[U-Boot] [PATCH] arc: Introduce a possibility to not relocate U-boot
From: Alexey Brodkin Alexey.Brodkin@synopsys.com
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 abrodkin@synopsys.com Cc: Simon Glass sjg@chromium.org Cc: Bin Meng bmeng.cn@gmail.com Cc: Heiko Schocher hs@denx.de Cc: York Sun york.sun@nxp.com Cc: Stefan Roese sr@denx.de --- 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 7802f4054594..96b4bd3d8fa6 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 ac9944c4cf32..c78dd001d81d 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 7bfc73e8bca0..48c98d1a71af 100644 --- a/common/board_f.c +++ b/common/board_f.c @@ -904,7 +904,8 @@ 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
On 25 January 2018 at 11:22, Alexey Brodkin Alexey.Brodkin@synopsys.com wrote:
From: Alexey Brodkin Alexey.Brodkin@synopsys.com
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 abrodkin@synopsys.com Cc: Simon Glass sjg@chromium.org Cc: Bin Meng bmeng.cn@gmail.com Cc: Heiko Schocher hs@denx.de Cc: York Sun york.sun@nxp.com Cc: Stefan Roese sr@denx.de
arch/arc/lib/relocate.c | 6 ++++++ arch/arc/lib/start.S | 8 +++++++- common/board_f.c | 3 ++- 3 files changed, 15 insertions(+), 2 deletions(-)
Reviewed-by: Simon Glass sjg@chromium.org
Hi Simon, Tom,
On Sun, 2018-02-04 at 06:40 -0700, Simon Glass wrote:
On 25 January 2018 at 11:22, Alexey Brodkin Alexey.Brodkin@synopsys.com wrote:
From: Alexey Brodkin Alexey.Brodkin@synopsys.com
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 abrodkin@synopsys.com Cc: Simon Glass sjg@chromium.org Cc: Bin Meng bmeng.cn@gmail.com Cc: Heiko Schocher hs@denx.de Cc: York Sun york.sun@nxp.com Cc: Stefan Roese sr@denx.de
arch/arc/lib/relocate.c | 6 ++++++ arch/arc/lib/start.S | 8 +++++++- common/board_f.c | 3 ++- 3 files changed, 15 insertions(+), 2 deletions(-)
Reviewed-by: Simon Glass sjg@chromium.org
Is it OK if I pull this into my "next" tree?
I'm asking because common/board_f.c is affected even though that's just an addition of CONFIG_ARC in one #ifdef.
-Alexey
Hi Alexey,
On 20 February 2018 at 10:54, Alexey Brodkin Alexey.Brodkin@synopsys.com wrote:
Hi Simon, Tom,
On Sun, 2018-02-04 at 06:40 -0700, Simon Glass wrote:
On 25 January 2018 at 11:22, Alexey Brodkin Alexey.Brodkin@synopsys.com wrote:
From: Alexey Brodkin Alexey.Brodkin@synopsys.com
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 abrodkin@synopsys.com Cc: Simon Glass sjg@chromium.org Cc: Bin Meng bmeng.cn@gmail.com Cc: Heiko Schocher hs@denx.de Cc: York Sun york.sun@nxp.com Cc: Stefan Roese sr@denx.de
arch/arc/lib/relocate.c | 6 ++++++ arch/arc/lib/start.S | 8 +++++++- common/board_f.c | 3 ++- 3 files changed, 15 insertions(+), 2 deletions(-)
Reviewed-by: Simon Glass sjg@chromium.org
Is it OK if I pull this into my "next" tree?
I'm asking because common/board_f.c is affected even though that's just an addition of CONFIG_ARC in one #ifdef.
It is OK with me.
Regards, Simon
participants (2)
-
Alexey Brodkin -
Simon Glass