[U-Boot] [PATCH v2 17/18] SPL: Enhance drivers/mtd/nand/nand_spl_load.c

[Scott Wood]

On 08/24/2012 04:20 PM, Tom Rini wrote:
> On Fri, Aug 24, 2012 at 04:09:13PM -0500, Scott Wood wrote:
>> On 08/20/2012 11:45 AM, Tom Rini wrote:
>>> diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile
>>> index 29dc20e..5475c8c 100644
>>> --- a/drivers/mtd/nand/Makefile
>>> +++ b/drivers/mtd/nand/Makefile
>>> @@ -27,12 +27,7 @@ LIB	:= $(obj)libnand.o
>>>  
>>>  ifdef CONFIG_CMD_NAND
>>>  ifdef CONFIG_SPL_BUILD
>>> -ifdef CONFIG_SPL_NAND_SIMPLE
>>> -COBJS-y += nand_spl_simple.o
>>> -endif
>>> -ifdef CONFIG_SPL_NAND_LOAD
>>> -COBJS-y	+= nand_spl_load.o
>>> -endif
>>> +COBJS-$(CONFIG_SPL_NAND_SIMPLE) += nand_spl_simple.o nand_spl_load.o
>>
>> OK, I was wrong, I will complain. :-)
>>
>> The commit message didn't mention you were changing
>> CONFIG_SPL_NAND_SIMPLE.  That needs to be able to support small SPLs.
>> Is your new "enhanced" nand_spl_load small enough (with proper
>> configuration) to work with all the SPLs that currently use
>> nand_spl/nand_boot.c (e.g. PPC 44x)?
> 
> OK, I suspect it would be close-to-fail.  There's a "few" bytes overhead
> to parse the header and so forth, but it also allows for direct Linux
> booting.  Is that something you want for these machines or no?

I don't think there's room for any new features at all.  The SPL must
fit in 4K.  Canyonlands is at 4020 bytes currently.

Why can't the new functionality be conditionally built?

> It wouldn't be hard to put the enhanced version nand_spl_simple.c and leave
> nand_spl_load.c alone.

nand_spl_simple.c is what I'm talking about needing to not expand.  Why
does the new stuff need to be bound to a specific NAND boot implementation?

-Scott