ARM: Add support for HDLCD controller for TC2 and newer Versatile Express tiles.

Newer core tiles / daughterboards for the Versatile Express platform have an
HDLCD controller that supports HD-quality output.  This patch adds an
implementation of the controller.

4 files changed, 1374 insertions, 0 deletions

diff --git a/src/dev/arm/RealView.py b/src/dev/arm/RealView.py
index f01572e40..b5d41ce93 100644
--- a/src/dev/arm/RealView.py
+++ b/src/dev/arm/RealView.py
@@ -142,6 +142,16 @@ class Pl111(AmbaDmaDevice):
     vnc   = Param.VncInput(Parent.any, "Vnc server for remote frame buffer display")
     amba_id = 0x00141111
 
+class HDLcd(AmbaDmaDevice):
+    type = 'HDLcd'
+    cxx_header = "dev/arm/hdlcd.hh"
+    pixel_clock = Param.Clock('65MHz', "Clock frequency of the pixel clock "
+                                       "(i.e. PXLREFCLK / OSCCLK 5; 23.75MHz "
+                                       "default up to 165MHz)")
+    vnc = Param.VncInput(Parent.any, "Vnc server for remote frame buffer "
+                                     "display")
+    amba_id = 0x00141000
+
 class RealView(Platform):
     type = 'RealView'
     cxx_header = "dev/arm/realview.hh"
@@ -333,6 +343,7 @@ class VExpress_EMM(RealView):
     timer0 = Sp804(int_num0=34, int_num1=34, pio_addr=0x1C110000, clock0='1MHz', clock1='1MHz')
     timer1 = Sp804(int_num0=35, int_num1=35, pio_addr=0x1C120000, clock0='1MHz', clock1='1MHz')
     clcd   = Pl111(pio_addr=0x1c1f0000, int_num=46)
+    hdlcd  = HDLcd(pio_addr=0x2b000000, int_num=117)
     kmi0   = Pl050(pio_addr=0x1c060000, int_num=44)
     kmi1   = Pl050(pio_addr=0x1c070000, int_num=45, is_mouse=True)
     cf_ctrl = IdeController(disks=[], pci_func=0, pci_dev=0, pci_bus=2,
@@ -376,9 +387,11 @@ class VExpress_EMM(RealView):
     def attachOnChipIO(self, bus, bridge):
        self.gic.pio = bus.master
        self.local_cpu_timer.pio = bus.master
+       self.hdlcd.dma           = bus.slave
        # Bridge ranges based on excluding what is part of on-chip I/O
        # (gic, a9scu)
        bridge.ranges = [AddrRange(0x2F000000, size='16MB'),
+                        AddrRange(0x2B000000, size='4MB'),
                         AddrRange(0x30000000, size='256MB'),
                         AddrRange(0x40000000, size='512MB'),
                         AddrRange(0x18000000, size='64MB'),
@@ -394,6 +407,7 @@ class VExpress_EMM(RealView):
        self.timer1.pio          = bus.master
        self.clcd.pio            = bus.master
        self.clcd.dma            = bus.slave
+       self.hdlcd.pio           = bus.master
        self.kmi0.pio            = bus.master
        self.kmi1.pio            = bus.master
        self.cf_ctrl.pio         = bus.master
diff --git a/src/dev/arm/SConscript b/src/dev/arm/SConscript
index 048fe2444..60a85220e 100644
--- a/src/dev/arm/SConscript
+++ b/src/dev/arm/SConscript
@@ -50,6 +50,7 @@ if env['TARGET_ISA'] == 'arm':
     Source('gic_pl390.cc')
     Source('pl011.cc')
     Source('pl111.cc')
+    Source('hdlcd.cc')
     Source('kmi.cc')
     Source('timer_sp804.cc')
     Source('rv_ctrl.cc')
@@ -58,6 +59,7 @@ if env['TARGET_ISA'] == 'arm':
     Source('timer_cpulocal.cc')
 
     DebugFlag('AMBA')
+    DebugFlag('HDLcd')
     DebugFlag('PL111')
     DebugFlag('Pl050')
     DebugFlag('GIC')
diff --git a/src/dev/arm/hdlcd.cc b/src/dev/arm/hdlcd.cc
new file mode 100644
index 000000000..14128c730
--- /dev/null
+++ b/src/dev/arm/hdlcd.cc
@@ -0,0 +1,856 @@
+/*
+ * Copyright (c) 2010-2013 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.
+ *
+ * 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: Chris Emmons
+ */
+
+#include "base/vnc/vncinput.hh"
+#include "base/bitmap.hh"
+#include "base/output.hh"
+#include "base/trace.hh"
+#include "debug/HDLcd.hh"
+#include "debug/Uart.hh"
+#include "dev/arm/amba_device.hh"
+#include "dev/arm/base_gic.hh"
+#include "dev/arm/hdlcd.hh"
+#include "mem/packet.hh"
+#include "mem/packet_access.hh"
+#include "sim/system.hh"
+
+using std::vector;
+
+
+// initialize hdlcd registers
+HDLcd::HDLcd(const Params *p)
+    : AmbaDmaDevice(p), version(VERSION_RESETV),
+      int_rawstat(0), int_clear(0), int_mask(0), int_status(0),
+      fb_base(0), fb_line_length(0), fb_line_count(0), fb_line_pitch(0),
+      bus_options(BUS_OPTIONS_RESETV),
+      v_sync(0), v_back_porch(0), v_data(0), v_front_porch(0),
+      h_sync(0), h_back_porch(0), h_data(0), h_front_porch(0),
+      polarities(0), command(0), pixel_format(0),
+      red_select(0), green_select(0), blue_select(0),
+      pixelClock(p->pixel_clock), vnc(p->vnc), bmp(NULL), pic(NULL),
+      frameReadStartTime(0),
+      dmaStartAddr(0), dmaCurAddr(0), dmaMaxAddr(0), dmaPendingNum(0),
+      frameUnderrun(false), virtualDisplayBuffer(NULL), pixelBufferSize(0),
+      pixelIndex(0), doUpdateParams(false), frameUnderway(false),
+      dmaBytesInFlight(0),
+      startFrameEvent(this), endFrameEvent(this), renderPixelEvent(this),
+      fillPixelBufferEvent(this), intEvent(this),
+      dmaDoneEventAll(MAX_OUTSTANDING_DMA_REQ_CAPACITY, this),
+      dmaDoneEventFree(MAX_OUTSTANDING_DMA_REQ_CAPACITY)
+{
+    pioSize = 0xFFFF;
+
+    for (int i = 0; i < MAX_OUTSTANDING_DMA_REQ_CAPACITY; ++i)
+        dmaDoneEventFree[i] = &dmaDoneEventAll[i];
+
+    if (vnc)
+        vnc->setFramebufferAddr(NULL);
+}
+
+HDLcd::~HDLcd()
+{
+    if (virtualDisplayBuffer)
+        delete [] virtualDisplayBuffer;
+}
+
+// read registers and frame buffer
+Tick
+HDLcd::read(PacketPtr pkt)
+{
+    uint32_t data = 0;
+    const Addr daddr = pkt->getAddr() - pioAddr;
+
+    DPRINTF(HDLcd, "read register BASE+0x%04x size=%d\n", daddr,
+            pkt->getSize());
+
+    assert(pkt->getAddr() >= pioAddr &&
+            pkt->getAddr() < pioAddr + pioSize &&
+            pkt->getSize() == 4);
+
+    pkt->allocate();
+
+    switch (daddr) {
+      case Version:
+        data = version;
+        break;
+      case Int_RawStat:
+        data = int_rawstat;
+        break;
+      case Int_Clear:
+        panic("HDLCD INT_CLEAR register is Write-Only\n");
+        break;
+      case Int_Mask:
+        data = int_mask;
+        break;
+      case Int_Status:
+        data = int_status;
+        break;
+      case Fb_Base:
+        data = fb_base;
+        break;
+      case Fb_Line_Length:
+        data = fb_line_length;
+        break;
+      case Fb_Line_Count:
+        data = fb_line_count;
+        break;
+      case Fb_Line_Pitch:
+        data = fb_line_pitch;
