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 void (*udbg_flush)(void); 22 int (*udbg_getc)(void); 23 int (*udbg_getc_poll)(void); 24 25 /* 26 * Early debugging facilities. You can enable _one_ of these via .config, 27 * if you do so your kernel _will not boot_ on anything else. Be careful. 28 */ 29 void __init udbg_early_init(void) 30 { 31 #if defined(CONFIG_PPC_EARLY_DEBUG_LPAR) 32 /* For LPAR machines that have an HVC console on vterm 0 */ 33 udbg_init_debug_lpar(); 34 #elif defined(CONFIG_PPC_EARLY_DEBUG_G5) 35 /* For use on Apple G5 machines */ 36 udbg_init_pmac_realmode(); 37 #elif defined(CONFIG_PPC_EARLY_DEBUG_RTAS_PANEL) 38 /* RTAS panel debug */ 39 udbg_init_rtas_panel(); 40 #elif defined(CONFIG_PPC_EARLY_DEBUG_RTAS_CONSOLE) 41 /* RTAS console debug */ 42 udbg_init_rtas_console(); 43 #elif defined(CONFIG_PPC_EARLY_DEBUG_MAPLE) 44 /* Maple real mode debug */ 45 udbg_init_maple_realmode(); 46 #elif defined(CONFIG_PPC_EARLY_DEBUG_ISERIES) 47 /* For iSeries - hit Ctrl-x Ctrl-x to see the output */ 48 udbg_init_iseries(); 49 #elif defined(CONFIG_PPC_EARLY_DEBUG_BEAT) 50 udbg_init_debug_beat(); 51 #elif defined(CONFIG_PPC_EARLY_DEBUG_PAS_REALMODE) 52 udbg_init_pas_realmode(); 53 #elif defined(CONFIG_BOOTX_TEXT) 54 udbg_init_btext(); 55 #elif defined(CONFIG_PPC_EARLY_DEBUG_44x) 56 /* PPC44x debug */ 57 udbg_init_44x_as1(); 58 #elif defined(CONFIG_PPC_EARLY_DEBUG_40x) 59 /* PPC40x debug */ 60 udbg_init_40x_realmode(); 61 #elif defined(CONFIG_PPC_EARLY_DEBUG_CPM) 62 udbg_init_cpm(); 63 #endif 64 65 #ifdef CONFIG_PPC_EARLY_DEBUG 66 console_loglevel = 10; 67 #endif 68 } 69 70 /* udbg library, used by xmon et al */ 71 void udbg_puts(const char *s) 72 { 73 if (udbg_putc) { 74 char c; 75 76 if (s && *s != '\0') { 77 while ((c = *s++) != '\0') 78 udbg_putc(c); 79 } 80 81 if (udbg_flush) 82 udbg_flush(); 83 } 84 #if 0 85 else { 86 printk("%s", s); 87 } 88 #endif 89 } 90 91 int udbg_write(const char *s, int n) 92 { 93 int remain = n; 94 char c; 95 96 if (!udbg_putc) 97 return 0; 98 99 if (s && *s != '\0') { 100 while (((c = *s++) != '\0') && (remain-- > 0)) { 101 udbg_putc(c); 102 } 103 } 104 105 if (udbg_flush) 106 udbg_flush(); 107 108 return n - remain; 109 } 110 111 int udbg_read(char *buf, int buflen) 112 { 113 char *p = buf; 114 int i, c; 115 116 if (!udbg_getc) 117 return 0; 118 119 for (i = 0; i < buflen; ++i) { 120 do { 121 c = udbg_getc(); 122 if (c == -1 && i == 0) 123 return -1; 124 125 } while (c == 0x11 || c == 0x13); 126 if (c == 0 || c == -1) 127 break; 128 *p++ = c; 129 } 130 131 return i; 132 } 133 134 #define UDBG_BUFSIZE 256 135 void udbg_printf(const char *fmt, ...) 136 { 137 char buf[UDBG_BUFSIZE]; 138 va_list args; 139 140 va_start(args, fmt); 141 vsnprintf(buf, UDBG_BUFSIZE, fmt, args); 142 udbg_puts(buf); 143 va_end(args); 144 } 145 146 void __init udbg_progress(char *s, unsigned short hex) 147 { 148 udbg_puts(s); 149 udbg_puts("\n"); 150 } 151 152 /* 153 * Early boot console based on udbg 154 */ 155 static void udbg_console_write(struct console *con, const char *s, 156 unsigned int n) 157 { 158 udbg_write(s, n); 159 } 160 161 static struct console udbg_console = { 162 .name = "udbg", 163 .write = udbg_console_write, 164 .flags = CON_PRINTBUFFER | CON_ENABLED | CON_BOOT | CON_ANYTIME, 165 .index = 0, 166 }; 167 168 static int early_console_initialized; 169 170 /* 171 * Called by setup_system after ppc_md->probe and ppc_md->early_init. 172 * Call it again after setting udbg_putc in ppc_md->setup_arch. 173 */ 174 void __init register_early_udbg_console(void) 175 { 176 if (early_console_initialized) 177 return; 178 179 if (!udbg_putc) 180 return; 181 182 if (strstr(boot_command_line, "udbg-immortal")) { 183 printk(KERN_INFO "early console immortal !\n"); 184 udbg_console.flags &= ~CON_BOOT; 185 } 186 early_console_initialized = 1; 187 register_console(&udbg_console); 188 } 189 190 #if 0 /* if you want to use this as a regular output console */ 191 console_initcall(register_udbg_console); 192 #endif 193