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Diffstat (limited to 'src/dev/io_device.hh')
-rw-r--r-- | src/dev/io_device.hh | 335 |
1 files changed, 335 insertions, 0 deletions
diff --git a/src/dev/io_device.hh b/src/dev/io_device.hh new file mode 100644 index 000000000..74730ad92 --- /dev/null +++ b/src/dev/io_device.hh @@ -0,0 +1,335 @@ +/* + * 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 : public Packet::SenderState +{ + 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(Packet::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->isRead() ? 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(Packet::WriteReq, addr, size, event, data) ; } + + void dmaRead(Addr addr, int size, Event *event, uint8_t *data = NULL) + { dmaPort->dmaAction(Packet::ReadReq, 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__ |