+        break;
+      case Bus_Options:
+        data = bus_options;
+        break;
+      case V_Sync:
+        data = v_sync;
+        break;
+      case V_Back_Porch:
+        data = v_back_porch;
+        break;
+      case V_Data:
+        data = v_data;
+        break;
+      case V_Front_Porch:
+        data = v_front_porch;
+        break;
+      case H_Sync:
+        data = h_sync;
+        break;
+      case H_Back_Porch:
+        data = h_back_porch;
+        break;
+      case H_Data:
+        data = h_data;
+        break;
+      case H_Front_Porch:
+        data = h_front_porch;
+        break;
+      case Polarities:
+        data = polarities;
+        break;
+      case Command:
+        data = command;
+        break;
+      case Pixel_Format:
+        data = pixel_format;
+        break;
+      case Red_Select:
+        data = red_select;
+        break;
+      case Green_Select:
+        data = green_select;
+        break;
+      case Blue_Select:
+        data = blue_select;
+        break;
+      default:
+        panic("Tried to read HDLCD register that doesn't  exist\n", daddr);
+        break;
+    }
+
+    pkt->set<uint32_t>(data);
+    pkt->makeAtomicResponse();
+    return pioDelay;
+}
+
+// write registers and frame buffer
+Tick
+HDLcd::write(PacketPtr pkt)
+{
+    assert(pkt->getAddr() >= pioAddr &&
+           pkt->getAddr() < pioAddr + pioSize &&
+           pkt->getSize() == 4);
+
+    const uint32_t data = pkt->get<uint32_t>();
+    const Addr daddr = pkt->getAddr() - pioAddr;
+
+    DPRINTF(HDLcd, "write register BASE+%0x04x <= 0x%08x\n", daddr,
+            pkt->get<uint32_t>());
+
+    switch (daddr) {
+      case Version:
+        panic("HDLCD VERSION register is read-Only\n");
+        break;
+      case Int_RawStat:
+        int_rawstat = data;
+        break;
+      case Int_Clear:
+        int_clear = data;
+        break;
+      case Int_Mask:
+        int_mask = data;
+        break;
+      case Int_Status:
+        panic("HDLCD INT_STATUS register is read-Only\n");
+        break;
+      case Fb_Base:
+        fb_base = data;
+        DPRINTF(HDLcd, "HDLCD Frame Buffer located at addr 0x%08x\n", fb_base);
+        break;
+      case Fb_Line_Length:
+        fb_line_length = data;
+        DPRINTF(HDLcd, "HDLCD res = %d x %d\n", width(), height());
+        break;
+      case Fb_Line_Count:
+        fb_line_count = data;
+        DPRINTF(HDLcd, "HDLCD res = %d x %d\n", width(), height());
+        break;
+      case Fb_Line_Pitch:
+        fb_line_pitch = data;
+        break;
+      case Bus_Options: {
+        BusOptsReg old_bus_options;
+        old_bus_options = bus_options;
+        bus_options = data;
+        if (bus_options.max_outstanding != old_bus_options.max_outstanding)
+            DPRINTF(HDLcd,
+                "Changing HDLcd outstanding dma transactions from %d to %d\n",
+                old_bus_options.max_outstanding, bus_options.max_outstanding);
+        if (bus_options.burst_len != old_bus_options.burst_len)
+            DPRINTF(HDLcd,
+                "Changing HDLcd dma burst length from %d bytes to %d bytes\n",
+                old_bus_options.burst_len, bus_options.burst_len); }
+        break;
+      case V_Sync:
+        v_sync = data;
+        break;
+      case V_Back_Porch:
+        v_back_porch = data;
+        break;
+      case V_Data:
+        v_data = data;
+        break;
+      case V_Front_Porch:
+        v_front_porch = data;
+        break;
+      case H_Sync:
+        h_sync = data;
+        break;
+      case H_Back_Porch:
+        h_back_porch = data;
+        break;
+      case H_Data:
+        h_data = data;
+        break;
+      case H_Front_Porch:
+        h_front_porch = data;
+        break;
+      case Polarities:
+        polarities = data;
+        break;
+      case Command: {
+        CommandReg new_command;
+        new_command = data;
+        if (new_command.enable != command.enable) {
+            DPRINTF(HDLcd, "HDLCD switched %s\n",
+                    new_command.enable==0 ? "off" : "on");
+            if (new_command.enable) {
+                doUpdateParams = true;
+                if (!frameUnderway) {
+                    schedule(startFrameEvent, nextCycle());
+                }
+            }
+        }
+        command = new_command; }
+        break;
+      case Pixel_Format:
+        pixel_format = data;
+        DPRINTF(HDLcd, "HDLCD res = %d x %d\n", width(), height());
+        DPRINTF(HDLcd, "HDLCD bytes per pixel = %d\n", bytesPerPixel());
+        DPRINTF(HDLcd, "HDLCD endianness = %s\n",
+                pixel_format.big_endian ? "big" : "little");
+        break;
+      case Red_Select:
+        red_select = data;
+        break;
+      case Green_Select:
+        green_select = data;
+        break;
+      case Blue_Select:
+        blue_select = data;
+        break;
+      default:
+        panic("Tried to write HDLCD register that doesn't exist\n", daddr);
+        break;
+    }
+
+    pkt->makeAtomicResponse();
+    return pioDelay;
+}
+
+void
+HDLcd::updateVideoParams(bool unserializing = false)
+{
+    const uint16_t bpp = bytesPerPixel() << 3;
+    const size_t buffer_size = bytesPerPixel() * width() * height();
+
+    // updating these parameters while LCD is enabled is not supported
+    if (frameUnderway && !unserializing)
+        panic("Attempting to change some HDLCD parameters while the controller"
+                " is active is not allowed");
+
+    // resize the virtualDisplayBuffer unless we are unserializing - it may
+    //   have changed size
+    // there must be no outstanding DMA transactions for this to work
+    if (!unserializing) {
+        assert(dmaPendingNum == 0);
+        if (virtualDisplayBuffer)
+            delete [] virtualDisplayBuffer;
+        virtualDisplayBuffer = new uint8_t[buffer_size];
+        memset(virtualDisplayBuffer, 0, buffer_size);
+    }
+
+    assert(virtualDisplayBuffer);
+    if (vnc)
+        vnc->setFramebufferAddr(virtualDisplayBuffer);
+
+    if (bmp)
+        delete bmp;
+
+    DPRINTF(HDLcd, "bpp = %d\n", bpp);
+    DPRINTF(HDLcd, "display size = %d x %d\n", width(), height());
+#if TRACING_ON
+    const size_t totalLinesPerFrame = v_back_porch.val + 1 +
+                                      v_data.val + 1 +
+                                      v_front_porch.val + 1 +
+                                      v_sync.val + 1;
