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+/*
+ * LZMA compressed kernel loader for Atheros AR7XXX/AR9XXX based boards
+ *
+ * Copyright (C) 2011 Gabor Juhos <juhosg@openwrt.org>
+ *
+ * Some parts of this code was based on the OpenWrt specific lzma-loader
+ * for the BCM47xx and ADM5120 based boards:
+ * Copyright (C) 2004 Manuel Novoa III (mjn3@codepoet.org)
+ * Copyright (C) 2005 by Oleg I. Vdovikin <oleg@cs.msu.su>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ */
+
+#include <asm/asm.h>
+#include <asm/regdef.h>
+#include "cp0regdef.h"
+#include "cacheops.h"
+#include "config.h"
+
+#define KSEG0 0x80000000
+
+ .macro ehb
+ sll zero, 3
+ .endm
+
+ .text
+
+LEAF(startup)
+ .set noreorder
+ .set mips32
+
+ mtc0 zero, CP0_WATCHLO # clear watch registers
+ mtc0 zero, CP0_WATCHHI
+ mtc0 zero, CP0_CAUSE # clear before writing status register
+
+ mfc0 t0, CP0_STATUS
+ li t1, 0x1000001f
+ or t0, t1
+ xori t0, 0x1f
+ mtc0 t0, CP0_STATUS
+ ehb
+
+ mtc0 zero, CP0_COUNT
+ mtc0 zero, CP0_COMPARE
+ ehb
+
+ la t0, __reloc_label # get linked address of label
+ bal __reloc_label # branch and link to label to
+ nop # get actual address
+__reloc_label:
+ subu t0, ra, t0 # get reloc_delta
+
+ beqz t0, __reloc_done # if delta is 0 we are in the right place
+ nop
+
+ /* Copy our code to the right place */
+ la t1, _code_start # get linked address of _code_start
+ la t2, _code_end # get linked address of _code_end
+ addu t0, t0, t1 # calculate actual address of _code_start
+
+__reloc_copy:
+ lw t3, 0(t0)
+ sw t3, 0(t1)
+ add t1, 4
+ blt t1, t2, __reloc_copy
+ add t0, 4
+
+ /* flush cache */
+ la t0, _code_start
+ la t1, _code_end
+
+ li t2, ~(CONFIG_CACHELINE_SIZE - 1)
+ and t0, t2
+ and t1, t2
+ li t2, CONFIG_CACHELINE_SIZE
+
+ b __flush_check
+ nop
+
+__flush_line:
+ cache Hit_Writeback_Inv_D, 0(t0)
+ cache Hit_Invalidate_I, 0(t0)
+ add t0, t2
+
+__flush_check:
+ bne t0, t1, __flush_line
+ nop
+
+ sync
+
+__reloc_done:
+
+ /* clear bss */
+ la t0, _bss_start
+ la t1, _bss_end
+ b __bss_check
+ nop
+
+__bss_fill:
+ sw zero, 0(t0)
+ addi t0, 4
+
+__bss_check:
+ bne t0, t1, __bss_fill
+ nop
+
+ /* Setup new "C" stack */
+ la sp, _stack
+
+ /* jump to the decompressor routine */
+ la t0, loader_main
+ jr t0
+ nop
+
+ .set reorder
+END(startup)