Date: Thu, 9 Jul 2009 17:23:12 +0200 From: Piotr =?iso-8859-2?q?Zi=EAcik?= <kosmo@semihalf.com> To: Sebastian Huber <sebastian.huber@embedded-brains.de> Cc: Rafal Jaworowski <raj@semihalf.com>, freebsd-arm@freebsd.org, freebsd-usb@freebsd.org, thompsa@freebsd.org Subject: Re: CPU Cache and busdma usage in USB Message-ID: <200907091723.13121.kosmo@semihalf.com> In-Reply-To: <4A547556.4050801@embedded-brains.de> References: <200906231035.43096.kosmo@semihalf.com> <200907081216.40100.kosmo@semihalf.com> <4A547556.4050801@embedded-brains.de>
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Wednesday 08 July 2009 12:30:46 Sebastian Huber napisa=B3(a): > Device to memory DMA transfer of a buffer: > (...) > 3. all accesses to the buffer via the cache must wait until the DMA has > finished And this is the problem in my oppinion - USB stack does not wait. =2D-=20 Best Regards. Piotr Zi=EAcik
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