+    const double fps = (double)SimClock::Frequency /
+            (double)(PClksPerLine() * totalLinesPerFrame * pixelClock);
+#endif
+    DPRINTF(HDLcd, "simulated refresh rate ~ %.1ffps generating ~ %.1fMB/s "
+            "traffic ([%.1fMHz, T=%d sim clocks] pclk, %d bpp => %.1fMB/s peak requirement)\n",
+            fps,
+            fps * buffer_size / 1024 / 1024,
+            (double)SimClock::Frequency / pixelClock / 1000000.0,
+            pixelClock,
+            bpp,
+            (double)(SimClock::Frequency / pixelClock * (bpp / 8)) / 1024 / 1024);
+
+    if (pixel_format.big_endian)
+        panic("Big Endian pixel format not implemented by HDLcd controller");
+
+    if (vnc) {
+        if ((bpp == 24) &&
+                (red_select.size == 8) &&
+                (blue_select.size == 8) &&
+                (green_select.size == 8) &&
+                (green_select.offset == 8)) {
+            if ((blue_select.offset == 0) &&
+                    (red_select.offset == 16)) {
+                vnc->setFrameBufferParams(VideoConvert::rgb8888, width(),
+                        height());
+                bmp = new Bitmap(VideoConvert::rgb8888, width(), height(),
+                        virtualDisplayBuffer);
+                DPRINTF(HDLcd, "color mode:  rgb888\n");
+            } else if ((red_select.offset == 0) &&
+                    (blue_select.offset == 16)) {
+                vnc->setFrameBufferParams(VideoConvert::bgr8888, width(),
+                        height());
+                bmp = new Bitmap(VideoConvert::bgr8888, width(), height(),
+                        virtualDisplayBuffer);
+                DPRINTF(HDLcd, "color mode:  bgr888\n");
+            }
+        } else if ((bpp == 16) &&
+                (red_select.size == 5) &&
+                (blue_select.size == 5) &&
+                (green_select.size == 6) &&
+                (green_select.offset == 5)) {
+            if ((blue_select.offset == 0) &&
+                    (red_select.offset == 11)) {
+                vnc->setFrameBufferParams(VideoConvert::rgb565, width(),
+                        height());
+                bmp = new Bitmap(VideoConvert::rgb565, width(), height(),
+                        virtualDisplayBuffer);
+                DPRINTF(HDLcd, "color mode:  rgb565\n");
+            } else if ((red_select.offset == 0) &&
+                    (blue_select.offset == 11)) {
+                vnc->setFrameBufferParams(VideoConvert::bgr565, width(),
+                        height());
+                bmp = new Bitmap(VideoConvert::bgr565, width(), height(),
+                        virtualDisplayBuffer);
+                DPRINTF(HDLcd, "color mode:  bgr565\n");
+            }
+        } else {
+            DPRINTF(HDLcd, "color mode:  undefined\n");
+            panic("Unimplemented video mode\n");
+        }
+    }
+}
+
+void
+HDLcd::startFrame()
+{
+    // 0. Check that we are in the appropriate state
+    assert(!frameUnderway);
+    if (!command.enable)
+        return;
+    DPRINTF(HDLcd, "Frame read started\n");
+    if (doUpdateParams) {
+        updateVideoParams();
+        doUpdateParams = false;
+    }
+    frameUnderway = true;
+    assert(virtualDisplayBuffer);
+    assert(pixelBufferSize == 0);
+    assert(dmaBytesInFlight == 0);
+    assert(dmaPendingNum == 0);
+    assert(dmaDoneEventFree.size() == dmaDoneEventAll.size());
+    assert(!renderPixelEvent.scheduled());
+    // currently only support positive line pitches equal to the line length
+    assert(width() * bytesPerPixel() == fb_line_pitch);
+
+    // 1. Start DMA'ing the frame; subsequent transactions created as we go
+    dmaCurAddr = dmaStartAddr = fb_base;
+    dmaMaxAddr = static_cast<Addr>(width() * height() * bytesPerPixel()) +
+                    dmaCurAddr;
+    frameReadStartTime = curTick();
+    pixelIndex = 0;
+    frameUnderrun = false;
+    fillPixelBuffer();
+
+    // 2. Schedule first pixelclock read; subsequent reads generated as we go
+    Tick firstPixelReadTick = curTick() + pixelClock * (
+                                  PClksPerLine() * (v_sync.val + 1 +
+                                                    v_back_porch.val + 1) +
+                                  h_sync.val + 1 +
+                                  h_back_porch.val + 1);
+    schedule(renderPixelEvent, firstPixelReadTick);
+}
+
+void
+HDLcd::fillPixelBuffer()
+{
+    // - am I under the LCD dma transaction total?
+    // - do I have more data to transfer?
+    // - have I not yet underrun for this frame?
+    // - is there room to put the data in the pixel buffer including any
+    //   outstanding dma transfers in flight?
+    while ((dmaPendingNum < maxOutstandingDma()) &&
+           (dmaMaxAddr > dmaCurAddr) &&
+           !frameUnderrun &&
+           bytesFreeInPixelBuffer() > dmaBurstLength() * AXI_PORT_WIDTH) {
+        // try largest transaction size allowed first but switch to smaller
+        // sizes for trailing bytes
+        size_t transaction_size = dmaBurstLength() * AXI_PORT_WIDTH;
+        while (transaction_size > (dmaMaxAddr - dmaCurAddr))
+            transaction_size >>= 1;
+        assert(transaction_size > 0);
+
+        // concurrent dma reads need different dma done events
+        // due to assertion in scheduling state
+        ++dmaPendingNum;
+
+        assert(!dmaDoneEventFree.empty());
+        DmaDoneEvent *event(dmaDoneEventFree.back());
+        dmaDoneEventFree.pop_back();
+        assert(event);
+        assert(!event->scheduled());
+
+        // We use a uncachable request here because the requests from the CPU
+        // will be uncacheable as well. If we have uncacheable and cacheable
+        // requests in the memory system for the same address it won't be
+        // pleased
+        event->setTransactionSize(transaction_size);
+        dmaPort.dmaAction(MemCmd::ReadReq, dmaCurAddr, transaction_size, event,
+                          virtualDisplayBuffer + dmaCurAddr - dmaStartAddr,
+                          0, Request::UNCACHEABLE);
+        dmaCurAddr += transaction_size;
+        dmaBytesInFlight += transaction_size;
+    }
+}
+
+void
+HDLcd::renderPixel()
+{
+    // try to handle multiple pixels at a time; doing so reduces the accuracy
+    //   of the underrun detection but lowers simulation overhead
+    const size_t count = 32;
+    assert(width() % count == 0); // not set up to handle trailing pixels
+
+    // have we underrun on this frame anytime before?
