Re: [PATCH RFC] media: em28xx: don't use coherent buffer for DMA transfers

2018-03-01 Thread Mauro Carvalho Chehab
Em Wed, 28 Feb 2018 09:49:12 -0500 Devin Heitmueller escreveu: > On Tue, Feb 27, 2018 at 12:42 PM, Mauro Carvalho Chehab > wrote: > > While coherent memory is cheap on x86, it has problems on > > arm. So, stop using it. > > > > Signed-off-by: Mauro Carvalho Chehab > > --- > > > > I wrote this p

Re: [PATCH RFC] media: em28xx: don't use coherent buffer for DMA transfers

2018-02-28 Thread Devin Heitmueller
On Tue, Feb 27, 2018 at 12:42 PM, Mauro Carvalho Chehab wrote: > While coherent memory is cheap on x86, it has problems on > arm. So, stop using it. > > Signed-off-by: Mauro Carvalho Chehab > --- > > I wrote this patch in order to check if this would make things better > for ISOCH transfers on Ra

[PATCH RFC] media: em28xx: don't use coherent buffer for DMA transfers

2018-02-27 Thread Mauro Carvalho Chehab
While coherent memory is cheap on x86, it has problems on arm. So, stop using it. Signed-off-by: Mauro Carvalho Chehab --- I wrote this patch in order to check if this would make things better for ISOCH transfers on Raspberry Pi3. It didn't. Yet, keep using coherent memory at USB drivers seem an