[U-Boot] [PATCH v4 07/13] davinci: Use correct #ifdef around gdata/bdata

[Simon Glass]

Hi,

On Sat, Mar 3, 2012 at 12:22 PM, Simon Glass <sjg at chromium.org> wrote:
> Hi,
>
> On Mon, Feb 27, 2012 at 4:02 AM, Sughosh Ganu <urwithsughosh at gmail.com> wrote:
>> hi Christian,
>>
>> On Mon Feb 27, 2012 at 12:37:16PM +0100, Christian Riesch wrote:
>>> Hi Sughosh,
>>>
>>> On Mon, Feb 27, 2012 at 11:56 AM, Sughosh Ganu <urwithsughosh at gmail.com> wrote:
>>> > hi Christian,
>>> >
>>> > On Mon Feb 27, 2012 at 11:39:42AM +0100, Christian Riesch wrote:
>>> >> Hi,
>>> >>
>>> >> On Mon, Feb 27, 2012 at 11:16 AM, Sughosh Ganu <urwithsughosh at gmail.com> wrote:
>>> >
>>> > <snip>
>>> >
>>> >> >> >>  arch/arm/cpu/arm926ejs/davinci/spl.c |    2 ++
>>> >> >> >>  1 files changed, 2 insertions(+), 0 deletions(-)
>>> >> >> >>
>>> >> >> >> diff --git a/arch/arm/cpu/arm926ejs/davinci/spl.c b/arch/arm/cpu/arm926ejs/davinci/spl.c
>>> >> >> >> index b1eff26..2861907 100644
>>> >> >> >> --- a/arch/arm/cpu/arm926ejs/davinci/spl.c
>>> >> >> >> +++ b/arch/arm/cpu/arm926ejs/davinci/spl.c
>>> >> >> >> @@ -32,10 +32,12 @@
>>> >> >> >>
>>> >> >> >>  #ifdef CONFIG_SPL_LIBCOMMON_SUPPORT
>>> >> >> >>
>>> >> >> >> +#ifdef CONFIG_SPL_SPI_LOAD
>>> >> >> >>  DECLARE_GLOBAL_DATA_PTR;
>>> >> >> >>  /* Define global data structure pointer to it*/
>>> >> >> >>  static gd_t gdata __attribute__ ((section(".data")));
>>> >> >> >>  static bd_t bdata __attribute__ ((section(".data")));
>>> >> >> >> +#endif
>>> >
>>> > <snip>
>>> >
>>> >> >> >  Can you specify which boards you get this warning for. With your
>>> >> >> >  patch to add libcommon to hawkboard's spl image, this is now also
>>> >> >> >  needed for hawkboard which uses CONFIG_SPL_NAND_LOAD.
>>> >>
>>> >> Simon's patch is for the hawkboard, since due to another patch in his
>>> >> patchset LIBCOMMON is enabled in hawkboard's SPL. Now we have a board
>>> >> that boots from NAND with SPL and has LIBCOMMON enabled (Simon, I did
>>> >> not check the rest of your patchset, why do you need LIBCOMMON on the
>>> >> hawkboard at all?)
>>> >
>>> >  LIBCOMMON is now needed as the generic relocation based functions
>>> >  are part of the libcommon.o, which are being enabled in the same
>>> >  patchset for all arm boards. So if i understand correct, all arm
>>> >  board based spl's now need libcommon and libgeneric.
>>> >
>>> >  The only thing i see is that libcommon and libgeneric are not
>>> >  defined for cam_enc_4xx board which uses spl, and this patchset does
>>> >  not add it either. Not sure whether it got missed.
>>>
>>> When I asked Heiko Schocher a few month ago why he defined putc and
>>> puts in arch/arm/cpu/arm926ejs/davinci/spl.c he replied that he could
>>> not use LIBCOMMON due to size limitations for the SPL. So I guess that
>>> this board will not be able to use the generic relocation functions,
>>> unless the SPL is smaller than 16kB, right? Simon's patchset will
>>> break this board then, right?
>
> If it pushes it over 16KB, although it's not clear that it will. So
> far I haven't seen this and I would hope that builds would fail in
> this case (normally I got a 'cannot move program counter backwards'
> error).
>
> But clearly putting this code in spl.c is a bit ugly because it
> hard-codes the driver and duplicates code in common/console.c:
>
> void putc(char c)
> {
>        if (c == '\n')
>                NS16550_putc((NS16550_t)(CONFIG_SYS_NS16550_COM1), '\r');
>
>        NS16550_putc((NS16550_t)(CONFIG_SYS_NS16550_COM1), c);
> }
>
> Can someone please check what is the maximum SPL size on one of these
> boards? Generic relocation increases the spl from 5.9KB to 10KB. Is
> there an 8KB limit?
>
> One option if this really is a problem is to move common/reloc.c to
> lib/reloc.c, although there isn't really a huge amount of
> justification for that given that it is U-Boot code. Perhaps we could
> claim that it is a relocation library and not U-Boot-specific?
>
>>
>>  That is exactly what i reported in one of the threads in response to
>>  addition of libcommon and libgeneric to the hawkboard's spl. In
>>  fact, this might cause problems on quite a few boards with spl size
>>  restrictions. I am not sure, whether the generic relocation feature
>>  should be turned on by default on all boards or should be a config
>>  option -- at least for the spl builds. Another option would be to
>>  move it to a place where it is not needed to compile in the entire
>>  libcommon/libgeneric support that is not needed for the generic
>>  relocation code. I think that would help us keep the generic
>>  relocation without the size bloat that we see right now.
>>
>>  http://lists.denx.de/pipermail/u-boot/2012-February/118567.html
>
> Well it would be nice to find out what the limit is. I might be able
> to squeeze it a bit more even in common. But failing that the putc()
> hack and lib/ might be the most expedient solution at this stage.
>
>>
>> <snip>
>>
>>> >> void board_init_r(gd_t *id, ulong dummy)
>>> >> {
>>> >> #ifdef CONFIG_SPL_LIBCOMMON_SUPPORT
>>> >>         mem_malloc_init(CONFIG_SYS_TEXT_BASE - CONFIG_SYS_MALLOC_LEN,
>>> >>                         CONFIG_SYS_MALLOC_LEN);
>>> >
>>> >  Can you please explain why we need the mem_malloc_init. I did not
>>> >  include this, and spl boots up just fine on my board.
>>> >
>>>
>>> malloc is required for the SPI code only, so you could also put it
>>> within #ifdef CONFIG_SPL_SPI_LOAD
>>
>>  Ok, i will move the common changes to a static function, and call
>>  it from both the nand and spi load cases. Or, should i wait till a
>>  consensus is drawn on whether to enable this feature for spl images
>>  also. In case this is not needed for spl, then we don't need this
>>  change.
>
> My series removes the old relocation code, so it really does need to
> work for SPL also. I have put a bit of effort in here to tidy this up
> and I don't think it is hard to resolve this last problem.
>
> I will investigate this a bit more and then suggest a solution.

Actually further to this it seems that it is just that raise() is
calling printf(). Seems like we can punt this unless anyone has
objections. Alternatively we could use puts() and just print a general
message. I will send a patch.

Regards,
Simon

>
> Regards,
> Simon
>
>>
>> -sughosh