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

[Bin Meng]

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?

> +       help
> +         Select this to enable host transfer interface (HTIF) based serial
> +         console. The HTIF device is quite common in RISC-V emulators and
> +         RISC-V ISS so this driver allows using U-Boot on such platforms.
> +
>  config SIFIVE_SERIAL
>         bool "SiFive UART support"
>         depends on DM_SERIAL

Regards,
Bin