From ada64e4c98eb5f04a9ca223c5ff9e7ac22ce6404 Mon Sep 17 00:00:00 2001 From: Jason Wessel Date: Thu, 20 May 2010 21:04:24 -0500 Subject: kgdboc,keyboard: Keyboard driver for kdb with kgdb This patch adds in the kdb PS/2 keyboard driver. This was mostly a direct port from the original kdb where I cleaned up the code against checkpatch.pl and added the glue to stitch it into kgdb. This patch also enables early kdb debug via kgdbwait and the keyboard. All the access to configure kdb using either a serial console or the keyboard is done via kgdboc. If you want to use only the keyboard and want to break in early you would add to your kernel command arguments: kgdboc=kbd kgdbwait If you wanted serial and or the keyboard access you could use: kgdboc=kbd,ttyS0 You can also configure kgdboc as a kernel module or at run time with the sysfs where you can activate and deactivate kgdb. Turn it on: echo kbd,ttyS0 > /sys/module/kgdboc/parameters/kgdboc Turn it off: echo "" > /sys/module/kgdboc/parameters/kgdboc Signed-off-by: Jason Wessel Reviewed-by: Dmitry Torokhov --- drivers/serial/kgdboc.c | 61 +++++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 54 insertions(+), 7 deletions(-) (limited to 'drivers/serial/kgdboc.c') diff --git a/drivers/serial/kgdboc.c b/drivers/serial/kgdboc.c index eadc1ab..ecef6e1 100644 --- a/drivers/serial/kgdboc.c +++ b/drivers/serial/kgdboc.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #define MAX_CONFIG_LEN 40 @@ -32,6 +33,40 @@ static struct kparam_string kps = { static struct tty_driver *kgdb_tty_driver; static int kgdb_tty_line; +#ifdef CONFIG_KDB_KEYBOARD +static int kgdboc_register_kbd(char **cptr) +{ + if (strncmp(*cptr, "kbd", 3) == 0) { + if (kdb_poll_idx < KDB_POLL_FUNC_MAX) { + kdb_poll_funcs[kdb_poll_idx] = kdb_get_kbd_char; + kdb_poll_idx++; + if (cptr[0][3] == ',') + *cptr += 4; + else + return 1; + } + } + return 0; +} + +static void kgdboc_unregister_kbd(void) +{ + int i; + + for (i = 0; i < kdb_poll_idx; i++) { + if (kdb_poll_funcs[i] == kdb_get_kbd_char) { + kdb_poll_idx--; + kdb_poll_funcs[i] = kdb_poll_funcs[kdb_poll_idx]; + kdb_poll_funcs[kdb_poll_idx] = NULL; + i--; + } + } +} +#else /* ! CONFIG_KDB_KEYBOARD */ +#define kgdboc_register_kbd(x) 0 +#define kgdboc_unregister_kbd() +#endif /* ! CONFIG_KDB_KEYBOARD */ + static int kgdboc_option_setup(char *opt) { if (strlen(opt) > MAX_CONFIG_LEN) { @@ -45,25 +80,38 @@ static int kgdboc_option_setup(char *opt) __setup("kgdboc=", kgdboc_option_setup); +static void cleanup_kgdboc(void) +{ + kgdboc_unregister_kbd(); + if (configured == 1) + kgdb_unregister_io_module(&kgdboc_io_ops); +} + static int configure_kgdboc(void) { struct tty_driver *p; int tty_line = 0; int err; + char *cptr = config; err = kgdboc_option_setup(config); if (err || !strlen(config) || isspace(config[0])) goto noconfig; err = -ENODEV; + kgdb_tty_driver = NULL; + + if (kgdboc_register_kbd(&cptr)) + goto do_register; - p = tty_find_polling_driver(config, &tty_line); + p = tty_find_polling_driver(cptr, &tty_line); if (!p) goto noconfig; kgdb_tty_driver = p; kgdb_tty_line = tty_line; +do_register: err = kgdb_register_io_module(&kgdboc_io_ops); if (err) goto noconfig; @@ -75,6 +123,7 @@ static int configure_kgdboc(void) noconfig: config[0] = 0; configured = 0; + cleanup_kgdboc(); return err; } @@ -88,20 +137,18 @@ static int __init init_kgdboc(void) return configure_kgdboc(); } -static void cleanup_kgdboc(void) -{ - if (configured == 1) - kgdb_unregister_io_module(&kgdboc_io_ops); -} - static int kgdboc_get_char(void) { + if (!kgdb_tty_driver) + return -1; return kgdb_tty_driver->ops->poll_get_char(kgdb_tty_driver, kgdb_tty_line); } static void kgdboc_put_char(u8 chr) { + if (!kgdb_tty_driver) + return; kgdb_tty_driver->ops->poll_put_char(kgdb_tty_driver, kgdb_tty_line, chr); } -- cgit v1.1 From efe2f29e324fd20e0449bcd6dc6dbe4734c2ba94 Mon Sep 17 00:00:00 2001 From: Jason Wessel Date: Thu, 20 May 2010 21:04:26 -0500 Subject: kgdboc,kdb: Allow kdb to work on a non open console port If kdb is open on a serial port that is not actually a console make sure to call the poll routines to emit and receive characters. Signed-off-by: Jason Wessel Acked-by: Martin Hicks --- drivers/serial/kgdboc.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'drivers/serial/kgdboc.c') diff --git a/drivers/serial/kgdboc.c b/drivers/serial/kgdboc.c index ecef6e1..b765ab4 100644 --- a/drivers/serial/kgdboc.c +++ b/drivers/serial/kgdboc.c @@ -16,6 +16,7 @@ #include #include #include +#include #define MAX_CONFIG_LEN 40 @@ -93,12 +94,14 @@ static int configure_kgdboc(void) int tty_line = 0; int err; char *cptr = config; + struct console *cons; err = kgdboc_option_setup(config); if (err || !strlen(config) || isspace(config[0])) goto noconfig; err = -ENODEV; + kgdboc_io_ops.is_console = 0; kgdb_tty_driver = NULL; if (kgdboc_register_kbd(&cptr)) @@ -108,6 +111,17 @@ static int configure_kgdboc(void) if (!p) goto noconfig; + cons = console_drivers; + while (cons) { + int idx; + if (cons->device && cons->device(cons, &idx) == p && + idx == tty_line) { + kgdboc_io_ops.is_console = 1; + break; + } + cons = cons->next; + } + kgdb_tty_driver = p; kgdb_tty_line = tty_line; -- cgit v1.1 From 9731191f75a54c4fa17e9b9b88f3144cf4b47836 Mon Sep 17 00:00:00 2001 From: Jason Wessel Date: Thu, 20 May 2010 21:04:30 -0500 Subject: kgdboc: Add ekgdboc for early use of the kernel debugger The ekgdboc= differs from kgdboc= in that you can begin debuggin as soon as the exceptions are setup and the kgdb I/O driver is available, instead of waiting until the tty subsystem is available. CC: kgdb-bugreport@lists.sourceforge.net Signed-off-by: Jason Wessel --- drivers/serial/kgdboc.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) (limited to 'drivers/serial/kgdboc.c') diff --git a/drivers/serial/kgdboc.c b/drivers/serial/kgdboc.c index b765ab4..a9a94ae 100644 --- a/drivers/serial/kgdboc.c +++ b/drivers/serial/kgdboc.c @@ -223,6 +223,25 @@ static struct kgdb_io kgdboc_io_ops = { .post_exception = kgdboc_post_exp_handler, }; +#ifdef CONFIG_KGDB_SERIAL_CONSOLE +/* This is only available if kgdboc is a built in for early debugging */ +int __init kgdboc_early_init(char *opt) +{ + /* save the first character of the config string because the + * init routine can destroy it. + */ + char save_ch; + + kgdboc_option_setup(opt); + save_ch = config[0]; + init_kgdboc(); + config[0] = save_ch; + return 0; +} + +early_param("ekgdboc", kgdboc_early_init); +#endif /* CONFIG_KGDB_SERIAL_CONSOLE */ + module_init(init_kgdboc); module_exit(cleanup_kgdboc); module_param_call(kgdboc, param_set_kgdboc_var, param_get_string, &kps, 0644); -- cgit v1.1