+    if (frameUnderrun) {
+        // the LCD controller gives up on a frame if an underrun occurs and
+        //   resumes regular operation on the next frame
+        pixelBufferSize = 0;
+    } else {
+        // did we underrun on this set of pixels?
+        if (pixelBufferSize < bytesPerPixel() * count) {
+            warn("HDLcd controller buffer underrun\n");
+            frameUnderrun = true;
+            int_rawstat.underrun = 1;
+            if (!intEvent.scheduled())
+                schedule(intEvent, nextCycle());
+        } else {
+            // emulate the pixel read from the internal buffer
+            pixelBufferSize -= bytesPerPixel() * count;
+        }
+    }
+
+    // the DMA may have previously stalled due to the buffer being full;
+    //   give it a kick; it knows not to fill if at end of frame, underrun, etc
+    if (!fillPixelBufferEvent.scheduled())
+        schedule(fillPixelBufferEvent, nextCycle());
+
+    // schedule the next pixel read according to where it is in the frame
+    pixelIndex += count;
+    assert(pixelIndex <= width() * height());
+    size_t x = pixelIndex % width();
+    Tick nextEventTick = curTick();
+    if (x == 0) {
+        // start of new line
+        nextEventTick += pixelClock * ((h_front_porch.val + 1) +
+                                       (h_back_porch.val + 1) +
+                                       (h_sync.val + 1));
+        if (pixelIndex == width() * height()) {
+            // end of frame
+            nextEventTick += PClksPerLine() * (v_front_porch.val + 1) *
+                             pixelClock;
+            schedule(endFrameEvent, nextEventTick);
+            return;
+        }
+    } else {
+        nextEventTick += pixelClock * count;
+    }
+
+    schedule(renderPixelEvent, nextEventTick);
+}
+
+void
+HDLcd::endFrame() {
+    assert(pixelBufferSize == 0);
+    assert(dmaPendingNum == 0);
+    assert(dmaBytesInFlight == 0);
+    assert(dmaDoneEventFree.size() == dmaDoneEventAll.size());
+
+    if (vnc)
+        vnc->setDirty();
+
+    if (!pic)
+        pic = simout.create(csprintf("%s.framebuffer.bmp", sys->name()), true);
+
+    assert(bmp);
+    assert(pic);
+    pic->seekp(0);
+    bmp->write(pic);
+
+    // start the next frame
+    frameUnderway = false;
+    startFrame();
+}
+
+void
+HDLcd::dmaDone(DmaDoneEvent *event)
+{
+    const size_t transactionLength = event->getTransactionSize();
+    assert(pixelBufferSize + transactionLength < PIXEL_BUFFER_CAPACITY);
+    assert(dmaCurAddr <= dmaMaxAddr);
+
+    dmaDoneEventFree.push_back(event);
+    --dmaPendingNum;
+    assert(MAX_OUTSTANDING_DMA_REQ_CAPACITY - dmaDoneEventFree.size() ==
+            dmaPendingNum);
+
+    // add the data to the pixel buffer
+    dmaBytesInFlight -= transactionLength;
+    pixelBufferSize += transactionLength;
+
+    // schedule another dma transaction if:
+    // - we're not done reading the frame
+    // - there is sufficient room in the pixel buffer for another transaction
+    // - another fillPixelBufferEvent is not already scheduled
+    const size_t targetTransSize = dmaBurstLength() * AXI_PORT_WIDTH;
+    if ((dmaCurAddr < dmaMaxAddr) &&
+        (bytesFreeInPixelBuffer() + targetTransSize < PIXEL_BUFFER_CAPACITY) &&
+        !fillPixelBufferEvent.scheduled()) {
+        schedule(fillPixelBufferEvent, nextCycle());
+    }
+}
+
+void
+HDLcd::serialize(std::ostream &os)
+{
+    DPRINTF(HDLcd, "Serializing ARM HDLCD\n");
+
+    const uint32_t version_serial = version;
+    SERIALIZE_SCALAR(version_serial);
+    const uint32_t int_rawstat_serial = int_rawstat;
+    SERIALIZE_SCALAR(int_rawstat_serial);
+    const uint32_t int_clear_serial = int_clear;
+    SERIALIZE_SCALAR(int_clear_serial);
+    const uint32_t int_mask_serial = int_mask;
+    SERIALIZE_SCALAR(int_mask_serial);
+    const uint32_t int_status_serial = int_status;
+    SERIALIZE_SCALAR(int_status_serial);
+
+    SERIALIZE_SCALAR(fb_base);
+    SERIALIZE_SCALAR(fb_line_length);
+
+    const uint32_t fb_line_count_serial = fb_line_count;
+    SERIALIZE_SCALAR(fb_line_count_serial);
+
+    SERIALIZE_SCALAR(fb_line_pitch);
+
+    const uint32_t bus_options_serial = bus_options;
+    SERIALIZE_SCALAR(bus_options_serial);
+    const uint32_t v_sync_serial = v_sync;
+    SERIALIZE_SCALAR(v_sync_serial);
+    const uint32_t v_back_porch_serial = v_back_porch;
+    SERIALIZE_SCALAR(v_back_porch_serial);
+    const uint32_t v_data_serial = v_data;
+    SERIALIZE_SCALAR(v_data_serial);
+    const uint32_t v_front_porch_serial = v_front_porch;
+    SERIALIZE_SCALAR(v_front_porch_serial);
+    const uint32_t h_sync_serial = h_sync;
+    SERIALIZE_SCALAR(h_sync_serial);
+    const uint32_t h_back_porch_serial = h_back_porch;
+    SERIALIZE_SCALAR(h_back_porch_serial);
+    const uint32_t h_data_serial = h_data;
+    SERIALIZE_SCALAR(h_data_serial);
+    const uint32_t h_front_porch_serial = h_front_porch;
+    SERIALIZE_SCALAR(h_front_porch_serial);
+    const uint32_t polarities_serial = polarities;
+    SERIALIZE_SCALAR(polarities_serial);
+    const uint32_t command_serial = command;
+    SERIALIZE_SCALAR(command_serial);
+    const uint32_t pixel_format_serial = pixel_format;
+    SERIALIZE_SCALAR(pixel_format_serial);
