Hi Sudeep and Olof,

Clock driver from same patch set uses ioctl API along with other clock eemi 
APIs. As clock patches' final review is pending by Stephen, Michal only created 
pull request for rest of the patches and that doesn't require ioctl api. I will 
remove it and submit new patch set.

For future patches which requires ioctl api, would like to understand your 
suggestion so I can make required changes. For zynqmp, EEMI interface allows 
clock, reset, power etc management through firmware but apart from those there 
are some operations which needs secure access through firmware. Examples are 
accessing some storage registers for inter agent communication, configuring 
another agent(RPU) mode, setting PLL parameters, boot device configuration etc. 
Those operations are covered as ioctls as they are very platform specific. Do 
you suggest to handle them with individual EEMI APIs instead of ioctl API?

Thanks,
Jolly Shah


> -----Original Message-----
> From: Olof Johansson [mailto:[email protected]]
> Sent: Tuesday, September 11, 2018 8:03 AM
> To: Jolly Shah <[email protected]>
> Cc: [email protected]; Ingo Molnar <[email protected]>; Greg Kroah-
> Hartman <[email protected]>; [email protected]; Sudeep
> Holla <[email protected]>; [email protected]; Kees Cook
> <[email protected]>; Dmitry Torokhov <[email protected]>;
> Michael Turquette <[email protected]>; Stephen Boyd
> <[email protected]>; Michal Simek <[email protected]>; Rob Herring
> <[email protected]>; Mark Rutland <[email protected]>; linux-clk
> <[email protected]>; Rajan Vaja <[email protected]>; Linux ARM
> Mailing List <[email protected]>; Linux Kernel Mailing List
> <[email protected]>; DTML <[email protected]>
> Subject: Re: [PATCH v11 03/11] firmware: xilinx: Add zynqmp IOCTL API for
> device control
> 
> Hi Jolly,
> 
> On Mon, Sep 10, 2018 at 12:17 PM, Jolly Shah <[email protected]> wrote:
> > Hi All,
> >
> > Adding more clarification on top of what Michal said:
> > Here ioctl is not a system ioctl and just a eemi API like other interface 
> > APIs. It
> cannot be called from userspace. Only Linux drivers can use this API for 
> defined
> ioctl operations. This API is meant for any platform specific operations which
> needs to be managed by firmware. Firmware will always validate the request for
> action being performed.
> > Debugfs interface is just for debugging during development. We can remove
> debugfs support for ioctl API if you suggest.
> 
> Are there any pending patchsets that make use of the ioctl interface besides 
> the
> debugfs piece? None of the ones in this pull request (besides the debugfs) 
> seems
> to call into it.
> 
> It might just be easier to leave it out until you have a use case for it. The 
> rest of
> the patchset looks fine to me, and I'd be happy to take it. Once you have a 
> need
> for it we can discuss specifics.
> 
> 
> -Olof

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