[PATCH 12/17] tty: New RISC-V SBI Console Driver

[Arnd Bergmann]

On Wed, Jun 7, 2017 at 9:15 AM, Geert Uytterhoeven <geert at linux-m68k.org> wrote:
> CC (hypervisor) console folks
>
> On Wed, Jun 7, 2017 at 1:00 AM, Palmer Dabbelt <palmer at dabbelt.com> wrote:
>> This patch adds a new driver for the console availiable via the RISC-V
>> SBI.  This console is specified to be used for early boot messages, and
>> is designed to be a very simple (albiet somewhat slow) console that is
>> always availiable.  All RISC-V systems have an SBI console.
>>
>> The SBI console is made availiable for early printk messages and is also
>> availiable as a regular console.
>>
>> Signed-off-by: Palmer Dabbelt <palmer at dabbelt.com>
>> ---
>>  drivers/tty/hvc/Kconfig   |  11 +++++
>>  drivers/tty/hvc/Makefile  |   1 +
>>  drivers/tty/hvc/hvc_sbi.c | 102 ++++++++++++++++++++++++++++++++++++++++++++++
>>  3 files changed, 114 insertions(+)
>>  create mode 100644 drivers/tty/hvc/hvc_sbi.c
>>
>> diff --git a/drivers/tty/hvc/Kconfig b/drivers/tty/hvc/Kconfig
>> index 574da15fe618..f3774adab240 100644
>> --- a/drivers/tty/hvc/Kconfig
>> +++ b/drivers/tty/hvc/Kconfig
>> @@ -114,4 +114,15 @@ config HVCS
>>           which will also be compiled when this driver is built as a
>>           module.
>>
>> +config HVC_SBI
>> +       bool "SBI console support"
>> +       depends on RISCV
>> +       select HVC_DRIVER
>> +       default y
>> +       help
>> +         This enables support for console output via RISC-V SBI calls, which
>> +         is normally used only during boot to output printk.
>> +
>> +         If you don't know what do to here, say Y.
>> +
>>  endif # TTY

Please move this a little higher along with the other HVC_DRIVER
implementations.

>> + * RISC-V SBI interface to hvc_console.c
>> + *  based on drivers-tty/hvc/hvc_udbg.c
>> + *
>> + * Copyright (C) 2008 David Gibson, IBM Corporation
>> + * Copyright (C) 2012 Regents of the University of California

2017?

        Arnd