From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Mosberger Date: Mon, 12 May 2003 18:40:18 +0000 Subject: Re: [Linux-ia64] new ia64 kernel patch (relative to 2.5.69) 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 Forgot to mention that I switched the ia64 tree from the PCI-DMA API to the generic DMA API. Doesn't affect device drivers, but all I/O MMU support needs to be updated accordingly. I already did swiotlb and the HP SBA I/O MMU support. I updated that machvec definitions for all platforms, but didn't try to update the SN-specific implementation (since I can't test it anyhow). Updating the SN-files should be straight-forward: you can look at swiotlb.c and hp/common/sba_iommu.c for what needs to be done. The one caveat is that sba_iommu.c for the moment continues to support only PCI-devices. This shouldn't be a problem for now, but it would be nice if someone could fix it so it can work with any device. While working on this, I started to wonder whether or not a DMA "sync" operation should imply a memory barrier. The API documentation is definitely ambiguous on this point and I didn't go out to look whether current practice is consistent (I suspect it isn't). Anyone want to argue for or against making "sync" a memory barrier? --david