serial: fsl_lpuart: add earlycon support
Add support for DT and command line based earlycon support for
lpuart and lpuart32 used on Freescale Vybrid and and QorIQ LS1021A
processors.
Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 22a4b68..8d9dd53 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1023,6 +1023,13 @@
serial port must already be setup and configured.
Options are not yet supported.
+ lpuart,<addr>
+ lpuart32,<addr>
+ Use early console provided by Freescale LP UART driver
+ found on Freescale Vybrid and QorIQ LS1021A processors.
+ A valid base address must be provided, and the serial
+ port must already be setup and configured.
+
earlyprintk= [X86,SH,BLACKFIN,ARM,M68k]
earlyprintk=vga
earlyprintk=efi
diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index 0667d1a..1aec440 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -1539,6 +1539,7 @@
tristate "Freescale lpuart serial port support"
depends on HAS_DMA
select SERIAL_CORE
+ select SERIAL_EARLYCON
help
Support for the on-chip lpuart on some Freescale SOCs.
diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index 08ce76f..3d79003 100644
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -1746,6 +1746,45 @@
.data = &lpuart_reg,
};
+static void lpuart_early_write(struct console *con, const char *s, unsigned n)
+{
+ struct earlycon_device *dev = con->data;
+
+ uart_console_write(&dev->port, s, n, lpuart_console_putchar);
+}
+
+static void lpuart32_early_write(struct console *con, const char *s, unsigned n)
+{
+ struct earlycon_device *dev = con->data;
+
+ uart_console_write(&dev->port, s, n, lpuart32_console_putchar);
+}
+
+static int __init lpuart_early_console_setup(struct earlycon_device *device,
+ const char *opt)
+{
+ if (!device->port.membase)
+ return -ENODEV;
+
+ device->con->write = lpuart_early_write;
+ return 0;
+}
+
+static int __init lpuart32_early_console_setup(struct earlycon_device *device,
+ const char *opt)
+{
+ if (!device->port.membase)
+ return -ENODEV;
+
+ device->con->write = lpuart32_early_write;
+ return 0;
+}
+
+OF_EARLYCON_DECLARE(lpuart, "fsl,vf610-lpuart", lpuart_early_console_setup);
+OF_EARLYCON_DECLARE(lpuart32, "fsl,ls1021a-lpuart", lpuart32_early_console_setup);
+EARLYCON_DECLARE(lpuart, lpuart_early_console_setup);
+EARLYCON_DECLARE(lpuart32, lpuart32_early_console_setup);
+
#define LPUART_CONSOLE (&lpuart_console)
#define LPUART32_CONSOLE (&lpuart32_console)
#else