Date: Thu, 7 Jun 2007 09:52:15 -0700 (PDT) From: Neil Bradley <nb@synthcom.com> Cc: arm@freebsd.org Subject: Re: 4-bit SD Card mode Message-ID: <20070607095022.U43808@synthcom.com> In-Reply-To: <54244.2001:6f8:101e:0:20e:cff:fe6d:6adb.1181211368.squirrel@webmail.alpha-tierchen.de> References: <50503.2001:6f8:101e:0:20e:cff:fe6d:6adb.1181202550.squirrel@webmail.alpha-tierchen.de> <20070607005128.T43808@synthcom.com> <53054.2001:6f8:101e:0:20e:cff:fe6d:6adb.1181203617.squirrel@webmail.alpha-tierchen.de> <20070607023728.X43808@synthcom.com> <54244.2001:6f8:101e:0:20e:cff:fe6d:6adb.1181211368.squirrel@webmail.alpha-tierchen.de>
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>> What is the CPU in question?
> There are issues with AT91RM9200, but now I think the problem is something
> else than I assumed.
One possibility - If DMA mode is being used, has there been a cache flush
on the region of memory where the SD card reads into? The ARM7/9 is *NOT*
cache coherent with DMA peripherals, which can give all kinds of bizarre
problems if the destination buffers are in the system's cache.
-->Neil
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C. Neil Bradley - KE7IXP - The one eyed man in the land of the blind is not
king. He's a prisoner.
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