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-rw-r--r--arch/arm/boards/edb93xx/early_udelay.h34
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diff --git a/arch/arm/boards/edb93xx/early_udelay.h b/arch/arm/boards/edb93xx/early_udelay.h
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+/*
+ * Copyright (C) 2009 Matthias Kaehlcke <matthias@kaehlcke.net>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * 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., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+
+/* delay execution before timers are initialized */
+static inline void early_udelay(uint32_t usecs)
+{
+ /* loop takes 4 cycles at 5.0ns (fastest case, running at 200MHz) */
+ register uint32_t loops = usecs * (1000 / 20);
+
+ __asm__ volatile ("1:\n"
+ "subs %0, %1, #1\n"
+ "bne 1b":"=r" (loops):"0" (loops));
+}