lkml.org 
[lkml]   [2020]   [Sep]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 07/18] 53c700: improve non-coherent DMA handling
On Tue, Sep 15, 2020 at 05:51:11PM +0200, Christoph Hellwig wrote:
> Switch the 53c700 driver to only use non-coherent descriptor memory if it
> really has to because dma_alloc_coherent fails. This doesn't matter for
> any of the platforms it runs on currently, but that will change soon.
>
> To help with this two new helpers to transfer ownership to and from the
> device are added that abstract the syncing of the non-coherent memory.
> The two current bidirectional cases are mapped to transfers to the
> device, as that appears to what they are used for. Note that for parisc,
> which is the only architecture this driver needs to use non-coherent
> memory on, the direction argument of dma_cache_sync is ignored, so this
> will not change behavior in any way.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
> drivers/scsi/53c700.c | 113 +++++++++++++++++++++++-------------------
> drivers/scsi/53c700.h | 17 ++++---
> 2 files changed, 72 insertions(+), 58 deletions(-)

Tested-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

--
Crap can work. Given enough thrust pigs will fly, but it's not necessarily a
good idea. [ RFC1925, 2.3 ]

\
 
 \ /
  Last update: 2020-09-22 12:56    [W:0.176 / U:2.704 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site