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-rw-r--r--cpu/mips/start.S69
1 files changed, 35 insertions, 34 deletions
diff --git a/cpu/mips/start.S b/cpu/mips/start.S
index e91e213..c92b162 100644
--- a/cpu/mips/start.S
+++ b/cpu/mips/start.S
@@ -22,13 +22,11 @@
* 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) \
@@ -192,7 +190,7 @@ _start:
.word 0x00000000
.word 0x03e00008
.word 0x00000000
- .word 0x00000000
+ .word 0x00000000
/* 0xbfc00428 */
.word 0xdc870000
.word 0xfca70000
@@ -203,7 +201,7 @@ _start:
.word 0x00000000
.word 0x03e00008
.word 0x00000000
- .word 0x00000000
+ .word 0x00000000
#endif /* CONFIG_PURPLE */
.align 4
reset:
@@ -234,34 +232,32 @@ reset:
li t0, CONF_CM_UNCACHED
mtc0 t0, CP0_CONFIG
- /* Initialize GOT pointer.
- */
- bal 1f
+ /* Initialize $gp.
+ */
+ bal 1f
nop
- .word _GLOBAL_OFFSET_TABLE_
- 1:
- move gp, ra
- lw t1, 0(ra)
- move gp, t1
+ .word _gp
+1:
+ lw gp, 0(ra)
#ifdef CONFIG_INCA_IP
/* Disable INCA-IP Watchdog.
*/
- la t9, disable_incaip_wdt
- jalr t9
+ la t9, disable_incaip_wdt
+ jalr t9
nop
#endif
/* Initialize any external memory.
*/
- la t9, lowlevel_init
- jalr t9
+ la t9, lowlevel_init
+ jalr t9
nop
/* Initialize caches...
*/
- la t9, mips_cache_reset
- jalr t9
+ la t9, mips_cache_reset
+ jalr t9
nop
/* ... and enable them.
@@ -269,12 +265,11 @@ reset:
li t0, CONF_CM_CACHABLE_NONCOHERENT
mtc0 t0, CP0_CONFIG
-
/* Set up temporary stack.
*/
li a0, CFG_INIT_SP_OFFSET
- la t9, mips_cache_lock
- jalr t9
+ la t9, mips_cache_lock
+ jalr t9
nop
li t0, CFG_SDRAM_BASE + CFG_INIT_SP_OFFSET
@@ -284,7 +279,6 @@ reset:
j t9
nop
-
/*
* void relocate_code (addr_sp, gd, addr_moni)
*
@@ -298,7 +292,7 @@ reset:
.globl relocate_code
.ent relocate_code
relocate_code:
- move sp, a0 /* Set new stack pointer */
+ move sp, a0 /* Set new stack pointer */
li t0, CFG_MONITOR_BASE
la t3, in_ram
@@ -306,14 +300,14 @@ relocate_code:
move t1, a2
/*
- * Fix GOT pointer:
+ * Fix $gp:
*
- * New GOT-PTR = (old GOT-PTR - CFG_MONITOR_BASE) + Destination Address
+ * New $gp = (Old $gp - 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 */
+ add gp, a2 /* gp now adjusted */
+ sub t6, gp, t6 /* t6 <-- relocation offset */
/*
* t0 = source address
@@ -329,7 +323,7 @@ relocate_code:
sw t3, 0(t1)
addu t0, 4
ble t0, t2, 1b
- addu t1, 4 /* delay slot */
+ addu t1, 4 /* delay slot */
#endif
/* If caches were enabled, we would have to flush them here.
@@ -341,15 +335,22 @@ relocate_code:
j t0
nop
+ .gpword _GLOBAL_OFFSET_TABLE_ /* _GLOBAL_OFFSET_TABLE_ - _gp */
.word uboot_end_data
.word uboot_end
.word num_got_entries
in_ram:
- /* Now we want to update GOT.
+ /*
+ * 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.
*/
lw t3, -4(t0) /* t3 <-- num_got_entries */
- addi t4, gp, 8 /* Skipping first two entries. */
+ lw t4, -16(t0) /* t4 <-- (_GLOBAL_OFFSET_TABLE_ - _gp) */
+ add t4, t4, gp /* t4 now holds _GLOBAL_OFFSET_TABLE_ */
+ addi t4, t4, 8 /* Skipping first two entries. */
li t2, 2
1:
lw t1, 0(t4)
@@ -369,7 +370,8 @@ in_ram:
add t2, t6
sub t1, 4
-1: addi t1, 4
+1:
+ addi t1, 4
bltl t1, t2, 1b
sw zero, 0(t1) /* delay slot */
@@ -380,11 +382,10 @@ in_ram:
.end relocate_code
-
/* Exception handlers.
*/
romReserved:
- b romReserved
+ b romReserved
romExcHandle:
- b romExcHandle
+ b romExcHandle