dev/tsunami_io.hh

   1 /*
   2  * Copyright (c) 2004 The Regents of The University of Michigan
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are
   7  * met: redistributions of source code must retain the above copyright
   8  * notice, this list of conditions and the following disclaimer;
   9  * redistributions in binary form must reproduce the above copyright
  10  * notice, this list of conditions and the following disclaimer in the
  11  * documentation and/or other materials provided with the distribution;
  12  * neither the name of the copyright holders nor the names of its
  13  * contributors may be used to endorse or promote products derived from
  14  * this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  17  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  18  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  19  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  20  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  21  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  22  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  26  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 /* @file
  30  * Tsunami Fake I/O Space mapping including RTC/timer interrupts
  31  */
  32
  33 #ifndef __TSUNAMI_DMA_HH__
  34 #define __TSUNAMI_DMA_HH__
  35
  36 #include "dev/io_device.hh"
  37 #include "base/range.hh"
  38 #include "dev/tsunami.hh"
  39 #include "sim/eventq.hh"
  40
  41 /** How often the RTC interrupts */
  42 static const int RTC_RATE  = 1024;
  43
  44 /*
  45  * Tsunami I/O device is a catch all for all the south bridge stuff we care
  46  * to implement.
  47  */
  48 class TsunamiIO : public PioDevice
  49 {
  50   private:
  51     /** The base address of this device */
  52     Addr addr;
  53
  54     /** The size of mappad from the above address */
  55     static const Addr size = 0xff;
  56
  57     struct tm tm;
  58
  59     /** In Tsunami RTC only has two i/o ports one for data and one for address,
  60      * so you write the address and then read/write the data. This store the
  61      * address you are going to be reading from on a read.
  62      */
  63     uint8_t RTCAddress;
  64
  65   protected:
  66
  67     /**
  68      * The ClockEvent is handles the PIT interrupts
  69      */
  70     class ClockEvent : public Event
  71     {
  72       protected:
  73         /** how often the PIT fires */
  74         Tick interval;
  75         /** The mode of the PIT */
  76         uint8_t mode;
  77         /** The status of the PIT */
  78         uint8_t status;
  79
  80       public:
  81         /**
  82          * Just set the mode to 0
  83          */
  84         ClockEvent();
  85
  86         /**
  87          * processs the timer event
  88          */
  89         virtual void process();
  90
  91         /**
  92          * Returns a description of this event
  93          * @return the description
  94          */
  95         virtual const char *description();
  96
  97         /**
  98          * Schedule a timer interrupt to occur sometime in the future.
  99          */
 100         void Program(int count);
 101
 102         /**
 103          * Write the mode bits of the PIT.
 104          * @param mode the new mode
 105          */
 106         void ChangeMode(uint8_t mode);
 107
 108         /**
 109          * The current PIT status.
 110          * @return the status of the PIT
 111          */
 112         uint8_t Status();
 113
 114         /**
 115          * Serialize this object to the given output stream.
 116          * @param os The stream to serialize to.
 117          */
 118         virtual void serialize(std::ostream &os);
 119
 120
 121         /**
 122          * Reconstruct the state of this object from a checkpoint.
 123          * @param cp The checkpoint use.
 124          * @param section The section name of this object
 125          */
 126         virtual void unserialize(Checkpoint *cp, const std::string &section);
 127      };
 128
 129     /**
 130      * Process RTC timer events and generate interrupts appropriately.
 131      */
 132     class RTCEvent : public Event
 133     {
 134       protected:
 135           /** A pointer back to tsunami to create interrupt the processor. */
 136           Tsunami* tsunami;
 137       public:
 138           /** RTC Event initializes the RTC event by scheduling an event
 139            * RTC_RATE times pre second. */
 140           RTCEvent(Tsunami* t);
 141
 142           /**
 143            * Interrupth the processor and reschedule the event.
 144            * */
 145           virtual void process();
 146
 147           /**
 148            * Return a description of this event.
 149            * @return a description
 150            */
 151           virtual const char *description();
 152
 153           /**
 154            * Serialize this object to the given output stream.
 155            * @param os The stream to serialize to.
 156            */
 157           virtual void serialize(std::ostream &os);
 158
 159
 160           /**
 161            * Reconstruct the state of this object from a checkpoint.
 162            * @param cp The checkpoint use.
