From 264d298fda39c5caa9505702b257a1f60c3b7352 Mon Sep 17 00:00:00 2001 From: Alexey Brodkin Date: Wed, 16 Dec 2015 19:24:10 +0300 Subject: [PATCH] arc: Introduce a possibility to not relocate U-boot Disabling relocation might be useful on ARC for 2 reasons: a) For advanced debugging with Synopsys proprietary MetaWare debugger which is capable of accessing much more specific hardware resources compared to gdb. For example it may show contents of L1 and L2 caches, internal states of some hardware blocks etc. But on the downside MetaWare debugger still cannot work with PIE. Even though that limitation could be work-arounded with change of ELF's header and stripping down all debug info but with it we won't have debug info for source-level debugging which is quite inconvenient. b) Some platforms which might benefit from usage of U-Boot basically don't have enough RAM to accommodate relocation of U-Boot so we keep code in flash and use as much of RAM as possible for more interesting things. Signed-off-by: Alexey Brodkin Cc: Simon Glass Cc: Bin Meng Cc: Heiko Schocher Cc: York Sun Cc: Stefan Roese --- arch/arc/lib/relocate.c | 6 ++++++ arch/arc/lib/start.S | 8 +++++++- common/board_f.c | 3 ++- 3 files changed, 15 insertions(+), 2 deletions(-) diff --git a/arch/arc/lib/relocate.c b/arch/arc/lib/relocate.c index 7802f40..96b4bd3 100644 --- a/arch/arc/lib/relocate.c +++ b/arch/arc/lib/relocate.c @@ -17,6 +17,9 @@ int copy_uboot_to_ram(void) { size_t len = (size_t)&__image_copy_end - (size_t)&__image_copy_start; + if (gd->flags & GD_FLG_SKIP_RELOC) + return 0; + memcpy((void *)gd->relocaddr, (void *)&__image_copy_start, len); return 0; @@ -40,6 +43,9 @@ int do_elf_reloc_fixups(void) Elf32_Rela *re_src = (Elf32_Rela *)(&__rel_dyn_start); Elf32_Rela *re_end = (Elf32_Rela *)(&__rel_dyn_end); + if (gd->flags & GD_FLG_SKIP_RELOC) + return 0; + debug("Section .rela.dyn is located at %08x-%08x\n", (unsigned int)re_src, (unsigned int)re_end); diff --git a/arch/arc/lib/start.S b/arch/arc/lib/start.S index ac9944c..c78dd00 100644 --- a/arch/arc/lib/start.S +++ b/arch/arc/lib/start.S @@ -78,7 +78,13 @@ ENTRY(_start) /* Zero the one and only argument of "board_init_f" */ mov_s %r0, 0 - j board_init_f + bl board_init_f + + /* We only get here if relocation is disabled by GD_FLG_SKIP_RELOC */ + /* Make sure we don't lose GD overwritten by zero new GD */ + mov %r0, %r25 + mov %r1, 0 + bl board_init_r ENDPROC(_start) /* diff --git a/common/board_f.c b/common/board_f.c index 62588c5..ae8bdb7 100644 --- a/common/board_f.c +++ b/common/board_f.c @@ -900,7 +900,8 @@ void board_init_f(ulong boot_flags) hang(); #if !defined(CONFIG_ARM) && !defined(CONFIG_SANDBOX) && \ - !defined(CONFIG_EFI_APP) && !CONFIG_IS_ENABLED(X86_64) + !defined(CONFIG_EFI_APP) && !CONFIG_IS_ENABLED(X86_64) && \ + !defined(CONFIG_ARC) /* NOTREACHED - jump_to_copy() does not return */ hang(); #endif