Re: [PATCH v2 2/2] misc: Add iop driver for Sunplus SP7021

[Greg KH <gregkh@linuxfoundation.org>]

On Mon, Dec 06, 2021 at 06:48:46AM +0000, Tony Huang 黃懷厚 wrote:
> Dear Greg KH, Arnd:
> 
> > -----Original Message-----
> > From: Greg KH <gregkh@linuxfoundation.org>
> > Sent: Friday, December 3, 2021 6:39 PM
> > To: Tony Huang <tonyhuang.sunplus@gmail.com>
> > Cc: derek.kiernan@xilinx.com; dragan.cvetic@xilinx.com; arnd@arndb.de;
> > linux-kernel@vger.kernel.org; robh+dt@kernel.org; devicetree@vger.kernel.org;
> > Wells Lu 呂芳騰 <wells.lu@sunplus.com>; Tony Huang 黃懷厚
> > <tony.huang@sunplus.com>
> > Subject: Re: [PATCH v2 2/2] misc: Add iop driver for Sunplus SP7021
> > 
> > On Fri, Dec 03, 2021 at 11:48:45AM +0800, Tony Huang wrote:
> > > IOP (IO Processor) embedded inside SP7021 which is used as Processor
> > > for I/O control, RTC wake-up and cooperation with CPU & PMC in power
> > > management purpose.
> > > The IOP core is DQ8051, so also named IOP8051, it supports dedicated
> > > JTAG debug pins which share with SP7021.
> > > In standby mode operation, the power spec reach 400uA.
> > >
> > > Signed-off-by: Tony Huang <tonyhuang.sunplus@gmail.com>
> > > ---
> > > Changes in v2:
> > >  - Addressed comments from Arnd Bergmann.
> > >  - Addressed comments from Greg KH.
> > >  - Addressed comments from kernel test robot.
> > >
> > >  MAINTAINERS                    |   1 +
> > >  drivers/misc/Kconfig           |   1 +
> > >  drivers/misc/Makefile          |   1 +
> > >  drivers/misc/iop/Kconfig       |  13 ++
> > >  drivers/misc/iop/Makefile      |   6 +
> > 
> > Why do you need a subdirectory for a single .c file?
> > 
> 
> 1. Currently my bin file is placed in the root file system. I need to
> wait for the kernel booting to succeed before loading the bin code.

What "bin file"?

> 2. In addition, I need the kernel booting process to be able to mount
> the iop module and load bin file.I need to put bin file in /iop.

That is an odd directory location.

> Do you have a good way to load bin code during kernel booting?

Is this firmware?  Put it in the normal location for firware that the
kernel expects to see.

thanks,

greg k-h