> -----Original Message----- > From: iommu-boun...@lists.linux-foundation.org [mailto:iommu- > boun...@lists.linux-foundation.org] On Behalf Of Joerg Roedel > Sent: Sunday, December 02, 2012 7:33 PM > To: Sethi Varun-B16395 > Cc: linux-kernel@vger.kernel.org; io...@lists.linux-foundation.org; Wood > Scott-B07421; linuxppc-...@lists.ozlabs.org; Tabi Timur-B04825 > Subject: Re: [PATCH 3/4 v5] iommu/fsl: Add iommu domain attributes > required by fsl PAMU driver. > > Hmm, we need to work out a good abstraction for this. > > On Tue, Nov 20, 2012 at 07:24:56PM +0530, Varun Sethi wrote: > > Added the following domain attributes required by FSL PAMU driver: > > 1. Subwindows field added to the iommu domain geometry attribute. > > Are the Subwindows mapped with full size or do you map only parts of the > subwindows? > [Sethi Varun-B16395] It's possible to map a part of the subwindow i.e. size of the mapping can be less than the sub window size.
> > + * This attribute indicates number of DMA subwindows supported by > > + * the geometry. If there is a single window that maps the entire > > + * geometry, attribute must be set to "1". A value of "0" implies > > + * that this mechanism is not used at all(normal paging is used). > > + * Value other than* "0" or "1" indicates the actual number of > > + * subwindows. > > + */ > > This semantic is ugly, how about a feature detection mechanism? > [Sethi Varun-B16395] A feature mechanism to query the type of IOMMU? -Varun -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
