[U-Boot] [RESEND][PATCH 21/24] sh4: fix start.S by calling board_init_f() after first code relocation

Vladimir Zapolskiy
2016-11-27T22:15:33Z

Like on ARM platform keep the first code relocation from a U-boot
image storage to RAM at CONFIG_SYS_TEXT_BASE, then pass execution to a
generic board_init_f() with empty GD flags. If CONFIG_SYS_TEXT_BASE is
equal to a calculated by board_init_f() relocation address there will
be no more code and data copy, however it's worth to mention that the
first copy happens even if $pc on _start is the same as
CONFIG_SYS_TEXT_BASE, on practice this works without a problem.

Also note that _sh_start is renamed back to _start to correct
gd->mon_len calculation by setup_mon_len(), the opposite rename was
done in pre-generic board commit 2024b968ee9 ("sh: Fix build in start.S").

Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
---
arch/sh/cpu/sh4/start.S | 23 +++++++++++------------
1 file changed, 11 insertions(+), 12 deletions(-)

diff --git a/arch/sh/cpu/sh4/start.S b/arch/sh/cpu/sh4/start.S
index 77fc221..416adcf 100644
--- a/arch/sh/cpu/sh4/start.S
+++ b/arch/sh/cpu/sh4/start.S
@@ -1,6 +1,6 @@
/*
- * (C) Copyright 2007, 2010
- * Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
+ * Copyright (C) 2016 Vladimir Zapolskiy <vz@mleia.com>
+ * Copyright (C) 2007, 2010 Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
*
* SPDX-License-Identifier: GPL-2.0+
*/
@@ -12,7 +12,7 @@
.align 2

.global _start
-_sh_start:
+_start:
mov.l ._lowlevel_init, r0
100: bsrf r0
nop
@@ -21,7 +21,7 @@ _sh_start:
nop
1: sts pr, r5
mov.l ._reloc_dst, r4
- add #(_sh_start-1b), r5
+ add #(_start-1b), r5
mov.l ._reloc_dst_end, r6

2: mov.l @r5+, r1
@@ -42,10 +42,9 @@ _sh_start:
mov.l ._gd_init, r13 /* global data */
mov.l ._stack_init, r15 /* stack */

- #TODO(sh maintainer): Fix this up to call the correct code
- #mov.l ._sh_generic_init, r0
- #jsr @r0
- nop
+ mov.l ._sh_generic_init, r0
+ jsr @r0
+ mov #0, r4

loop:
bra loop
@@ -53,10 +52,10 @@ loop:
.align 2

._lowlevel_init: .long (lowlevel_init - (100b + 4))
-._reloc_dst: .long reloc_dst
+._reloc_dst: .long _start
._reloc_dst_end: .long reloc_dst_end
._bss_start: .long bss_start
._bss_end: .long bss_end
-._gd_init: .long (_sh_start - GENERATED_GBL_DATA_SIZE)
-._stack_init: .long (_sh_start - GENERATED_GBL_DATA_SIZE - CONFIG_SYS_MALLOC_LEN - 16)
-#._sh_generic_init: .long sh_generic_init
+._gd_init: .long (_start - GENERATED_GBL_DATA_SIZE)
+._stack_init: .long (_start - GENERATED_GBL_DATA_SIZE - CONFIG_SYS_MALLOC_LEN - 16)
+._sh_generic_init: .long board_init_f
--
2.10.2