[U-Boot] [PATCH] [RFC] memsize.c: adapt get_ram_size() for address spaces >32 bit

[Wolfgang Denk <wd@denx.de>]

Dear Timur Tabi,

In message <4BFECF82.60901@freescale.com> you wrote:
> 
> Scott pointed out that writing/reading memory to determine how much memory
> actually exists is dangerous.  I'm not convinced that I should be using
> get_ram_size().  I still believe that I shouldn't.

And I point out that we have been doing this for a decade on tens of
different board configurations with millions of devices in the field.

> I have not been able to find any other PowerPC system in U-boot that
> supports more memory than is mapped.  If you know of one, please tell me.

The systems I know are the opposite - initially they map more memory
than they support, then they determine the real size, then they
adjust the mapping to the real size.

> My point is that sizeof(phys_addr_t) has got nothing to do with the size of
> the read/write operation, so I think it's wrong on all platforms.

Actually it will only be wrong on systems where phys_addr_t != ulong,
but you are right.

Best regards,

Wolfgang Denk

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