[U-Boot] [PATCH V3 2/3] arm/davinci: spl - boot device selection

[Mikhail Kshevetskiy]

On Wed, 11 Jul 2012 00:09:06 +0530
Sughosh Ganu <urwithsughosh at gmail.com> wrote:

> hi Mikhail,
> On Mon Jul 09, 2012 at 10:53:39PM +0400, Mikhail Kshevetskiy wrote:
> > This patch allow us to have a universal spl that detects a boot
> > device and select a corresponding boot algorithm for main u-boot part
> > (SOC_DA8XX only)
> 
> I have not tested this patch, will do so sometime this week. I had a
> couple of questions though.
> 
> <snip>
> 
> > diff --git a/arch/arm/cpu/arm926ejs/davinci/spl.c
> > b/arch/arm/cpu/arm926ejs/davinci/spl.c index 74632e5..50b4bbc 100644
> > --- a/arch/arm/cpu/arm926ejs/davinci/spl.c
> > +++ b/arch/arm/cpu/arm926ejs/davinci/spl.c
> 
> <snip>
> 
> >  void board_init_r(gd_t *id, ulong dummy)
> >  {
> > -#ifdef CONFIG_SPL_NAND_LOAD
> > -	nand_init();
> > -	puts("Nand boot...\n");
> > -	nand_boot();
> > -#endif
> > -#ifdef CONFIG_SPL_SPI_LOAD
> > -	mem_malloc_init(CONFIG_SYS_TEXT_BASE - CONFIG_SYS_MALLOC_LEN,
> > -			CONFIG_SYS_MALLOC_LEN);
> > +	u32 boot_device;
> > +	void (*uboot)(void) __noreturn;
> > +
> > +	mem_malloc_init(CONFIG_SYS_SPL_MALLOC_START,
> > +			CONFIG_SYS_SPL_MALLOC_SIZE);
> 
> We do not need any heap for the spl on the hawkboard, so can you
> please explain why do we need the heap allocation for all spl
> images. Can't this be made configurable.

this is needed at least for:
  * MMC support
  * SPI support
  * gunzip support (see next patch)

it can be configurable, but is it reasonable?

> >  
> >  	gd = &gdata;
> >  	gd->bd = &bdata;
> >  	gd->flags |= GD_FLG_RELOC;
> > +#ifdef CONFIG_SPL_SERIAL_SUPPORT
> >  	gd->baudrate = CONFIG_BAUDRATE;
> > -	serial_init();          /* serial communications setup */
> > +	serial_init();
> >  	gd->have_console = 1;
> > +#endif
> 
> This call to serial_init is not needed on the hawkboard -- we
> initialise the console needed for spl through NS16550_init for all
> da8xx based spl's in arch_cpu_init, which suffices for spl's debug
> message requirement. I know this is being used for spi based spl
> images, but now that this is being made common, just wanted to
> know why we need this. Also, do these changes have any impact on the
> size of the spl images.

hm, i'll look on it more carefully. I've just look on spi support in spl.

What about ymodem support? If I am not mistake it require a normal console.

> -sughosh