Re: [PATCH v2 3/6] rng: add Microchip PolarFire SoC hardware RNG driver

["Jamie.Gibbons--- via U-Boot" <u-boot@lists.u-boot-project.org>]

Hi Leo,

On Mon, 2026-07-27 at 15:14 +0800, Leo Liang wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you
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> 
> Hi Jamie,
> 
> On Thu, Jul 23, 2026 at 8:52 AM Jamie Gibbons
> <jamie.gibbons@microchip.com> wrote:
> > 
> > Add a U-Boot RNG driver for Microchip's PolarFire SoC (MPFS). The
> > hardware RNG is accessed indirectly via the MPFS system controller
> > using
> > the mailbox interface.
> > 
> > The driver implements the UCLASS_RNG interface, requesting random
> > data
> > from the system controller and returning it to the caller.
> > 
> > This allows use of the PolarFire SoC hardware RNG via the
> > standard 'rng' command and DM RNG API.
> > 
> > Signed-off-by: Jamie Gibbons <jamie.gibbons@microchip.com>
> > ---
> >  drivers/rng/Kconfig    |   7 +++
> >  drivers/rng/Makefile   |   1 +
> >  drivers/rng/mpfs_rng.c | 101
> > +++++++++++++++++++++++++++++++++++++++++
> >  3 files changed, 109 insertions(+)
> >  create mode 100644 drivers/rng/mpfs_rng.c
> > 
> > diff --git a/drivers/rng/Kconfig b/drivers/rng/Kconfig
> > index 19b2b707677..856ffda2f5e 100644
> > --- a/drivers/rng/Kconfig
> > +++ b/drivers/rng/Kconfig
> > @@ -23,6 +23,13 @@ config RNG_MESON
> >           Enable support for hardware random number generator
> >           of Amlogic Meson SoCs.
> > 
> > +config RNG_MPFS
> > +       tristate "Microchip PolarFire SoC Random Number Generator
> > support"
> 
> Is there a special reason to use 'tristate' instead of 'bool'?
> If not, I could convert it to 'bool' when merging the patch,
> so you don't have to respin the patchset.

No, I don't believe there is a reason - this is a mistake. If you could
fix this on merge, that would be great.

Much appreciated,
Jamie.
> 
> Reviewed-by: Leo Yu-Chi Liang <leo.liang@sifive.com>
> 
> Best regards,
> Leo
> 
> > +       depends on DM_RNG && MPFS_SYSCONTROLLER
> > +       help
> > +         Enable support for hardware random number generator
> > +         of Microchip's PolarFire SoCs.
> > +