From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Mosberger Date: Tue, 04 Dec 2001 19:56:21 +0000 Subject: Re: [Linux-ia64] 2.4.16-ia64-011128 is missing dma64_addr_t 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 Tue, 4 Dec 2001 17:29:32 +0100, Christoph Hellwig said: Christoph> The problem is that we need a uniform API on all Linux Christoph> plattforms. Linus has decided on this one, may it be Christoph> nice or not. (And I don't really like the pci_dac_* part Christoph> as it is to implementation-specific). >> The only extra overhead of going through normal pci mapping >> routines is a function call. If that's noticable, you have a >> very fast device indeed. Christoph> On IA64 yes, on i386 or other 32bit plattforms not. Then fix those implementations. There is nothing difficult in first checking the DMA mask. Look, this is precisely why I'm reluctant to add the pci_dac*() support now: people will use it in the wrong way and eventually we'll have to add yet another layer of mapping underneath pci_dac_*(). pci_dac_*() is not intended for all DAC-capable devices. It is intended for DAC capable devices that generate tons of mappings. If you don't believe me, check with Dave Miller. --david