diff options
| -rw-r--r-- | drivers/tty/serial/8250/8250_early.c | 7 | ||||
| -rw-r--r-- | drivers/tty/serial/earlycon.c | 92 | ||||
| -rw-r--r-- | include/asm-generic/vmlinux.lds.h | 9 | ||||
| -rw-r--r-- | include/linux/serial_core.h | 19 |
4 files changed, 94 insertions, 33 deletions
diff --git a/drivers/tty/serial/8250/8250_early.c b/drivers/tty/serial/8250/8250_early.c index b199c10689f4..d272139a5729 100644 --- a/drivers/tty/serial/8250/8250_early.c +++ b/drivers/tty/serial/8250/8250_early.c @@ -170,10 +170,5 @@ EARLYCON_DECLARE(uart, early_serial8250_setup); int __init setup_early_serial8250_console(char *cmdline) { - char match[] = "uart8250"; - - if (cmdline && cmdline[4] == ',') - match[4] = '\0'; - - return setup_earlycon(cmdline, match, early_serial8250_setup); + return setup_earlycon(cmdline); } diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c index 9fb76b66c545..5fdc9f3ecd64 100644 --- a/drivers/tty/serial/earlycon.c +++ b/drivers/tty/serial/earlycon.c @@ -10,6 +10,9 @@ * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + #include <linux/console.h> #include <linux/kernel.h> #include <linux/init.h> @@ -34,6 +37,10 @@ static struct earlycon_device early_console_dev = { .con = &early_con, }; +extern struct earlycon_id __earlycon_table[]; +static const struct earlycon_id __earlycon_table_sentinel + __used __section(__earlycon_table_end); + static const struct of_device_id __earlycon_of_table_sentinel __used __section(__earlycon_of_table_end); @@ -96,9 +103,7 @@ static int __init parse_options(struct earlycon_device *device, char *options) return 0; } - -static int __init -register_earlycon(char *buf, int (*setup)(struct earlycon_device *, const char *)) +static int __init register_earlycon(char *buf, const struct earlycon_id *match) { int err; struct uart_port *port = &early_console_dev.port; @@ -112,7 +117,7 @@ register_earlycon(char *buf, int (*setup)(struct earlycon_device *, const char * port->membase = earlycon_map(port->mapbase, 64); early_console_dev.con->data = &early_console_dev; - err = setup(&early_console_dev, buf); + err = match->setup(&early_console_dev, buf); if (err < 0) return err; if (!early_console_dev.con->write) @@ -122,27 +127,76 @@ register_earlycon(char *buf, int (*setup)(struct earlycon_device *, const char * return 0; } -int __init setup_earlycon(char *buf, const char *match, - int (*setup)(struct earlycon_device *, const char *)) +/** + * setup_earlycon - match and register earlycon console + * @buf: earlycon param string + * + * Registers the earlycon console matching the earlycon specified + * in the param string @buf. Acceptable param strings are of the form + * <name>,io|mmio|mmio32,<addr>,<options> + * <name>,0x<addr>,<options> + * <name>,<options> + * <name> + * + * Only for the third form does the earlycon setup() method receive the + * <options> string in the 'options' parameter; all other forms set + * the parameter to NULL. + * + * Returns 0 if an attempt to register the earlycon was made, + * otherwise negative error code + */ +int __init setup_earlycon(char *buf) { - size_t len; + const struct earlycon_id *match; - if (!buf || !match || !setup) - return 0; + if (!buf || !buf[0]) + return -EINVAL; - len = strlen(match); - if (strncmp(buf, match, len)) - return 0; + if (early_con.flags & CON_ENABLED) + return -EALREADY; - if (buf[len]) { - if (buf[len] != ',') - return 0; - buf += len + 1; - } else - buf = NULL; + for (match = __earlycon_table; match->name[0]; match++) { + size_t len = strlen(match->name); - return register_earlycon(buf, setup); + if (strncmp(buf, match->name, len)) + continue; + + if (buf[len]) { + if (buf[len] != ',') + continue; + buf += len + 1; + } else + buf = NULL; + + return register_earlycon(buf, match); + } + + return -ENOENT; +} + +/* early_param wrapper for setup_earlycon() */ +static int __init param_setup_earlycon(char *buf) +{ + int err; + + /* + * Just 'earlycon' is a valid param for devicetree earlycons; + * don't generate a warning from parse_early_params() in that case + */ + if (!buf || !buf[0]) + return 0; + + err = setup_earlycon(buf); + if (err == -ENOENT) { + pr_warn("no match for %s\n", buf); + err = 0; + } else if (err == -EALREADY) { + pr_warn("already registered\n"); + err = 0; + } + return err; } +early_param("earlycon", param_setup_earlycon); int __init of_setup_earlycon(unsigned long addr, int (*setup)(struct earlycon_device *, const char *)) diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index ac78910d7416..87e5b6f8f4fc 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -150,6 +150,14 @@ #define TRACE_SYSCALLS() #endif +#ifdef CONFIG_SERIAL_EARLYCON +#define EARLYCON_TABLE() . = ALIGN(8); \ + VMLINUX_SYMBOL(__earlycon_table) = .; \ + *(__earlycon_table) \ + *(__earlycon_table_end) +#else +#define EARLYCON_TABLE() +#endif #define ___OF_TABLE(cfg, name) _OF_TABLE_##cfg(name) #define __OF_TABLE(cfg, name) ___OF_TABLE(cfg, name) @@ -503,6 +511,7 @@ CPU_METHOD_OF_TABLES() \ KERNEL_DTB() \ IRQCHIP_OF_MATCH_TABLE() \ + EARLYCON_TABLE() \ EARLYCON_OF_TABLES() #define INIT_TEXT \ diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index 980170e5a982..8aeec4913a9c 100644 --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -337,18 +337,21 @@ struct earlycon_device { char options[16]; /* e.g., 115200n8 */ unsigned int baud; }; -int setup_earlycon(char *buf, const char *match, - int (*setup)(struct earlycon_device *, const char *)); +struct earlycon_id { + char name[16]; + int (*setup)(struct earlycon_device *, const char *options); +}; + +extern int setup_earlycon(char *buf); 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) \ -{ \ - return setup_earlycon(buf, __stringify(name), func); \ -} \ -early_param("earlycon", name ## _setup_earlycon); +#define EARLYCON_DECLARE(_name, func) \ + static const struct earlycon_id __earlycon_##_name \ + __used __section(__earlycon_table) \ + = { .name = __stringify(_name), \ + .setup = func } #define OF_EARLYCON_DECLARE(name, compat, fn) \ _OF_DECLARE(earlycon, name, compat, fn, void *) |