[U-Boot] [PATCH] ARM SOCFPGA: add resetmgr command so reset can be deasserted in bootcmd (for example on peripheral dma interfaces after fpga has been programmed).

[Frank Mori Hess]

Marek Vasut wrote:
> Please always CC the list. Do NOT top-post.

You do realize I was replying to an email you sent to my personal address and 
you didn't even send to the list?
 
> What is your goal here ?

To put things in context, my larger goal is to update u-boot from the old 
version altera integrates into Quartus to a reasonably recent version of 
mainline u-boot being provided by the distro we are using.  My naive hope was 
the new version of u-boot would work at least as well as the old altera one.  
Experience so far:  infinite reboot loop due to broken cadence driver:

https://lists.denx.de/pipermail/u-boot/2017-December/313470.html

No response except from author responsible for breaking the driver insisting 
his changes be kept.

And now: DMA peripheral requests for FPGA are non-functional due to mainline 
u-boot ignoring the reset_config.h in the handoff files generated by Quartus.  
Apparently, the mainline uboot position is that it is inappropriate to provide 
any more support for initializing the resets than providing the ability to 
write to memory addresses with "mw".
 
> 
> Going back to my initial question -- what is your usecase and your aim
> here ? Usually you use FPGA manager in Linux to load the FPGA.
> >> 
> >> But you can really just do mw to the correct address or create a U-Boot
> >> script , so this command is not really needed, is it ?
> 

Ok, I am running Linux on the board.  I don't see how it would help to load 
the FPGA from Linux rather than u-boot.  The dma peripheral requests would 
still be just as disabled.  The only difference would be that I would be 
forced to deassert the resets from Linux rather than u-boot, which I guess 
would make it not your problem?  In principle, the fpga manager provides a 
write_complete hook that the socfpga fpga manager could use to deassert resets 
(perhaps based on device tree settings), but looking at my 4.1.33 fpga/
socfpga.c it doesn't seem to.