); }
158
159    virtual void init();
160
161    virtual unsigned int drain(Event *de);
162
163    unsigned cacheBlockSize() const { return dmaPort.cacheBlockSize(); }
164
165    virtual MasterPort &getMasterPort(const std::string &if_name,
166                                      int idx = -1);
167
168    friend class DmaPort;
169};
170
171#endif // __DEV_DMA_DEVICE_HH__
172