| Message ID | 20110704174348.GC3016@harvey-pc.matrox.com |
|---|---|
| State | Changes Requested |
| Headers | show |
Dear Christopher Harvey, In message <20110704174348.GC3016@harvey-pc.matrox.com> you wrote: > Signed-off-by: Christopher Harvey <charvey@matrox.com> > --- > doc/README.arm-relocation | 9 ++++++++- > 1 files changed, 8 insertions(+), 1 deletions(-) Please let's stop with ARM specific documatation of things that are considered generic. > +The code that picks the location in RAM for ARM can be found in the > +arch/arm/lib/board.c file under the board_init_f function. under the function? Who dropped that code? :-) s/under/in/ Also delete "for ARM", and s/arm/<arch>/. This is not ARM specific. > +The postfix _f means executed from flash, and _r means from RAM. Maybe we whould rather write "... from NOR flash" to indicate that we actually mean ROM. > +The new location is picked with respect to the highest RAM address, and the > +exact final value depends heavily on compile time options. The source is the > +best documentation here. This should be changed, i. e. better documentation should be provided :-) Best regards, Wolfgang Denk
On Mon, Jul 04, 2011 at 09:43:24PM +0200, Wolfgang Denk wrote: > Dear Christopher Harvey, > > In message <20110704174348.GC3016@harvey-pc.matrox.com> you wrote: > > Signed-off-by: Christopher Harvey <charvey@matrox.com> > > --- > > doc/README.arm-relocation | 9 ++++++++- > > 1 files changed, 8 insertions(+), 1 deletions(-) > > Please let's stop with ARM specific documatation of things that are > considered generic. > > > +The code that picks the location in RAM for ARM can be found in the > > +arch/arm/lib/board.c file under the board_init_f function. > > under the function? Who dropped that code? :-) s/under/in/ > > Also delete "for ARM", and s/arm/<arch>/. This is not ARM specific. > I don't understand, I found the following snippet in arch/arm/lib/board.c --addr defined and set here-- gd->relocaddr = addr; gd->start_addr_sp = addr_sp; gd->reloc_off = addr - _TEXT_BASE; debug ("relocation Offset is: %08lx\n", gd->reloc_off); memcpy (id, (void *)gd, sizeof (gd_t)); relocate_code (addr_sp, id, addr); /* NOTREACHED - relocate_code() does not return */ Running grep -R gd->relocaddr *, I found similar assignments for various architectures. ... [snip] ... > > Best regards, > > Wolfgang Denk > Thanks for the clarification, -Chris
Dear Christopher Harvey, In message <20110706205857.GB2168@harvey-pc.matrox.com> you wrote: > > > Also delete "for ARM", and s/arm/<arch>/. This is not ARM specific. > > I don't understand, I found the following snippet in > arch/arm/lib/board.c > > --addr defined and set here-- > > gd->relocaddr = addr; > gd->start_addr_sp = addr_sp; > gd->reloc_off = addr - _TEXT_BASE; > debug ("relocation Offset is: %08lx\n", gd->reloc_off); > memcpy (id, (void *)gd, sizeof (gd_t)); > > relocate_code (addr_sp, id, addr); > /* NOTREACHED - relocate_code() does not return */ > > Running grep -R gd->relocaddr *, > I found similar assignments for various architectures. Yes, that's what I said: this is not ARM specific, it is supposed to be common code used by all architectures (except for the sad fact that there are several non-conforming implementations). But if we document it, we should document the nominal state. [If in doubt, use the powerpc implementation as reference.] Best regards, Wolfgang Denk
Hi Christopher,
Le 04/07/2011 19:43, Christopher Harvey a écrit :
> +The postfix _f means executed from flash, and _r means from RAM.
s/postfix/suffix/
Amicalement,
diff --git a/doc/README.arm-relocation b/doc/README.arm-relocation index 5a9a2fb..954627d 100644 --- a/doc/README.arm-relocation +++ b/doc/README.arm-relocation @@ -22,7 +22,7 @@ At cpu level: modify linker file and add a relocation and fixup loop At board level: dram_init(): bd pointer is now at this point not accessible, so only - detect the real dramsize, and store it in gd->ram_size. Bst detected + detect the real dramsize, and store it in gd->ram_size. Best detected with get_ram_size(). TODO: move also dram initialization there on boards where it is possible. @@ -38,6 +38,13 @@ At lib level: Boards which are not fixed to support relocation will be REMOVED! +The code that picks the location in RAM for ARM can be found in the +arch/arm/lib/board.c file under the board_init_f function. +The postfix _f means executed from flash, and _r means from RAM. +The new location is picked with respect to the highest RAM address, and the +exact final value depends heavily on compile time options. The source is the +best documentation here. + ----------------------------------------------------------------------------- For boards which boot from nand_spl, it is possible to save one copy
Signed-off-by: Christopher Harvey <charvey@matrox.com> --- doc/README.arm-relocation | 9 ++++++++- 1 files changed, 8 insertions(+), 1 deletions(-)