 163            * @param section The section name of this object
 164            */
 165           virtual void unserialize(Checkpoint *cp, const std::string &section);
 166      };
 167
 168     /** uip UpdateInProgess says that the rtc is updating, but we just fake it
 169      * by alternating it on every read of the bit since we are going to
 170      * override the loop_per_jiffy time that it is trying to use the UIP to
 171      * calculate.
 172      */
 173     uint8_t uip;
 174
 175     /** Mask of the PIC1 */
 176     uint8_t mask1;
 177
 178     /** Mask of the PIC2 */
 179     uint8_t mask2;
 180
 181     /** Mode of PIC1. Not used for anything */
 182     uint8_t mode1;
 183
 184     /** Mode of PIC2. Not used for anything */
 185     uint8_t mode2;
 186
 187     /** Raw PIC interrupt register before masking */
 188     uint8_t picr; //Raw PIC interrput register
 189
 190     /** Is the pic interrupting right now or not. */
 191     bool picInterrupting;
 192
 193     /** A pointer to the Tsunami device which be belong to */
 194     Tsunami *tsunami;
 195
 196     /**
 197      * This timer is initilized, but after I wrote the code
 198      * it doesn't seem to be used again, and best I can tell
 199      * it too is not connected to any interrupt port
 200      */
 201     ClockEvent timer0;
 202
 203     /**
 204      * This timer is used to control the speaker, which
 205      * we normally could care less about, however it is
 206      * also used to calculated the clockspeed and hense
 207      * bogomips which is kinda important to the scheduler
 208      * so we need to implemnt it although after boot I can't
 209      * imagine we would be playing with the PC speaker much
 210      */
 211     ClockEvent timer2;
 212
 213     /** This is the event used to interrupt the cpu like an RTC.  */
 214     RTCEvent rtc;
 215
 216     /** The interval is set via two writes to the PIT.
 217      * This variable contains a flag as to how many writes have happened, and
 218      * the time so far.
 219      */
 220     uint32_t timerData;
 221
 222
 223   public:
 224     /**
 225      * Return the freqency of the RTC
 226      * @return interrupt rate of the RTC
 227      */
 228     Tick  frequency() const { return RTC_RATE; }
 229
 230
 231     /**
 232      * Initialize all the data for devices supported by Tsunami I/O.
 233      * @param name name of this device.
 234      * @param t pointer back to the Tsunami object that we belong to.
 235      * @param init_time Time (as in seconds since 1970) to set RTC to.
 236      * @param a address we are mapped at.
 237      * @param mmu pointer to the memory controller that sends us events.
 238      */
 239     TsunamiIO(const std::string &name, Tsunami *t, time_t init_time,
 240               Addr a, MemoryController *mmu, HierParams *hier, Bus *bus,
 241               Tick pio_latency);
 242
 243     /**
 244      * Create the tm struct from seconds since 1970
 245      */
 246     void set_time(time_t t);
 247
 248     /**
 249       * Process a read to one of the devices we are emulating.
 250       * @param req Contains the address to read from.
 251       * @param data A pointer to write the read data to.
 252       * @return The fault condition of the access.
 253       */
 254     virtual Fault read(MemReqPtr &req, uint8_t *data);
 255
 256     /**
 257       * Process a write to one of the devices we emulate.
 258       * @param req Contains the address to write to.
 259       * @param data The data to write.
 260       * @return The fault condition of the access.
 261       */
 262     virtual Fault write(MemReqPtr &req, const uint8_t *data);
 263
 264     /**
 265      * Post an PIC interrupt to the CPU via the CChip
 266      * @param bitvector interrupt to post.
 267      */
 268     void postPIC(uint8_t bitvector);
 269
 270     /**
 271      * Clear a posted interrupt
 272      * @param bitvector interrupt to clear
 273      */
 274     void clearPIC(uint8_t bitvector);
 275
 276     /**
 277      * Serialize this object to the given output stream.
 278      * @param os The stream to serialize to.
 279      */
 280     virtual void serialize(std::ostream &os);
 281
 282
 283     /**
 284      * Reconstruct the state of this object from a checkpoint.
 285      * @param cp The checkpoint use.
 286      * @param section The section name of this object
 287      */
 288     virtual void unserialize(Checkpoint *cp, const std::string &section);
 289
 290
 291     Tick cacheAccess(MemReqPtr &req);
 292 };
 293
 294 #endif // __TSUNAMI_IO_HH__