[PATCH v2 0/2] ARM: decompressor: support AUTO_ZRELADDR and appended DTB

[Christian Marangi]

On Wed, Feb 21, 2024 at 05:57:00PM +0100, Christian Marangi wrote:
> On Sun, Jan 21, 2024 at 09:29:32PM +0100, Christian Marangi wrote:
> > This series try to address a long lasting problem with legacy device
> > that require an appended DTB and the use of AUTO_ZRELADDR.
> > 
> > With these device AUTO_ZRELADDR is not possible if for some reason at
> > the start of the RAM it's needed to reserve some space. (example qcom SoC
> > that allocate reserved space for SMEM)
> > 
> > In the current implementation with appended DTB and AUTO_ZRELADDR,
> > the memory start is only derived from the PC register and it can't be
> > changed by declaring additional info in the DTS.
> > 
> > In a normal setup, we have an intentional undocumented chosen property
> > to handle this and the memory node to declare the start of the memory.
> > 
> > With this applied and ARM_ATAG_DTB_COMPAT_IGNORE_MEM enabled (more 
> > info in the related patch) ipq806x can boot right away with AUTO_ZRELADDR
> > enabled and a correct memory node defined in DTS.
> > 
> > It's needed to ignore MEM ATAGs as most of the time the values from the
> > bootloader are hardcoded and OEM didn't care to actually provide them
> > resulting in funny situation where a Netgear R7800 with 512Mb of RAM
> > have Uboot passing 1.7GB of RAM with ATAGS.
> > 
> > While MEM ATAG may be broken, other ATAG like serial number or bootargs
> > might still be useful for partition declaration (cmdlinepart) or other
> > info hence DTB_COMPAT is still needed in these case and can't be
> > disabled.
> > 
> > I'm open to any suggestion on how this can be improved and I would love
> > some additional testing on other legacy platform but I assume this will
> > permit many legacy device to be correctly supported without having to
> > hardcode address.
> > 
> > Changes v2:
> > - Add Review and Ack Tags
> > - Use IS_ENABLED instead of global variable
> > 
> > Christian Marangi (2):
> >   ARM: decompressor: support memory start validation for appended DTB
> >   ARM: decompressor: add option to ignore MEM ATAGs
> > 
> >  arch/arm/Kconfig                        | 12 ++++++++++++
> >  arch/arm/boot/compressed/atags_to_fdt.c |  4 ++++
> >  arch/arm/boot/compressed/head.S         | 22 ++++++++++++++++++++++
> >  3 files changed, 38 insertions(+)
> > 
> >
> 
> Any news for this?

Sorry for asking again... but any news for this?

I have also added the 2 patch here [1] [2].

Been in incoming from a long time and I have seen other patch getting
accepted. Did I do something wrong in submitting the 2 patch?

[1] https://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=9394/1
[2] https://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=9395/1

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