^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Based on the same principle as kgdboe using the NETPOLL api, this
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) * driver uses a console polling api to implement a gdb serial inteface
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * which is multiplexed on a console port.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * Maintainer: Jason Wessel <jason.wessel@windriver.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) * 2007-2008 (c) Jason Wessel - Wind River Systems, Inc.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/ctype.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include <linux/kgdb.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #include <linux/kdb.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) #include <linux/tty.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) #include <linux/console.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) #include <linux/vt_kern.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) #include <linux/input.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) #include <linux/platform_device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) #include <linux/serial_core.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) #define MAX_CONFIG_LEN 40
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) static struct kgdb_io kgdboc_io_ops;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) /* -1 = init not run yet, 0 = unconfigured, 1 = configured. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) static int configured = -1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) static DEFINE_MUTEX(config_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) static char config[MAX_CONFIG_LEN];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) static struct kparam_string kps = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) .string = config,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) .maxlen = MAX_CONFIG_LEN,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) static int kgdboc_use_kms; /* 1 if we use kernel mode switching */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) static struct tty_driver *kgdb_tty_driver;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) static int kgdb_tty_line;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) static struct platform_device *kgdboc_pdev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) #if IS_BUILTIN(CONFIG_KGDB_SERIAL_CONSOLE)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) static struct kgdb_io kgdboc_earlycon_io_ops;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) static int (*earlycon_orig_exit)(struct console *con);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) #endif /* IS_BUILTIN(CONFIG_KGDB_SERIAL_CONSOLE) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) #ifdef CONFIG_KDB_KEYBOARD
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) static int kgdboc_reset_connect(struct input_handler *handler,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) struct input_dev *dev,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) const struct input_device_id *id)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) input_reset_device(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) /* Return an error - we do not want to bind, just to reset */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) return -ENODEV;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) static void kgdboc_reset_disconnect(struct input_handle *handle)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) /* We do not expect anyone to actually bind to us */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) BUG();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) static const struct input_device_id kgdboc_reset_ids[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) .flags = INPUT_DEVICE_ID_MATCH_EVBIT,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) .evbit = { BIT_MASK(EV_KEY) },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) { }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) static struct input_handler kgdboc_reset_handler = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) .connect = kgdboc_reset_connect,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) .disconnect = kgdboc_reset_disconnect,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) .name = "kgdboc_reset",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) .id_table = kgdboc_reset_ids,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) static DEFINE_MUTEX(kgdboc_reset_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) static void kgdboc_restore_input_helper(struct work_struct *dummy)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) * We need to take a mutex to prevent several instances of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) * this work running on different CPUs so they don't try
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) * to register again already registered handler.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) mutex_lock(&kgdboc_reset_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) if (input_register_handler(&kgdboc_reset_handler) == 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) input_unregister_handler(&kgdboc_reset_handler);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) mutex_unlock(&kgdboc_reset_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) static DECLARE_WORK(kgdboc_restore_input_work, kgdboc_restore_input_helper);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) static void kgdboc_restore_input(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) if (likely(system_state == SYSTEM_RUNNING))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) schedule_work(&kgdboc_restore_input_work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) static int kgdboc_register_kbd(char **cptr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) if (strncmp(*cptr, "kbd", 3) == 0 ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) strncmp(*cptr, "kdb", 3) == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) if (kdb_poll_idx < KDB_POLL_FUNC_MAX) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) kdb_poll_funcs[kdb_poll_idx] = kdb_get_kbd_char;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) kdb_poll_idx++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) if (cptr[0][3] == ',')
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) *cptr += 4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) static void kgdboc_unregister_kbd(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) int i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) for (i = 0; i < kdb_poll_idx; i++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) if (kdb_poll_funcs[i] == kdb_get_kbd_char) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) kdb_poll_idx--;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) kdb_poll_funcs[i] = kdb_poll_funcs[kdb_poll_idx];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) kdb_poll_funcs[kdb_poll_idx] = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) i--;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) flush_work(&kgdboc_restore_input_work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) #else /* ! CONFIG_KDB_KEYBOARD */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) #define kgdboc_register_kbd(x) 0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) #define kgdboc_unregister_kbd()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) #define kgdboc_restore_input()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) #endif /* ! CONFIG_KDB_KEYBOARD */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) #if IS_BUILTIN(CONFIG_KGDB_SERIAL_CONSOLE)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) static void cleanup_earlycon(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) if (kgdboc_earlycon_io_ops.cons)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) kgdb_unregister_io_module(&kgdboc_earlycon_io_ops);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) #else /* !IS_BUILTIN(CONFIG_KGDB_SERIAL_CONSOLE) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) static inline void cleanup_earlycon(void) { }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) #endif /* !IS_BUILTIN(CONFIG_KGDB_SERIAL_CONSOLE) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) static void cleanup_kgdboc(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) cleanup_earlycon();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) if (configured != 1)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) if (kgdb_unregister_nmi_console())
