On 25-07-25, 16:20, Jyothi Kumar Seerapu wrote: > > > On 7/23/2025 12:45 PM, Vinod Koul wrote: > > On 22-07-25, 15:46, Dmitry Baryshkov wrote: > > > On Tue, Jul 22, 2025 at 05:50:08PM +0530, Jyothi Kumar Seerapu wrote: > > > > On 7/19/2025 3:27 PM, Dmitry Baryshkov wrote: > > > > > On Mon, Jul 07, 2025 at 09:58:30PM +0530, Jyothi Kumar Seerapu wrote: > > > > > > On 7/4/2025 1:11 AM, Dmitry Baryshkov wrote: > > > > > > > On Thu, 3 Jul 2025 at 15:51, Jyothi Kumar Seerapu > > > > [Folks, would be nice to trim replies] > > > > > > > > Could you please confirm if can go with the similar approach of > > > > > > unmap the > > > > > > processed TREs based on a fixed threshold or constant value, > > > > > > instead of > > > > > > unmapping them all at once? > > > > > > > > > > I'd still say, that's a bad idea. Please stay within the boundaries of > > > > > the DMA API. > > > > > > > > > I agree with the approach you suggested—it's the GPI's responsibility to > > > > manage the available TREs. > > > > > > > > However, I'm curious whether can we set a dynamic watermark value > > > > perhaps > > > > half the available TREs) to trigger unmapping of processed TREs ? This > > > > would > > > > allow the software to prepare the next set of TREs while the hardware > > > > continues processing the remaining ones, enabling better parallelism and > > > > throughput. > > > > > > Let's land the simple implementation first, which can then be improved. > > > However I don't see any way to return 'above the watermark' from the DMA > > > controller. You might need to enhance the API. > > > > Traditionally, we set the dma transfers for watermark level and we get a > > interrupt. So you might want to set the callback for watermark level > > and then do mapping/unmapping etc in the callback. This is typical model > > for dmaengines, we should follow that well > > > > BR > > Thanks Dmitry and Vinod, I will work on V7 patch for submitting the I2C > messages until they fit and and unmap all processed messages together for > now. > > Regarding the watermark mechanism, looks GENI SE DMA supports watermark > interrupts but it appears that GPI DMA doesn't have such provision of > watermark.
What is the mechanism to get interrupts from the GPI? If you submit 10 txn, can you ask it to interrupt when half of them are done? -- ~Vinod
