X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=cpu%2Fmips%2Fstart.S;h=6e1a78ceac44175b1401a136ad0005e4494115b2;hb=ea638951acead7f1086c908c0b9f086beab82a22;hp=e91e2137d704f7eb8c0fe7ab6b1907673c1f2716;hpb=038ccac511214b062c56f22b9413f784b86bcd87;p=oweals%2Fu-boot.git

diff --git a/cpu/mips/start.S b/cpu/mips/start.S
index e91e2137d7..6e1a78ceac 100644
--- a/cpu/mips/start.S
+++ b/cpu/mips/start.S
@@ -22,12 +22,34 @@
  * MA 02111-1307 USA
  */
 
-
 #include <config.h>
 #include <version.h>
 #include <asm/regdef.h>
 #include <asm/mipsregs.h>
 
+	/*
+	 * 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
+
+	.macro	setup_c0_status_reset
+#ifdef CONFIG_64BIT
+	setup_c0_status ST0_KX 0
+#else
+	setup_c0_status 0 0
+#endif
+	.endm
 
 #define RVECENT(f,n) \
    b f; nop
@@ -192,7 +214,7 @@ _start:
 	.word	0x00000000
 	.word	0x03e00008
 	.word	0x00000000
-	.word   0x00000000
+	.word	0x00000000
 /* 0xbfc00428 */
 	.word	0xdc870000
 	.word	0xfca70000
@@ -203,7 +225,7 @@ _start:
 	.word	0x00000000
 	.word	0x03e00008
 	.word	0x00000000
-	.word   0x00000000
+	.word	0x00000000
 #endif /* CONFIG_PURPLE */
 	.align 4
 reset:
@@ -213,19 +235,11 @@ reset:
 	mtc0	zero, CP0_WATCHLO
 	mtc0	zero, CP0_WATCHHI
 
-	/* STATUS register */
-#ifdef  CONFIG_TB0229
-	li	k0, ST0_CU0
-#else
-	mfc0	k0, CP0_STATUS
-#endif
-	li	k1, ~ST0_IE
-	and	k0, k1
-	mtc0	k0, CP0_STATUS
-
-	/* CAUSE register */
+	/* WP(Watch Pending), SW0/1 should be cleared. */
 	mtc0	zero, CP0_CAUSE
 
+	setup_c0_status_reset
+
 	/* Init Timer */
 	mtc0	zero, CP0_COUNT
 	mtc0	zero, CP0_COMPARE
@@ -234,34 +248,24 @@ reset:
 	li	t0, CONF_CM_UNCACHED
 	mtc0	t0, CP0_CONFIG
 
-	/* Initialize GOT pointer.
-	*/
-	bal     1f
-	nop
-	.word   _GLOBAL_OFFSET_TABLE_
-	1:
-	move    gp, ra
-	lw      t1, 0(ra)
-	move	gp, t1
-
-#ifdef CONFIG_INCA_IP
-	/* Disable INCA-IP Watchdog.
+	/* Initialize $gp.
 	 */
-	la      t9, disable_incaip_wdt
-	jalr    t9
+	bal	1f
 	nop
-#endif
+	.word	_gp
+1:
+	lw	gp, 0(ra)
 
 	/* 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.
@@ -269,22 +273,22 @@ reset:
 	li	t0, CONF_CM_CACHABLE_NONCOHERENT
 	mtc0	t0, CP0_CONFIG
 
-
 	/* Set up temporary stack.
 	 */
+#ifdef CFG_INIT_RAM_LOCK_MIPS
 	li	a0, CFG_INIT_SP_OFFSET
-	la      t9, mips_cache_lock
-	jalr    t9
+	la	t9, mips_cache_lock
+	jalr	t9
 	nop
+#endif
 
 	li	t0, CFG_SDRAM_BASE + CFG_INIT_SP_OFFSET
 	la	sp, 0(t0)
 
 	la	t9, board_init_f
-	j	t9
+	jr	t9
 	nop
 
-
 /*
  * void relocate_code (addr_sp, gd, addr_moni)
  *
@@ -298,7 +302,7 @@ 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 +310,14 @@ 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 +333,7 @@ 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.
@@ -338,18 +342,25 @@ relocate_code:
 	/* Jump to where we've relocated ourselves.
 	 */
 	addi	t0, a2, in_ram - _start
-	j	t0
+	jr	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)
@@ -369,22 +380,22 @@ 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			*/
 
 	move	a0, a1
 	la	t9, board_init_r
-	j	t9
+	jr	t9
 	move	a1, a2		/* delay slot			*/
 
 	.end	relocate_code
 
-
 	/* Exception handlers.
 	 */
 romReserved:
-	b romReserved
+	b	romReserved
 
 romExcHandle:
-	b romExcHandle
+	b	romExcHandle