[PATCH v3 00/15] Add support for MediaTek MT7621 SoC

[Marek Behún]

On Sat, 30 Apr 2022 21:31:15 +0800
Weijie Gao <weijie.gao at mediatek.com> wrote:

> On Fri, 2022-04-29 at 17:13 +0200, Marek Behún wrote:
> > On Fri, 29 Apr 2022 15:59:44 +0800
> > Weijie Gao <weijie.gao at mediatek.com> wrote:
> >   
> > > On Fri, 2022-04-29 at 08:15 +0200, Stefan Roese wrote:  
> > > > Hi Weijie
> > > > 
> > > > On 4/29/22 03:23, Weijie Gao wrote:    
> > > > > Hi Marek,
> > > > > 
> > > > > Yes. MT7621 does need such a proprietary binary for DDR
> > > > > initialization
> > > > > and calibration. That's why I submit only the ram-bootable part
> > > > > here.
> > > > > 
> > > > > I'm considering to create a preloader to load and run DDR
> > > > > init&calib
> > > > > binary and ram-bootable u-boot image. The ram-bootable u-boot
> > > > > image
> > > > > can be appended to the proloader to form the flash-bootable
> > > > > bootloader.
> > > > > 
> > > > > The source code of preloader will be uploaded to github.    
> > > > 
> > > > Just to be sure: You are not implementing this preloader as an U-
> > > > Boot
> > > > SPL loader, as this would conflict with U-Boot's GPL
> > > > compatibility?    
> > > 
> > > Yes. Submitting the source code of this binary also violates MTK's
> > > non-
> > > disclosure agreement.  
> > 
> > Isn't it possible to submit the DDR training code in binary version,
> > and somehow call into it from SPL?  
> 
> It's possible and I've already implemented it. But will u-boot accept
> binary file?

U-Boot at least accepts drivers that require proprietary firmware to
load (bnxt driver, for example).

I don't know whether a binary firmware can be accepted into the U-Boot
repository, whether in a separate file or as an u8 array in a .c file,
but it should at least be possible to make it so that the user can
compile it thsemsevles to be bundled, i.e. create a Kconfig option that
configures a path to the firmware. If it is present, it will be
compiled with DDR training bundled.

Stefan, Tom, can this be done?

BTW, Weijie, can I already test this on mt7621 board, also with DDR
training? Can you send me the patch that adds calling the proprietary
code?

Marek