1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * polling mode stateless debugging stuff, originally for NS16550 Serial Ports 4 * 5 * c 2001 PPC 64 Team, IBM Corp 6 */ 7 8 #include <linux/stdarg.h> 9 #include <linux/types.h> 10 #include <linux/sched.h> 11 #include <linux/console.h> 12 #include <linux/init.h> 13 #include <asm/processor.h> 14 #include <asm/udbg.h> 15 16 void (*udbg_putc)(char c); 17 void (*udbg_flush)(void); 18 int (*udbg_getc)(void); 19 int (*udbg_getc_poll)(void); 20 21 /* 22 * Early debugging facilities. You can enable _one_ of these via .config, 23 * if you do so your kernel _will not boot_ on anything else. Be careful. 24 */ 25 void __init udbg_early_init(void) 26 { 27 #if defined(CONFIG_PPC_EARLY_DEBUG_LPAR) 28 /* For LPAR machines that have an HVC console on vterm 0 */ 29 udbg_init_debug_lpar(); 30 #elif defined(CONFIG_PPC_EARLY_DEBUG_LPAR_HVSI) 31 /* For LPAR machines that have an HVSI console on vterm 0 */ 32 udbg_init_debug_lpar_hvsi(); 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_PAS_REALMODE) 46 udbg_init_pas_realmode(); 47 #elif defined(CONFIG_PPC_EARLY_DEBUG_BOOTX) 48 udbg_init_btext(); 49 #elif defined(CONFIG_PPC_EARLY_DEBUG_44x) 50 /* PPC44x debug */ 51 udbg_init_44x_as1(); 52 #elif defined(CONFIG_PPC_EARLY_DEBUG_40x) 53 /* PPC40x debug */ 54 udbg_init_40x_realmode(); 55 #elif defined(CONFIG_PPC_EARLY_DEBUG_CPM) 56 udbg_init_cpm(); 57 #elif defined(CONFIG_PPC_EARLY_DEBUG_USBGECKO) 58 udbg_init_usbgecko(); 59 #elif defined(CONFIG_PPC_EARLY_DEBUG_MEMCONS) 60 /* In memory console */ 61 udbg_init_memcons(); 62 #elif defined(CONFIG_PPC_EARLY_DEBUG_EHV_BC) 63 udbg_init_ehv_bc(); 64 #elif defined(CONFIG_PPC_EARLY_DEBUG_PS3GELIC) 65 udbg_init_ps3gelic(); 66 #elif defined(CONFIG_PPC_EARLY_DEBUG_OPAL_RAW) 67 udbg_init_debug_opal_raw(); 68 #elif defined(CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI) 69 udbg_init_debug_opal_hvsi(); 70 #endif 71 72 #ifdef CONFIG_PPC_EARLY_DEBUG 73 console_loglevel = CONSOLE_LOGLEVEL_DEBUG; 74 75 register_early_udbg_console(); 76 #endif 77 } 78 79 /* udbg library, used by xmon et al */ 80 void udbg_puts(const char *s) 81 { 82 if (udbg_putc) { 83 char c; 84 85 if (s && *s != '\0') { 86 while ((c = *s++) != '\0') 87 udbg_putc(c); 88 } 89 90 if (udbg_flush) 91 udbg_flush(); 92 } 93 #if 0 94 else { 95 printk("%s", s); 96 } 97 #endif 98 } 99 100 int udbg_write(const char *s, int n) 101 { 102 int remain = n; 103 char c; 104 105 if (!udbg_putc) 106 return 0; 107 108 if (s && *s != '\0') { 109 while (((c = *s++) != '\0') && (remain-- > 0)) { 110 udbg_putc(c); 111 } 112 } 113 114 if (udbg_flush) 115 udbg_flush(); 116 117 return n - remain; 118 } 119 120 #define UDBG_BUFSIZE 256 121 void udbg_printf(const char *fmt, ...) 122 { 123 if (udbg_putc) { 124 char buf[UDBG_BUFSIZE]; 125 va_list args; 126 127 va_start(args, fmt); 128 vsnprintf(buf, UDBG_BUFSIZE, fmt, args); 129 udbg_puts(buf); 130 va_end(args); 131 } 132 } 133 134 void __init udbg_progress(char *s, unsigned short hex) 135 { 136 udbg_puts(s); 137 udbg_puts("\n"); 138 } 139 140 /* 141 * Early boot console based on udbg 142 */ 143 static void udbg_console_write(struct console *con, const char *s, 144 unsigned int n) 145 { 146 udbg_write(s, n); 147 } 148 149 static struct console udbg_console = { 150 .name = "udbg", 151 .write = udbg_console_write, 152 .flags = CON_PRINTBUFFER | CON_ENABLED | CON_BOOT | CON_ANYTIME, 153 .index = 0, 154 }; 155 156 /* 157 * Called by setup_system after ppc_md->probe and ppc_md->early_init. 158 * Call it again after setting udbg_putc in ppc_md->setup_arch. 159 */ 160 void __init register_early_udbg_console(void) 161 { 162 if (early_console) 163 return; 164 165 if (!udbg_putc) 166 return; 167 168 if (strstr(boot_command_line, "udbg-immortal")) { 169 printk(KERN_INFO "early console immortal !\n"); 170 udbg_console.flags &= ~CON_BOOT; 171 } 172 early_console = &udbg_console; 173 register_console(&udbg_console); 174 } 175 176 #if 0 /* if you want to use this as a regular output console */ 177 console_initcall(register_udbg_console); 178 #endif 179