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-rw-r--r--include/asm-arm/macro.h74
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diff --git a/include/asm-arm/macro.h b/include/asm-arm/macro.h
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+/*
+ * include/asm-arm/macro.h
+ *
+ * Copyright (C) 2009 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
+ *
+ * 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
+ */
+
+#ifndef __ASM_ARM_MACRO_H__
+#define __ASM_ARM_MACRO_H__
+#ifdef __ASSEMBLY__
+
+/*
+ * These macros provide a convenient way to write 8, 16 and 32 bit data
+ * to any address.
+ * Registers r4 and r5 are used, any data in these registers are
+ * overwritten by the macros.
+ * The macros are valid for any ARM architecture, they do not implement
+ * any memory barriers so caution is recommended when using these when the
+ * caches are enabled or on a multi-core system.
+ */
+
+.macro write32, addr, data
+ ldr r4, =\addr
+ ldr r5, =\data
+ str r5, [r4]
+.endm
+
+.macro write16, addr, data
+ ldr r4, =\addr
+ ldrh r5, =\data
+ strh r5, [r4]
+.endm
+
+.macro write8, addr, data
+ ldr r4, =\addr
+ ldrb r5, =\data
+ strb r5, [r4]
+.endm
+
+/*
+ * This macro generates a loop that can be used for delays in the code.
+ * Register r4 is used, any data in this register is overwritten by the
+ * macro.
+ * The macro is valid for any ARM architeture. The actual time spent in the
+ * loop will vary from CPU to CPU though.
+ */
+
+.macro wait_timer, time
+ ldr r4, =\time
+1:
+ nop
+ subs r4, r4, #1
+ bcs 1b
+.endm
+
+#endif /* __ASSEMBLY__ */
+#endif /* __ASM_ARM_MACRO_H__ */