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Subject: Re: ECC support
To: Dieter BSD <dieterbsd@gmail.com>, freebsd-hardware@FreeBSD.org,
 freebsd-hackers@FreeBSD.org
References: <CAA3ZYrBXZn1WpHWYGJYWJDPsk7iDahCas8RhnHC4w+abf4w4hA@mail.gmail.com>
From: Andriy Gapon <avg@FreeBSD.org>
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On 15/09/2015 23:53, Dieter BSD wrote:
> Assuming that a board does have the necessary connections but
> the firmware does not have ECC support, is there some reason that
> ECC support could not be added to the OS instead of the firmware?

Yes, there is.  The memory controller is programmed by the code that runs from
ROM and uses no RAM (or the CPU cache is used as the RAM).  Once the real RAM
gets used it's too late to reprogram the DRAM controller.  This is true at least
for most or all of the modern day x86 hardware.

-- 
Andriy Gapon