On 9/1/2017 8:47 AM, Michael Brown wrote: > > But I have tested what happens when you have the display running (linux > desktop) and then try to reconfigure the fpga with the same bitfile as > loaded by uboot. > > Result is a blank screen....
You're lucky. You can easily wedge the entire system doing this. > THis illustrates that loading/running a different bitfile / machinekit > configuration will allways require a reboot when using the local soc > display. Yep. > 1 --> It may be possible to remedy this by reloading the alt_vip_fb driver > (loaded as module), and resetting / restarting the x-server. ? Possible, but quite a hassle. > 2 --> I have spent some time studying the partial-fpga-reconfiguration docs > and it looks doable for me to create a partitioned design with. > the main partition containing the display and other qsys cores + - the uio. > and a freezable bridge > + 1 new partition for each hm2 config. This is *SERIOUSLY* challenging and very limiting for the logic going into the FPGA (placement and routing for the display driver has to be locked down and can't be moved to accommodate the hm2 recompiles, this also prohibits logic optimization between the partitions). IMHO, requiring a reboot to change the FPGA configuration when it's loaded by U-Boot is a minor inconvenience. Considering the equivalent with actual Mesa hardware is running the "mesaflash" utility (which also requires a full power down, not just a reboot!) requiring a reboot is fine. ...but since it's already working, I think programming the FPGA via overlays should remain supported for folks who aren't trying to use things like HDMI. -- Charles Steinkuehler [email protected] -- website: http://www.machinekit.io blog: http://blog.machinekit.io github: https://github.com/machinekit --- You received this message because you are subscribed to the Google Groups "Machinekit" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. Visit this group at https://groups.google.com/group/machinekit. For more options, visit https://groups.google.com/d/optout.
