Add early console support which relies on the bootloader for the
initialization of the UART.
Please note, that the compatibles are taken from at91-usart MFD
driver.
Signed-off-by: Michael Walle <michael@xxxxxxxx>
---
drivers/tty/serial/Kconfig | 1 +
drivers/tty/serial/atmel_serial.c | 24 ++++++++++++++++++++++++
2 files changed, 25 insertions(+)
diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index 0e5ccb25bdb1..407a98ec0791 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -139,6 +139,7 @@ config SERIAL_ATMEL_CONSOLE
bool "Support for console on AT91 serial port"
depends on SERIAL_ATMEL=y
select SERIAL_CORE_CONSOLE
+ select SERIAL_EARLYCON
help
Say Y here if you wish to use an on-chip UART on a Atmel
AT91 processor as the system console (the system
diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index 2d09a89974a2..73d43919898d 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -2673,6 +2673,30 @@ static struct console atmel_console = {
.data = &atmel_uart,
};
+static void atmel_serial_early_write(struct console *con, const char *s,
+ unsigned int n)
+{
+ struct earlycon_device *dev = con->data;
+
+ uart_console_write(&dev->port, s, n, atmel_console_putchar);
+}
+
+static int __init atmel_early_console_setup(struct earlycon_device *device,
+ const char *options)
+{
+ if (!device->port.membase)
+ return -ENODEV;
+
+ device->con->write = atmel_serial_early_write;
+
+ return 0;
+}
+
+OF_EARLYCON_DECLARE(atmel_serial, "atmel,at91rm9200-usart",
+ atmel_early_console_setup);
+OF_EARLYCON_DECLARE(atmel_serial, "atmel,at91sam9260-usart",
+ atmel_early_console_setup);
+
#define ATMEL_CONSOLE_DEVICE (&atmel_console)
#else
--
2.30.2
