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_CPM) 53 udbg_init_cpm(); 54 #elif defined(CONFIG_PPC_EARLY_DEBUG_USBGECKO) 55 udbg_init_usbgecko(); 56 #elif defined(CONFIG_PPC_EARLY_DEBUG_MEMCONS) 57 /* In memory console */ 58 udbg_init_memcons(); 59 #elif defined(CONFIG_PPC_EARLY_DEBUG_EHV_BC) 60 udbg_init_ehv_bc(); 61 #elif defined(CONFIG_PPC_EARLY_DEBUG_PS3GELIC) 62 udbg_init_ps3gelic(); 63 #elif defined(CONFIG_PPC_EARLY_DEBUG_OPAL_RAW) 64 udbg_init_debug_opal_raw(); 65 #elif defined(CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI) 66 udbg_init_debug_opal_hvsi(); 67 #elif defined(CONFIG_PPC_EARLY_DEBUG_16550) 68 udbg_init_debug_16550(); 69 #endif 70 71 #ifdef CONFIG_PPC_EARLY_DEBUG 72 console_loglevel = CONSOLE_LOGLEVEL_DEBUG; 73 74 register_early_udbg_console(); 75 #endif 76 } 77 78 /* udbg library, used by xmon et al */ 79 void udbg_puts(const char *s) 80 { 81 if (udbg_putc) { 82 char c; 83 84 if (s && *s != '\0') { 85 while ((c = *s++) != '\0') 86 udbg_putc(c); 87 } 88 89 if (udbg_flush) 90 udbg_flush(); 91 } 92 #if 0 93 else { 94 printk("%s", s); 95 } 96 #endif 97 } 98 99 int udbg_write(const char *s, int n) 100 { 101 int remain = n; 102 char c; 103 104 if (!udbg_putc) 105 return 0; 106 107 if (s && *s != '\0') { 108 while (((c = *s++) != '\0') && (remain-- > 0)) { 109 udbg_putc(c); 110 } 111 } 112 113 if (udbg_flush) 114 udbg_flush(); 115 116 return n - remain; 117 } 118 119 #define UDBG_BUFSIZE 256 120 void udbg_printf(const char *fmt, ...) 121 { 122 if (udbg_putc) { 123 char buf[UDBG_BUFSIZE]; 124 va_list args; 125 126 va_start(args, fmt); 127 vsnprintf(buf, UDBG_BUFSIZE, fmt, args); 128 udbg_puts(buf); 129 va_end(args); 130 } 131 } 132 133 void __init udbg_progress(char *s, unsigned short hex) 134 { 135 udbg_puts(s); 136 udbg_puts("\n"); 137 } 138 139 /* 140 * Early boot console based on udbg 141 */ 142 static void udbg_console_write(struct console *con, const char *s, 143 unsigned int n) 144 { 145 udbg_write(s, n); 146 } 147 148 static struct console udbg_console = { 149 .name = "udbg", 150 .write = udbg_console_write, 151 .flags = CON_PRINTBUFFER | CON_ENABLED | CON_BOOT | CON_ANYTIME, 152 .index = 0, 153 }; 154 155 /* 156 * Called by setup_system after ppc_md->probe and ppc_md->early_init. 157 * Call it again after setting udbg_putc in ppc_md->setup_arch. 158 */ 159 void __init register_early_udbg_console(void) 160 { 161 if (early_console) 162 return; 163 164 if (!udbg_putc) 165 return; 166 167 if (strstr(boot_command_line, "udbg-immortal")) { 168 printk(KERN_INFO "early console immortal !\n"); 169 udbg_console.flags &= ~CON_BOOT; 170 } 171 early_console = &udbg_console; 172 register_console(&udbg_console); 173 } 174 175 #if 0 /* if you want to use this as a regular output console */ 176 console_initcall(register_udbg_console); 177 #endif 178