arm: move C runtime setup code in crt0.S

Move all the C runtime setup code from every start.S
in arch/arm into arch/arm/lib/crt0.S. This covers
the code sequence from setting up the initial stack
to calling into board_init_r().

Also, rewrite the C runtime setup and make functions
board_init_*() and relocate_code() behave according to
normal C semantics (no jumping across the C stack any
more, etc).

Some SPL targets had to be touched because they use
start.S explicitly or for some reason; the relevant
maintainers and custodians are cc:ed.

Signed-off-by: Albert ARIBAUD <albert.u.boot@aribaud.net>

1 files changed, 8 insertions, 45 deletions

diff --git a/arch/arm/cpu/arm720t/start.S b/arch/arm/cpu/arm720t/start.S
index c2a7763..771d386 100644
--- a/arch/arm/cpu/arm720t/start.S
+++ b/arch/arm/cpu/arm720t/start.S
@@ -147,12 +147,7 @@ reset:
 	bl	cpu_init_crit
 #endif
 
-/* Set stackpointer in internal RAM to call board_init_f */
-call_board_init_f:
-	ldr	sp, =(CONFIG_SYS_INIT_SP_ADDR)
-	bic	sp, sp, #7 /* 8-byte alignment for ABI compliance */
-	ldr	r0,=0x00000000
-	bl	board_init_f
+	bl	_main
 
 /*------------------------------------------------------------------------------*/
 
@@ -169,14 +164,10 @@ relocate_code:
 	mov	r5, r1	/* save addr of gd */
 	mov	r6, r2	/* save addr of destination */
 
-	/* Set up the stack						    */
-stack_setup:
-	mov	sp, r4
-
 	adr	r0, _start
 	cmp	r0, r6
 	moveq	r9, #0		/* no relocation. relocation offset(r9) = 0 */
-	beq	clear_bss		/* skip relocation */
+	beq	relocate_done		/* skip relocation */
 	mov	r1, r6			/* r1 <- scratch for copy_loop */
 	ldr	r3, _bss_start_ofs
 	add	r2, r0, r3		/* r2 <- source end address	    */
@@ -228,43 +219,10 @@ fixnext:
 	blo	fixloop
 #endif
 
-clear_bss:
-#ifndef CONFIG_SPL_BUILD
-	ldr	r0, _bss_start_ofs
-	ldr	r1, _bss_end_ofs
-	mov	r4, r6			/* reloc addr */
-	add	r0, r0, r4
-	add	r1, r1, r4
-	mov	r2, #0x00000000		/* clear			    */
-
-clbss_l:cmp	r0, r1			/* clear loop... */
-	bhs	clbss_e			/* if reached end of bss, exit */
-	str	r2, [r0]
-	add	r0, r0, #4
-	b	clbss_l
-clbss_e:
-
-	bl coloured_LED_init
-	bl red_led_on
-#endif
+relocate_done:
 
-/*
- * We are done. Do not return, instead branch to second part of board
- * initialization, now running from RAM.
- */
-	ldr	r0, _board_init_r_ofs
-	adr	r1, _start
-	add	lr, r0, r1
-	add	lr, lr, r9
-	/* setup parameters for board_init_r */
-	mov	r0, r5		/* gd_t */
-	mov	r1, r6		/* dest_addr */
-	/* jump to it ... */
 	mov	pc, lr
 
-_board_init_r_ofs:
-	.word board_init_r - _start
-
 _rel_dyn_start_ofs:
 	.word __rel_dyn_start - _start
 _rel_dyn_end_ofs:
@@ -272,6 +230,11 @@ _rel_dyn_end_ofs:
 _dynsym_start_ofs:
 	.word __dynsym_start - _start
 
+	.globl	c_runtime_cpu_setup
+c_runtime_cpu_setup:
+
+	mov	pc, lr
+
 /*
  *************************************************************************
  *