mips: Add mips/ashldi3.c from Linux

As MIPS toolchain does not provide adequate support for 64 bit
division and shift operations, the missing functions are required to
be provided by the user.

This patch brings in the Linux implementation of the 64 bit arithmetic
shift borrowed from arch/mips/lib/ashldi3.c (eg. Linux v3.14).

BUG=chromium:406038
TEST=With the upcoming patches coreboot successfully builds for MIPS
     targets in chroot (coming later).

Change-Id: I2168f69352a9b9e3c5d197489f701a442e65703c
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: 8ec616161be8ad3aeb6494e7121615e3329b414d
Original-Change-Id: Ia1ccb29d4c9f3c95e04e06f6af7ce8a00e2e7455
Original-Signed-off-by: Vadim Bendebury <vbendeb@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/214156
Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/8759
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <pgeorgi@google.com>

1 files changed, 60 insertions, 0 deletions

diff --git a/src/arch/mips/ashldi3.c b/src/arch/mips/ashldi3.c
new file mode 100644
index 0000000000..caa69fa3e1
--- /dev/null
+++ b/src/arch/mips/ashldi3.c
@@ -0,0 +1,60 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2014 Google, Inc.
+ *
+ * Based on linux arch/mips/lib/ashldi3.c
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
+ */
+
+#ifndef __ORDER_LITTLE_ENDIAN__
+#errror "What endian are you!?"
+#endif
+
+typedef unsigned word_type;
+long long __ashldi3(long long u, word_type b);
+
+struct DWstruct {
+	int low, high;
+};
+typedef union {
+	struct DWstruct s;
+	long long ll;
+} DWunion;
+
+long long __ashldi3(long long u, word_type b)
+{
+	DWunion uu, w;
+	word_type bm;
+
+	if (b == 0)
+		return u;
+
+	uu.ll = u;
+	bm = 32 - b;
+
+	if (bm <= 0) {
+		w.s.low = 0;
+		w.s.high = (unsigned int) uu.s.low << -bm;
+	} else {
+		const unsigned int carries = (unsigned int) uu.s.low >> bm;
+
+		w.s.low = (unsigned int) uu.s.low << b;
+		w.s.high = ((unsigned int) uu.s.high << b) | carries;
+	}
+
+	return w.ll;
+}
+