[U-Boot] [PATCH sunxi-tools v2 0/2] Support unified u-boot SPL for SD cards and FEL mode

[Siarhei Siamashka]

On Tue, 10 Feb 2015 09:21:59 +0100
Hans de Goede <hdegoede at redhat.com> wrote:

> Hi,
> 
> On 09-02-15 03:37, Siarhei Siamashka wrote:
> > An updated variant of the older patch
> >      http://lists.denx.de/pipermail/u-boot/2015-February/204024.html
> >
> > These patches are not for the u-boot code (unless u-boot decides to
> > cannibalize the 'fel' tool later) but still provide a glue layerHi,
> > between the Allwinner BROM code and the u-boot SPL code. And need
> > to play nice with both of them.
> >
> > The updated 'fel' tool is supposed to be used together with u-boot
> > v2015.04 and provide support for booting regular u-boot SPL binaries
> > over USB via FEL mode. So that a special u-boot sunxi FEL configuration
> > can be eventually dropped in the future.
> >
> > The usage instructions are in the 'New method of booting u-boot over USB
> > (u-boot v2015.04 and later versions)' section of the linux-sunxi wiki page
> >      http://linux-sunxi.org/index.php?title=FEL/USBBoot&oldid=12979
> >
> > It temporarily moves the BROM data from the first 32 KiB of SRAM into
> > a different SRAM section before calling the SPL code. And then moves
> > it back before returning from the SPL back to the FEL code in BROM.
> > This provides a contiguous 32 KiB block in the beginning of SRAM for
> > use by the SPL. And in the case if an extra SRAM section is not
> > available, we can at least "defragmemnt" the free memory areas
> > and still provide a contiguous ~21 KiB block to the SPL in the
> > beginning of SRAM.
> >
> > This code is also available in the following branch:
> >      https://github.com/ssvb/sunxi-tools/commits/20150206-fel-large-spl-support
> >
> > Siarhei Siamashka (2):
> >    fel: Split 'aw_fel_get_version' into 'get' and 'print' variants
> >    fel: New command for loading U-Boot SPL binaries in eGON format
> >
> >   fel-to-spl-thunk.S | 172 +++++++++++++++++++++++++++++++
> >   fel-to-spl-thunk.h |  69 +++++++++++++
> >   fel.c              | 291 +++++++++++++++++++++++++++++++++++++++++++++++++----
> >   3 files changed, 510 insertions(+), 22 deletions(-)
> >   create mode 100644 fel-to-spl-thunk.S
> >   create mode 100644 fel-to-spl-thunk.h
> 
> Thanks for your work on this, ACK to both patches, feel free to push them.

Thanks, pushed to sunxi-tool

> One question, the new wiki instructions say that for the latest upstream u-boot
> _felconfig is no longer necessary, but Simon's patches to fix FEL support upstream
> contain some #ifdef FEL in start.S to skip some lowlevel init when in FEL mode,
> does that mean that skipping this is no longer necessary ?

Skipping is not necessary if we save/restore some additional registers
instead. I'm just applying extra changes on top of Simon's patches,
and it works (the wiki page links to the git branch with these
changes). This is discussed at

    http://lists.denx.de/pipermail/u-boot/2015-February/204361.html

-- 
Best regards,
Siarhei Siamashka