diff options
| -rw-r--r-- | Documentation/kernel-parameters.txt | 12 | ||||
| -rw-r--r-- | drivers/tty/serial/Kconfig | 1 | ||||
| -rw-r--r-- | drivers/tty/serial/samsung.c | 103 |
3 files changed, 116 insertions, 0 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 4df73da11adc..e855697f54c5 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -970,6 +970,18 @@ bytes respectively. Such letter suffixes can also be entirely omitted. smh Use ARM semihosting calls for early console. + s3c2410,<addr> + s3c2412,<addr> + s3c2440,<addr> + s3c6400,<addr> + s5pv210,<addr> + exynos4210,<addr> + Use early console provided by serial driver available + on Samsung SoCs, requires selecting proper type and + a correct base address of the selected UART port. The + serial port must already be setup and configured. + Options are not yet supported. + earlyprintk= [X86,SH,BLACKFIN,ARM,M68k] earlyprintk=vga earlyprintk=efi diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig index 35677f75a1d8..c63317e87c33 100644 --- a/drivers/tty/serial/Kconfig +++ b/drivers/tty/serial/Kconfig @@ -241,6 +241,7 @@ config SERIAL_SAMSUNG tristate "Samsung SoC serial support" depends on PLAT_SAMSUNG || ARCH_EXYNOS select SERIAL_CORE + select SERIAL_EARLYCON help Support for the on-chip UARTs on the Samsung S3C24XX series CPUs, providing /dev/ttySAC0, 1 and 2 (note, some machines may not diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c index 024e5ecee985..a6bef8dcdc3c 100644 --- a/drivers/tty/serial/samsung.c +++ b/drivers/tty/serial/samsung.c @@ -2403,6 +2403,109 @@ static struct platform_driver samsung_serial_driver = { module_platform_driver(samsung_serial_driver); +/* + * Early console. + */ + +struct samsung_early_console_data { + u32 txfull_mask; +}; + +static void samsung_early_busyuart(struct uart_port *port) +{ + while (!(readl(port->membase + S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXFE)) + ; +} + +static void samsung_early_busyuart_fifo(struct uart_port *port) +{ + struct samsung_early_console_data *data = port->private_data; + + while (readl(port->membase + S3C2410_UFSTAT) & data->txfull_mask) + ; +} + +static void samsung_early_putc(struct uart_port *port, int c) +{ + if (readl(port->membase + S3C2410_UFCON) & S3C2410_UFCON_FIFOMODE) + samsung_early_busyuart_fifo(port); + else + samsung_early_busyuart(port); + + writeb(c, port->membase + S3C2410_UTXH); +} + +static void samsung_early_write(struct console *con, const char *s, unsigned n) +{ + struct earlycon_device *dev = con->data; + + uart_console_write(&dev->port, s, n, samsung_early_putc); +} + +static int __init samsung_early_console_setup(struct earlycon_device *device, + const char *opt) +{ + if (!device->port.membase) + return -ENODEV; + + device->con->write = samsung_early_write; + return 0; +} + +/* S3C2410 */ +static struct samsung_early_console_data s3c2410_early_console_data = { + .txfull_mask = S3C2410_UFSTAT_TXFULL, +}; + +static int __init s3c2410_early_console_setup(struct earlycon_device *device, + const char *opt) +{ + device->port.private_data = &s3c2410_early_console_data; + return samsung_early_console_setup(device, opt); +} +OF_EARLYCON_DECLARE(s3c2410, "samsung,s3c2410-uart", + s3c2410_early_console_setup); +EARLYCON_DECLARE(s3c2410, s3c2410_early_console_setup); + +/* S3C2412, S3C2440, S3C64xx */ +static struct samsung_early_console_data s3c2440_early_console_data = { + .txfull_mask = S3C2440_UFSTAT_TXFULL, +}; + +static int __init s3c2440_early_console_setup(struct earlycon_device *device, + const char *opt) +{ + device->port.private_data = &s3c2440_early_console_data; + return samsung_early_console_setup(device, opt); +} +OF_EARLYCON_DECLARE(s3c2412, "samsung,s3c2412-uart", + s3c2440_early_console_setup); +OF_EARLYCON_DECLARE(s3c2440, "samsung,s3c2440-uart", + s3c2440_early_console_setup); +OF_EARLYCON_DECLARE(s3c6400, "samsung,s3c6400-uart", + s3c2440_early_console_setup); +EARLYCON_DECLARE(s3c2412, s3c2440_early_console_setup); +EARLYCON_DECLARE(s3c2440, s3c2440_early_console_setup); +EARLYCON_DECLARE(s3c6400, s3c2440_early_console_setup); + +/* S5PV210, EXYNOS */ +static struct samsung_early_console_data s5pv210_early_console_data = { + .txfull_mask = S5PV210_UFSTAT_TXFULL, +}; + +static int __init s5pv210_early_console_setup(struct earlycon_device *device, + const char *opt) +{ + device->port.private_data = &s5pv210_early_console_data; + return samsung_early_console_setup(device, opt); +} +OF_EARLYCON_DECLARE(s5pv210, "samsung,s5pv210-uart", + s5pv210_early_console_setup); +OF_EARLYCON_DECLARE(exynos4210, "samsung,exynos4210-uart", + s5pv210_early_console_setup); +EARLYCON_DECLARE(s5pv210, s5pv210_early_console_setup); +EARLYCON_DECLARE(exynos4210, s5pv210_early_console_setup); + MODULE_ALIAS("platform:samsung-uart"); MODULE_DESCRIPTION("Samsung SoC Serial port driver"); MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>"); |