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
  40 /** How often the RTC interrupts */
  41 static const int RTC_RATE  = 1024;
  42
  43 /*
  44  * Tsunami I/O device is a catch all for all the south bridge stuff we care
  45  * to implement.
  46  */
  47 class TsunamiIO : public PioDevice
  48 {
  49   private:
  50     /** The base address of this device */
  51     Addr addr;
  52
  53     /** The size of mappad from the above address */
  54     static const Addr size = 0xff;
  55
  56     struct tm tm;
  57
  58     /** In Tsunami RTC only has two i/o ports one for data and one for address,
  59      * so you write the address and then read/write the data. This store the
  60      * address you are going to be reading from on a read.
  61      */
  62     uint8_t RTCAddress;
  63
  64   protected:
  65
  66     /**
  67      * The ClockEvent is handles the PIT interrupts
  68      */
  69     class ClockEvent : public Event
  70     {
  71       protected:
  72         /** how often the PIT fires */
  73         Tick interval;
  74         /** The mode of the PIT */
  75         uint8_t mode;
  76         /** The status of the PIT */
  77         uint8_t status;
  78
  79       public:
  80         /**
  81          * Just set the mode to 0
  82          */
  83         ClockEvent();
  84
  85         /**
  86          * processs the timer event
  87          */
  88         virtual void process();
  89
  90         /**
  91          * Returns a description of this event
  92          * @return the description
  93          */
  94         virtual const char *description();
  95
  96         /**
  97          * Schedule a timer interrupt to occur sometime in the future.
  98          */
  99         void Program(int count);
 100
 101         /**
 102          * Write the mode bits of the PIT.
 103          * @param mode the new mode
 104          */
 105         void ChangeMode(uint8_t mode);
 106
 107         /**
 108          * The current PIT status.
 109          * @return the status of the PIT
 110          */
 111         uint8_t Status();
 112
 113         /**
 114          * Serialize this object to the given output stream.
 115          * @param os The stream to serialize to.
 116          */
 117         virtual void serialize(std::ostream &os);
 118
 119
 120         /**
 121          * Reconstruct the state of this object from a checkpoint.
 122          * @param cp The checkpoint use.
 123          * @param section The section name of this object
 124          */
 125         virtual void unserialize(Checkpoint *cp, const std::string &section);
 126      };
 127
 128     /**
 129      * Process RTC timer events and generate interrupts appropriately.
 130      */
 131     class RTCEvent : public Event
 132     {
 133       protected:
 134           /** A pointer back to tsunami to create interrupt the processor. */
 135           Tsunami* tsunami;
 136       public:
 137           /** RTC Event initializes the RTC event by scheduling an event
 138            * RTC_RATE times pre second. */
 139           RTCEvent(Tsunami* t);
 140
 141           /**
 142            * Interrupth the processor and reschedule the event.
 143            * */
 144           virtual void process();
 145
 146           /**
 147            * Return a description of this event.
 148            * @return a description
 149            */
 150           virtual const char *description();
 151
 152           /**
 153            * Serialize this object to the given output stream.
 154            * @param os The stream to serialize to.
 155            */
 156           virtual void serialize(std::ostream &os);
 157
 158
 159           /**
 160            * Reconstruct the state of this object from a checkpoint.
 161            * @param cp The checkpoint use.
 162            * @param section The section name of this object
 163            */
 164           virtual void unserialize(Checkpoint *cp, const std::string &section);
 165      };
 166
 167     /** uip UpdateInProgess says that the rtc is updating, but we just fake it
 168      * by alternating it on every read of the bit since we are going to
 169      * override the loop_per_jiffy time that it is trying to use the UIP to
 170      * calculate.
 171      */
 172     uint8_t uip;
 173
 174     /** Mask of the PIC1 */
 175     uint8_t mask1;
 176
 177     /** Mask of the PIC2 */
 178     uint8_t mask2;
 179
 180     /** Mode of PIC1. Not used for anything */
 181     uint8_t mode1;
 182
 183     /** Mode of PIC2. Not used for anything */
 184     uint8_t mode2;
 185
 186     /** Raw PIC interrupt register before masking */
 187     uint8_t picr; //Raw PIC interrput register
 188
 189     /** Is the pic interrupting right now or not. */
 190     bool picInterrupting;
 191
 192     /** A pointer to the Tsunami device which be belong to */
 193     Tsunami *tsunami;
 194
 195     /**
 196      * This timer is initilized, but after I wrote the code
 197      * it doesn't seem to be used again, and best I can tell
 198      * it too is not connected to any interrupt port
 199      */
 200     ClockEvent timer0;
 201
 202     /**
 203      * This timer is used to control the speaker, which
 204      * we normally could care less about, however it is
 205      * also used to calculated the clockspeed and hense
 206      * bogomips which is kinda important to the scheduler
 207      * so we need to implemnt it although after boot I can't
 208      * imagine we would be playing with the PC speaker much
 209      */
 210     ClockEvent timer2;
 211
 212     /** This is the event used to interrupt the cpu like an RTC.  */
 213     RTCEvent rtc;
 214
 215     /** The interval is set via two writes to the PIT.
 216      * This variable contains a flag as to how many writes have happened, and
 217      * the time so far.
 218      */
 219     uint32_t timerData;
 220
 221
 222   public:
 223     /**
 224      * Return the freqency of the RTC
 225      * @return interrupt rate of the RTC
 226      */
 227     Tick  frequency() const { return RTC_RATE; }
 228
 229
 230     /**
 231      * Initialize all the data for devices supported by Tsunami I/O.
 232      * @param name name of this device.
 233      * @param t pointer back to the Tsunami object that we belong to.
 234      * @param init_time Time (as in seconds since 1970) to set RTC to.
 235      * @param a address we are mapped at.
 236      * @param mmu pointer to the memory controller that sends us events.
 237      */
 238     TsunamiIO(const std::string &name, Tsunami *t, time_t init_time,
 239               Addr a, MemoryController *mmu, HierParams *hier, Bus *bus);
 240
 241     /**
 242      * Create the tm struct from seconds since 1970
 243      */
 244     void set_time(time_t t);
 245
 246     /**
 247       * Process a read to one of the devices we are emulating.
 248       * @param req Contains the address to read from.
 249       * @param data A pointer to write the read data to.
 250       * @return The fault condition of the access.
 251       */
 252     virtual Fault read(MemReqPtr &req, uint8_t *data);
 253
 254     /**
 255       * Process a write to one of the devices we emulate.
 256       * @param req Contains the address to write to.
 257       * @param data The data to write.
 258       * @return The fault condition of the access.
 259       */
 260     virtual Fault write(MemReqPtr &req, const uint8_t *data);
 261
 262     /**
 263      * Post an PIC interrupt to the CPU via the CChip
 264      * @param bitvector interrupt to post.
 265      */
 266     void postPIC(uint8_t bitvector);
 267
 268     /**
 269      * Clear a posted interrupt
 270      * @param bitvector interrupt to clear
 271      */
 272     void clearPIC(uint8_t bitvector);
 273
 274     /**
 275      * Serialize this object to the given output stream.
 276      * @param os The stream to serialize to.
 277      */
 278     virtual void serialize(std::ostream &os);
 279
 280
 281     /**
 282      * Reconstruct the state of this object from a checkpoint.
 283      * @param cp The checkpoint use.
 284      * @param section The section name of this object
 285      */
 286     virtual void unserialize(Checkpoint *cp, const std::string &section);
 287
 288
 289     Tick cacheAccess(MemReqPtr &req);
 290 };
 291
 292 #endif // __TSUNAMI_IO_HH__