Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759224AbXESCCR (ORCPT ); Fri, 18 May 2007 22:02:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753278AbXESCCG (ORCPT ); Fri, 18 May 2007 22:02:06 -0400 Received: from nwk-ea-fw-1.sun.com ([192.18.42.249]:26498 "EHLO nwk-ea-fw-1.sun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753049AbXESCCF (ORCPT ); Fri, 18 May 2007 22:02:05 -0400 Date: Fri, 18 May 2007 19:00:16 -0700 From: Yinghai Lu Subject: [PATCH]serial: make early_uart to use early_prarm instead of console_initcall To: Bjorn Helgaas , Gerd Hoffmann , Andi Kleen , akpm@linux-foundation.org, Linus Torvalds Cc: linux kernel mailing list Reply-to: Yinghai Lu Message-id: <200705181900.17101.yinghai.lu@sun.com> MIME-version: 1.0 Content-type: text/plain; charset=us-ascii Content-transfer-encoding: 7BIT Content-disposition: inline User-Agent: KMail/1.8.2 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 10406 Lines: 334 [PATCH]serial: make early_uart to use early_prarm instead of console_initcall 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 earlycon=uart,io,0x3f8,9600n8 earlycon=uart,io,0x3f8,9600n8 console=tty0 it will print in very early stage Early serial console at I/O port 0x3f8 (options '9600n8') later for console it will print console handover: boot [uart0] -> real [ttyS0] Signed-off-by: diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c index c84dab0..75459e8 100644 --- a/drivers/serial/8250.c +++ b/drivers/serial/8250.c @@ -2367,6 +2367,7 @@ static struct uart_ops serial8250_pops = { .request_port = serial8250_request_port, .config_port = serial8250_config_port, .verify_port = serial8250_verify_port, + .find_port_for_earlycon = serial8250_find_port_for_earlycon, }; static struct uart_8250_port serial8250_ports[UART_NR]; @@ -2533,7 +2534,7 @@ static int __init serial8250_console_init(void) } console_initcall(serial8250_console_init); -static int __init find_port(struct uart_port *p) +int __init find_port_serial8250(struct uart_port *p) { int line; struct uart_port *port; @@ -2546,26 +2547,6 @@ 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 7e51119..42d4abe 100644 --- a/drivers/serial/8250_early.c +++ b/drivers/serial/8250_early.c @@ -17,13 +17,9 @@ * 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. + * earlycon=uart,io,0x3f8,9600n8 + * earlycon=uart,mmio,0xff5e0000,115200n8 * - * After the normal serial driver starts, we try to locate the - * matching ttyS device and start a console there. */ #include @@ -32,6 +28,7 @@ #include #include #include +#include #include #include @@ -42,7 +39,6 @@ struct early_uart_device { }; static struct early_uart_device early_device __initdata; -static int early_uart_registered __initdata; static unsigned int __init serial_in(struct uart_port *port, int offset) { @@ -175,6 +171,13 @@ static int __init parse_options(struct early_uart_device *device, char *options) return 0; } +static struct console early_uart_console __initdata = { + .name = "uart", + .write = early_uart_write, + .flags = CON_PRINTBUFFER, + .index = -1, +}; + static int __init early_uart_setup(struct console *console, char *options) { struct early_uart_device *device = &early_device; @@ -190,61 +193,60 @@ 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) +static int __init setup_early_serial_console(char *cmdline) { char *options; int err; - options = strstr(cmdline, "console=uart,"); + options = strstr(cmdline, "uart,"); if (!options) return -ENODEV; options = strchr(cmdline, ',') + 1; if ((err = early_uart_setup(NULL, options)) < 0) return err; - return early_uart_console_init(); + + early_uart_console.flags |= CON_BOOT; + register_console(&early_uart_console); + + /* add one dummy entry in console_cmdline*/ + add_preferred_console("ttyS", 255, early_device.options); + + return 0; } -static int __init early_uart_console_switch(void) +int serial8250_find_port_for_earlycon(void) { struct early_uart_device *device = &early_device; struct uart_port *port = &device->port; - int mmio, line; + int line; - if (!