Re: [RFC] Future TTM DMA direction

2012-01-25 Thread Thomas Hellstrom
OK, revisiting this again, please see inline below, On 01/10/2012 06:46 PM, Jerome Glisse wrote: On Mon, Jan 09, 2012 at 11:11:06AM +0100, Daniel Vetter wrote: On Mon, Jan 09, 2012 at 10:37:28AM +0100, Thomas Hellstrom wrote: Hi! When TTM was originally written, it was assumed that GPU apert

Re: [RFC] Future TTM DMA direction

2012-01-10 Thread Jerome Glisse
On Mon, Jan 09, 2012 at 11:11:06AM +0100, Daniel Vetter wrote: > On Mon, Jan 09, 2012 at 10:37:28AM +0100, Thomas Hellstrom wrote: > > Hi! > > > > When TTM was originally written, it was assumed that GPU apertures > > could address pages directly, and that the CPU could access those > > pages with

Re: [RFC] Future TTM DMA direction

2012-01-10 Thread Konrad Rzeszutek Wilk
On Mon, Jan 09, 2012 at 10:37:28AM +0100, Thomas Hellstrom wrote: > Hi! > > When TTM was originally written, it was assumed that GPU apertures > could address pages directly, and that the CPU could access those > pages without explicit synchronization. The process of binding a > page to a GPU tran

Re: [RFC] Future TTM DMA direction

2012-01-10 Thread Daniel Vetter
Hi Thomas, On Mon, Jan 09, 2012 at 12:01:28PM +0100, Thomas Hellstrom wrote: > Thanks for your input. I think this is mostly orthogonal to dma_buf, and > really a way to adapt TTM to be DMA-api aware. That's currently done > within the TTM backends. CMA was mearly included as an example that > mig

Re: [RFC] Future TTM DMA direction

2012-01-09 Thread Thomas Hellstrom
On 01/09/2012 11:11 AM, Daniel Vetter wrote: On Mon, Jan 09, 2012 at 10:37:28AM +0100, Thomas Hellstrom wrote: Hi! When TTM was originally written, it was assumed that GPU apertures could address pages directly, and that the CPU could access those pages without explicit synchronization. The

Re: [RFC] Future TTM DMA direction

2012-01-09 Thread Daniel Vetter
On Mon, Jan 09, 2012 at 10:37:28AM +0100, Thomas Hellstrom wrote: > Hi! > > When TTM was originally written, it was assumed that GPU apertures > could address pages directly, and that the CPU could access those > pages without explicit synchronization. The process of binding a > page to a GPU tran