Hi Hyunwoong, On 12/08/2010 08:12 AM, Hyunwoong Kim wrote: > Hello, > > I am writing this mail to suggest one thing regarding FIMC H/W setting. > You wrote the below code for setting S5P_MSCTRL_FRAME_COUNT as one. > > cfg |= (S5P_MSCTRL_FRAME_COUNT(1) | S5P_MSCTRL_INPUT_MEMORY); > > I think it’s better way to set the value of S5P_MSCTRL_FRAME_COUNT as 4. > Because, this value means input DMA burst count. > The default value of input DMA burst count in FIMC is 4. > And I guess if the value of less than 4 is set as input DMA burst count, > the performance of input DMA in FIMC will be lower. > > I want to know how about your opinions.
I did a test with the input DMA burst value of 1 and 4 and didn't observe an improvement in the image processing time. I guess it could show up when the system bus is heavily loaded or with HD input image size or bigger. The datasheet is not too verbose about this parameter, I am also not sure if it has any impact on the input pixel size alignment. I'm considering making a patch changing input DMA burst count to the default value and I've also noticed that S5P_MSCTRL_FRAME_COUNT_MASK is 3 instead of 0xF. Thank you for review. Regards, -- Sylwester Nawrocki Samsung Poland R&D Center -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
