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>
This commit is contained in:
Rob Herring 2014-03-27 08:06:16 -05:00
parent 54196ccbe0
commit b0b6abd34c
3 changed files with 37 additions and 1 deletions

View File

@ -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 @@ static struct earlycon_device early_console_dev = {
.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 @@ int __init setup_earlycon(char *buf, const char *match,
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;
}

View File

@ -155,6 +155,7 @@
#define CLK_OF_TABLES() OF_TABLE(CONFIG_COMMON_CLK, clk)
#define RESERVEDMEM_OF_TABLES() OF_TABLE(CONFIG_OF_RESERVED_MEM, reservedmem)
#define CPU_METHOD_OF_TABLES() OF_TABLE(CONFIG_SMP, cpu_method)
#define EARLYCON_OF_TABLES() OF_TABLE(CONFIG_SERIAL_EARLYCON, earlycon)
#define KERNEL_DTB() \
STRUCT_ALIGN(); \
@ -483,7 +484,8 @@
CLKSRC_OF_TABLES() \
CPU_METHOD_OF_TABLES() \
KERNEL_DTB() \
IRQCHIP_OF_MATCH_TABLE()
IRQCHIP_OF_MATCH_TABLE() \
EARLYCON_OF_TABLES()
#define INIT_TEXT \
*(.init.text) \

View File

@ -294,6 +294,9 @@ struct earlycon_device {
int setup_earlycon(char *buf, const char *match,
int (*setup)(struct earlycon_device *, const char *));
extern int of_setup_earlycon(unsigned long addr,
int (*setup)(struct earlycon_device *, const char *));
#define EARLYCON_DECLARE(name, func) \
static int __init name ## _setup_earlycon(char *buf) \
{ \
@ -301,6 +304,9 @@ static int __init name ## _setup_earlycon(char *buf) \
} \
early_param("earlycon", name ## _setup_earlycon);
#define OF_EARLYCON_DECLARE(name, compat, fn) \
_OF_DECLARE(earlycon, name, compat, fn, void *)
struct uart_port *uart_get_console(struct uart_port *ports, int nr,
struct console *c);
void uart_parse_options(char *options, int *baud, int *parity, int *bits,