pl011.cc revision 10565:23593fdaadcd 
1/*
2 * Copyright (c) 2010 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) 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 */
42
43#include "base/trace.hh"
44#include "debug/Checkpoint.hh"
45#include "debug/Uart.hh"
46#include "dev/arm/amba_device.hh"
47#include "dev/arm/base_gic.hh"
48#include "dev/arm/pl011.hh"
49#include "dev/terminal.hh"
50#include "mem/packet.hh"
51#include "mem/packet_access.hh"
52#include "sim/sim_exit.hh"
53
54Pl011::Pl011(const Params *p)
55    : Uart(p, 0xfff), control(0x300), fbrd(0), ibrd(0), lcrh(0), ifls(0x12),
56      imsc(0), rawInt(0), maskInt(0), intNum(p->int_num), gic(p->gic),
57      endOnEOT(p->end_on_eot), intDelay(p->int_delay), intEvent(this)
58{
59}
60
61Tick
62Pl011::read(PacketPtr pkt)
63{
64    assert(pkt->getAddr() >= pioAddr && pkt->getAddr() < pioAddr + pioSize);
65
66    Addr daddr = pkt->getAddr() - pioAddr;
67
68    DPRINTF(Uart, " read register %#x size=%d\n", daddr, pkt->getSize());
69
70    // use a temporary data since the uart registers are read/written with
71    // different size operations
72    //
73    uint32_t data = 0;
74
75    switch(daddr) {
76      case UART_DR:
77        data = 0;
78        if (term->dataAvailable())
79            data = term->in();
80        break;
81      case UART_FR:
82        // For now we're infintely fast, so TX is never full, always empty,
83        // always clear to send
84        data = UART_FR_TXFE | UART_FR_CTS;
85        if (!term->dataAvailable())
86            data |= UART_FR_RXFE;
87        DPRINTF(Uart, "Reading FR register as %#x rawInt=0x%x imsc=0x%x maskInt=0x%x\n",
88                data, rawInt, imsc, maskInt);
89        break;
90      case UART_CR:
91        data = control;
92        break;
93      case UART_IBRD:
94        data = ibrd;
95        break;
96      case UART_FBRD:
97        data = fbrd;
98        break;
99      case UART_LCRH:
100        data = lcrh;
101        break;
102      case UART_IFLS:
103        data = ifls;
104        break;
105      case UART_IMSC:
106        data = imsc;
107        break;
108      case UART_RIS:
109        data = rawInt;
110        DPRINTF(Uart, "Reading Raw Int status as 0x%x\n", rawInt);
111        break;
112      case UART_MIS:
113        DPRINTF(Uart, "Reading Masked Int status as 0x%x\n", rawInt);
114        data = maskInt;
115        break;
116      default:
117        if (readId(pkt, AMBA_ID, pioAddr)) {
118            // Hack for variable size accesses
119            data = pkt->get<uint32_t>();
120            break;
121        }
122
123        panic("Tried to read PL011 at offset %#x that doesn't exist\n", daddr);
124        break;
125    }
126
127    switch(pkt->getSize()) {
128      case 1:
129        pkt->set<uint8_t>(data);
130        break;
131      case 2:
132        pkt->set<uint16_t>(data);
133        break;
134      case 4:
135        pkt->set<uint32_t>(data);
136        break;
137      default:
138        panic("Uart read size too big?\n");
139        break;
140    }
141
142
143    pkt->makeAtomicResponse();
144    return pioDelay;
145}
146
147Tick
148Pl011::write(PacketPtr pkt)
149{
150
151    assert(pkt->getAddr() >= pioAddr && pkt->getAddr() < pioAddr + pioSize);
152
153    Addr daddr = pkt->getAddr() - pioAddr;
154
155    DPRINTF(Uart, " write register %#x value %#x size=%d\n", daddr,
156            pkt->get<uint8_t>(), pkt->getSize());
157
158    // use a temporary data since the uart registers are read/written with
159    // different size operations
160    //
161    uint32_t data = 0;
162
163    switch(pkt->getSize()) {
164      case 1:
165        data = pkt->get<uint8_t>();
166        break;
167      case 2:
168        data = pkt->get<uint16_t>();
169        break;
170      case 4:
171        data = pkt->get<uint32_t>();
172        break;
173      default:
174        panic("Uart write size too big?\n");
175        break;
176    }
177
178
179    switch (daddr) {
180        case UART_DR:
181          if ((data & 0xFF) == 0x04 && endOnEOT)
182            exitSimLoop("UART received EOT", 0);
183
184        term->out(data & 0xFF);
185
186        //raw interrupt is set regardless of imsc.txim
187        rawInt.txim = 1;
188        if (imsc.txim) {
189            DPRINTF(Uart, "TX int enabled, scheduling interruptt\n");
190            if (!intEvent.scheduled())
191                schedule(intEvent, curTick() + intDelay);
192        }
193
194        break;
195      case UART_CR:
196        control = data;
197        break;
198      case UART_IBRD:
199        ibrd = data;
200        break;
201      case UART_FBRD:
202        fbrd = data;
203        break;
204      case UART_LCRH:
205        lcrh = data;
206        break;
207      case UART_IFLS:
208        ifls = data;
209        break;
210      case UART_IMSC:
211        imsc = data;
212
213        if (imsc.feim || imsc.peim || imsc.beim || imsc.oeim || imsc.rsvd)
214            panic("Unknown interrupt enabled\n");
215
216        // rimim, ctsmim, dcdmim, dsrmim can be enabled but are ignored
217        // they are supposed to interrupt on a change of status in the line
218        // which we should never have since our terminal is happy to always
219        // receive bytes.
