lkml.org 
[lkml]   [2008]   [Nov]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [Q] Why does dma_alloc_coherent() of ia64 GFP_DMA?
On Tue, 11 Nov 2008, FUJITA Tomonori wrote:

> Is it because it does some kinda address translation
> (provider->dma_map_consistent) later? The zone flag is meaningless if
> you do sorta address translation (e.g. hardware IOMMU like VT-d).

Yes it can do address translation. Therefore a < 4G address can show up at
any 64 bit address. So no need for a special DMA zone. The same is true
for more x86_64 platforms that have an IOMMU.




\
 
 \ /
  Last update: 2008-11-11 21:35    [W:0.259 / U:0.452 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site