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authorAli Saidi <saidi@eecs.umich.edu>2006-03-21 15:45:31 -0500
committerAli Saidi <saidi@eecs.umich.edu>2006-03-21 15:45:31 -0500
commit8654cfa427d7346d7164946b91ea768e1fd64310 (patch)
tree0b6d8029165e8c4316970cddc83e8fc33c6b79f4 /dev/io_device.hh
parent5c6835ae3fb398fe8aa83ac8b4c806dd6e800b44 (diff)
downloadgem5-8654cfa427d7346d7164946b91ea768e1fd64310.tar.xz
Make PioPort/DmaPort,DmaDevice/PioDevice compile.
Add another type to the PacketResult enum of Unknown Seperate time into requsetTime and responseTime. dev/io_device.cc: dev/io_device.hh: Make PioPort/DmaPort,DmaDevice/PioDevice compile. mem/packet.hh: Add another type to the PacketResult enum of Unknown (e.g. no state set yet) mem/request.hh: Seperate time into requsetTime and responseTime. --HG-- extra : convert_revision : c6394cb838013296caea6492275252b8cae2882f
Diffstat (limited to 'dev/io_device.hh')
-rw-r--r--dev/io_device.hh125
1 files changed, 86 insertions, 39 deletions
diff --git a/dev/io_device.hh b/dev/io_device.hh
index a79c3f20a..8e44a1c00 100644
--- a/dev/io_device.hh
+++ b/dev/io_device.hh
@@ -32,30 +32,56 @@
#include "base/chunk_generator.hh"
#include "mem/port.hh"
#include "sim/eventq.hh"
+#include "sim/sim_object.hh"
-class Bus;
class Platform;
class PioDevice;
-
+class DmaDevice;
+
+/**
+ * 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. */
+ Platfrom *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)
- { return device->recvAtomic(pkt) };
+ virtual Tick recvAtomic(Packet &pkt);
- virtual void recvFunctional(Packet &pkt)
- { device->recvAtomic(pkt) };
+ virtual void recvFunctional(Packet &pkt) ;
- virtual void getDeviceAddressRanges(AddrRangeList &range_list, bool &owner)
- { device->addressRanges(range_list, owner); }
+ virtual void recvStatusChange(Status status)
+ { peerStatus = status; }
- void sendTiming(Packet &pkt, Tick time)
- { new SendEvent(this, pkt, time); }
+ virtual void getDeviceAddressRanges(AddrRangeList &range_list, bool &owner);
+ /**
+ * 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;
@@ -71,13 +97,19 @@ class PioPort : public Port
{ 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)
- : device(dev)
- { }
+ PioPort(PioDevice *dev, Platform *p);
+ friend class PioPort::SendEvent;
};
class DmaPort : public Port
@@ -85,10 +117,10 @@ class DmaPort : public Port
protected:
PioDevice *device;
std::list<Packet*> transmitList;
+ Event *completionEvent;
- virtual bool recvTiming(Packet &pkt)
- { completionEvent->schedule(curTick+1); completionEvent = NULL; }
+ 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)
@@ -97,23 +129,14 @@ class DmaPort : public Port
virtual void recvStatusChange(Status status)
{ ; }
- virtual Packet *recvRetry()
- { return transmitList.pop_front(); }
+ virtual Packet *recvRetry() ;
virtual void getDeviceAddressRanges(AddrRangeList &range_list, bool &owner)
{ range_list.clear(); owner = true; }
- void dmaAction(Memory::Command cmd, DmaPort port, Addr addr, int size,
- Event *event, uint8_t *data = NULL);
-
- void sendDma(Packet &pkt);
-
- virtual Packet *recvRetry()
- { return transmitList.pop_front(); }
-
class SendEvent : public Event
{
- PioPort *port;
+ DmaPort *port;
Packet packet;
SendEvent(PioPort *p, Packet &pkt, Tick t)
@@ -125,33 +148,55 @@ class DmaPort : public Port
virtual const char *description()
{ return "Future scheduled sendTiming event"; }
- friend class PioPort;
- }
+ friend class DmaPort;
+ };
+
+ void dmaAction(Command cmd, DmaPort port, Addr addr, int size,
+ Event *event, uint8_t *data = NULL);
+
+ void sendDma(Packet &pkt);
+
public:
- DmaPort(DmaDevice *dev)
- : device(dev)
- { }
+ DmaPort(DmaDevice *dev);
+ 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 SimObject
{
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, bool &owner) = 0;
- virtual read(Packet &pkt) = 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); }
- virtual write(Packet &pkt) = 0;
+ /** Pure virtual function that the device must implement. Called when a read
+ * command is recieved by the port. */
+ virtual bool read(Packet &pkt) = 0;
- 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
+ * write command is recieved by the port. */
+ virtual bool write(Packet &pkt) = 0;
public:
PioDevice(const std::string &name, Platform *p);
@@ -165,6 +210,8 @@ class PioDevice : public SimObject
else
return NULL;
}
+ friend class PioPort;
+
};
class DmaDevice : public PioDevice
@@ -180,14 +227,14 @@ class DmaDevice : public PioDevice
{
if (if_name == "pio")
return pioPort;
- else if (if_name = "dma")
+ else if (if_name == "dma")
return dmaPort;
else
return NULL;
}
-};
-
+ friend class DmaPort;
+};
#endif // __DEV_IO_DEVICE_HH__