[U-Boot] [PATCH 4/6] nand_spl: update udelay for Freescale boards

[Scott Wood <scottwood@freescale.com>]

On 08/13/2012 01:10 PM, Matthew McClintock wrote:
> Let's use the more appropriate udelay for the nand_spl. While we
> can't make use of u-boot's full udelay we can atl east use a for
> loop that won't get optimized away .Since we have the bus clock
> we can use the timebase to calculate wall time.
> 
> Looked at reusing the u-boot udelay functions but it pulls in a lot
> of code as well as depends on the gd struct and would require a lot
> of rework

What's wrong with depending on the gd struct?

> +extern u32 bus_clk;

Change to gd->bus_clk as mentioned in patch 5/6.

> +void udelay(unsigned long usec) {
> +	u32 ticks_per_usec = bus_clk / (8 * 1000000);
> +	u32 ticks = ticks_per_usec * usec;
> +	u32 s = mfspr(SPRN_TBRL);
> +
> +	while ((mfspr(SPRN_TBRL)-s) < ticks);
> +}

Opening brace goes on its own line for function definitions.  Use spaces
around that '-'.

Dividing the bus clock by 8 only works for e500v1/v2, but this isn't
labelled as specific to those cores.

> diff --git a/nand_spl/board/freescale/p1010rdb/Makefile b/nand_spl/board/freescale/p1010rdb/Makefile
> index 8d240ea..cdbd492 100644
> --- a/nand_spl/board/freescale/p1010rdb/Makefile
> +++ b/nand_spl/board/freescale/p1010rdb/Makefile
> @@ -39,7 +39,8 @@ CFLAGS	+= -DCONFIG_NAND_SPL
>  
>  SOBJS	= start.o resetvec.o ticks.o
>  COBJS	= cache.o cpu_init_early.o cpu_init_nand.o fsl_law.o law.o \
> -	  nand_boot.o nand_boot_fsl_ifc.o ns16550.o tlb.o tlb_table.o
> +	  nand_boot.o nand_boot_fsl_ifc.o ns16550.o tlb.o tlb_table.o \
> +	  ../common.o
>  
>  SRCS	:= $(addprefix $(obj),$(SOBJS:.o=.S) $(COBJS:.o=.c))
>  OBJS	:= $(addprefix $(obj),$(SOBJS) $(COBJS))
> @@ -123,6 +124,9 @@ ifneq ($(OBJTREE), $(SRCTREE))
>  $(obj)nand_boot.c:
>  	@rm -f $(obj)nand_boot.c
>  	ln -s $(SRCTREE)/nand_spl/board/$(BOARDDIR)/nand_boot.c $(obj)nand_boot.c
> +$(obj)../common.c:
> +	@rm -f $(obj)../common.c
> +	ln -s $(SRCTREE)/nand_spl/board/freescale/common.c $(obj)../common.c
>  endif

Why are you creating a link in the parent directory?

-Scott