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+/*
+ * Copyright (c) 2004-2005 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.
+ */
+
+#ifndef __DEV_IO_DEVICE_HH__
+#define __DEV_IO_DEVICE_HH__
+
+#include "base/chunk_generator.hh"
+#include "mem/mem_object.hh"
+#include "mem/packet_impl.hh"
+#include "sim/eventq.hh"
+#include "sim/sim_object.hh"
+
+class Platform;
+class PioDevice;
+class DmaDevice;
+class System;
+
+/**
+ * The PioPort class is a programmed i/o port that all devices that are
+ * sensitive to an address range use. The port takes all the memory
+ * access types and roles them into one read() and write() call that the device
+ * must respond to. The device must also provide the addressRanges() function
+ * with which it returns the address ranges it is interested in. An extra
+ * sendTiming() function is implemented which takes an delay. In this way the
+ * device can immediatly call sendTiming(pkt, time) after processing a request
+ * and the request will be handled by the port even if the port bus the device
+ * connects to is blocked.
+ */
+class PioPort : public Port
+{
+ protected:
+ /** The device that this port serves. */
+ PioDevice *device;
+
+ /** The platform that device/port are in. This is used to select which mode
+ * we are currently operating in. */
+ Platform *platform;
+
+ /** A list of outgoing timing response packets that haven't been serviced
+ * yet. */
+ std::list<Packet*> transmitList;
+
+ /** The current status of the peer(bus) that we are connected to. */
+ Status peerStatus;
+
+ virtual bool recvTiming(Packet *pkt);
+
+ virtual Tick recvAtomic(Packet *pkt);
+
+ virtual void recvFunctional(Packet *pkt) ;
+
+ virtual void recvStatusChange(Status status)
+ { peerStatus = status; }
+
+ virtual void getDeviceAddressRanges(AddrRangeList &resp, AddrRangeList &snoop);
+
+ /**
+ * This class is used to implemented sendTiming() with a delay. When a delay
+ * is requested a new event is created. When the event time expires it
+ * attempts to send the packet. If it cannot, the packet is pushed onto the
+ * transmit list to be sent when recvRetry() is called. */
+ class SendEvent : public Event
+ {
+ PioPort *port;
+ Packet *packet;
+
+ SendEvent(PioPort *p, Packet *pkt, Tick t)
+ : Event(&mainEventQueue), port(p), packet(pkt)
+ { schedule(curTick + t); }
+
+ virtual void process();
+
+ virtual const char *description()
+ { return "Future scheduled sendTiming event"; }
+
+ friend class PioPort;
+ };
+
+ /** Schedule a sendTiming() event to be called in the future. */
+ void sendTiming(Packet *pkt, Tick time)
+ { new PioPort::SendEvent(this, pkt, time); }
+
+ /** This function pops the last element off the transmit list and sends it.*/
+ virtual Packet *recvRetry();
+
+ public:
+ PioPort(PioDevice *dev, Platform *p);
+
+ friend class PioPort::SendEvent;
+};
+
+
+struct DmaReqState
+{
+ Event *completionEvent;
+ bool final;
+ DmaReqState(Event *ce, bool f)
+ : completionEvent(ce), final(f)
+ {}
+};
+
+class DmaPort : public Port
+{
+ protected:
+ DmaDevice *device;
+ std::list<Packet*> transmitList;
+
+ /** The platform that device/port are in. This is used to select which mode
+ * we are currently operating in. */
+ Platform *platform;
+
+ /** Number of outstanding packets the dma port has. */
+ int pendingCount;
+
+ virtual bool recvTiming(Packet *pkt);
+ virtual Tick recvAtomic(Packet *pkt)
+ { panic("dma port shouldn't be used for pio access."); }
+ virtual void recvFunctional(Packet *pkt)
+ { panic("dma port shouldn't be used for pio access."); }
+
+ virtual void recvStatusChange(Status status)
+ { ; }
+
+ virtual Packet *recvRetry() ;
+
+ virtual void getDeviceAddressRanges(AddrRangeList &resp, AddrRangeList &snoop)
+ { resp.clear(); snoop.clear(); }
+
+ class SendEvent : public Event
+ {
+ DmaPort *port;
+ Packet *packet;
+
+ SendEvent(PioPort *p, Packet *pkt, Tick t)
+ : Event(&mainEventQueue), packet(pkt)
+ { schedule(curTick + t); }
+
+ virtual void process();
+
+ virtual const char *description()
+ { return "Future scheduled sendTiming event"; }
+
+ friend class DmaPort;
+ };
+
+ void sendDma(Packet *pkt);
+
+ public:
+ DmaPort(DmaDevice *dev, Platform *p);
+
+ void dmaAction(Command cmd, Addr addr, int size, Event *event,
+ uint8_t *data = NULL);
+
+ bool dmaPending() { return pendingCount > 0; }
+
+ friend class DmaPort::SendEvent;
+
+};
+
+/**
+ * This device is the base class which all devices senstive to an address range
+ * inherit from. There are three pure virtual functions which all devices must
+ * implement addressRanges(), read(), and write(). The magic do choose which
+ * mode we are in, etc is handled by the PioPort so the device doesn't have to
+ * bother.
