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authorwdenk <wdenk>2003-03-27 12:09:35 +0000
committerwdenk <wdenk>2003-03-27 12:09:35 +0000
commitc021880ac5837154ca51b9d84e6b75f39b64aabe (patch)
tree5f9c3cce4dd7b49e69ec5007f58c9b9a2f215c15 /cpu/mips/start.S
parentac6dbb85b7f080d923013bff4e1d5267cb6f8a5a (diff)
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* Add support for MIPS32 4Kc CPUs
* Add support for INCA-IP Board
Diffstat (limited to 'cpu/mips/start.S')
-rw-r--r--cpu/mips/start.S350
1 files changed, 350 insertions, 0 deletions
diff --git a/cpu/mips/start.S b/cpu/mips/start.S
new file mode 100644
index 0000000..bf11655
--- /dev/null
+++ b/cpu/mips/start.S
@@ -0,0 +1,350 @@
+/*
+ * Startup Code for MIPS32 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 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>
+#include <asm/regdef.h>
+#include <asm/mipsregs.h>
+
+
+#define RVECENT(f,n) \
+ b f; nop
+#define XVECENT(f,bev) \
+ b f ; \
+ li k0,bev
+
+ .set noreorder
+
+ .globl _start
+ .text
+_start:
+ RVECENT(reset,0) /* U-boot entry point */
+ RVECENT(reset,1) /* software reboot */
+#ifdef CONFIG_INCA_IP
+ .word 0x000020C4 /* EBU init code, fetched during booting */
+ .word 0x00000000 /* phase of the flash */
+#else
+ RVECENT(romReserved,2)
+#endif
+ RVECENT(romReserved,3)
+ RVECENT(romReserved,4)
+ RVECENT(romReserved,5)
+ RVECENT(romReserved,6)
+ RVECENT(romReserved,7)
+ RVECENT(romReserved,8)
+ RVECENT(romReserved,9)
+ RVECENT(romReserved,10)
+ RVECENT(romReserved,11)
+ RVECENT(romReserved,12)
+ RVECENT(romReserved,13)
+ RVECENT(romReserved,14)
+ RVECENT(romReserved,15)
+ RVECENT(romReserved,16)
+ RVECENT(romReserved,17)
+ RVECENT(romReserved,18)
+ RVECENT(romReserved,19)
+ RVECENT(romReserved,20)
+ RVECENT(romReserved,21)
+ RVECENT(romReserved,22)
+ RVECENT(romReserved,23)
+ RVECENT(romReserved,24)
+ RVECENT(romReserved,25)
+ RVECENT(romReserved,26)
+ RVECENT(romReserved,27)
+ RVECENT(romReserved,28)
+ RVECENT(romReserved,29)
+ RVECENT(romReserved,30)
+ RVECENT(romReserved,31)
+ RVECENT(romReserved,32)
+ RVECENT(romReserved,33)
+ RVECENT(romReserved,34)
+ RVECENT(romReserved,35)
+ RVECENT(romReserved,36)
+ RVECENT(romReserved,37)
+ RVECENT(romReserved,38)
+ RVECENT(romReserved,39)
+ RVECENT(romReserved,40)
+ RVECENT(romReserved,41)
+ RVECENT(romReserved,42)
+ RVECENT(romReserved,43)
+ RVECENT(romReserved,44)
+ RVECENT(romReserved,45)
+ RVECENT(romReserved,46)
+ RVECENT(romReserved,47)
+ RVECENT(romReserved,48)
+ RVECENT(romReserved,49)
+ RVECENT(romReserved,50)
+ RVECENT(romReserved,51)
+ RVECENT(romReserved,52)
+ RVECENT(romReserved,53)
+ RVECENT(romReserved,54)
+ RVECENT(romReserved,55)
+ RVECENT(romReserved,56)
+ RVECENT(romReserved,57)
+ RVECENT(romReserved,58)
+ RVECENT(romReserved,59)
+ RVECENT(romReserved,60)
+ RVECENT(romReserved,61)
+ RVECENT(romReserved,62)
+ RVECENT(romReserved,63)
+ XVECENT(romExcHandle,0x200) /* bfc00200: R4000 tlbmiss vector */
+ RVECENT(romReserved,65)
+ RVECENT(romReserved,66)
+ RVECENT(romReserved,67)
+ RVECENT(romReserved,68)
+ RVECENT(romReserved,69)
+ RVECENT(romReserved,70)
+ RVECENT(romReserved,71)
+ RVECENT(romReserved,72)
+ RVECENT(romReserved,73)
+ RVECENT(romReserved,74)
+ RVECENT(romReserved,75)
+ RVECENT(romReserved,76)
+ RVECENT(romReserved,77)
+ RVECENT(romReserved,78)
+ RVECENT(romReserved,79)
+ XVECENT(romExcHandle,0x280) /* bfc00280: R4000 xtlbmiss vector */
+ RVECENT(romReserved,81)
+ RVECENT(romReserved,82)
+ RVECENT(romReserved,83)
+ RVECENT(romReserved,84)
+ RVECENT(romReserved,85)
+ RVECENT(romReserved,86)
+ RVECENT(romReserved,87)
+ RVECENT(romReserved,88)
+ RVECENT(romReserved,89)
+ RVECENT(romReserved,90)
+ RVECENT(romReserved,91)
+ RVECENT(romReserved,92)
+ RVECENT(romReserved,93)
+ RVECENT(romReserved,94)
+ RVECENT(romReserved,95)
+ XVECENT(romExcHandle,0x300) /* bfc00300: R4000 cache vector */
+ RVECENT(romReserved,97)
+ RVECENT(romReserved,98)
+ RVECENT(romReserved,99)
+ RVECENT(romReserved,100)
+ RVECENT(romReserved,101)
+ RVECENT(romReserved,102)
+ RVECENT(romReserved,103)
+ RVECENT(romReserved,104)
+ RVECENT(romReserved,105)
+ RVECENT(romReserved,106)
+ RVECENT(romReserved,107)
+ RVECENT(romReserved,108)
+ RVECENT(romReserved,109)
+ RVECENT(romReserved,110)
+ RVECENT(romReserved,111)
+ XVECENT(romExcHandle,0x380) /* bfc00380: R4000 general vector */
+ RVECENT(romReserved,113)
+ RVECENT(romReserved,114)
+ RVECENT(romReserved,115)
+ RVECENT(romReserved,116)
+ RVECENT(romReserved,116)
+ RVECENT(romReserved,118)
+ RVECENT(romReserved,119)
+ RVECENT(romReserved,120)
+ RVECENT(romReserved,121)
+ RVECENT(romReserved,122)
+ RVECENT(romReserved,123)
+ RVECENT(romReserved,124)
+ RVECENT(romReserved,125)
+ RVECENT(romReserved,126)
+ RVECENT(romReserved,127)
+
+ /* We hope there are no more reserved vectors!
