lkml.org 
[lkml]   [2011]   [Jun]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [RFC 0/6] iommu: generic api migration and grouping
Hi,

On Thu, Jun 02, 2011 at 06:27:37PM -0400, Ohad Ben-Cohen wrote:
> First stab at iommu consolidation:
>
> - Migrate OMAP's iommu driver to the generic iommu API. With this in hand,
> users can now start using the generic iommu layer instead of calling
> omap-specific iommu API.
>
> New code that requires functionality missing from the generic iommu api,
> will add that functionality in the generic framework (e.g. adding framework
> awareness to multi page sizes, supported by the underlying hardware, will
> avoid the otherwise-inevitable code duplication when mapping a memory
> region).

The IOMMU-API already supports multiple page-sizes. See the
'order'-parameter of the map/unmap functions.

> Further generalizing of iovmm strongly depends on our broader plans for
> providing a generic virtual memory manager and allocation framework
> (which, as discussed, should be separated from a specific mapper).

The generic vmm for DMA is called DMA-API :) Any reason for not using
that (those reasons should be fixed)?

> iovmm has a mainline user: omap3isp, and therefore must be maintained,
> but new potential users will either have to generalize it, or come up
> with a different generic framework that will replace it.

Moving to the DMA-API should be considered here. If it is too much work
iovmm can stay for a while, but the goal should be to get rid of it and
only use the DMA-API.

> - Create a dedicated iommu drivers folder (and put the base iommu code there)

Very good idea.


Joerg

P.S.: Please also Cc the iommu-list (iommu@lists.linux-foundation.org)
in the future for IOMMU related patches.

--
AMD Operating System Research Center

Advanced Micro Devices GmbH Einsteinring 24 85609 Dornach
General Managers: Alberto Bozzo, Andrew Bowd
Registration: Dornach, Landkr. Muenchen; Registerger. Muenchen, HRB Nr. 43632



\
 
 \ /
  Last update: 2011-06-06 12:11    [from the cache]
©2003-2014 Jasper Spaans. Advertise on this site