[U-Boot] [PATCH 6/8] ARM: bootm: allow skipping fdt memory node fixup

[Simon Glass]

Hi Andre,

On 5 June 2015 at 18:14, Andre Przywara <osp at andrep.de> wrote:
> On Fri, 5 Jun 2015 08:12:25 -0600
> Simon Glass <sjg at chromium.org> wrote:
>
> Hi Simon,
>
> thanks for taking a look.
>
>> On 4 June 2015 at 17:58, Andre Przywara <osp at andrep.de> wrote:
>> > From: Rob Herring <robh at kernel.org>
>> >
>> > Currently, u-boot will always fixup the DT memory node on ARM. If
>> > the dtb has correct memory information, then we don't want or need
>> > u-boot to touch the memory node. Allow platforms to skip this by
>> > not filling in dram bank information.
>> >
>> > Signed-off-by: Rob Herring <robh at kernel.org>
>> > Signed-off-by: Andre Przywara <osp at andrep.de>
>> > ---
>> >  arch/arm/lib/board.c     | 2 ++
>> >  arch/arm/lib/bootm-fdt.c | 5 ++++-
>> >  2 files changed, 6 insertions(+), 1 deletion(-)
>> >
>> > diff --git a/arch/arm/lib/board.c b/arch/arm/lib/board.c
>> > index 37ea6e9..a3c7315 100644
>> > --- a/arch/arm/lib/board.c
>> > +++ b/arch/arm/lib/board.c
>>
>> I don't think we should be patching this file now - everything should
>> be on generic board.
>
> Right, looking closer at this patch much of it is actually not
> necessary. Having CONFIG_NR_DRAM_BANKS set to 0 automatically skips a
> lot of the code already, so we don't need any extra gating.
> Hope that there are no compilers which complain about zero-sized arrays.
> The only thing that harms us is the final fdt_setprop(), which will
> _clear_ the reg property in the memory node in this case.
> So I replaced this patch by just skipping the reg property setting if
> the number of banks is 0 in common/fdt_support.c.
> From looking at all callers of fdt_fixup_memory_banks() this looks like
> a safe approach. Any objections?
> I will send the replaced patch with the next revision.

Should be OK - can you please add docs for that function to the header
file? See fdt_fixup_display() for an example.

>
> Cheers,
> Andre.
>
>>
>> > @@ -191,8 +191,10 @@ typedef int (init_fnc_t) (void);
>> >
>> >  __weak void dram_init_banksize(void)
>> >  {
>> > +#if
>> >         gd->bd->bi_dram[0].start = CONFIG_SYS_SDRAM_BASE;
>> >         gd->bd->bi_dram[0].size =  gd->ram_size;
>> > +#endif
>> >  }
>> >
>> >  __weak int arch_cpu_init(void)

Regards,
Simon