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) kgdboc_unregister_kbd();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) kgdb_unregister_io_module(&kgdboc_io_ops);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) static int configure_kgdboc(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) struct tty_driver *p;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) int tty_line = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) int err = -ENODEV;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) char *cptr = config;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) struct console *cons;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) if (!strlen(config) || isspace(config[0])) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) goto noconfig;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) kgdboc_io_ops.cons = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) kgdb_tty_driver = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) kgdboc_use_kms = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) if (strncmp(cptr, "kms,", 4) == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) cptr += 4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) kgdboc_use_kms = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) if (kgdboc_register_kbd(&cptr))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) goto do_register;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) p = tty_find_polling_driver(cptr, &tty_line);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) if (!p)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) goto noconfig;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) for_each_console(cons) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) int idx;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) if (cons->device && cons->device(cons, &idx) == p &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) idx == tty_line) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) kgdboc_io_ops.cons = cons;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) kgdb_tty_driver = p;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) kgdb_tty_line = tty_line;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) do_register:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) err = kgdb_register_io_module(&kgdboc_io_ops);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) goto noconfig;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) err = kgdb_register_nmi_console();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) goto nmi_con_failed;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) configured = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) nmi_con_failed:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) kgdb_unregister_io_module(&kgdboc_io_ops);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) noconfig:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) kgdboc_unregister_kbd();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) configured = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) static int kgdboc_probe(struct platform_device *pdev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) int ret = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) mutex_lock(&config_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) if (configured != 1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) ret = configure_kgdboc();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) /* Convert "no device" to "defer" so we'll keep trying */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) if (ret == -ENODEV)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) ret = -EPROBE_DEFER;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) mutex_unlock(&config_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) static struct platform_driver kgdboc_platform_driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) .probe = kgdboc_probe,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) .driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) .name = "kgdboc",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) .suppress_bind_attrs = true,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) static int __init init_kgdboc(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) * kgdboc is a little bit of an odd "platform_driver". It can be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) * up and running long before the platform_driver object is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) * created and thus doesn't actually store anything in it. There's
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) * only one instance of kgdb so anything is stored as global state.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) * The platform_driver is only created so that we can leverage the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) * kernel's mechanisms (like -EPROBE_DEFER) to call us when our
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) * underlying tty is ready. Here we init our platform driver and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) * then create the single kgdboc instance.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) ret = platform_driver_register(&kgdboc_platform_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) kgdboc_pdev = platform_device_alloc("kgdboc", PLATFORM_DEVID_NONE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) if (!kgdboc_pdev) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) ret = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) goto err_did_register;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) ret = platform_device_add(kgdboc_pdev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) if (!ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) platform_device_put(kgdboc_pdev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) err_did_register:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) platform_driver_unregister(&kgdboc_platform_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) static void exit_kgdboc(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) mutex_lock(&config_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) cleanup_kgdboc();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) mutex_unlock(&config_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) platform_device_unregister(kgdboc_pdev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) platform_driver_unregister(&kgdboc_platform_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) static int kgdboc_get_char(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) if (!kgdb_tty_driver)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) return -1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) return kgdb_tty_driver->ops->poll_get_char(kgdb_tty_driver,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) kgdb_tty_line);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) static void kgdboc_put_char(u8 chr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310) if (!kgdb_tty_driver)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) kgdb_tty_driver->ops->poll_put_char(kgdb_tty_driver,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) kgdb_tty_line, chr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) static int param_set_kgdboc_var(const char *kmessage,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) const struct kernel_param *kp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) size_t len = strlen(kmessage);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) int ret = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) if (len >= MAX_CONFIG_LEN) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) pr_err("config string too long\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) return -ENOSPC;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) if (kgdb_connected) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) pr_err("Cannot reconfigure while KGDB is connected.\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) return -EBUSY;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) mutex_lock(&config_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) strcpy(config, kmessage);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) /* Chop out \n char as a result of echo */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) if (len && config[len - 1] == '\n')
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337) config[len - 1] = '\0';
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) if (configured == 1)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) cleanup_kgdboc();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) * Configure with the new params as long as init already ran.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344) * Note that we can get called before init if someone loads us
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345) * with "modprobe kgdboc kgdboc=..." or if they happen to use the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346) * the odd syntax of "kgdboc.kgdboc=..." on the kernel command.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348) if (configured >= 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) ret = configure_kgdboc();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352) * If we couldn't configure then clear out the config. Note that
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353) * specifying an invalid config on the kernel command line vs.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354) * through sysfs have slightly different behaviors. If we fail
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355) * to configure what was specified on the kernel command line
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356) * we'll leave it in the 'config' and return -EPROBE_DEFER from
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357) * our probe. When specified through sysfs userspace is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358) * responsible for loading the tty driver before setting up.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361) config[0] = '\0';
