[PATCH 1/3] serial: Add RISC-V HTIF console driver

[Bin Meng]

On Tue, Jan 25, 2022 at 2:00 PM Anup Patel <apatel at ventanamicro.com> wrote:
>
> On Tue, Jan 25, 2022 at 10:22 AM Bin Meng <bmeng.cn at gmail.com> wrote:
> >
> > On Sat, Jan 15, 2022 at 12:20 AM Anup Patel <apatel at ventanamicro.com> wrote:
> > >
> > > Quite a few RISC-V emulators and ISS (including Spike) have host
> > > transfer interface (HTIF) based console. This patch adds HTIF
> > > based console driver for RISC-V platforms which depends totally
> > > on DT node for HTIF register base address.
> > >
> > > Signed-off-by: Anup Patel <apatel at ventanamicro.com>
> > > Reviewed-by: Philipp Tomsich <philipp.tomsich at vrull.eu>
> > > ---
> > >  drivers/serial/Kconfig       |   8 ++
> > >  drivers/serial/Makefile      |   1 +
> > >  drivers/serial/serial_htif.c | 178 +++++++++++++++++++++++++++++++++++
> > >  3 files changed, 187 insertions(+)
> > >  create mode 100644 drivers/serial/serial_htif.c
> > >
> > > diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
> > > index 6c8fdda9a0..345d1881f5 100644
> > > --- a/drivers/serial/Kconfig
> > > +++ b/drivers/serial/Kconfig
> > > @@ -866,6 +866,14 @@ config PXA_SERIAL
> > >           If you have a machine based on a Marvell XScale PXA2xx CPU you
> > >           can enable its onboard serial ports by enabling this option.
> > >
> > > +config HTIF_CONSOLE
> > > +       bool "RISC-V HTIF console support"
> > > +       depends on DM_SERIAL && 64BIT
> >
> > Does this driver not work on 32-bit?
>
> Only putc() works but getc() does not work on 32-bit. Same issue
> is there with OpenSBI and BBL as well. That's why I have restricted
> this driver to 64-bit only.
>

I don't get it. Is this a QEMU riscv32 bug?

Regards,
Bin