diff options
| -rw-r--r-- | drivers/tty/serial/omap-serial.c | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c index a2a529994ba5..3bbc4b5b6245 100644 --- a/drivers/tty/serial/omap-serial.c +++ b/drivers/tty/serial/omap-serial.c @@ -1234,6 +1234,61 @@ out: #ifdef CONFIG_SERIAL_OMAP_CONSOLE +#ifdef CONFIG_SERIAL_EARLYCON +static unsigned int __init omap_serial_early_in(struct uart_port *port, + int offset) +{ + offset <<= port->regshift; + return readw(port->membase + offset); +} + +static void __init omap_serial_early_out(struct uart_port *port, int offset, + int value) +{ + offset <<= port->regshift; + writew(value, port->membase + offset); +} + +static void __init omap_serial_early_putc(struct uart_port *port, int c) +{ + unsigned int status; + + for (;;) { + status = omap_serial_early_in(port, UART_LSR); + if ((status & BOTH_EMPTY) == BOTH_EMPTY) + break; + cpu_relax(); + } + omap_serial_early_out(port, UART_TX, c); +} + +static void __init early_omap_serial_write(struct console *console, + const char *s, unsigned int count) +{ + struct earlycon_device *device = console->data; + struct uart_port *port = &device->port; + + uart_console_write(port, s, count, omap_serial_early_putc); +} + +static int __init early_omap_serial_setup(struct earlycon_device *device, + const char *options) +{ + struct uart_port *port = &device->port; + + if (!(device->port.membase || device->port.iobase)) + return -ENODEV; + + port->regshift = 2; + device->con->write = early_omap_serial_write; + return 0; +} + +OF_EARLYCON_DECLARE(omapserial, "ti,omap2-uart", early_omap_serial_setup); +OF_EARLYCON_DECLARE(omapserial, "ti,omap3-uart", early_omap_serial_setup); +OF_EARLYCON_DECLARE(omapserial, "ti,omap4-uart", early_omap_serial_setup); +#endif /* CONFIG_SERIAL_EARLYCON */ + static struct uart_omap_port *serial_omap_console_ports[OMAP_MAX_HSUART_PORTS]; static struct uart_driver serial_omap_reg; |