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363) mutex_unlock(&config_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 366) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 367)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 368) static int dbg_restore_graphics;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 369)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 370) static void kgdboc_pre_exp_handler(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 371) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 372) if (!dbg_restore_graphics && kgdboc_use_kms) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 373) dbg_restore_graphics = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 374) con_debug_enter(vc_cons[fg_console].d);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 375) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 376) /* Increment the module count when the debugger is active */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 377) if (!kgdb_connected)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 378) try_module_get(THIS_MODULE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 379) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 380)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 381) static void kgdboc_post_exp_handler(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 382) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 383) /* decrement the module count when the debugger detaches */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 384) if (!kgdb_connected)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 385) module_put(THIS_MODULE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 386) if (kgdboc_use_kms && dbg_restore_graphics) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 387) dbg_restore_graphics = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 388) con_debug_leave();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 389) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 390) kgdboc_restore_input();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 391) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 392)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 393) static struct kgdb_io kgdboc_io_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 394) .name = "kgdboc",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 395) .read_char = kgdboc_get_char,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 396) .write_char = kgdboc_put_char,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 397) .pre_exception = kgdboc_pre_exp_handler,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 398) .post_exception = kgdboc_post_exp_handler,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 399) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 400)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 401) #if IS_BUILTIN(CONFIG_KGDB_SERIAL_CONSOLE)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 402) static int kgdboc_option_setup(char *opt)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 403) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 404) if (!opt) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 405) pr_err("config string not provided\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 406) return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 407) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 408)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 409) if (strlen(opt) >= MAX_CONFIG_LEN) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 410) pr_err("config string too long\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 411) return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 412) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 413) strcpy(config, opt);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 414)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 415) return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 416) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 417)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 418) __setup("kgdboc=", kgdboc_option_setup);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 419)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 420)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 421) /* This is only available if kgdboc is a built in for early debugging */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 422) static int __init kgdboc_early_init(char *opt)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 423) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 424) kgdboc_option_setup(opt);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 425) configure_kgdboc();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 426) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 427) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 428)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 429) early_param("ekgdboc", kgdboc_early_init);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 430)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 431) static int kgdboc_earlycon_get_char(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 432) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 433) char c;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 434)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 435) if (!kgdboc_earlycon_io_ops.cons->read(kgdboc_earlycon_io_ops.cons,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 436) &c, 1))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 437) return NO_POLL_CHAR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 438)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 439) return c;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 440) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 441)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 442) static void kgdboc_earlycon_put_char(u8 chr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 443) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 444) kgdboc_earlycon_io_ops.cons->write(kgdboc_earlycon_io_ops.cons, &chr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 445) 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 446) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 447)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 448) static void kgdboc_earlycon_pre_exp_handler(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 449) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 450) struct console *con;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 451) static bool already_warned;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 452)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 453) if (already_warned)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 454) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 455)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 456) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 457) * When the first normal console comes up the kernel will take all
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 458) * the boot consoles out of the list. Really, we should stop using
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 459) * the boot console when it does that but until a TTY is registered
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 460) * we have no other choice so we keep using it. Since not all
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 461) * serial drivers might be OK with this, print a warning once per
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 462) * boot if we detect this case.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 463) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 464) for_each_console(con)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 465) if (con == kgdboc_earlycon_io_ops.cons)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 466) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 467)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 468) already_warned = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 469) pr_warn("kgdboc_earlycon is still using bootconsole\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 470) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 471)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 472) static int kgdboc_earlycon_deferred_exit(struct console *con)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 473) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 474) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 475) * If we get here it means the boot console is going away but we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 476) * don't yet have a suitable replacement. Don't pass through to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 477) * the original exit routine. We'll call it later in our deinit()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 478) * function. For now, restore the original exit() function pointer
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 479) * as a sentinal that we've hit this point.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 480) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 481) con->exit = earlycon_orig_exit;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 482)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 483) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 484) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 485)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 486) static void kgdboc_earlycon_deinit(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 487) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 488) if (!kgdboc_earlycon_io_ops.cons)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 489) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 490)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 491) if (kgdboc_earlycon_io_ops.cons->exit == kgdboc_earlycon_deferred_exit)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 492) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 493) * kgdboc_earlycon is exiting but original boot console exit
