gem5/dev/tsunami_io.hh

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/*
* Copyright (c) 2004 The Regents of The University of Michigan
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met: redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer;
* redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution;
* neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/* @file
* Tsunami Fake I/O Space mapping including RTC/timer interrupts
*/
#ifndef __DEV_TSUNAMI_IO_HH__
#define __DEV_TSUNAMI_IO_HH__
#include "dev/io_device.hh"
#include "base/range.hh"
#include "dev/tsunami.hh"
#include "sim/eventq.hh"
/** How often the RTC interrupts */
static const int RTC_RATE = 1024;
/*
* Tsunami I/O device is a catch all for all the south bridge stuff we care
* to implement.
*/
class TsunamiIO : public PioDevice
{
private:
/** The base address of this device */
Addr addr;
/** The size of mappad from the above address */
static const Addr size = 0xff;
struct tm tm;
/**
* In Tsunami RTC only has two i/o ports one for data and one for
* address, so you write the address and then read/write the
* data. This store the address you are going to be reading from
* on a read.
*/
uint8_t RTCAddress;
protected:
/**
* The ClockEvent is handles the PIT interrupts
*/
class ClockEvent : public Event
{
protected:
/** how often the PIT fires */
Tick interval;
/** The mode of the PIT */
uint8_t mode;
/** The status of the PIT */
uint8_t status;
public:
/**
* Just set the mode to 0
*/
ClockEvent();
/**
* processs the timer event
*/
virtual void process();
/**
* Returns a description of this event
* @return the description
*/
virtual const char *description();
/**
* Schedule a timer interrupt to occur sometime in the future.
*/
void Program(int count);
/**
* Write the mode bits of the PIT.
* @param mode the new mode
*/
void ChangeMode(uint8_t mode);
/**
* The current PIT status.
* @return the status of the PIT
*/
uint8_t Status();
/**
* Serialize this object to the given output stream.
* @param os The stream to serialize to.
*/
virtual void serialize(std::ostream &os);
/**
* Reconstruct the state of this object from a checkpoint.
* @param cp The checkpoint use.
* @param section The section name of this object
*/
virtual void unserialize(Checkpoint *cp, const std::string &section);
};
/**
* Process RTC timer events and generate interrupts appropriately.
*/
class RTCEvent : public Event
{
protected:
/** A pointer back to tsunami to create interrupt the processor. */
Tsunami* tsunami;
public:
/** RTC Event initializes the RTC event by scheduling an event
* RTC_RATE times pre second. */
RTCEvent(Tsunami* t);
/**
* Interrupth the processor and reschedule the event.
*/
virtual void process();
/**
* Return a description of this event.
* @return a description
*/
virtual const char *description();
/**
* Serialize this object to the given output stream.
* @param os The stream to serialize to.
*/
virtual void serialize(std::ostream &os);
/**
* Reconstruct the state of this object from a checkpoint.
* @param cp The checkpoint use.
* @param section The section name of this object
*/
virtual void unserialize(Checkpoint *cp, const std::string &section);
};
/** uip UpdateInProgess says that the rtc is updating, but we just fake it
* by alternating it on every read of the bit since we are going to
* override the loop_per_jiffy time that it is trying to use the UIP to
* calculate.
*/
uint8_t uip;
/** Mask of the PIC1 */
uint8_t mask1;
/** Mask of the PIC2 */
uint8_t mask2;
/** Mode of PIC1. Not used for anything */
uint8_t mode1;
/** Mode of PIC2. Not used for anything */
uint8_t mode2;
/** Raw PIC interrupt register before masking */
uint8_t picr; //Raw PIC interrput register
/** Is the pic interrupting right now or not. */
bool picInterrupting;
/** A pointer to the Tsunami device which be belong to */
Tsunami *tsunami;
/**
* This timer is initilized, but after I wrote the code
* it doesn't seem to be used again, and best I can tell
* it too is not connected to any interrupt port
*/
ClockEvent timer0;
/**
* This timer is used to control the speaker, which
* we normally could care less about, however it is
* also used to calculated the clockspeed and hense
* bogomips which is kinda important to the scheduler
* so we need to implemnt it although after boot I can't
* imagine we would be playing with the PC speaker much
*/
ClockEvent timer2;
/** This is the event used to interrupt the cpu like an RTC. */
RTCEvent rtc;
/** The interval is set via two writes to the PIT.
* This variable contains a flag as to how many writes have happened, and
* the time so far.
*/
uint32_t timerData;
public:
/**
* Return the freqency of the RTC
* @return interrupt rate of the RTC
*/
Tick frequency() const { return RTC_RATE; }
/**
* Initialize all the data for devices supported by Tsunami I/O.
* @param name name of this device.
* @param t pointer back to the Tsunami object that we belong to.
* @param init_time Time (as in seconds since 1970) to set RTC to.
* @param a address we are mapped at.
* @param mmu pointer to the memory controller that sends us events.
*/
TsunamiIO(const std::string &name, Tsunami *t, time_t init_time,
Addr a, MemoryController *mmu, HierParams *hier, Bus *bus,
Tick pio_latency);
/**
* Create the tm struct from seconds since 1970
*/
void set_time(time_t t);
/**
* Process a read to one of the devices we are emulating.
* @param req Contains the address to read from.
* @param data A pointer to write the read data to.
* @return The fault condition of the access.
*/
virtual Fault read(MemReqPtr &req, uint8_t *data);
/**
* Process a write to one of the devices we emulate.
* @param req Contains the address to write to.
* @param data The data to write.
* @return The fault condition of the access.
*/
virtual Fault write(MemReqPtr &req, const uint8_t *data);
/**
* Post an PIC interrupt to the CPU via the CChip
* @param bitvector interrupt to post.
*/
void postPIC(uint8_t bitvector);
/**
* Clear a posted interrupt
* @param bitvector interrupt to clear
*/
void clearPIC(uint8_t bitvector);
/**
* Serialize this object to the given output stream.
* @param os The stream to serialize to.
*/
virtual void serialize(std::ostream &os);
/**
* Reconstruct the state of this object from a checkpoint.
* @param cp The checkpoint use.
* @param section The section name of this object
*/
virtual void unserialize(Checkpoint *cp, const std::string &section);
Tick cacheAccess(MemReqPtr &req);
};
#endif // __DEV_TSUNAMI_IO_HH__