1/*
2 * Copyright (c) 2011-2013, 2018 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 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions are
16 * met: redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer;
18 * redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution;
21 * neither the name of the copyright holders nor the names of its
22 * contributors may be used to endorse or promote products derived from
23 * this software without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
26 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
27 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
28 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
29 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
30 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
31 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
35 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36 *
37 * Authors: Andreas Hansson
38 */
39
40/**
41 * @file
42 * PortProxy Object Declaration.
43 *
44 * Port proxies are used when non-structural entities need access to
45 * the memory system (or structural entities that want to peak into
46 * the memory system without making a real memory access).
47 *
48 * Proxy objects replace the previous FunctionalPort, TranslatingPort
49 * and VirtualPort objects, which provided the same functionality as
50 * the proxies, but were instances of ports not corresponding to real
51 * structural ports of the simulated system. Via the port proxies all
52 * the accesses go through an actual port (either the system port,
53 * e.g. for processes or initialisation, or a the data port of the
54 * CPU, e.g. for threads) and thus are transparent to a potentially
55 * distributed memory and automatically adhere to the memory map of
56 * the system.
57 */
58
59#ifndef __MEM_PORT_PROXY_HH__
60#define __MEM_PORT_PROXY_HH__
61
62#include <functional>
63#include <limits>
64
65#include "mem/port.hh"
66#include "sim/byteswap.hh"
67
68/**
69 * This object is a proxy for a port or other object which implements the
70 * functional response protocol, to be used for debug accesses.
71 *
72 * This proxy object is used when non structural entities
73 * (e.g. thread contexts, object file loaders) need access to the
74 * memory system. It calls the corresponding functions on the underlying
75 * protocol, and provides templatized convenience access functions.
76 *
77 * The addresses are interpreted as physical addresses.
78 *
79 * @sa SETranslatingProxy
80 * @sa FSTranslatingProxy
81 */
82class PortProxy : FunctionalRequestProtocol
83{
84  public:
85    typedef std::function<void(PacketPtr pkt)> SendFunctionalFunc;
86
87  private:
88    SendFunctionalFunc sendFunctional;
89
90    /** Granularity of any transactions issued through this proxy. */
91    const unsigned int _cacheLineSize;
92
93    void
94    recvFunctionalSnoop(PacketPtr pkt) override
95    {
96        // Since port proxies aren't anyone else's peer, they should never
97        // receive snoops.
98        panic("Port proxies should never receive snoops.");
99    }
100
101  public:
102    PortProxy(SendFunctionalFunc func, unsigned int cacheLineSize) :
103        sendFunctional(func), _cacheLineSize(cacheLineSize)
104    {}
105    PortProxy(const MasterPort &port, unsigned int cacheLineSize) :
106        sendFunctional([&port](PacketPtr pkt)->void {
107                port.sendFunctional(pkt);
108            }), _cacheLineSize(cacheLineSize)
109    {}
110    virtual ~PortProxy() { }
111
112
113
114    /** Fixed functionality for use in base classes. */
115
116    /**
117     * Read size bytes memory at physical address and store in p.
118     */
119    void readBlobPhys(Addr addr, Request::Flags flags,
120                      void *p, int size) const;
121
122    /**
123     * Write size bytes from p to physical address.
124     */
125    void writeBlobPhys(Addr addr, Request::Flags flags,
126                       const void *p, int size) const;
127
128    /**
129     * Fill size bytes starting at physical addr with byte value val.
130     */
131    void memsetBlobPhys(Addr addr, Request::Flags flags,
132                        uint8_t v, int size) const;
133
134
135
136    /** Methods to override in base classes */
137
138    /**
139     * Read size bytes memory at address and store in p.
140     * Returns true on success and false on failure.
141     */
142    virtual bool
143    tryReadBlob(Addr addr, void *p, int size) const
144    {
145        readBlobPhys(addr, 0, p, size);
146        return true;
147    }
148
149    /**
150     * Write size bytes from p to address.
151     * Returns true on success and false on failure.
152     */
153    virtual bool
154    tryWriteBlob(Addr addr, const void *p, int size) const
155    {
156        writeBlobPhys(addr, 0, p, size);
157        return true;
158    }
159
160    /**
161     * Fill size bytes starting at addr with byte value val.
