From 18a8bd949d6adb311ea816125ff65050df1f3f6e Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Sun, 15 Jul 2007 23:37:59 -0700 Subject: serial: convert early_uart to earlycon for 8250 Beacuse SERIAL_PORT_DFNS is removed from include/asm-i386/serial.h and include/asm-x86_64/serial.h. the serial8250_ports need to be probed late in serial initializing stage. the console_init=>serial8250_console_init=> register_console=>serial8250_console_setup will return -ENDEV, and console ttyS0 can not be enabled at that time. need to wait till uart_add_one_port in drivers/serial/serial_core.c to call register_console to get console ttyS0. that is too late. Make early_uart to use early_param, so uart console can be used earlier. Make it to be bootconsole with CON_BOOT flag, so can use console handover feature. and it will switch to corresponding normal serial console automatically. new command line will be: console=uart8250,io,0x3f8,9600n8 console=uart8250,mmio,0xff5e0000,115200n8 or earlycon=uart8250,io,0x3f8,9600n8 earlycon=uart8250,mmio,0xff5e0000,115200n8 it will print in very early stage: Early serial console at I/O port 0x3f8 (options '9600n8') console [uart0] enabled later for console it will print: console handover: boot [uart0] -> real [ttyS0] Signed-off-by: Cc: Andi Kleen Cc: Bjorn Helgaas Cc: Russell King Cc: Gerd Hoffmann Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/firmware/pcdp.c | 6 ++- drivers/serial/8250.c | 28 +++-------- drivers/serial/8250_early.c | 117 ++++++++++++++++++++++---------------------- drivers/serial/Kconfig | 14 ++++++ 4 files changed, 84 insertions(+), 81 deletions(-) (limited to 'drivers') diff --git a/drivers/firmware/pcdp.c b/drivers/firmware/pcdp.c index 2b4b76e8bd7..58e9f8e457f 100644 --- a/drivers/firmware/pcdp.c +++ b/drivers/firmware/pcdp.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include "pcdp.h" @@ -27,7 +28,7 @@ setup_serial_console(struct pcdp_uart *uart) char parity; mmio = (uart->addr.space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY); - p += sprintf(p, "console=uart,%s,0x%lx", + p += sprintf(p, "uart8250,%s,0x%lx", mmio ? "mmio" : "io", uart->addr.address); if (uart->baud) { p += sprintf(p, ",%lu", uart->baud); @@ -41,7 +42,8 @@ setup_serial_console(struct pcdp_uart *uart) } } - return early_serial_console_init(options); + add_preferred_console("uart", 8250, &options[9]); + return setup_early_serial8250_console(options); #else return -ENODEV; #endif diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c index c84dab083a8..0b3ec38ae61 100644 --- a/drivers/serial/8250.c +++ b/drivers/serial/8250.c @@ -2514,12 +2514,18 @@ static int __init serial8250_console_setup(struct console *co, char *options) return uart_set_options(port, co, baud, parity, bits, flow); } +static int __init serial8250_console_early_setup(void) +{ + return serial8250_find_port_for_earlycon(); +} + static struct uart_driver serial8250_reg; static struct console serial8250_console = { .name = "ttyS", .write = serial8250_console_write, .device = uart_console_device, .setup = serial8250_console_setup, + .early_setup = serial8250_console_early_setup, .flags = CON_PRINTBUFFER, .index = -1, .data = &serial8250_reg, @@ -2533,7 +2539,7 @@ static int __init serial8250_console_init(void) } console_initcall(serial8250_console_init); -static int __init find_port(struct uart_port *p) +int serial8250_find_port(struct uart_port *p) { int line; struct uart_port *port; @@ -2546,26 +2552,6 @@ static int __init find_port(struct uart_port *p) return -ENODEV; } -int __init serial8250_start_console(struct uart_port *port, char *options) -{ - int line; - - line = find_port(port); - if (line < 0) - return -ENODEV; - - add_preferred_console("ttyS", line, options); - printk("Adding console on ttyS%d at %s 0x%lx (options '%s')\n", - line, port->iotype == UPIO_MEM ? "MMIO" : "I/O port", - port->iotype == UPIO_MEM ? (unsigned long) port->mapbase : - (unsigned long) port->iobase, options); - if (!