From mboxrd@z Thu Jan  1 00:00:00 1970
From: Timur Tabi <timur@freescale.com>
Date: Thu, 27 May 2010 15:03:43 -0500
Subject: [U-Boot] [PATCH] powerpc: add support for the Freescale P1022DS
 reference board
In-Reply-To: <20100527195318.71B5EEAC238@gemini.denx.de>
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Wolfgang Denk wrote:

>> It also doesn't handle non-power-of-two sized memory -- don't rely on the
>> value it returns.
> 
> Such configurations are usually set up of from several differently
> sized banks of memory, and get_ram_size() is always run per bank. So
> as long as chip manufacturers continue to make RAM chips with
> power-of-two sizes only, everything should be fine.

What if the board has two DIMM slots, one of which has a 1GB DIMM and the
other has a 512MB DIMM?

>> [1] It's worse than machine checks, what if some I/O device is mapped
>> directly after RAM?  IIRC people have run into this sort of problem doing
>> this type of memory sizing on PCs.
> 
> Well, let's call this a bug in setting up the memory map for the
> system ;-)

I thought get_ram_size() was supposed to safely determine how much RAM is
actually in the system?  Otherwise, it should be called verify_ram_size().

-- 
Timur Tabi
Linux kernel developer at Freescale