From 9dd54d10ab63c395b84bff31b5ff94b35c44e18f Mon Sep 17 00:00:00 2001 From: Sudhanshu Jha Date: Fri, 24 Feb 2017 13:34:22 +0000 Subject: [PATCH] dev: Add support for single-pass scan out in the PixelPump Add a helper function to scan out an entire frame in one time step. This requires the public PixelPump to be changed somewhat to separate timing updates from general PixelPump control. Instead of calling PixelPump::start(timings), timings now need to be updated using a separate call to PixelPump::updateTimings(timings) before calling PixelPump::start(). Display controllers that don't need accurate timing (e.g., in KVM mode), can use the new PixelPump::renderFrame() API to render an entire frame in one step. This call results in the same callbacks (e.g., calls to nextPixel()) as the timing calls, but they all happen in immediately. Unlike the timing counterpart, renderFrame() doesn't support buffer underruns and will panic if nextPixle() indicates an underrun. Change-Id: I76c84db04249b02d4207c5281d82aa693d0881be Signed-off-by: Andreas Sandberg Reviewed-on: https://gem5-review.googlesource.com/2241 Reviewed-by: Rahul Thakur Reviewed-by: Jason Lowe-Power --- src/dev/arm/hdlcd.cc | 14 +++++++--- src/dev/pixelpump.cc | 61 +++++++++++++++++++++++++++++++++++++++++--- src/dev/pixelpump.hh | 18 ++++++++++--- 3 files changed, 82 insertions(+), 11 deletions(-) diff --git a/src/dev/arm/hdlcd.cc b/src/dev/arm/hdlcd.cc index 363aeba94..a92ae4627 100644 --- a/src/dev/arm/hdlcd.cc +++ b/src/dev/arm/hdlcd.cc @@ -1,5 +1,5 @@ /* - * Copyright (c) 2010-2013, 2015 ARM Limited + * Copyright (c) 2010-2013, 2015, 2017 ARM Limited * All rights reserved * * The license below extends only to copyright in the software and shall @@ -204,8 +204,11 @@ HDLcd::drainResume() // We restored from an old checkpoint without a pixel pump, start // an new refresh. This typically happens when restoring from old // checkpoints. - if (enabled() && !pixelPump.active()) - pixelPump.start(displayTimings()); + if (enabled() && !pixelPump.active()) { + // Update timing parameter before rendering frames + pixelPump.updateTimings(displayTimings()); + pixelPump.start(); + } // We restored from a checkpoint and need to update the VNC server if (pixelPump.active() && vnc) @@ -476,7 +479,10 @@ HDLcd::cmdEnable() { createDmaEngine(); conv = pixelConverter(); - pixelPump.start(displayTimings()); + + // Update timing parameter before rendering frames + pixelPump.updateTimings(displayTimings()); + pixelPump.start(); } void diff --git a/src/dev/pixelpump.cc b/src/dev/pixelpump.cc index 3ffe96d96..e1cf73af6 100644 --- a/src/dev/pixelpump.cc +++ b/src/dev/pixelpump.cc @@ -1,5 +1,5 @@ /* - * Copyright (c) 2015 ARM Limited + * Copyright (c) 2015, 2017 ARM Limited * All rights reserved * * The license below extends only to copyright in the software and shall @@ -136,10 +136,11 @@ BasePixelPump::unserialize(CheckpointIn &cp) event->unserializeSection(cp, event->name()); } - void -BasePixelPump::start(const DisplayTimings &timings) +BasePixelPump::updateTimings(const DisplayTimings &timings) { + panic_if(active(), "Trying to update timings in active PixelPump\n"); + _timings = timings; // Resize the frame buffer if needed @@ -149,9 +150,15 @@ BasePixelPump::start(const DisplayTimings &timings) // Set the current line past the last line in the frame. This // triggers the new frame logic in beginLine(). line = _timings.linesPerFrame(); +} + +void +BasePixelPump::start() +{ schedule(evBeginLine, clockEdge()); } + void BasePixelPump::stop() { @@ -241,6 +248,54 @@ BasePixelPump::renderPixels() } } +void +BasePixelPump::renderFrame() +{ + _underrun = false; + line = 0; + + // Signal vsync end and render the frame + line = _timings.lineVBackPorchStart(); + onVSyncEnd(); + + // We only care about the visible screen area when rendering the + // frame + for (line = _timings.lineFirstVisible(); + line < _timings.lineFrontPorchStart(); + ++line) { + + _posX = 0; + + onHSyncBegin(); + onHSyncEnd(); + + renderLine(); + } + + line = _timings.lineFrontPorchStart() - 1; + onFrameDone(); + + // Signal vsync until the next frame begins + line = _timings.lineVSyncStart(); + onVSyncBegin(); +} + +void +BasePixelPump::renderLine() +{ + const unsigned pos_y(posY()); + + Pixel pixel(0, 0, 0); + for (_posX = 0; _posX < _timings.width; ++_posX) { + if (!nextPixel(pixel)) { + panic("Unexpected underrun in BasePixelPump (%u, %u)\n", + _posX, pos_y); + } + fb.pixel(_posX, pos_y) = pixel; + } +} + + BasePixelPump::PixelEvent::PixelEvent( const char *name, BasePixelPump *_parent, CallbackType _func) : Event(), Drainable(), diff --git a/src/dev/pixelpump.hh b/src/dev/pixelpump.hh index 159ee79cb..bc21fca75 100644 --- a/src/dev/pixelpump.hh +++ b/src/dev/pixelpump.hh @@ -1,5 +1,5 @@ /* - * Copyright (c) 2015 ARM Limited + * Copyright (c) 2015, 2017 ARM Limited * All rights reserved * * The license below extends only to copyright in the software and shall @@ -148,15 +148,22 @@ class BasePixelPump public Serializable { public: - BasePixelPump(EventManager &em, ClockDomain &pxl_clk, unsigned pixel_chunk); + BasePixelPump(EventManager &em, ClockDomain &pxl_clk, + unsigned pixel_chunk); virtual ~BasePixelPump(); void serialize(CheckpointOut &cp) const override; void unserialize(CheckpointIn &cp) override; public: // Public API - /** Starting pushing pixels using the supplied display timings. */ - void start(const DisplayTimings &timings); + /** Update frame size using display timing */ + void updateTimings(const DisplayTimings &timings); + + /** Render an entire frame in KVM execution mode */ + void renderFrame(); + + /** Starting pushing pixels in timing mode */ + void start(); /** Immediately stop pushing pixels */ void stop(); @@ -285,6 +292,9 @@ class BasePixelPump void beginLine(); void renderPixels(); + /** Fast and event-free line rendering function */ + void renderLine(); + /** Convenience vector when doing operations on all events */ std::vector pixelEvents;