From mboxrd@z Thu Jan 1 00:00:00 1970 From: Grant Grundler Date: Sun, 18 May 2003 17:22:03 +0000 Subject: Re: [Linux-ia64] Re: [patch] support 64 bit pci_alloc_consistent Message-Id: List-Id: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org On Sun, May 18, 2003 at 09:43:41AM +0000, Arjan van de Ven wrote: > Most drivers will just say "look I > can do THIS much. I don't give a flying fish about how much of > that you actually use". At least in the probing code. The platform code needs a way to indicate the given mask will not work. Rejecting proposals by the driver seems reasonable if the driver only supports two different masks anyway (eg 64 and 32-bit). In the case of a platform requiring 64-bit masks for consistent mappings, the platform DMA code must reject proposals for non-64-bit DMA masks. (eg PCI-X device implementing less than 64-bits) In both cases the driver will care because it will crash the box otherwise. grant