+    const uint32_t red_select_serial = red_select;
+    SERIALIZE_SCALAR(red_select_serial);
+    const uint32_t green_select_serial = green_select;
+    SERIALIZE_SCALAR(green_select_serial);
+    const uint32_t blue_select_serial = blue_select;
+    SERIALIZE_SCALAR(blue_select_serial);
+
+    SERIALIZE_SCALAR(frameReadStartTime);
+    SERIALIZE_SCALAR(dmaStartAddr);
+    SERIALIZE_SCALAR(dmaCurAddr);
+    SERIALIZE_SCALAR(dmaMaxAddr);
+    SERIALIZE_SCALAR(dmaPendingNum);
+    SERIALIZE_SCALAR(frameUnderrun);
+
+    const size_t buffer_size = bytesPerPixel() * width() * height();
+    SERIALIZE_ARRAY(virtualDisplayBuffer, buffer_size);
+
+    SERIALIZE_SCALAR(pixelBufferSize);
+    SERIALIZE_SCALAR(pixelIndex);
+    SERIALIZE_SCALAR(doUpdateParams);
+    SERIALIZE_SCALAR(frameUnderway);
+    SERIALIZE_SCALAR(dmaBytesInFlight);
+
+    Tick start_event_time = 0;
+    Tick end_event_time = 0;
+    Tick render_pixel_event_time = 0;
+    Tick fill_pixel_buffer_event_time = 0;
+    Tick int_event_time = 0;
+    if (startFrameEvent.scheduled())
+        start_event_time = startFrameEvent.when();
+    if (endFrameEvent.scheduled())
+        end_event_time = endFrameEvent.when();
+    if (renderPixelEvent.scheduled())
+        render_pixel_event_time = renderPixelEvent.when();
+    if (fillPixelBufferEvent.scheduled())
+        fill_pixel_buffer_event_time = fillPixelBufferEvent.when();
+    if (intEvent.scheduled())
+        int_event_time = intEvent.when();
+    SERIALIZE_SCALAR(start_event_time);
+    SERIALIZE_SCALAR(end_event_time);
+    SERIALIZE_SCALAR(render_pixel_event_time);
+    SERIALIZE_SCALAR(fill_pixel_buffer_event_time);
+    SERIALIZE_SCALAR(int_event_time);
+
+    vector<Tick> dma_done_event_tick(MAX_OUTSTANDING_DMA_REQ_CAPACITY);
+    vector<size_t> dma_done_event_burst_len(MAX_OUTSTANDING_DMA_REQ_CAPACITY);
+    for (int x = 0; x < MAX_OUTSTANDING_DMA_REQ_CAPACITY; ++x) {
+        dma_done_event_tick[x] = dmaDoneEventAll[x].scheduled() ?
+            dmaDoneEventAll[x].when() : 0;
+        dma_done_event_burst_len[x] = dmaDoneEventAll[x].scheduled() ?
+            dmaDoneEventAll[x].getTransactionSize() : 0;
+    }
+    arrayParamOut(os, "dma_done_event_tick", dma_done_event_tick);
+    arrayParamOut(os, "dma_done_event_burst_length", dma_done_event_burst_len);
+}
+
+void
+HDLcd::unserialize(Checkpoint *cp, const std::string &section)
+{
+    uint32_t version_serial, int_rawstat_serial, int_clear_serial,
+            int_mask_serial, int_status_serial, fb_line_count_serial,
+            bus_options_serial, v_sync_serial, v_back_porch_serial,
+            v_data_serial, v_front_porch_serial, h_sync_serial,
+            h_back_porch_serial, h_data_serial, h_front_porch_serial,
+            polarities_serial, command_serial, pixel_format_serial,
+            red_select_serial, green_select_serial, blue_select_serial;
+
+    DPRINTF(HDLcd, "Unserializing ARM HDLCD\n");
+
+    UNSERIALIZE_SCALAR(version_serial);
+    version = version_serial;
+    UNSERIALIZE_SCALAR(int_rawstat_serial);
+    int_rawstat = int_rawstat_serial;
+    UNSERIALIZE_SCALAR(int_clear_serial);
+    int_clear = int_clear_serial;
+    UNSERIALIZE_SCALAR(int_mask_serial);
+    int_mask = int_mask_serial;
+    UNSERIALIZE_SCALAR(int_status_serial);
+    int_status = int_status_serial;
+
+    UNSERIALIZE_SCALAR(fb_base);
+    UNSERIALIZE_SCALAR(fb_line_length);
+
+    UNSERIALIZE_SCALAR(fb_line_count_serial);
+    fb_line_count = fb_line_count_serial;
+
+    UNSERIALIZE_SCALAR(fb_line_pitch);
+
+    UNSERIALIZE_SCALAR(bus_options_serial);
+    bus_options = bus_options_serial;
+    UNSERIALIZE_SCALAR(v_sync_serial);
+    v_sync = v_sync_serial;
+    UNSERIALIZE_SCALAR(v_back_porch_serial);
+    v_back_porch = v_back_porch_serial;
+    UNSERIALIZE_SCALAR(v_data_serial);
+    v_data = v_data_serial;
+    UNSERIALIZE_SCALAR(v_front_porch_serial);
+    v_front_porch = v_front_porch_serial;
+    UNSERIALIZE_SCALAR(h_sync_serial);
+    h_sync = h_sync_serial;
+    UNSERIALIZE_SCALAR(h_back_porch_serial);
+    h_back_porch = h_back_porch_serial;
+    UNSERIALIZE_SCALAR(h_data_serial);
+    h_data = h_data_serial;
+    UNSERIALIZE_SCALAR(h_front_porch_serial);
+    h_front_porch = h_front_porch_serial;
+    UNSERIALIZE_SCALAR(polarities_serial);
+    polarities = polarities_serial;
+    UNSERIALIZE_SCALAR(command_serial);
+    command = command_serial;
+    UNSERIALIZE_SCALAR(pixel_format_serial);
+    pixel_format = pixel_format_serial;
+    UNSERIALIZE_SCALAR(red_select_serial);
+    red_select = red_select_serial;
+    UNSERIALIZE_SCALAR(green_select_serial);
+    green_select = green_select_serial;
+    UNSERIALIZE_SCALAR(blue_select_serial);
+    blue_select = blue_select_serial;
+
+    UNSERIALIZE_SCALAR(frameReadStartTime);
+    UNSERIALIZE_SCALAR(dmaStartAddr);
+    UNSERIALIZE_SCALAR(dmaCurAddr);
+    UNSERIALIZE_SCALAR(dmaMaxAddr);
+    UNSERIALIZE_SCALAR(dmaPendingNum);
+    UNSERIALIZE_SCALAR(frameUnderrun);
+    UNSERIALIZE_SCALAR(dmaBytesInFlight);
+
+    const size_t buffer_size = bytesPerPixel() * width() * height();
+    virtualDisplayBuffer = new uint8_t[buffer_size];
+    UNSERIALIZE_ARRAY(virtualDisplayBuffer, buffer_size);
+
+    UNSERIALIZE_SCALAR(pixelBufferSize);
