lkml.org 
[lkml]   [2010]   [Oct]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: A question about ZONE_DMA
Date
Am Mittwoch, 13. Oktober 2010, 16:52:41 schrieb Casey Dahlin:
> Hi all,
>
> So if I understand correctly, ZONE_DMA exists to separate and preserve the
> chunk of memory to which older ISA cards are capable of doing DMA. The question
> that arises for me is:
>
> 1) Why do /all/ 32-bit boxes have a ZONE_DMA when surely only a tiny and
> shrinking number of them have a need for it?

You don't know before you load the module of the driver that needs it.

> 2) Why do /any/ 64-bit boxes have a ZONE_DMA? Is there really some godless
> monster out there who put an early ISA bridge and a 64-bit CPU on the same
> motherboard?!

Parports can use DMA and are generally ISA.

Regards
Oliver


\
 
 \ /
  Last update: 2010-10-13 16:59    [W:0.037 / U:0.492 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site