1 /* 2 * polling mode stateless debugging stuff, originally for NS16550 Serial Ports 3 * 4 * c 2001 PPC 64 Team, IBM Corp 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 9 * 2 of the License, or (at your option) any later version. 10 */ 11 12 #include <stdarg.h> 13 #include <linux/types.h> 14 #include <linux/sched.h> 15 #include <linux/console.h> 16 #include <linux/init.h> 17 #include <asm/processor.h> 18 #include <asm/udbg.h> 19 20 void (*udbg_putc)(char c); 21 int (*udbg_getc)(void); 22 int (*udbg_getc_poll)(void); 23 24 /* 25 * Early debugging facilities. You can enable _one_ of these via .config, 26 * if you do so your kernel _will not boot_ on anything else. Be careful. 27 */ 28 void __init udbg_early_init(void) 29 { 30 #if defined(CONFIG_PPC_EARLY_DEBUG_LPAR) 31 /* For LPAR machines that have an HVC console on vterm 0 */ 32 udbg_init_debug_lpar(); 33 #elif defined(CONFIG_PPC_EARLY_DEBUG_G5) 34 /* For use on Apple G5 machines */ 35 udbg_init_pmac_realmode(); 36 #elif defined(CONFIG_PPC_EARLY_DEBUG_RTAS_PANEL) 37 /* RTAS panel debug */ 38 udbg_init_rtas_panel(); 39 #elif defined(CONFIG_PPC_EARLY_DEBUG_RTAS_CONSOLE) 40 /* RTAS console debug */ 41 udbg_init_rtas_console(); 42 #elif defined(CONFIG_PPC_EARLY_DEBUG_MAPLE) 43 /* Maple real mode debug */ 44 udbg_init_maple_realmode(); 45 #elif defined(CONFIG_PPC_EARLY_DEBUG_ISERIES) 46 /* For iSeries - hit Ctrl-x Ctrl-x to see the output */ 47 udbg_init_iseries(); 48 #elif defined(CONFIG_PPC_EARLY_DEBUG_BEAT) 49 udbg_init_debug_beat(); 50 #elif defined(CONFIG_PPC_EARLY_DEBUG_PAS_REALMODE) 51 udbg_init_pas_realmode(); 52 #elif defined(CONFIG_BOOTX_TEXT) 53 udbg_init_btext(); 54 #elif defined(CONFIG_PPC_EARLY_DEBUG_44x) 55 /* PPC44x debug */ 56 udbg_init_44x_as1(); 57 #elif defined(CONFIG_PPC_EARLY_DEBUG_40x) 58 /* PPC40x debug */ 59 udbg_init_40x_realmode(); 60 #elif defined(CONFIG_PPC_EARLY_DEBUG_CPM) 61 udbg_init_cpm(); 62 #endif 63 64 #ifdef CONFIG_PPC_EARLY_DEBUG 65 console_loglevel = 10; 66 #endif 67 } 68 69 /* udbg library, used by xmon et al */ 70 void udbg_puts(const char *s) 71 { 72 if (udbg_putc) { 73 char c; 74 75 if (s && *s != '\0') { 76 while ((c = *s++) != '\0') 77 udbg_putc(c); 78 } 79 } 80 #if 0 81 else { 82 printk("%s", s); 83 } 84 #endif 85 } 86 87 int udbg_write(const char *s, int n) 88 { 89 int remain = n; 90 char c; 91 92 if (!udbg_putc) 93 return 0; 94 95 if (s && *s != '\0') { 96 while (((c = *s++) != '\0') && (remain-- > 0)) { 97 udbg_putc(c); 98 } 99 } 100 101 return n - remain; 102 } 103 104 int udbg_read(char *buf, int buflen) 105 { 106 char *p = buf; 107 int i, c; 108 109 if (!udbg_getc) 110 return 0; 111 112 for (i = 0; i < buflen; ++i) { 113 do { 114 c = udbg_getc(); 115 if (c == -1 && i == 0) 116 return -1; 117 118 } while (c == 0x11 || c == 0x13); 119 if (c == 0 || c == -1) 120 break; 121 *p++ = c; 122 } 123 124 return i; 125 } 126 127 #define UDBG_BUFSIZE 256 128 void udbg_printf(const char *fmt, ...) 129 { 130 char buf[UDBG_BUFSIZE]; 131 va_list args; 132 133 va_start(args, fmt); 134 vsnprintf(buf, UDBG_BUFSIZE, fmt, args); 135 udbg_puts(buf); 136 va_end(args); 137 } 138 139 void __init udbg_progress(char *s, unsigned short hex) 140 { 141 udbg_puts(s); 142 udbg_puts("\n"); 143 } 144 145 /* 146 * Early boot console based on udbg 147 */ 148 static void udbg_console_write(struct console *con, const char *s, 149 unsigned int n) 150 { 151 udbg_write(s, n); 152 } 153 154 static struct console udbg_console = { 155 .name = "udbg", 156 .write = udbg_console_write, 157 .flags = CON_PRINTBUFFER | CON_ENABLED | CON_BOOT | CON_ANYTIME, 158 .index = 0, 159 }; 160 161 static int early_console_initialized; 162 163 /* 164 * Called by setup_system after ppc_md->probe and ppc_md->early_init. 165 * Call it again after setting udbg_putc in ppc_md->setup_arch. 166 */ 167 void __init register_early_udbg_console(void) 168 { 169 if (early_console_initialized) 170 return; 171 172 if (!udbg_putc) 173 return; 174 175 if (strstr(boot_command_line, "udbg-immortal")) { 176 printk(KERN_INFO "early console immortal !\n"); 177 udbg_console.flags &= ~CON_BOOT; 178 } 179 early_console_initialized = 1; 180 register_console(&udbg_console); 181 } 182 183 #if 0 /* if you want to use this as a regular output console */ 184 console_initcall(register_udbg_console); 185 #endif 186