DMA: Split the DMA device and IO device into seperate files

This patch moves the DMA device to its own set of files, splitting it
from the IO device. There are no behavioural changes associated with
this patch.

The patch also grabs the opportunity to do some very minor tidying up,
including some white space removal and pruning some redundant
parameters.

Besides the immediate benefits of the separation-of-concerns, this
patch also makes upcoming changes more streamlined as it split the
devices that are only slaves and the DMA device that also acts as a
master.

--HG--
rename : src/dev/io_device.cc => src/dev/dma_device.cc
rename : src/dev/io_device.hh => src/dev/dma_device.hh

1 files changed, 171 insertions, 0 deletions

diff --git a/src/dev/dma_device.hh b/src/dev/dma_device.hh
new file mode 100644
index 000000000..8fc4e664c
--- /dev/null
+++ b/src/dev/dma_device.hh
@@ -0,0 +1,171 @@
+/*
+ * Copyright (c) 2012 ARM Limited
+ * All rights reserved.
+ *
+ * The license below extends only to copyright in the software and shall
+ * not be construed as granting a license to any other intellectual
+ * property including but not limited to intellectual property relating
+ * to a hardware implementation of the functionality of the software
+ * licensed hereunder.  You may use the software subject to the license
+ * terms below provided that you ensure that this notice is replicated
+ * unmodified and in its entirety in all distributions of the software,
+ * modified or unmodified, in source code or in binary form.
+ *
+ * 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.
+ *
+ * Authors: Ali Saidi
+ *          Nathan Binkert
+ */
+
+#ifndef __DEV_DMA_DEVICE_HH__
+#define __DEV_DMA_DEVICE_HH__
+
+#include "dev/io_device.hh"
+#include "params/DmaDevice.hh"
+
+class DmaPort : public MasterPort
+{
+  protected:
+    struct DmaReqState : public Packet::SenderState, public FastAlloc
+    {
+        /** Event to call on the device when this transaction (all packets)
+         * complete. */
+        Event *completionEvent;
+
+        /** Total number of bytes that this transaction involves. */
+        Addr totBytes;
+
+        /** Number of bytes that have been acked for this transaction. */
+        Addr numBytes;
+
+        /** Amount to delay completion of dma by */
+        Tick delay;
+
+        DmaReqState(Event *ce, Addr tb, Tick _delay)
+            : completionEvent(ce), totBytes(tb), numBytes(0), delay(_delay)
+        {}
+    };
+
+    MemObject *device;
+    std::list<PacketPtr> transmitList;
+
+    /** The system that device/port are in. This is used to select which mode
+     * we are currently operating in. */
+    System *sys;
+
+    /** Id for all requests */
+    MasterID masterId;
+
+    /** Number of outstanding packets the dma port has. */
+    int pendingCount;
+
+    /** If a dmaAction is in progress. */
+    int actionInProgress;
+
+    /** If we need to drain, keep the drain event around until we're done
+     * here.*/
+    Event *drainEvent;
+
+    /** time to wait between sending another packet, increases as NACKs are
+     * recived, decreases as responses are recived. */
+    Tick backoffTime;
+
+    /** Minimum time that device should back off for after failed sendTiming */
+    Tick minBackoffDelay;
+
+    /** Maximum time that device should back off for after failed sendTiming */
+    Tick maxBackoffDelay;
+
+    /** If the port is currently waiting for a retry before it can send whatever
+     * it is that it's sending. */
+    bool inRetry;
+
+    virtual bool recvTimingResp(PacketPtr pkt);
+
+    virtual void recvRetry() ;
+
+    void queueDma(PacketPtr pkt, bool front = false);
+    void sendDma();
+
+    /** event to give us a kick every time we backoff time is reached. */
+    EventWrapper<DmaPort, &DmaPort::sendDma> backoffEvent;
+
+  public:
+    DmaPort(MemObject *dev, System *s, Tick min_backoff, Tick max_backoff);
+
+    void dmaAction(Packet::Command cmd, Addr addr, int size, Event *event,
+                   uint8_t *data, Tick delay, Request::Flags flag = 0);
+
+    bool dmaPending() { return pendingCount > 0; }
+
+    unsigned cacheBlockSize() const { return peerBlockSize(); }
+    unsigned int drain(Event *de);
+};
+
+class DmaDevice : public PioDevice
+{
+   protected:
+    DmaPort dmaPort;
+
+  public:
+    typedef DmaDeviceParams Params;
+    DmaDevice(const Params *p);
+    virtual ~DmaDevice();
+
+    const Params *
+    params() const
+    {
+        return dynamic_cast<const Params *>(_params);
+    }
+
+    void dmaWrite(Addr addr, int size, Event *event, uint8_t *data,
+                  Tick delay = 0)
+    {
+        dmaPort.dmaAction(MemCmd::WriteReq, addr, size, event, data, delay);
+    }
+
+    void dmaRead(Addr addr, int size, Event *event, uint8_t *data,
+                 Tick delay = 0)
+    {
+        dmaPort.dmaAction(MemCmd::ReadReq, addr, size, event, data, delay);
+    }
+
+    bool dmaPending() { return dmaPort.dmaPending(); }
+
+    virtual void init();
+
+    virtual unsigned int drain(Event *de);
+
+    unsigned cacheBlockSize() const { return dmaPort.cacheBlockSize(); }
+
+    virtual MasterPort &getMasterPort(const std::string &if_name,
+                                      int idx = -1);
+
+    friend class DmaPort;
+};
+
+#endif // __DEV_DMA_DEVICE_HH__