Re: [PATCH 00/17] arm: semihosting: Cleanups and new features

[Andre Przywara <andre.przywara@arm.com>]

On Thu, 10 Mar 2022 11:48:50 -0500
Sean Anderson <sean.anderson@seco.com> wrote:

Hi,

> On 3/4/22 1:46 PM, Tom Rini wrote:
> > On Fri, Mar 04, 2022 at 12:19:27PM -0500, Sean Anderson wrote:  
> >> Hi Andre,
> >> 
> >> On 3/4/22 6:47 AM, Andre Przywara wrote:  
> >> > On Fri, 4 Mar 2022 02:06:03 +0100
> >> > Linus Walleij <linus.walleij@linaro.org> wrote:
> >> > 
> >> > Hi,
> >> > 
> >> > Linus, thanks for the heads up, much appreciated!
> >> >   
> >> >> On Thu, Mar 3, 2022 at 9:44 PM Sean Anderson <sean.anderson@seco.com> wrote:
> >> >>   
> >> >> > The main device affected by these changes is vexpress64, so I'd appreciate
> >> >> > if Linus (or anyone else) could try booting.    
> >> > 
> >> > As it happens, I am sitting on a series updating vexpress_aemv8a_semi, and
> >> > letting it use OF_CONTROL. I will send this ASAP.
> >> > As it turned out, the automatic semihosting boot command is actually broken
> >> > in v2022.01, the fix is the first patch in my series. This clashes with
> >> > this series, but it's easy to resolve.  
> >> 
> >> I, for one, appreciate that the boot command is no longer all one line after
> >> your series.
> >> 
> >> Simon/Tom, which series would you like to be based off the other?  
> > 
> > I think it's however it's easiest for you two to collaborate.  
> 
> I think it will be cleaner for me to base my series on his, but I just want to
> avoid having to rebase a lot :)

Yeah, it should just be this one line, though, right?
Tom, would you consider taking patch 01/11 now, as this fixes a
regression? The Sean could at least rebase on top of this. Rebasing on top
of the rest should be more straight-forward, because it's not one
super-long line anymore.

> 
> >> > From skimming over this series here, it looks quite nice, I especially love
> >> > promoting the semihosting load to a proper filesystem. The only drawback
> >> > seems to be that this will break existing scripts used by people in their
> >> > deployments, which rely on the smhload command. I don't really know if
> >> > there are actually any users doing so, but I guess we will find out.  
> >> 
> >> Yeah, I'm not sure what the stance on shell compatibility is. As I understand
> >> it, for the C API only in-tree users matter. However, shell commands are more
> >> of an "external" API, used by distro boot scripts. Simon/Tom, what's the
> >> process for this?  
> > 
> > Well, in this case we can be a bit more cavalier than typical because of
> > the very limited user base.  So long as we have good documentation

Yes, I agree. I don't think there are many users. The fact that it's
broken in v2022.01 and nobody complained so far tells you something. And I
can certainly handle a good part of the users internally here. I guess the
other half is in Linaro ;-)

Cheers,
Andre

> > around it including something around how to transition to the new
> > commands, it should be fine to do so, when the code is otherwise ready.  
> 
> OK, I will add some more documentation about transitioning to this series.
> 
> --Sean