(early_uart_console.flags & CON_ENABLED)) - return 0; + line = find_port_serial8250(port); - /* Try to start the normal driver on a matching line. */ - mmio = (port->iotype == UPIO_MEM); - line = serial8250_start_console(port, device->options); 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; + + /* update the dummy entry to what we want console type */ + update_console_cmdline_console_index("ttyS", 255, line); + + return 0; + +} + +early_param("earlycon", setup_early_serial_console); - unregister_console(&early_uart_console); - if (mmio) +static int __init early_uart_console_post(void) +{ + struct early_uart_device *device = &early_device; + struct uart_port *port = &device->port; + + if (!(early_uart_console.flags & CON_ENABLED)) + return 0; + + if (port->iotype == UPIO_MEM) iounmap(port->membase); return 0; } -late_initcall(early_uart_console_switch); + +late_initcall(early_uart_console_post); diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig index 315ea99..fc58473 100644 --- a/drivers/serial/Kconfig +++ b/drivers/serial/Kconfig @@ -62,6 +62,12 @@ 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 + "earlycon=uart,io,0x3f8,9600n8" or + "earlycon=uart,mem,0xfe000008,115200n8". + and it will switch to normal serial console when correponding port is + ready. + If unsure, say N. config SERIAL_8250_GSC diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c index 326020f..956d435 100644 --- a/drivers/serial/serial_core.c +++ b/drivers/serial/serial_core.c @@ -2303,8 +2303,11 @@ int uart_add_one_port(struct uart_driver *drv, struct uart_port *port) * It may be that the port was not available. */ if (port->type != PORT_UNKNOWN && - port->cons && !(port->cons->flags & CON_ENABLED)) + port->cons && !(port->cons->flags & CON_ENABLED)) { + if(port->ops && port->ops->find_port_for_earlycon) + port->ops->find_port_for_earlycon(); register_console(port->cons); + } /* * Ensure UPF_DEAD is not set. diff --git a/include/linux/console.h b/include/linux/console.h index 62ef6e1..4cb7749 100644 --- a/include/linux/console.h +++ b/include/linux/console.h @@ -107,6 +107,7 @@ struct console { }; extern int add_preferred_console(char *name, int idx, char *options); +extern int update_console_cmdline_console_index(char *name, int idx_old, int idx_new); extern void register_console(struct console *); extern int unregister_console(struct console *); extern struct console *console_drivers; diff --git a/include/linux/serial.h b/include/linux/serial.h index 33fc8cb..deb7143 100644 --- a/include/linux/serial.h +++ b/include/linux/serial.h @@ -177,11 +177,5 @@ struct serial_icounter_struct { #ifdef __KERNEL__ #include -/* Allow architectures to override entries in serial8250_ports[] at run time: */ -struct uart_port; /* forward declaration */ -extern int early_serial_setup(struct uart_port *port); -extern int early_serial_console_init(char *options); -extern int serial8250_start_console(struct uart_port *port, char *options); - #endif /* __KERNEL__ */ #endif /* _LINUX_SERIAL_H */ diff --git a/include/linux/serial_8250.h b/include/linux/serial_8250.h index 71310d8..0d79fc5 100644 --- a/include/linux/serial_8250.h +++ b/include/linux/serial_8250.h @@ -60,4 +60,7 @@ void serial8250_unregister_port(int line); void serial8250_suspend_port(int line); void serial8250_resume_port(int line); +extern int find_port_serial8250(struct uart_port *p); +extern int serial8250_find_port_for_earlycon(void); + #endif diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index a3ac4c8..b74fa4a 100644 --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -199,6 +199,11 @@ struct uart_ops { void (*config_port)(struct uart_port *, int); int (*verify_port)(struct uart_port *, struct serial_struct *); int (*ioctl)(struct uart_port *, unsigned int, unsigned long); + + /* + * for earlycon to console switch + */ + int (*find_port_for_earlycon)(void); }; #define UART_CONFIG_TYPE (1 << 0) diff --git a/init/main.c b/init/main.c diff --git a/kernel/printk.c b/kernel/printk.c index 0bbdeac..253c0f7 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -726,6 +726,21 @@ int __init add_preferred_console(char *name, int idx, char *options) return 0; } +int __init update_console_cmdline_console_index(char *name, int idx_old, int idx_new) +{ + int i; + + for(i = 0; i < MAX_CMDLINECONSOLES && console_cmdline[i].name[0]; i++) + if (strcmp(console_cmdline[i].name, name) == 0 && + console_cmdline[i].index == idx_old) { + console_cmdline[i].index = idx_new; + return 0; + } + + return 0; +} + + #ifndef CONFIG_DISABLE_CONSOLE_SUSPEND /** * suspend_console - suspend the console subsystem - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/