dma_device.hh revision 9133:82491f9ed266 
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
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 we need to drain, keep the drain event around until we're done
87     * here.*/
88    Event *drainEvent;
89
90    /** time to wait between sending another packet, increases as NACKs are
91     * recived, decreases as responses are recived. */
92    Tick backoffTime;
93
94    /** Minimum time that device should back off for after failed sendTiming */
95    Tick minBackoffDelay;
96
97    /** Maximum time that device should back off for after failed sendTiming */
98    Tick maxBackoffDelay;
99
100    /** If the port is currently waiting for a retry before it can send whatever
101     * it is that it's sending. */
102    bool inRetry;
103
104    virtual bool recvTimingResp(PacketPtr pkt);
105
106    virtual void recvRetry() ;
107
108    void queueDma(PacketPtr pkt, bool front = false);
109    void sendDma();
110
111    /** event to give us a kick every time we backoff time is reached. */
112    EventWrapper<DmaPort, &DmaPort::sendDma> backoffEvent;
113
114  public:
115    DmaPort(MemObject *dev, System *s, Tick min_backoff, Tick max_backoff);
116
117    void dmaAction(Packet::Command cmd, Addr addr, int size, Event *event,
118                   uint8_t *data, Tick delay, Request::Flags flag = 0);
119
120    bool dmaPending() { return pendingCount > 0; }
121
122    unsigned cacheBlockSize() const { return peerBlockSize(); }
123    unsigned int drain(Event *de);
124};
125
126class DmaDevice : public PioDevice
127{
128   protected:
129    DmaPort dmaPort;
130
131  public:
132    typedef DmaDeviceParams Params;
133    DmaDevice(const Params *p);
134    virtual ~DmaDevice();
135
136    const Params *
137    params() const
138    {
139        return dynamic_cast<const Params *>(_params);
140    }
141
142    void dmaWrite(Addr addr, int size, Event *event, uint8_t *data,
143                  Tick delay = 0)
144    {
145        dmaPort.dmaAction(MemCmd::WriteReq, addr, size, event, data, delay);
146    }
147
148    void dmaRead(Addr addr, int size, Event *event, uint8_t *data,
149                 Tick delay = 0)
150    {
151        dmaPort.dmaAction(MemCmd::ReadReq, addr, size, event, data, delay);
152    }
153
154    bool dmaPending() { return dmaPort.dmaPending(); }
155
156    virtual void init();
157
158    virtual unsigned int drain(Event *de);
159
160    unsigned cacheBlockSize() const { return dmaPort.cacheBlockSize(); }
161
162    virtual MasterPort &getMasterPort(const std::string &if_name,
163                                      int idx = -1);
164
165    friend class DmaPort;
166};
167
168#endif // __DEV_DMA_DEVICE_HH__
169