serial: altera_jtaguart: add earlycon support

Nios2 currently uses its own early printk implementation, rather than
using unified earlycon support to show boot messages on altera_jtaguart
(and altera_uart for that matter).

Add earlycon support to altera_jtaguart so that other archs may use it. Also,
this will allow the early printk implementation in arch/nios2 to eventually be
removed in a future patch.

Cc: Ley Foon Tan <lftan@altera.com>
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Tobias Klauser 2017-03-14 14:11:25 +01:00 committed by Greg Kroah-Hartman
parent 47baf1ad81
commit 0dcc0542a0
2 changed files with 21 additions and 0 deletions

View File

@ -1343,6 +1343,7 @@ config SERIAL_ALTERA_JTAGUART_CONSOLE
bool "Altera JTAG UART console support"
depends on SERIAL_ALTERA_JTAGUART=y
select SERIAL_CORE_CONSOLE
select SERIAL_EARLYCON
help
Enable a Altera JTAG UART port to be the system console.

View File

@ -383,6 +383,26 @@ console_initcall(altera_jtaguart_console_init);
#define ALTERA_JTAGUART_CONSOLE (&altera_jtaguart_console)
static void altera_jtaguart_earlycon_write(struct console *co, const char *s,
unsigned int count)
{
struct earlycon_device *dev = co->data;
uart_console_write(&dev->port, s, count, altera_jtaguart_console_putc);
}
static int __init altera_jtaguart_earlycon_setup(struct earlycon_device *dev,
const char *options)
{
if (!dev->port.membase)
return -ENODEV;
dev->con->write = altera_jtaguart_earlycon_write;
return 0;
}
OF_EARLYCON_DECLARE(juart, "altr,juart-1.0", altera_jtaguart_earlycon_setup);
#else
#define ALTERA_JTAGUART_CONSOLE NULL