+    UNSERIALIZE_SCALAR(pixelIndex);
+    UNSERIALIZE_SCALAR(doUpdateParams);
+    UNSERIALIZE_SCALAR(frameUnderway);
+
+    Tick start_event_time = 0;
+    Tick end_event_time = 0;
+    Tick render_pixel_event_time = 0;
+    Tick fill_pixel_buffer_event_time = 0;
+    Tick int_event_time = 0;
+    UNSERIALIZE_SCALAR(start_event_time);
+    UNSERIALIZE_SCALAR(end_event_time);
+    UNSERIALIZE_SCALAR(render_pixel_event_time);
+    UNSERIALIZE_SCALAR(fill_pixel_buffer_event_time);
+    UNSERIALIZE_SCALAR(int_event_time);
+    if (start_event_time)
+        schedule(startFrameEvent, start_event_time);
+    if (end_event_time)
+        schedule(endFrameEvent, end_event_time);
+    if (render_pixel_event_time)
+        schedule(renderPixelEvent, render_pixel_event_time);
+    if (fill_pixel_buffer_event_time)
+        schedule(fillPixelBufferEvent, fill_pixel_buffer_event_time);
+    if (int_event_time)
+        schedule(intEvent, int_event_time);
+
+    vector<Tick> dma_done_event_tick(MAX_OUTSTANDING_DMA_REQ_CAPACITY);
+    vector<Tick> dma_done_event_burst_len(MAX_OUTSTANDING_DMA_REQ_CAPACITY);
+    arrayParamIn(cp, section, "dma_done_event_tick", dma_done_event_tick);
+    arrayParamIn(cp, section, "dma_done_event_burst_length", dma_done_event_burst_len);
+    dmaDoneEventFree.clear();
+    for (int x = 0; x < MAX_OUTSTANDING_DMA_REQ_CAPACITY; ++x) {
+        if (dma_done_event_tick[x]) {
+            dmaDoneEventAll[x].setTransactionSize(dma_done_event_burst_len[x]);
+            schedule(dmaDoneEventAll[x], dma_done_event_tick[x]);
+        } else
+            dmaDoneEventFree.push_back(&dmaDoneEventAll[x]);
+    }
+    assert(MAX_OUTSTANDING_DMA_REQ_CAPACITY - dmaDoneEventFree.size() == dmaPendingNum);
+
+    if (frameUnderway) {
+        updateVideoParams(true);
+        if (vnc)
+            vnc->setDirty();
+    }
+}
+
+void
+HDLcd::generateInterrupt()
+{
+    int_status = int_rawstat & int_mask;
+    DPRINTF(HDLcd, "Generate Interrupt: int_rawstat=0x%08x int_mask=0x%08x "
+            "int_status=0x%08x\n",
+            (uint32_t)int_rawstat, (uint32_t)int_mask, (uint32_t)int_status);
+
+    if (int_status != 0) {
+        gic->sendInt(intNum);
+        DPRINTF(HDLcd, " -- Generated\n");
+    }
+}
+
+AddrRangeList
+HDLcd::getAddrRanges() const
+{
+    AddrRangeList ranges;
+    ranges.push_back(RangeSize(pioAddr, pioSize));
+    return ranges;
+}
+
+HDLcd *
+HDLcdParams::create()
+{
+    return new HDLcd(this);
+}
diff --git a/src/dev/arm/hdlcd.hh b/src/dev/arm/hdlcd.hh
new file mode 100644
index 000000000..ab4df5ed6
--- /dev/null
+++ b/src/dev/arm/hdlcd.hh
@@ -0,0 +1,502 @@
+/*
+ * Copyright (c) 2010-2013 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.
+ *
+ * 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: Chris Emmons
+ */
+
+
+/** @file
+ * Implementiation of the ARM HDLcd controller.
+ *
+ * This implementation aims to have sufficient detail such that underrun
+ * conditions are reasonable / behave similar to reality.  There are two
+ * 'engines' going at once.  First, the DMA engine running at LCD clock
+ * frequency is responsible for filling the controller's internal buffer.
+ * The second engine runs at the pixel clock frequency and reads the pixels
+ * out of the internal buffer.  The pixel rendering engine uses front / back
+ * porch and sync delays between lines and frames.
+ *
+ * If the pixel rendering engine does not have a pixel to display, it will
+ * cause an underrun event.  The HDLcd controller, per spec, will stop
+ * issuing DMA requests for the rest of the frame and resume normal behavior
+ * on the subsequent frame.  What pixels are rendered upon an underrun
+ * condition is different than the real hardware; while the user will see
+ * artifacts (previous frame mixed with current frame), it is not the same
+ * behavior as real hardware which repeats the last pixel value for the rest
+ * of the current frame.  This compromise was made to save on memory and
+ * complexity and assumes that it is not important to accurately model the
+ * content of an underrun frame.
+ *
+ * KNOWN ISSUES
+ * 1.  The default kernel driver used in testing sets the line count to one
+ * less than the expected 768.  However, it also sets the v_count to 767.
+ * The controller specifies that 1 should be added to v_count but does not
+ * specify adding 1 to the line count.  The driver is probably wrong.
+ * However, to sync these two numbers up, this model uses fb_line_count and
+ * fb_line_length rather than using v_data or h_data values to determine the
+ * width and height of the frame; those values are ignored.
+ * 2.  The HDLcd is implemented here as an AmbaDmaDevice, but it doesn't have
+ * an AMBA ID as far as I know.  That is the only bit of the AmbaDmaDevice
+ * interface that is irrelevant to it, so a fake AMBA ID is used for now.
+ * I didn't think inserting an extra layer of hierachy between AmbaDmaDevice
+ * and DmaDevice would be helpful to anyone else, but that may be the right
+ * answer.
+ * 3.  The internal buffer size is either 1 or 2 KB depending on which
+ * specification is referenced for the different Versatile Express tiles.
+ * This implementation uses the larger 2 KB buffer by default.