+ * 128 * 8 == 1024 == 0x400
+ * so this is address R_VEC+0x400 == 0xbfc00400
+ */
+ .align 4
+reset:
+
+ /* Clear watch registers.
+ */
+ mtc0 zero, CP0_WATCHLO
+ mtc0 zero, CP0_WATCHHI
+
+ /* STATUS register */
+ mfc0 k0, CP0_STATUS
+ li k1, ~ST0_IE
+ and k0, k1
+ mtc0 k0, CP0_STATUS
+
+ /* CAUSE register */
+ mtc0 zero, CP0_CAUSE
+
+ /* Init Timer */
+ mtc0 zero, CP0_COUNT
+ mtc0 zero, CP0_COMPARE
+
+ /* CONFIG0 register */
+ li t0, CONF_CM_UNCACHED
+ mtc0 t0, CP0_CONFIG
+
+#ifdef CONFIG_INCA_IP
+ /* Disable INCA-IP Watchdog.
+ */
+ bal disable_incaip_wdt
+ nop
+#endif
+
+ /* Initialize any external memory.
+ */
+ bal memsetup
+ nop
+
+ /* Initialize caches...
+ */
+ bal mips_cache_reset
+ nop
+
+ /* ... and enable them.
+ */
+ li t0, CONF_CM_CACHABLE_NONCOHERENT
+ mtc0 t0, CP0_CONFIG
+
+
+ /* Set up temporary stack.
+ */
+ li a0, CFG_INIT_SP_OFFSET
+ bal mips_cache_lock
+ nop
+
+ li t0, CFG_SDRAM_BASE + CFG_INIT_SP_OFFSET
+ la sp, 0(t0)
+
+ /* Initialize GOT pointer.
+ */
+ bal 1f
+ nop
+ .word _GLOBAL_OFFSET_TABLE_ - 1f + 4
+1:
+ move gp, ra
+ lw t1, 0(ra)
+ add gp, t1
+ la t9, board_init_f
+ j 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 */
+
+ /*
+ * Fix GOT pointer:
+ *
+ * New GOT-PTR = (old GOT-PTR - CFG_MONITOR_BASE) + Destination Address
+ */
+ move t6, gp
+ sub gp, CFG_MONITOR_BASE
+ add gp, a2 /* gp now adjusted */
+ sub t6, gp, t6 /* t6 <-- relocation offset */
+
+ li t0, CFG_MONITOR_BASE
+ add t2, t0, CFG_MONITOR_LEN
+ move t1, a2
+
+ /*
+ * t0 = source address
+ * t1 = target address
+ * t2 = source end address
+ */
+1:
+ lw t3, 0(t0)
+ sw t3, 0(t1)
+ addu t0, 4
+ ble t0, t2, 1b
+ addu t1, 4 /* delay slot */
+
+ /* If caches were enabled, we would have to flush them here.
+ */
+
+ /* Jump to where we've relocated ourselves.
+ */
+ addi t0, a2, in_ram - _start
+ j t0
+ nop
+
+ .word uboot_end_data
+ .word uboot_end
+ .word num_got_entries
+
+in_ram:
+ /* Now we want to update GOT.
+ */
+ lw t3, -4(t0) /* t3 <-- num_got_entries */
+ addi t4, gp, 8 /* Skipping first two entries. */
+ li t2, 2
+1:
+ lw t1, 0(t4)
+ beqz t1, 2f
+ add t1, t6
+ sw t1, 0(t4)
+2:
+ addi t2, 1
+ blt t2, t3, 1b
+ addi t4, 4 /* delay slot */
+
+ /* Clear BSS.
+ */
+ lw t1, -12(t0) /* t1 <-- uboot_end_data */
+ lw t2, -8(t0) /* t2 <-- uboot_end */
+ add t1, t6 /* adjust pointers */
+ add t2, t6
+
+ sub t1, 4
+1: addi t1, 4
+ bltl t1, t2, 1b
+ sw zero, 0(t1) /* delay slot */
+
+ move a0, a1
+ la t9, board_init_r
+ j t9
+ move a1, a2 /* delay slot */
+
+ .end relocate_code
+
+
+
+ /* Exception handlers.
+ */
+romReserved:
+ b romReserved
+
+romExcHandle:
+ b romExcHandle
+