Hi Guys,
I have a slave when I connected it to the spi of the hikey, it is behaving weird.
But when I connect my device to the i2c, it is working fine.
When I used the spi frequency as 11MHz I faced issue, so I moved to 4MHz to solve it.
Is the spi don’t support bulk write or is it has some kind of issues?
I am currently debugging this one.
Do you guys have any information that I can use to do the things faster?
What is the freq on i2c? Also 11MHz?
The hikey uses pl022 for spi and based on the pl022 spec [1], freq = clock / (cpsdvr * (1 + scr)). If my calcs are right, the clock is 150mhz [2] and the minimum for cpsdvr and scr is 2 and 0 respectively, giving us a max freq of 75mhz, so 11mhz should be ok. That said, I’ve never really tried anything beyond 500khz (default in spidev_test). Perhaps you can try spidev_test first with a higher speed to see if it works?
[1] http://infocenter.arm.com/help/topic/com.arm.doc.ddi0194g/DDI0194G_ssp_pl022_r1p3_trm.pdf
[2] http://lxr.free-electrons.com/source/drivers/clk/hisilicon/clk-hi6220.c#L135
