Re: [PATCH v3 03/10] partitions: Introduce NVIDIA Tegra Partition Table

[Michał Mirosław]

On Tue, Mar 24, 2020 at 02:22:34AM +0300, Dmitry Osipenko wrote:
> 24.03.2020 00:35, MichaÅ MirosÅaw ÐÐÑÐÑ:
> > On Mon, Mar 23, 2020 at 10:59:52PM +0300, Dmitry Osipenko wrote:
> >> 23.03.2020 22:17, MichaÅ MirosÅaw ÐÐÑÐÑ:
> >>> On Mon, Mar 23, 2020 at 07:34:24PM +0300, Dmitry Osipenko wrote:
> >>>> All NVIDIA Tegra devices use a special partition table format for the
> >>>> internal storage partitioning. Most of Tegra devices have GPT partition
> >>>> in addition to TegraPT, but some older Android consumer-grade devices do
> >>>> not or GPT is placed in a wrong sector, and thus, the TegraPT is needed
> >>>> in order to support these devices properly in the upstream kernel. This
> >>>> patch adds support for NVIDIA Tegra Partition Table format that is used
> >>>> at least by all NVIDIA Tegra20 and Tegra30 devices.
> >>>>
> >>>> Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
> >>>> ---
> >>>>  arch/arm/mach-tegra/tegra.c   |  54 ++++
> >>> [...]
> >>>
> >>> Please split off this part and make the information available to
> >>> userspace (pt_addr + pt_size) if found. This would make it easier
> >>> to support use the partition table later in initrd instead.
> >>
> >> Please clarify what do you mean by "use the partition table later in
> >> initrd instead".
> > 
> > Configure device-mapper to span eMMC boot+data partitions and then ask
> > (modified) kpartx to partition the resulting device. All before rootfs
> > is mounted and switched to in initrd.
> 
> The whole point of this series is to make partition handling generic in
> the kernel, avoiding the need to customize anything.

Yes, but at least for diagnostic purposes, it would be nice to have the
values from BCT exposed somewhere in /sys.

Best Regards,
MichaÅ MirosÅaw