[U-Boot] [PATCH 4/9] ARM: socfpga: Bundle U-Boot fitImage into SFP on Arria10

[Chee, Tien Fong <tien.fong.chee@intel.com>]

On Mon, 2018-11-26 at 12:22 +0100, Marek Vasut wrote:
> On 11/26/2018 11:30 AM, Chee, Tien Fong wrote:
> > 
> > On Fri, 2018-11-23 at 13:40 +0100, Marek Vasut wrote:
> > > 
> > > On 11/23/2018 10:54 AM, Chee, Tien Fong wrote:
> > > > 
> > > > 
> > > > On Wed, 2018-11-21 at 15:21 +0100, Marek Vasut wrote:
> > > > > 
> > > > > 
> > > > > On 11/21/2018 11:41 AM, tien.fong.chee at intel.com wrote:
> > > > > > 
> > > > > > 
> > > > > > 
> > > > > > From: Tien Fong Chee <tien.fong.chee@intel.com>
> > > > > Did you change Author:ship of the patch ?
> > > I believe you did, so please fix that.
> > Very sorry. I din't realize the author name was changed.
> Please be careful next time.
Sure.
> 
> > 
> > > 
> > > 
> > > > 
> > > > 
> > > > > 
> > > > > 
> > > > > > 
> > > > > > 
> > > > > > Bundle U-Boot fitImage containing U-Boot and FPGA bitstream
> > > > > > into
> > > > > > the
> > > > > > u-boot-with-spl.sfp on Arria10. This lets U-Boot operate in
> > > > > > a
> > > > > > very
> > > > > > similar fashion to Gen5, where the U-Boot binary got loaded
> > > > > > by
> > > > > > the
> > > > > > SPL from a uImage concatenated at the end of the SPL SFP
> > > > > > image.
> > > > > > On
> > > > > > Gen10, the U-Boot is in fitImage which contains the FPGA
> > > > > > bitstream
> > > > > > as well. In this case, the SPL can load the FPGA bitstream
> > > > > > first
> > > > > > and
> > > > > > load the U-Boot afterward in the same manner. This is
> > > > > > nonetheless a
> > > > > > stopgap measure until there is a proper firmware loader in
> > > > > > U-
> > > > > > Boot.
> > > > > Right, this is a stopgap measure until FW loader is present.
> > > > > Why
> > > > > is
> > > > > this
> > > > > patch needed at all in this series ?
> > > > This patch is cherry picked from the sdmmc_next custodian, so
> > > > this
> > > > patch is required for generating FIT image. I can remove the
> > > > stopgap
> > > > comment to avoid confusing.
> > > But why is this patch needed at all ? You use the firmware loader
> > > to
> > > load the FPGA bitstream. Where does the fitImage come into play ?
> > > 
> > > The fitImage was used to circumvent the missing FW loader, when I
> > > needed
> > > to load multiple files (bitstream and u-boot binary). Now there
> > > is no
> > > such requirement anymore, so the entire fitImage machinery is
> > > probably
> > > not needed ?
> > Loading issue is not the reason we choose the fitImage. We choose
> > it
> > because it allows more flexibility in handling various type images,
> > especially it allows user more choices to enhance integrity and
> > security protection.
> Do you need to load multiple images at all ? Do you need the extra
> flexibility or does it only bloat and slow down the boot process for
> no
> benefit at all? If a user needs it, they can enable it, but do we
> need
> it by default ?
Okay, then we add in the fitImage support and let user to enable it.
So, without CONFIG_SPL_FIT is defined, then the boot process would be
with individual files such as u-boot-dtb.img instead of u-boot.itb.
> 
> > 
> > Although we plan to use fitImage as our default implementation, but
> > this series of patches are still allow fw loading individual
> > bitstream
> > image in filesystem partition. So, it is up to user to made the
> > choice.
> Right, so is the fitImage needed at all ?
>