[PATCH 34/34] AMD IOMMU: add documentation for kernel parameters

[Ingo Molnar]

* FUJITA Tomonori <fujita.tomonori at lab.ntt.co.jp> wrote:

> On Thu, 26 Jun 2008 21:28:10 +0200
> Joerg Roedel <joerg.roedel at amd.com> wrote:
> 
> > Add documentation for the kernel parameters introduced with this driver.
> > 
> > Signed-off-by: Joerg Roedel <joerg.roedel at amd.com>
> > ---
> >  Documentation/kernel-parameters.txt |   12 ++++++++++++
> >  1 files changed, 12 insertions(+), 0 deletions(-)
> > 
> > diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
> > index e07c432..fc8f936 100644
> > --- a/Documentation/kernel-parameters.txt
> > +++ b/Documentation/kernel-parameters.txt
> > @@ -271,6 +271,18 @@ and is between 256 and 4096 characters. It is defined in the file
> >  	aic79xx=	[HW,SCSI]
> >  			See Documentation/scsi/aic79xx.txt.
> >  
> > +	amd_iommu=	[HW,X86-84]
> > +			Pass parameters to the AMD IOMMU driver in the system.
> > +			Possible values are:
> > +			off     - disable the driver for AMD IOMMU
> > +			isolate - enable device isolation (each device, as far
> > +			          as possible, will get its own protection
> > +			          domain)
> > +	amd_iommu_size= [HW,X86-64]
> > +			Define the size of the aperture for the AMD IOMMU
> > +			driver. Possible values are:
> > +			'32M', '64M' (default), '128M', '256M', '512M', '1G'
> > +
> >  	amijoy.map=	[HW,JOY] Amiga joystick support
> >  			Map of devices attached to JOY0DAT and JOY1DAT
> >  			Format: <a>,<b>
> 
> Documentation/x86_64/boot-options.txt would be a better place?
> 
> Probabaly, it would be better to clean up x86_64 IOMMU options.

yeah, agreed. There should be a single set of options that is largely 
transparent to the type of iommu used (for those options which are 
commonly implemented - like iommu_size= and iommu= both are).

That belongs in a followup patchset that is decoupled from this IOMMU 
driver submission and should include all current IOMMU(-ish) drivers. 
(If you'd like to work on that we could try any such patchset in -tip, 
ontop of tip/x86/amd-iommu - to keep integration simple.)

	Ingo