+ */
+
+class PioDevice : public MemObject
+{
+ protected:
+
+ /** The platform we are in. This is used to decide what type of memory
+ * transaction we should perform. */
+ Platform *platform;
+
+ /** The pioPort that handles the requests for us and provides us requests
+ * that it sees. */
+ PioPort *pioPort;
+
+ virtual void addressRanges(AddrRangeList &range_list) = 0;
+
+ /** As far as the devices are concerned they only accept atomic transactions
+ * which are converted to either a write or a read. */
+ Tick recvAtomic(Packet *pkt)
+ { return pkt->cmd == Read ? this->read(pkt) : this->write(pkt); }
+
+ /** Pure virtual function that the device must implement. Called when a read
+ * command is recieved by the port.
+ * @param pkt Packet describing this request
+ * @return number of ticks it took to complete
+ */
+ virtual Tick read(Packet *pkt) = 0;
+
+ /** Pure virtual function that the device must implement. Called when a
+ * write command is recieved by the port.
+ * @param pkt Packet describing this request
+ * @return number of ticks it took to complete
+ */
+ virtual Tick write(Packet *pkt) = 0;
+
+ public:
+ /** Params struct which is extended through each device based on the
+ * parameters it needs. Since we are re-writing everything, we might as well
+ * start from the bottom this time. */
+
+ struct Params
+ {
+ std::string name;
+ Platform *platform;
+ System *system;
+ };
+
+ protected:
+ Params *_params;
+
+ public:
+ const Params *params() const { return _params; }
+
+ PioDevice(Params *p)
+ : MemObject(p->name), platform(p->platform), pioPort(NULL),
+ _params(p)
+ {}
+
+ virtual ~PioDevice();
+
+ virtual void init();
+
+ virtual Port *getPort(const std::string &if_name)
+ {
+ if (if_name == "pio") {
+ if (pioPort != NULL)
+ panic("pio port already connected to.");
+ pioPort = new PioPort(this, params()->platform);
+ return pioPort;
+ } else
+ return NULL;
+ }
+ friend class PioPort;
+
+};
+
+class BasicPioDevice : public PioDevice
+{
+ public:
+ struct Params : public PioDevice::Params
+ {
+ Addr pio_addr;
+ Tick pio_delay;
+ };
+
+ protected:
+ /** Address that the device listens to. */
+ Addr pioAddr;
+
+ /** Size that the device's address range. */
+ Addr pioSize;
+
+ /** Delay that the device experinces on an access. */
+ Tick pioDelay;
+
+ public:
+ BasicPioDevice(Params *p)
+ : PioDevice(p), pioAddr(p->pio_addr), pioSize(0), pioDelay(p->pio_delay)
+ {}
+
+ /** return the address ranges that this device responds to.
+ * @params range_list range list to populate with ranges
+ */
+ void addressRanges(AddrRangeList &range_list);
+
+};
+
+class DmaDevice : public PioDevice
+{
+ protected:
+ DmaPort *dmaPort;
+
+ public:
+ DmaDevice(Params *p);
+ virtual ~DmaDevice();
+
+ void dmaWrite(Addr addr, int size, Event *event, uint8_t *data)
+ { dmaPort->dmaAction(Write, addr, size, event, data) ; }
+
+ void dmaRead(Addr addr, int size, Event *event, uint8_t *data = NULL)
+ { dmaPort->dmaAction(Read, addr, size, event, data); }
+
+ bool dmaPending() { return dmaPort->dmaPending(); }
+
+ virtual Port *getPort(const std::string &if_name)
+ {
+ if (if_name == "pio") {
+ if (pioPort != NULL)
+ panic("pio port already connected to.");
+ pioPort = new PioPort(this, params()->platform);
+ return pioPort;
+ } else if (if_name == "dma") {
+ if (dmaPort != NULL)
+ panic("dma port already connected to.");
+ dmaPort = new DmaPort(this, params()->platform);
+ return dmaPort;
+ } else
+ return NULL;
+ }
+
+ friend class DmaPort;
+};
+
+
+#endif // __DEV_IO_DEVICE_HH__
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