Dear All,
We have a board with an i.MX8M Mini SoC connected to the TI SN65DSI86 via the DSI interface.
We are using v4.19.35 for the Linux kernel (rel_imx_4.19.35_1.0.0).
The monitor connected to the TI SN65DSI86 chip generally works OK at boot up (but not every single time), and we get intermittent problems while switching modelines at run time. The problems that we see are:
- black screen
- stripe at the top of the screen, the rest of the screen is black
- flickering
- dead monitor
When one of the aforementioned problems shows (mainly when switching resolution at run time, and occasionally at boot up), the TI SN65DSI86 chip reports LOSS_OF_DP_SYNC_LOCK_ERR (bit 6) from register 0xF6, which seems to indicate problems with the DSI interface. TheSN65DSI86 chip has a color bars generator that does not require the DSI interface, when generating color bars the monitor works all the time, with any of the resolution/timings supported by the monitor.
All seems to be pointing to issues with the DSI interface, but unfortunately I can't really take any measurements on those lines as the tracks go from the SoC straight to the bridge.
These issues are a bit puzzling, as they are intermittent, the same modeline might work or it might not work, and retrying the same modeline (via modetest) might fix or break the monitor.
Any idea on how to approach this?
Thanks,
Fab
