[U-Boot-Users] u-boot and 2.4.18 kernel problem

Sam Song samsongshu at yahoo.com.cn
Wed Jun 30 16:21:56 CEST 2004


Lokesh Kumar wrote:

> /* perform SDRAM initializsation sequence */
>
>	memctl->memc_mar = 0x00000088;
>	
>	memctl->memc_mcr = 0x80002105;
>	memctl->memc_mcr = 0x80002830;
>	memctl->memc_mcr = 0x80002106;

It seems sth out of place here.But I am not quite
sure.At least two cycles before refresh should be
safer than one.You could refer to my poor work
http://cvs.sourceforge.net/viewcvs.py/*checkout*/u-boot/u-boot/board/RPXlite_dw/RPXlite_dw.c?rev=1.1


>	udelay (1000);
>
>	size10 = dram_size (CFG_MAMR_10COL, (ulong > *)
SDRAM_BASE_PRELIM,
					
>	SDRAM_MAX_SIZE);
>
>	memctl->memc_mamr |= MAMR_PTAE;
>	return (size10);
> }

> I do not have the upm config tool from motorola to 
> verify these settings.
> Has anybody used this chip with mpc855T and can help
> me figure this out?

I tested 2 MT48LC16M16A2-75 in 32-bit mode on 832e
RPXlite_DW board.It worked fine.Next,I will also test
2 MT48LC8M16A2 on a 8xx custom board.So please let me
know your advancement.I just had a look at the
datasheet of MT48LC8M16A2 and MT48LC16M16A2.They have
exactly the same timing waveform on initialization.

Hope this help!

Best regards,

Sam

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