serial: earlycon: add DT support
This adds the infrastructure to generic earlycon for earlycon setup
using DT. The actual setup is not enabled until a following commit to
add the FDT parsing.
Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Grant Likely <grant.likely@linaro.org>
diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
index c92e830..5131b5e 100644
--- a/drivers/tty/serial/earlycon.c
+++ b/drivers/tty/serial/earlycon.c
@@ -15,6 +15,8 @@
#include <linux/init.h>
#include <linux/io.h>
#include <linux/serial_core.h>
+#include <linux/sizes.h>
+#include <linux/mod_devicetable.h>
#ifdef CONFIG_FIX_EARLYCON_MEM
#include <asm/fixmap.h>
@@ -32,6 +34,9 @@
.con = &early_con,
};
+static const struct of_device_id __earlycon_of_table_sentinel
+ __used __section(__earlycon_of_table_end);
+
static void __iomem * __init earlycon_map(unsigned long paddr, size_t size)
{
void __iomem *base;
@@ -142,3 +147,26 @@
register_console(early_console_dev.con);
return 0;
}
+
+int __init of_setup_earlycon(unsigned long addr,
+ int (*setup)(struct earlycon_device *, const char *))
+{
+ int err;
+ struct uart_port *port = &early_console_dev.port;
+
+ port->iotype = UPIO_MEM;
+ port->mapbase = addr;
+ port->uartclk = BASE_BAUD * 16;
+ port->membase = earlycon_map(addr, SZ_4K);
+
+ early_console_dev.con->data = &early_console_dev;
+ err = setup(&early_console_dev, NULL);
+ if (err < 0)
+ return err;
+ if (!early_console_dev.con->write)
+ return -ENODEV;
+
+
+ register_console(early_console_dev.con);
+ return 0;
+}