220
221        if (imsc.txim) {
222            DPRINTF(Uart, "Writing to IMSC: TX int enabled, scheduling interruptt\n");
223            rawInt.txim = 1;
224            if (!intEvent.scheduled())
225                schedule(intEvent, curTick() + intDelay);
226        }
227
228        break;
229
230      case UART_ICR:
231        DPRINTF(Uart, "Clearing interrupts 0x%x\n", data);
232        rawInt = rawInt & ~data;
233        maskInt = rawInt & imsc;
234
235        DPRINTF(Uart, " -- Masked interrupts 0x%x\n", maskInt);
236
237        if (!maskInt)
238            gic->clearInt(intNum);
239
240        break;
241      default:
242        panic("Tried to write PL011 at offset %#x that doesn't exist\n", daddr);
243        break;
244    }
245    pkt->makeAtomicResponse();
246    return pioDelay;
247}
248
249void
250Pl011::dataAvailable()
251{
252    /*@todo ignore the fifo, just say we have data now
253     * We might want to fix this, or we might not care */
254    rawInt.rxim = 1;
255    rawInt.rtim = 1;
256
257    DPRINTF(Uart, "Data available, scheduling interrupt\n");
258
259    if (!intEvent.scheduled())
260        schedule(intEvent, curTick() + intDelay);
261}
262
263void
264Pl011::generateInterrupt()
265{
266    DPRINTF(Uart, "Generate Interrupt: imsc=0x%x rawInt=0x%x maskInt=0x%x\n",
267            imsc, rawInt, maskInt);
268    maskInt = imsc & rawInt;
269
270    if (maskInt.rxim || maskInt.rtim || maskInt.txim) {
271        gic->sendInt(intNum);
272        DPRINTF(Uart, " -- Generated\n");
273    }
274
275}
276
277
278
279void
280Pl011::serialize(std::ostream &os)
281{
282    DPRINTF(Checkpoint, "Serializing Arm PL011\n");
283    SERIALIZE_SCALAR(control);
284    SERIALIZE_SCALAR(fbrd);
285    SERIALIZE_SCALAR(ibrd);
286    SERIALIZE_SCALAR(lcrh);
287    SERIALIZE_SCALAR(ifls);
288
289    uint16_t imsc_serial = imsc;
290    SERIALIZE_SCALAR(imsc_serial);
291
292    uint16_t rawInt_serial = rawInt;
293    SERIALIZE_SCALAR(rawInt_serial);
294
295    uint16_t maskInt_serial = maskInt;
296    SERIALIZE_SCALAR(maskInt_serial);
297
298    SERIALIZE_SCALAR(endOnEOT);
299    SERIALIZE_SCALAR(intDelay);
300}
301
302void
303Pl011::unserialize(Checkpoint *cp, const std::string &section)
304{
305    DPRINTF(Checkpoint, "Unserializing Arm PL011\n");
306
307    UNSERIALIZE_SCALAR(control);
308    UNSERIALIZE_SCALAR(fbrd);
309    UNSERIALIZE_SCALAR(ibrd);
310    UNSERIALIZE_SCALAR(lcrh);
311    UNSERIALIZE_SCALAR(ifls);
312
313    uint16_t imsc_serial;
314    UNSERIALIZE_SCALAR(imsc_serial);
315    imsc = imsc_serial;
316
317    uint16_t rawInt_serial;
318    UNSERIALIZE_SCALAR(rawInt_serial);
319    rawInt = rawInt_serial;
320
321    uint16_t maskInt_serial;
322    UNSERIALIZE_SCALAR(maskInt_serial);
323    maskInt = maskInt_serial;
324
325    UNSERIALIZE_SCALAR(endOnEOT);
326    UNSERIALIZE_SCALAR(intDelay);
327}
328
329Pl011 *
330Pl011Params::create()
331{
332    return new Pl011(this);
333}
334