+ */
+
+#ifndef __DEV_ARM_HDLCD_HH__
+#define __DEV_ARM_HDLCD_HH__
+
+#include <fstream>
+
+#include "dev/arm/amba_device.hh"
+#include "params/HDLcd.hh"
+#include "sim/serialize.hh"
+
+class VncInput;
+class Bitmap;
+
+class HDLcd: public AmbaDmaDevice
+{
+  protected:
+    /** fake AMBA ID -- unused */
+    static const uint64_t AMBA_ID       = ULL(0xb105f00d00141000);
+
+    /** ARM HDLcd register offsets */
+    enum RegisterOffset {
+        Version          = 0x0000,
+        Int_RawStat      = 0x0010,
+        Int_Clear        = 0x0014,
+        Int_Mask         = 0x0018,
+        Int_Status       = 0x001C,
+        Fb_Base          = 0x0100,
+        Fb_Line_Length   = 0x0104,
+        Fb_Line_Count    = 0x0108,
+        Fb_Line_Pitch    = 0x010C,
+        Bus_Options      = 0x0110,
+        V_Sync           = 0x0200,
+        V_Back_Porch     = 0x0204,
+        V_Data           = 0x0208,
+        V_Front_Porch    = 0x020C,
+        H_Sync           = 0x0210,
+        H_Back_Porch     = 0x0214,
+        H_Data           = 0x0218,
+        H_Front_Porch    = 0x021C,
+        Polarities       = 0x0220,
+        Command          = 0x0230,
+        Pixel_Format     = 0x0240,
+        Red_Select       = 0x0244,
+        Green_Select     = 0x0248,
+        Blue_Select      = 0x024C };
+
+    /** Reset value for Bus_Options register */
+    static const size_t BUS_OPTIONS_RESETV = 0x408;
+
+    /** Reset value for Version register */
+    static const size_t VERSION_RESETV = 0x1CDC0000;
+
+    /** max number of outstanding DMA requests possible */
+    static const size_t MAX_OUTSTANDING_DMA_REQ_CAPACITY = 16;
+
+    /** max number of beats delivered in one dma burst */
+    static const size_t MAX_BURST_LEN = 16;
+
+    /** size of internal buffer in bytes */
+    static const size_t PIXEL_BUFFER_CAPACITY = 2048;
+
+    /** AXI port width in bytes */
+    static const size_t AXI_PORT_WIDTH = 8;
+
+    /**
+     * @name RegisterFieldLayouts
+     * Bit layout declarations for multi-field registers.
+     */
+    /**@{*/
+    BitUnion32(VersionReg)
+        Bitfield<7,0>   version_minor;
+        Bitfield<15,8>  version_major;
+        Bitfield<31,16> product_id;
+    EndBitUnion(VersionReg)
+
+    BitUnion32(InterruptReg)
+        Bitfield<0> dma_end;
+        Bitfield<1> bus_error;
+        Bitfield<2> vsync;
+        Bitfield<3> underrun;
+    EndBitUnion(InterruptReg)
+
+    BitUnion32(FbLineCountReg)
+        Bitfield<11,0>  fb_line_count;
+        Bitfield<31,12> reserved_31_12;
+    EndBitUnion(FbLineCountReg)
+
+    BitUnion32(BusOptsReg)
+        Bitfield<4,0>   burst_len;
+        Bitfield<7,5>   reserved_7_5;
+        Bitfield<11,8>  max_outstanding;
+        Bitfield<31,12> reserved_31_12;
+    EndBitUnion(BusOptsReg)
+
+    BitUnion32(TimingReg)
+        Bitfield<11,0>  val;
+        Bitfield<31,12> reserved_31_12;
+    EndBitUnion(TimingReg)
+
+    BitUnion32(PolaritiesReg)
+        Bitfield<0>    vsync_polarity;
+        Bitfield<1>    hsync_polarity;
+        Bitfield<2>    dataen_polarity;
+        Bitfield<3>    data_polarity;
+        Bitfield<4>    pxlclk_polarity;
+        Bitfield<31,5> reserved_31_5;
+    EndBitUnion(PolaritiesReg)
+
+    BitUnion32(CommandReg)
+        Bitfield<0>    enable;
+        Bitfield<31,1> reserved_31_1;
+    EndBitUnion(CommandReg)
+
+    BitUnion32(PixelFormatReg)
+        Bitfield<2,0>  reserved_2_0;
+        Bitfield<4,3>  bytes_per_pixel;
+        Bitfield<30,5> reserved_30_5;
+        Bitfield<31>   big_endian;
+    EndBitUnion(PixelFormatReg)
+
+    BitUnion32(ColorSelectReg)
+        Bitfield<4,0>   offset;
+        Bitfield<7,5>   reserved_7_5;
+        Bitfield<11,8>  size;
+        Bitfield<15,12> reserved_15_12;
+        Bitfield<23,16> default_color;
+        Bitfield<31,24> reserved_31_24;
+    EndBitUnion(ColorSelectReg)
+    /**@}*/
+
+    /**
+     * @name HDLCDRegisters
+     * HDLCD register contents.
+     */
+    /**@{*/
+    VersionReg version;             /**< Version register */
+    InterruptReg int_rawstat;       /**< Interrupt raw status register */
+    InterruptReg int_clear;         /**< Interrupt clear register */
+    InterruptReg int_mask;          /**< Interrupt mask register */
+    InterruptReg int_status;        /**< Interrupt status register */
+    uint32_t fb_base;               /**< Frame buffer base address register */
+    uint32_t fb_line_length;        /**< Frame buffer Line length register */
+    FbLineCountReg fb_line_count;   /**< Frame buffer Line count register */
+    uint32_t fb_line_pitch;         /**< Frame buffer Line pitch register */
+    BusOptsReg bus_options;         /**< Bus options register */
+    TimingReg v_sync;               /**< Vertical sync width register */
+    TimingReg v_back_porch;         /**< Vertical back porch width register */
+    TimingReg v_data;               /**< Vertical data width register */
+    TimingReg v_front_porch;        /**< Vertical front porch width register */
+    TimingReg h_sync;               /**< Horizontal sync width register */
+    TimingReg h_back_porch;         /**< Horizontal back porch width register */
+    TimingReg h_data;               /**< Horizontal data width register */
+    TimingReg h_front_porch;        /**< Horizontal front porch width reg */
+    PolaritiesReg polarities;       /**< Polarities register */
+    CommandReg command;             /**< Command register */
+    PixelFormatReg pixel_format;    /**< Pixel format register */
+    ColorSelectReg red_select;      /**< Red color select register */
+    ColorSelectReg green_select;    /**< Green color select register */
+    ColorSelectReg blue_select;     /**< Blue color select register */
+    /** @} */
+
+    /** Pixel clock period */
+    const Tick pixelClock;
+
+    /** VNC server */
+    VncInput *vnc;
+
+    /** Helper to write out bitmaps */
+    Bitmap *bmp;
+
+    /** Picture of what the current frame buffer looks like */
+    std::ostream *pic;
+
+    /**
+     * Event wrapper for dmaDone()
+     *
+     * This event call pushes its this pointer onto the freeDoneEvent vector
+     * and calls dmaDone() when triggered.  While most of the time the burst
+     * length of a transaction will be the max burst length set by the driver,
+     * any trailing bytes must be handled with smaller lengths thus requiring
+     * the configurable burst length option.
+     */
+    class DmaDoneEvent : public Event
+    {
+      private:
+        /** Reference to HDLCD that issued the corresponding DMA transaction */
+        HDLcd &obj;
+
+        /** Transaction size */
+        size_t transSize;
+
+      public:
+        /**
+         * Constructor.
