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-rw-r--r--board/gcplus/memsetup.S77
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diff --git a/board/gcplus/memsetup.S b/board/gcplus/memsetup.S
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+/*
+ * Memory Setup stuff - taken from blob memsetup.S
+ *
+ * Copyright (C) 1999 2000 2001 Erik Mouw (J.A.K.Mouw@its.tudelft.nl) and
+ * Jan-Derk Bakker (J.D.Bakker@its.tudelft.nl)
+ * 2003-2004 (c) MontaVista Software, Inc.
+ *
+ * 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 "config.h"
+#include "version.h"
+
+
+ .globl memsetup
+memsetup:
+ /* The ADS GC+ for Linux Boot Rom Ver. 1.73 does memory init for us.
+ * However the darn thing leaves the MMU enabled before handing control
+ * over to us. So we need to disable the MMU and we use memsetup
+ * to do it.
+ */
+
+@ The following code segment was borrowed with gratitude from:
+@ linux-2.4.19-rmk7/arch/arm/boot/compressed/head-sa1100.S
+
+ @ Data cache might be active.
+ @ Be sure to flush kernel binary out of the cache,
+ @ whatever state it is, before it is turned off.
+ @ This is done by fetching through currently executed
+ @ memory to be sure we hit the same cache.
+ bic r2, pc, #0x1f
+ add r3, r2, #0x4000 @ 16 kb is quite enough...
+1: ldr r0, [r2], #32
+ teq r2, r3
+ bne 1b
+ mcr p15, 0, r0, c7, c10, 4 @ drain WB
+ mcr p15, 0, r0, c7, c7, 0 @ flush I & D caches
+
+ @ disabling MMU and caches
+ mrc p15, 0, r0, c1, c0, 0 @ read control reg
+ bic r0, r0, #0x0d @ clear WB, DC, MMU
+ bic r0, r0, #0x1000 @ clear Icache
+ mcr p15, 0, r0, c1, c0, 0
+
+ nop
+ nop
+ nop
+ nop
+ nop
+
+ b 2f
+2:
+ nop
+ nop
+ nop
+ nop
+ nop
+
+
+ mov pc, lr