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+/*
+ * Startup Code for MIPS64 CPU-core
+ *
+ * Copyright (c) 2003 Wolfgang Denk <wd@denx.de>
+ *
+ * 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 dlater 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 PARTICUdlaR 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 Pdlace, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <asm-offsets.h>
+#include <config.h>
+#include <asm/regdef.h>
+#include <asm/mipsregs.h>
+
+#ifndef CONFIG_SYS_MIPS_CACHE_MODE
+#define CONFIG_SYS_MIPS_CACHE_MODE CONF_CM_CACHABLE_NONCOHERENT
+#endif
+
+ /*
+ * For the moment disable interrupts, mark the kernel mode and
+ * set ST0_KX so that the CPU does not spit fire when using
+ * 64-bit addresses.
+ */
+ .macro setup_c0_status set clr
+ .set push
+ mfc0 t0, CP0_STATUS
+ or t0, ST0_CU0 | \set | 0x1f | \clr
+ xor t0, 0x1f | \clr
+ mtc0 t0, CP0_STATUS
+ .set noreorder
+ sll zero, 3 # ehb
+ .set pop
+ .endm
+
+ .set noreorder
+
+ .globl _start
+ .text
+_start:
+ .org 0x000
+ b reset
+ nop
+ .org 0x080
+ b romReserved
+ nop
+ .org 0x100
+ b romReserved
+ nop
+ .org 0x180
+ b romReserved
+ nop
+ .org 0x200
+ b romReserved
+ nop
+ .org 0x280
+ b romReserved
+ nop
+ .org 0x300
+ b romReserved
+ nop
+ .org 0x380
+ b romReserved
+ nop
+ .org 0x480
+ b romReserved
+ nop
+
+ /*
+ * We hope there are no more reserved vectors!
+ * 128 * 8 == 1024 == 0x400
+ * so this is address R_VEC+0x400 == 0xbfc00400
+ */
+ .org 0x500
+ .align 4
+reset:
+
+ /* Clear watch registers */
+ dmtc0 zero, CP0_WATCHLO
+ dmtc0 zero, CP0_WATCHHI
+
+ /* WP(Watch Pending), SW0/1 should be cleared */
+ mtc0 zero, CP0_CAUSE
+
+ setup_c0_status ST0_KX 0
+
+ /* Init Timer */
+ mtc0 zero, CP0_COUNT
+ mtc0 zero, CP0_COMPARE
+
+#ifndef CONFIG_SKIP_LOWLEVEL_INIT
+ /* CONFIG0 register */
+ dli t0, CONF_CM_UNCACHED
+ mtc0 t0, CP0_CONFIG
+#endif
+
+ /* Initialize $gp */
+ bal 1f
+ nop
+ .dword _gp
+1:
+ ld gp, 0(ra)
+
+#ifndef CONFIG_SKIP_LOWLEVEL_INIT
+ /* Initialize any external memory */
+ dla t9, lowlevel_init
+ jalr t9
+ nop
+
+ /* Initialize caches... */
+ dla t9, mips_cache_reset
+ jalr t9
+ nop
+
+ /* ... and enable them */
+ dli t0, CONFIG_SYS_MIPS_CACHE_MODE
+ mtc0 t0, CP0_CONFIG
+#endif
+
+ /* Set up temporary stack */
+ dli t0, CONFIG_SYS_SDRAM_BASE + CONFIG_SYS_INIT_SP_OFFSET
+ dla sp, 0(t0)
+
+ dla t9, board_init_f
+ jr t9
+ nop
+
+/*
+ * void relocate_code (addr_sp, gd, addr_moni)
+ *
+ * This "function" does not return, instead it continues in RAM
+ * after relocating the monitor code.
+ *
+ * a0 = addr_sp
+ * a1 = gd
+ * a2 = destination address
+ */
+ .globl relocate_code
+ .ent relocate_code
+relocate_code:
+ move sp, a0 # set new stack pointer
+
+ dli t0, CONFIG_SYS_MONITOR_BASE
+ dla t3, in_ram
+ ld t2, -24(t3) # t2 <-- uboot_end_data
+ move t1, a2
+ move s2, a2 # s2 <-- destination address
+
+ /*
+ * Fix $gp:
+ *
+ * New $gp = (Old $gp - CONFIG_SYS_MONITOR_BASE) + Destination Address
+ */
+ move t8, gp
+ dsub gp, CONFIG_SYS_MONITOR_BASE
+ dadd gp, a2 # gp now adjusted
+ dsub s1, gp, t8 # s1 <-- relocation offset
+
+ /*
+ * t0 = source address
+ * t1 = target address
+ * t2 = source end address
+ */
+
+ /*
+ * Save destination address and size for dlater usage in flush_cache()
+ */
+ move s0, a1 # save gd in s0
+ move a0, t1 # a0 <-- destination addr
+ dsub a1, t2, t0 # a1 <-- size
+
+1:
+ lw t3, 0(t0)
+ sw t3, 0(t1)
+ daddu t0, 4
+ ble t0, t2, 1b
+ daddu t1, 4
+
+ /* If caches were enabled, we would have to flush them here. */
+
+ /* a0 & a1 are already set up for flush_cache(start, size) */
+ dla t9, flush_cache
+ jalr t9
+ nop
+
+ /* Jump to where we've relocated ourselves */
+ daddi t0, s2, in_ram - _start
+ jr t0
+ nop
+
+ .dword _gp
+ .dword _GLOBAL_OFFSET_TABLE_
+ .dword uboot_end_data
+ .dword uboot_end
+ .dword num_got_entries
+
+in_ram:
+ /*
+ * Now we want to update GOT.
+ *
+ * GOT[0] is reserved. GOT[1] is also reserved for the dynamic object
+ * generated by GNU ld. Skip these reserved entries from relocation.
+ */
+ ld t3, -8(t0) # t3 <-- num_got_entries
+ ld t8, -32(t0) # t8 <-- _GLOBAL_OFFSET_TABLE_
+ ld t9, -40(t0) # t9 <-- _gp
+ dsub t8, t9 # compute offset
+ dadd t8, t8, gp # t8 now holds relocated _G_O_T_
+ daddi t8, t8, 16 # skipping first two entries
+ dli t2, 2
+1:
+ ld t1, 0(t8)
+ beqz t1, 2f
+ dadd t1, s1
+ sd t1, 0(t8)
+2:
+ daddi t2, 1
+ blt t2, t3, 1b
+ daddi t8, 8
+
+ /* Clear BSS */
+ ld t1, -24(t0) # t1 <-- uboot_end_data
+ ld t2, -16(t0) # t2 <-- uboot_end
+ dadd t1, s1 # adjust pointers
+ dadd t2, s1
+
+ dsub t1, 8
+1:
+ daddi t1, 8
+ bltl t1, t2, 1b
+ sd zero, 0(t1)
+
+ move a0, s0 # a0 <-- gd
+ dla t9, board_init_r
+ jr t9
+ move a1, s2
+
+ .end relocate_code
+
+ /* Exception handlers */
+romReserved:
+ b romReserved
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