162     * Returns true on success and false on failure.
163     */
164    virtual bool
165    tryMemsetBlob(Addr addr, uint8_t val, int size) const
166    {
167        memsetBlobPhys(addr, 0, val, size);
168        return true;
169    }
170
171
172
173    /** Higher level interfaces based on the above. */
174
175    /**
176     * Same as tryReadBlob, but insists on success.
177     */
178    void
179    readBlob(Addr addr, void *p, int size) const
180    {
181        if (!tryReadBlob(addr, p, size))
182            fatal("readBlob(%#x, ...) failed", addr);
183    }
184
185    /**
186     * Same as tryWriteBlob, but insists on success.
187     */
188    void
189    writeBlob(Addr addr, const void *p, int size) const
190    {
191        if (!tryWriteBlob(addr, p, size))
192            fatal("writeBlob(%#x, ...) failed", addr);
193    }
194
195    /**
196     * Same as tryMemsetBlob, but insists on success.
197     */
198    void
199    memsetBlob(Addr addr, uint8_t v, int size) const
200    {
201        if (!tryMemsetBlob(addr, v, size))
202            fatal("memsetBlob(%#x, ...) failed", addr);
203    }
204
205    /**
206     * Read sizeof(T) bytes from address and return as object T.
207     */
208    template <typename T>
209    T read(Addr address) const;
210
211    /**
212     * Write object T to address. Writes sizeof(T) bytes.
213     */
214    template <typename T>
215    void write(Addr address, const T &data) const;
216
217    /**
218     * Read sizeof(T) bytes from address and return as object T.
219     * Performs endianness conversion from the selected guest to host order.
220     */
221    template <typename T>
222    T read(Addr address, ByteOrder guest_byte_order) const;
223
224    /**
225     * Write object T to address. Writes sizeof(T) bytes.
226     * Performs endianness conversion from host to the selected guest order.
227     */
228    template <typename T>
229    void write(Addr address, T data, ByteOrder guest_byte_order) const;
230
231    /**
232     * Write the string str into guest memory at address addr.
233     * Returns true on success and false on failure.
234     */
235    bool tryWriteString(Addr addr, const char *str) const;
236
237    /**
238     * Same as tryWriteString, but insists on success.
239     */
240    void
241    writeString(Addr addr, const char *str) const
242    {
243        if (!tryWriteString(addr, str))
244            fatal("writeString(%#x, ...) failed", addr);
245    }
246
247    /**
248     * Reads the string at guest address addr into the std::string str.
249     * Returns true on success and false on failure.
250     */
251    bool tryReadString(std::string &str, Addr addr) const;
252
253    /**
254     * Same as tryReadString, but insists on success.
255     */
256    void
257    readString(std::string &str, Addr addr) const
258    {
259        if (!tryReadString(str, addr))
260            fatal("readString(%#x, ...) failed", addr);
261    }
262
263    /**
264     * Reads the string at guest address addr into the char * str, reading up
265     * to maxlen characters. The last character read is always a nul
266     * terminator. Returns true on success and false on failure.
267     */
268    bool tryReadString(char *str, Addr addr, size_t maxlen) const;
269
270    /**
271     * Same as tryReadString, but insists on success.
272     */
273    void
274    readString(char *str, Addr addr, size_t maxlen) const
275    {
276        if (!tryReadString(str, addr, maxlen))
277            fatal("readString(%#x, ...) failed", addr);
278    }
279};
280
281
282template <typename T>
283T
284PortProxy::read(Addr address) const
285{
286    T data;
287    readBlob(address, &data, sizeof(T));
288    return data;
289}
290
291template <typename T>
292void
293PortProxy::write(Addr address, const T &data) const
294{
295    writeBlob(address, &data, sizeof(T));
296}
297
298template <typename T>
299T
300PortProxy::read(Addr address, ByteOrder byte_order) const
301{
302    T data;
303    readBlob(address, &data, sizeof(T));
304    return gtoh(data, byte_order);
305}
306
307template <typename T>
308void
309PortProxy::write(Addr address, T data, ByteOrder byte_order) const
310{
311    data = htog(data, byte_order);
312    writeBlob(address, &data, sizeof(T));
313}
314
315#endif // __MEM_PORT_PROXY_HH__
316