From mboxrd@z Thu Jan 1 00:00:00 1970 From: "David S. Miller" Date: Fri, 16 May 2003 00:06:03 +0000 Subject: [Linux-ia64] Re: 64 Bits DMA Addresses for Alloc Consistent Interfaces. 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 From: Colin Ngam Date: Thu, 15 May 2003 18:45:42 -0500 Something else I do not understand .. in the PCI world, what does Physical Memory Address got to do with 32Bit Mapped DMA Bus Address? Many platforms direct map, that is what I assumed was happening here and causing the problems. I have not seen any of the drivers broken yet - e.g. qlXXX, acenic, tg3 etc. It only works because these devices happen to allow >32-bit DMA addresses for descriptors. You will find eventually that many comodity pieces of PCI-X hardware will opt to only support 32-bit DMA addressing for descriptor tables and whatnot.