Hello guys,
I'm developing a driver for Sony imx492 sensor and i'm using imx8m-mini
(Variscite SoM on Symphony carrier board) platform. Thanks to Laurent i dumped
the vendor mipi-csi and csi-bridge drivers in favor of mainline (v5.19-rc6 atm)
and parts started to click in place. However, there are still a few rough
edges.
The sensor is 47mpix, and is only capable of streaming over all four CSI-2
lanes. Each lane is 1.728gbit, which makes 6.912gbps total bandwidth.
imx8m-mini's d-phy can handle (on paper) up to 6gbps.
I guess the main question here is: what's the fastest transfer rate that's known
to work with this SoC? Does anyone have experience with imx8m-mini in this
regard?
Even with the settings that i'm able to obtain a (distorted) test pattern image
with, i keep getting tons of:
[99910.847591] imx-mipi-csis 32e30000.mipi-csi: FIFO Overflow Error events: 1353347
IRQs also look a suspicious on the 'csi' part:
214: 2653716 0 0 0 GICv3 49 Level 32e30000.mipi-csi
215: 2 0 0 0 GICv3 48 Level csi
That's with this clock setup:
sys_pll2 1 1 0 1000000000 0 0 50000 Y
sys_pll2_out 5 5 0 1000000000 0 0 50000 Y
sys_pll2_1000m 3 3 0 1000000000 0 0 50000 Y
csi1_phy_ref 1 1 0 1000000000 0 0 50000 Y
csi1_core 1 1 0 500000000 0 0 50000 Y
csi1_root_clk 1 1 0 500000000 0 0 50000 Y
However, if i change the latter two (csi1_core & csi1_root_clk) to 1ghz, there
are still mipi-csi IRQs coming in, but nothing from the csi-bridge.
Any advice on where i shall start looking first?
thanks,
Petko
