base: Split out the pixel class in framebuffer.(cc|hh).

These are really two separate things. Also, while it's realitively
straightforward to write a unit test for the pixel conversion code, the
framebuffer object is serializable and brings in more dependencies.

Change-Id: If954caeb0bfedb1002cfb1a7a115a00c90d56d19
Reviewed-on: https://gem5-review.googlesource.com/6341
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

1 files changed, 100 insertions, 0 deletions

diff --git a/src/base/pixel.cc b/src/base/pixel.cc
new file mode 100644
index 000000000..29dcaf68f
--- /dev/null
+++ b/src/base/pixel.cc
@@ -0,0 +1,100 @@
+/*
+ * Copyright (c) 2015 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: Andreas Sandberg
+ */
+
+#include "base/pixel.hh"
+
+#include <cassert>
+
+#include "base/bitfield.hh"
+
+const PixelConverter PixelConverter::rgba8888_le(4, 0, 8, 16, 8, 8, 8);
+const PixelConverter PixelConverter::rgba8888_be(4, 0, 8, 16, 8, 8, 8,
+                                                 BigEndianByteOrder);
+const PixelConverter PixelConverter::rgb565_le(2,  0, 5, 11, 5, 6, 5);
+const PixelConverter PixelConverter::rgb565_be(2,  0, 5, 11, 5, 6, 5,
+                                               BigEndianByteOrder);
+
+PixelConverter::PixelConverter(unsigned _length,
+                               unsigned ro, unsigned go, unsigned bo,
+                               unsigned rw, unsigned gw, unsigned bw,
+                               ByteOrder _byte_order)
+    : length(_length),
+      depth(rw + gw + bw),
+      byte_order(_byte_order),
+      ch_r(ro, rw),
+      ch_g(go, gw),
+      ch_b(bo, bw)
+{
+    assert(length > 1);
+}
+
+PixelConverter::Channel::Channel(unsigned _offset, unsigned width)
+    : offset(_offset),
+      mask(::mask(width)),
+      factor(255.0 / mask)
+{
+}
+
+uint32_t
+PixelConverter::readWord(const uint8_t *p) const
+{
+    uint32_t word(0);
+
+    if (byte_order == LittleEndianByteOrder) {
+        for (int i = 0; i < length; ++i)
+            word |= p[i] << (8 * i);
+    } else {
+        for (int i = 0; i < length; ++i)
+            word |= p[i] << (8 * (length - i - 1));
+    }
+
+    return word;
+}
+
+void
+PixelConverter::writeWord(uint8_t *p, uint32_t word) const
+{
+    if (byte_order == LittleEndianByteOrder) {
+        for (int i = 0; i < length; ++i)
+            p[i] = (word >> (8 * i)) & 0xFF;
+    } else {
+        for (int i = 0; i < length; ++i)
+            p[i] = (word >> (8 * (length - i - 1))) & 0xFF;
+    }
+}