src/dev/arm/rtc_pl031.hh

   1 /*
   2  * Copyright (c) 2010-2012 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  * 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: Ali Saidi
  38  */
  39
  40 #ifndef __DEV_ARM_RTC_PL310_HH__
  41 #define __DEV_ARM_RTC_PL310_HH__
  42
  43 #include "dev/arm/amba_device.hh"
  44 #include "params/PL031.hh"
  45
  46 /** @file
  47  * This implements the ARM Primecell 031 RTC
  48  */
  49
  50 class PL031 : public AmbaIntDevice
  51 {
  52   protected:
  53     enum {
  54         DataReg    = 0x00,
  55         MatchReg   = 0x04,
  56         LoadReg    = 0x08,
  57         ControlReg = 0x0C,
  58         IntMask    = 0x10,
  59         RawISR     = 0x14,
  60         MaskedISR  = 0x18,
  61         IntClear   = 0x1C,
  62     };
  63
  64     /* Seconds since epoch that correspond to time simulation was started at the
  65      * begining of simulation and is then updated if ever written. */
  66     uint32_t timeVal;
  67
  68     /* Time when the timeVal register was written */
  69     Tick lastWrittenTick;
  70
  71     /* Previous load value */
  72     uint32_t loadVal;
  73
  74     /* RTC Match Value
  75      * Cause an interrupt when this value hits counter
  76      */
  77     uint32_t matchVal;
  78
  79     /** If timer has caused an interrupt. This is irrespective of
  80      * interrupt enable */
  81     bool rawInt;
  82
  83     /** If the timer interrupt mask that is anded with the raw interrupt to
  84      * generate a pending interrupt
  85      */
  86     bool maskInt;
  87
  88     /** If an interrupt is currently pending. Logical and of CTRL.intEnable
  89      * and rawInt */
  90     bool pendingInt;
  91
  92     /** Called when the counter reaches matches */
  93     void counterMatch();
  94     EventFunctionWrapper matchEvent;
  95
  96     /** Called to update the matchEvent when the load Value or match value are
  97      * written.
  98      */
  99     void resyncMatch();
 100
 101   public:
 102     typedef PL031Params Params;
 103     const Params *
 104     params() const
 105     {
 106         return dynamic_cast<const Params *>(_params);
 107     }
 108     /**
 109       * The constructor for RealView just registers itself with the MMU.
 110       * @param p params structure
 111       */
 112     PL031(Params *p);
 113
 114     /**
 115      * Handle a read to the device
 116      * @param pkt The memory request.
 117      * @param data Where to put the data.
 118      */
 119     Tick read(PacketPtr pkt) override;
 120
 121     /**
 122      * Handle writes to the device
 123      * @param pkt The memory request.
 124      * @param data the data
 125      */
 126     Tick write(PacketPtr pkt) override;
 127
 128     void serialize(CheckpointOut &cp) const override;
 129     void unserialize(CheckpointIn &cp) override;
 130 };
 131
 132
 133 #endif // __DEV_ARM_RTC_PL031_HH__
 134