[RFC/RFT PATCH 0/5] mm: ARM nobootmem and few dma_mask fixes

Russell King - ARM Linux linux at arm.linux.org.uk
Mon Jul 29 07:15:03 EDT 2013

On Fri, Jul 26, 2013 at 12:28:26PM -0400, Santosh Shilimkar wrote:
> On Friday 26 July 2013 11:10 AM, Russell King - ARM Linux wrote:
> > On Fri, Jul 12, 2013 at 05:48:09PM -0400, Santosh Shilimkar wrote:
> >> The series is an attempt to move ARM port to NO_BOOTMEM. As discussed
> >> on list NO_BOOTMEM move needed updates to max*pfn meaning to be maximum
> >> PFNs but that breaks the dma_mask for few block layer drivers since
> >> ARM start of physical memory is not PFN0 unlike most of the architectures.
> >> Some more read on it is here:
> >> 	http://lwn.net/Articles/543408/
> >> 	http://lwn.net/Articles/543424/
> >>
> >> To address this issue, we introduce generic dma_max_pfn() helper which
> >> can be overridden from the architectures.
> >> 	
> >> Another intention behind move to nobootmem is also to convert ARM to
> >> switch to memblock and getting rid of bootmem allocator dependency which
> >> don't work for LPAE machines which has physical memory starting beyond
> >> 4 GB boundary. It needs changes to core kernel and also a new memblock
> >> API. More on this can be found here:
> >> 	https://lkml.org/lkml/2013/6/29/77
> >>
> >> I have been trying to cook up these patches with kind help from Russell
> >> and we know series don't solve all the dma_mask bad assumptions. But at
> >> least I am hoping that it can get the ball rolling.	
> >>
> >> Comments/testing help is welcome !!
> > 
> > As this is related to some of the cleanup of dma_mask which I've been
> > doing, I think it may make sense to roll this into one tree.  Any
> > objection to that?
> > 
> > Can we get any acks on this stuff from Jens and Jejb etc - especially
> > for the bits which touch block/ and for the scsi bits as these are
> > touching other subsystems.  (oddly, linux-scsi wasn't on the original
> > mail for this series summary.)
> > 
> Sorry I missed the scsi lists on the summary patch.
> While browsing the code I found another spot in mmc layer which
> needs fixing. The patch is at the end of the email with Chris
> and linux-mmc cc'ed here.

Would you mind putting them all in the patch system, I can add the acks
should anyone supply them later, and I'll repost them along with my set
of dma-mask patches.  Thanks.

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