+         *
+         * @param _obj HDLCD that issued the corresponding DMA transaction
+         */
+        DmaDoneEvent(HDLcd *_obj)
+            : Event(), obj(*_obj), transSize(0) {}
+
+        /**
+         * Sets the size of this transaction.
+         *
+         * @param len size of the transaction in bytes
+         */
+        void setTransactionSize(size_t len) {
+            transSize = len;
+        }
+
+        /**
+         * Gets the size of this transaction.
+         *
+         * @return size of this transaction in bytes
+         */
+        size_t getTransactionSize() const {
+            return transSize;
+        }
+
+        void process() {
+            obj.dmaDone(this);
+        }
+
+        const std::string name() const {
+            return obj.name() + ".DmaDoneEvent";
+        }
+    };
+
+    /** Start time for frame buffer dma read */
+    Tick frameReadStartTime;
+
+    /** Starting address for the current frame */
+    Addr dmaStartAddr;
+
+    /** Next address the dma should read from */
+    Addr dmaCurAddr;
+
+    /** One byte past the address of the last byte the dma should read
+      * from */
+    Addr dmaMaxAddr;
+
+    /** Number of pending dma reads */
+    size_t dmaPendingNum;
+
+    /** Flag indicating whether current frame has underrun */
+    bool frameUnderrun;
+
+    /** HDLcd virtual display buffer */
+    uint8_t *virtualDisplayBuffer;
+
+    /** Size of the pixel buffer */
+    size_t pixelBufferSize;
+
+    /** Index of the next pixel to render */
+    size_t pixelIndex;
+
+    /** Flag indicating whether video parameters need updating */
+    bool doUpdateParams;
+
+    /** Flag indicating whether a frame read / display is in progress */
+    bool frameUnderway;
+
+    /**
+     * Number of bytes in flight from DMA that have not reached the pixel
+     * buffer yet
+     */
+    uint32_t dmaBytesInFlight;
+
+    /**
+     * Gets the number of oustanding DMA transactions allowed on the bus at a
+     * time.
+     *
+     * @return gets the driver-specified number of outstanding DMA transactions
+     *         from the hdlcd controller that are allowed on the bus at a time
+     */
+    inline uint16_t maxOutstandingDma() const {
+        return bus_options.max_outstanding;
+    }
+
+    /**
+     * Gets the number of bytes free in the pixel buffer.
+     *
+     * @return number of bytes free in the internal pixel buffer
+     */
+    inline uint32_t bytesFreeInPixelBuffer() const {
+        return PIXEL_BUFFER_CAPACITY - (pixelBufferSize + dmaBytesInFlight);
+    }
+
+    /**
+     * Gets the number of beats-per-burst for bus transactions.
+     *
+     * @return number of beats-per-burst per HDLcd DMA transaction
+     */
+    inline size_t dmaBurstLength() const {
+        assert(bus_options.burst_len <= MAX_BURST_LEN);
+        return bus_options.burst_len;
+    }
+
+    /**
+     * Gets the number of bytes per pixel.
+     *
+     * @return bytes per pixel
+     */
+    inline size_t bytesPerPixel() const {
+        return pixel_format.bytes_per_pixel + 1;
+    }
+
+    /**
+     * Gets frame buffer width.
+     *
+     * @return frame buffer width (pixels per line)
+     */
+    inline size_t width() const {
+        return fb_line_length / bytesPerPixel();
+    }
+
+    /**
+     * Gets frame buffer height.
+     *
+     * @return frame buffer height (lines per panel)
+     */
+    inline size_t height() const {
+        return fb_line_count.fb_line_count;
+    }
+
+    /**
+     * Gets the total number of pixel clocks per display line.
+     *
+     * @return number of pixel clocks per display line including porch delays
+     *         and horizontal sync time
+     */
+    inline uint64_t PClksPerLine() const {
+        return h_back_porch.val + 1 +
+               h_data.val + 1 +
+               h_front_porch.val + 1 +
+               h_sync.val + 1;
+    }
+
+    /** Send updated parameters to the vnc server */
+    void updateVideoParams(bool unserializing);
+
+    /** Generates an interrupt */
+    void generateInterrupt();
+
+    /** Start reading the next frame */
+    void startFrame();
+
+    /** End of frame reached */
+    void endFrame();
+
+    /** Generate DMA read requests from frame buffer into pixel buffer */
+    void fillPixelBuffer();
+
+    /** DMA done event */
+    void dmaDone(DmaDoneEvent *event);
+
+    /** Called when it is time to render a pixel */
+    void renderPixel();
+
+    /** Start of frame event */
+    EventWrapper<HDLcd, &HDLcd::startFrame> startFrameEvent;
+
+    /** End of frame event */
+    EventWrapper<HDLcd, &HDLcd::endFrame> endFrameEvent;
+
+    /** Pixel render event */
+    EventWrapper<HDLcd, &HDLcd::renderPixel> renderPixelEvent;
+
+    /** Fill fifo */
+    EventWrapper<HDLcd, &HDLcd::fillPixelBuffer> fillPixelBufferEvent;
+
+    /** Wrapper to create an event out of the interrupt */
+    EventWrapper<HDLcd, &HDLcd::generateInterrupt> intEvent;
+
+    /**@{*/
+    /**
+     * All pre-allocated DMA done events
+     *
+     * The HDLCD model preallocates maxOutstandingDma() number of
+     * DmaDoneEvents to avoid having to heap allocate every single
+     * event when it is needed. In order to keep track of which events
+     * are in flight and which are ready to be used, we use two
+     * different vectors. dmaDoneEventAll contains <i>all</i>
+     * DmaDoneEvents that the object may use, while dmaDoneEventFree
+     * contains a list of currently <i>unused</i> events. When an
+     * event needs to be scheduled, the last element of the
+     * dmaDoneEventFree is used and removed from the list. When an
+     * event fires, it is added to the end of the
+     * dmaEventFreeList. dmaDoneEventAll is never used except for in
+     * initialization and serialization.
+     */
+    std::vector<DmaDoneEvent> dmaDoneEventAll;
+
+    /** Unused DMA done events that are ready to be scheduled */
+    std::vector<DmaDoneEvent *> dmaDoneEventFree;
+    /**@}*/
+
+  public:
+    typedef HDLcdParams Params;
+
+    const Params *
+    params() const
+    {
+        return dynamic_cast<const Params *>(_params);
+    }
+    HDLcd(const Params *p);
+    ~HDLcd();
+
+    virtual Tick read(PacketPtr pkt);
+    virtual Tick write(PacketPtr pkt);
+
+    virtual void serialize(std::ostream &os);
+    virtual void unserialize(Checkpoint *cp, const std::string &section);
+
+    /**
+     * Determine the address ranges that this device responds to.
+     *
+     * @return a list of non-overlapping address ranges
+     */
+    AddrRangeList getAddrRanges() const;
+};
+
+#endif