I use ptxdist + oselas BSP for the Phytec PXA270. I need to have a real time SSP interrupt in 16 bit spi mode. Sometimes, my SPI handler is delayed of 25µs to 170µs. It seen that is the delay PXA Timer tick that can be itnerrupted (SA_INTERRUPT option on the timer 0 handler ).
I suppose that that is due to the fact the kernel is only compile in PREMPT and is not a true real time kernel , but 170µs seem to be very long time for the timer interrupt ... My kernel is is a Linux phyCORE-PXA270 2.6.17-pcm027-3 #3 PREEMPT Is-it normal that the irq PXA Timer tick can take up to 170µs ? Can you advise me to patch the ptxdist / oselas PXA270 kernel to have real time interrupt ? Nicolas -- ptxdist mailing list ptxdist@pengutronix.de