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 494) * was never called (AKA kgdboc_earlycon_deferred_exit()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 495) * didn't ever run). Undo our trap.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 496) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 497) kgdboc_earlycon_io_ops.cons->exit = earlycon_orig_exit;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 498) else if (kgdboc_earlycon_io_ops.cons->exit)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 499) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 500) * We skipped calling the exit() routine so we could try to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 501) * keep using the boot console even after it went away. We're
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 502) * finally done so call the function now.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 503) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 504) kgdboc_earlycon_io_ops.cons->exit(kgdboc_earlycon_io_ops.cons);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 505)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 506) kgdboc_earlycon_io_ops.cons = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 507) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 508)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 509) static struct kgdb_io kgdboc_earlycon_io_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 510) .name = "kgdboc_earlycon",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 511) .read_char = kgdboc_earlycon_get_char,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 512) .write_char = kgdboc_earlycon_put_char,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 513) .pre_exception = kgdboc_earlycon_pre_exp_handler,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 514) .deinit = kgdboc_earlycon_deinit,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 515) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 516)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 517) #define MAX_CONSOLE_NAME_LEN (sizeof((struct console *) 0)->name)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 518) static char kgdboc_earlycon_param[MAX_CONSOLE_NAME_LEN] __initdata;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 519) static bool kgdboc_earlycon_late_enable __initdata;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 520)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 521) static int __init kgdboc_earlycon_init(char *opt)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 522) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 523) struct console *con;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 524)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 525) kdb_init(KDB_INIT_EARLY);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 526)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 527) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 528) * Look for a matching console, or if the name was left blank just
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 529) * pick the first one we find.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 530) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 531) console_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 532) for_each_console(con) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 533) if (con->write && con->read &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 534) (con->flags & (CON_BOOT | CON_ENABLED)) &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 535) (!opt || !opt[0] || strcmp(con->name, opt) == 0))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 536) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 537) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 538)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 539) if (!con) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 540) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 541) * Both earlycon and kgdboc_earlycon are initialized during
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 542) * early parameter parsing. We cannot guarantee earlycon gets
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 543) * in first and, in any case, on ACPI systems earlycon may
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 544) * defer its own initialization (usually to somewhere within
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 545) * setup_arch() ). To cope with either of these situations
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 546) * we can defer our own initialization to a little later in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 547) * the boot.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 548) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 549) if (!kgdboc_earlycon_late_enable) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 550) pr_info("No suitable earlycon yet, will try later\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 551) if (opt)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 552) strscpy(kgdboc_earlycon_param, opt,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 553) sizeof(kgdboc_earlycon_param));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 554) kgdboc_earlycon_late_enable = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 555) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 556) pr_info("Couldn't find kgdb earlycon\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 557) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 558) goto unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 559) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 560)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 561) kgdboc_earlycon_io_ops.cons = con;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 562) pr_info("Going to register kgdb with earlycon '%s'\n", con->name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 563) if (kgdb_register_io_module(&kgdboc_earlycon_io_ops) != 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 564) kgdboc_earlycon_io_ops.cons = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 565) pr_info("Failed to register kgdb with earlycon\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 566) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 567) /* Trap exit so we can keep earlycon longer if needed. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 568) earlycon_orig_exit = con->exit;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 569) con->exit = kgdboc_earlycon_deferred_exit;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 570) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 571)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 572) unlock:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 573) console_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 574)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 575) /* Non-zero means malformed option so we always return zero */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 576) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 577) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 578)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 579) early_param("kgdboc_earlycon", kgdboc_earlycon_init);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 580)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 581) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 582) * This is only intended for the late adoption of an early console.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 583) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 584) * It is not a reliable way to adopt regular consoles because we can not
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 585) * control what order console initcalls are made and, in any case, many
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 586) * regular consoles are registered much later in the boot process than
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 587) * the console initcalls!
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 588) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 589) static int __init kgdboc_earlycon_late_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 590) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 591) if (kgdboc_earlycon_late_enable)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 592) kgdboc_earlycon_init(kgdboc_earlycon_param);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 593) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 594) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 595) console_initcall(kgdboc_earlycon_late_init);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 596)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 597) #endif /* IS_BUILTIN(CONFIG_KGDB_SERIAL_CONSOLE) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 598)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 599) module_init(init_kgdboc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 600) module_exit(exit_kgdboc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 601) module_param_call(kgdboc, param_set_kgdboc_var, param_get_string, &kps, 0644);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 602) MODULE_PARM_DESC(kgdboc, "<serial_device>[,baud]");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 603) MODULE_DESCRIPTION("KGDB Console TTY Driver");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 604) MODULE_LICENSE("GPL");
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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