(serial8250_console.flags & CON_ENABLED)) { - serial8250_console.flags &= ~CON_PRINTBUFFER; - register_console(&serial8250_console); - } - return line; -} - #define SERIAL8250_CONSOLE &serial8250_console #else #define SERIAL8250_CONSOLE NULL diff --git a/drivers/serial/8250_early.c b/drivers/serial/8250_early.c index 7e511199b4c..947c20507e1 100644 --- a/drivers/serial/8250_early.c +++ b/drivers/serial/8250_early.c @@ -17,13 +17,11 @@ * we locate the device directly by its MMIO or I/O port address. * * The user can specify the device directly, e.g., - * console=uart,io,0x3f8,9600n8 - * console=uart,mmio,0xff5e0000,115200n8 - * or platform code can call early_uart_console_init() to set - * the early UART device. - * - * After the normal serial driver starts, we try to locate the - * matching ttyS device and start a console there. + * earlycon=uart8250,io,0x3f8,9600n8 + * earlycon=uart8250,mmio,0xff5e0000,115200n8 + * or + * console=uart8250,io,0x3f8,9600n8 + * console=uart8250,mmio,0xff5e0000,115200n8 */ #include @@ -32,17 +30,21 @@ #include #include #include +#include #include #include +#ifdef CONFIG_FIX_EARLYCON_MEM +#include +#include +#endif -struct early_uart_device { +struct early_serial8250_device { struct uart_port port; char options[16]; /* e.g., 115200n8 */ unsigned int baud; }; -static struct early_uart_device early_device __initdata; -static int early_uart_registered __initdata; +static struct early_serial8250_device early_device; static unsigned int __init serial_in(struct uart_port *port, int offset) { @@ -80,7 +82,7 @@ static void __init putc(struct uart_port *port, int c) serial_out(port, UART_TX, c); } -static void __init early_uart_write(struct console *console, const char *s, unsigned int count) +static void __init early_serial8250_write(struct console *console, const char *s, unsigned int count) { struct uart_port *port = &early_device.port; unsigned int ier; @@ -111,7 +113,7 @@ static unsigned int __init probe_baud(struct uart_port *port) return (port->uartclk / 16) / quot; } -static void __init init_port(struct early_uart_device *device) +static void __init init_port(struct early_serial8250_device *device) { struct uart_port *port = &device->port; unsigned int divisor; @@ -130,10 +132,9 @@ static void __init init_port(struct early_uart_device *device) serial_out(port, UART_LCR, c & ~UART_LCR_DLAB); } -static int __init parse_options(struct early_uart_device *device, char *options) +static int __init parse_options(struct early_serial8250_device *device, char *options) { struct uart_port *port = &device->port; - int mapsize = 64; int mmio, length; if (!options) @@ -143,12 +144,18 @@ static int __init parse_options(struct early_uart_device *device, char *options) if (!strncmp(options, "mmio,", 5)) { port->iotype = UPIO_MEM; port->mapbase = simple_strtoul(options + 5, &options, 0); - port->membase = ioremap(port->mapbase, mapsize); +#ifdef CONFIG_FIX_EARLYCON_MEM + set_fixmap_nocache(FIX_EARLYCON_MEM_BASE, port->mapbase & PAGE_MASK); + port->membase = (void __iomem *)__fix_to_virt(FIX_EARLYCON_MEM_BASE); + port->membase += port->mapbase & ~PAGE_MASK; +#else + port->membase = ioremap(port->mapbase, 64); if (!port->membase) { printk(KERN_ERR "%s: Couldn't ioremap 0x%lx\n", __FUNCTION__, port->mapbase); return -ENOMEM; } +#endif mmio = 1; } else if (!strncmp(options, "io,", 3)) { port->iotype = UPIO_PORT; @@ -175,9 +182,16 @@ static int __init parse_options(struct early_uart_device *device, char *options) return 0; } -static int __init early_uart_setup(struct console *console, char *options) +static struct console early_serial8250_console __initdata = { + .name = "uart", + .write = early_serial8250_write, + .flags = CON_PRINTBUFFER | CON_BOOT, + .index = -1, +}; + +static int __init early_serial8250_setup(char *options) { - struct early_uart_device *device = &early_device; + struct early_serial8250_device *device = &early_device; int err; if (device->port.membase || device->port.iobase) @@ -190,61 +204,48 @@ static int __init early_uart_setup(struct console *console, char *options) return 0; } -static struct console early_uart_console __initdata = { - .name = "uart", - .write = early_uart_write, - .setup = early_uart_setup, - .flags = CON_PRINTBUFFER, - .index = -1, -}; - -static int __init early_uart_console_init(void) -{ - if (!early_uart_registered) { - register_console(&early_uart_console); - early_uart_registered = 1; - } - return 0; -} -console_initcall(early_uart_console_init); - -int __init early_serial_console_init(char *cmdline) +int __init setup_early_serial8250_console(char *cmdline) { char *options; int err; - options = strstr(cmdline, "console=uart,"); - if (!options) - return -ENODEV; + options = strstr(cmdline, "uart8250,"); + if (!options) { + options = strstr(cmdline, "uart,"); + if (!options) + return 0; + } options = strchr(cmdline, ',') + 1; - if ((err = early_uart_setup(NULL, options)) < 0) + if ((err = early_serial8250_setup(options)) < 0) return err; - return early_uart_console_init(); + + register_console(&early_serial8250_console); + + return 0; } -static int __init early_uart_console_switch(void) +int __init serial8250_find_port_for_earlycon(void) { - struct early_uart_device *device = &early_device; + struct early_serial8250_device *device = &early_device; struct uart_port *port = &device->port; - int mmio, line; + int line; + int ret; - if (!(early_uart_console.flags & CON_ENABLED)) - return 0; + if (!device->port.membase && !device->port.iobase) + return -ENODEV; - /* Try to start the normal driver on a matching line. */ - mmio = (port->iotype == UPIO_MEM); - line = serial8250_start_console(port, device->options); + line = serial8250_find_port(port); if (line < 0) - printk("No ttyS device at %s 0x%lx for console\n", - mmio ? "MMIO" : "I/O port", - mmio ? port->mapbase : - (unsigned long) port->iobase); + return -ENODEV; - unregister_console(&early_uart_console); - if (mmio) - iounmap(port->membase); + ret = update_console_cmdline("uart", 8250, + "ttyS", line, device->options); + if (ret < 0) + ret = update_console_cmdline("uart", 0, + "ttyS", line, device->options); - return 0; + return ret; } -late_initcall(early_uart_console_switch); + +early_param("earlycon", setup_early_serial8250_console); diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig index 2adbed4e10f..cab42cbd920 100644 --- a/drivers/serial/Kconfig +++ b/drivers/serial/Kconfig @@ -62,8 +62,22 @@ config SERIAL_8250_CONSOLE kernel will automatically use the first serial line, /dev/ttyS0, as system console. + you can set that using a kernel command line option such as + "console=uart8250,io,0x3f8,9600n8" + "console=uart8250,mmio,0xff5e0000,115200n8". + and it will switch to normal serial console when correponding port is + ready. + "earlycon=uart8250,io,0x3f8,9600n8" + "earlycon=uart8250,mmio,0xff5e0000,115200n8". + it will not only setup early console. + If unsure, say N. +config FIX_EARLYCON_MEM + bool + depends on X86 + default y + config SERIAL_8250_GSC tristate depends on SERIAL_8250 && GSC -- cgit v1.2.3