[PATCH 7/7] verdin-imx8mp_defconfig: Enable PCIe/NVMe support

[Sumit Garg]

On Wed, 21 Feb 2024 at 15:06, Fathi Boudra <fathi.boudra at linaro.org> wrote:
>
> Hi,
>
> On Wed, 21 Feb 2024 at 10:19, Marcel Ziswiler
> <marcel.ziswiler at toradex.com> wrote:
> >
> > Hi Sumit
> >
> > On Wed, 2024-02-21 at 08:55 +0100, Francesco Dolcini wrote:
> > > Hello Sumit,
> > >
> > > On Tue, Feb 20, 2024 at 06:40:56PM +0530, Sumit Garg wrote:
> > > > Also, enable reset driver which is a prerequisite for PCIe support.
> > > >
> > > > Signed-off-by: Sumit Garg <sumit.garg at linaro.org>
> > > > ---
> > > >  configs/verdin-imx8mp_defconfig | 9 +++++++++
> > > >  1 file changed, 9 insertions(+)
> > > >
> > > > diff --git a/configs/verdin-imx8mp_defconfig b/configs/verdin-imx8mp_defconfig
> > > > index 22b8a334dfa..d8bd644322b 100644
> > > > --- a/configs/verdin-imx8mp_defconfig
> > > > +++ b/configs/verdin-imx8mp_defconfig
> > > > @@ -185,3 +185,12 @@ CONFIG_USB_GADGET_VENDOR_NUM=0x1b67
> > > >  CONFIG_USB_GADGET_PRODUCT_NUM=0x4000
> > > >  CONFIG_IMX_WATCHDOG=y
> > > >  CONFIG_HEXDUMP=y
> > > > +CONFIG_DM_RESET=y
> > > > +CONFIG_RESET_IMX=y
> > > > +CONFIG_PCI=y
> > > > +CONFIG_PCIE_DW_IMX8=y
> > > > +CONFIG_PHY_IMX8M_PCIE=y
> > > > +CONFIG_CMD_PCI=y
> > > > +CONFIG_NVME=y
> > > > +CONFIG_NVME_PCI=y
> > > > +CONFIG_CMD_NVME=y
> > >
> > > This will increase the u-boot proper size
> >
> > Yes, I checked and it is actually slightly more than 32 K.
> >
> > > and marginally increase the
> > > boot time (because of a bigger binary to be read from the eMMC).
> >
> > That was also my concern.
> >
> > > Apart of that do you expect any other impact on those changes? SPL
> > > binary size should not be affected, correct?
> > >
> > > Asking this out loudly to confirm that nothing unexpected is going to
> > > happen because of these changes.
> >
> > Other than that I actually gave it a quick try and PCIe/NVMe does indeed work and the regular boot is not
> > affected (other than the slight size and boot time increase, of course).

Thanks for taking the time to test it. I suppose I can take that as a
Tested-by tag.

> >
> > > For my curiosity, care to share what's the use case? Do you plan to have
> > > the OS stored into an NVME device?
> >
> > For us the question is basically whether that use case does mandate enforcing such changes for each and every
> > customer.

> > Plus the regular expected maintenance effort any such change brings with it, of course.

>From a PCIe maintenance point of view, I can add myself as a
maintainer for drivers added by this patch-set.

>
> @Francesco that's correct, we have the OS stored on NVME SSD.
> @Marcel wrt enforcing it, we can always fallback to have a config
> fragment for our customers builds.
> That's already the case, we fine tune the config and don't use U-Boot
> defconfig out of the box for shipping to end users.
>

Marcel, Francesco,

If you folks still have worries about updating the defconfig then I
can make it as a config fragment for mainline too. I suppose that
should work for other boards too based on the iMX8MP SoC.

-Sumit

> > > Francesco
> >
> > Cheers
> >
> > Marcel
>
> Cheers,
> --
> Fathi Boudra