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 #elif defined(CONFIG_PPC_EARLY_DEBUG_16550) 71 udbg_init_debug_16550(); 72 #endif 73 74 #ifdef CONFIG_PPC_EARLY_DEBUG 75 console_loglevel = CONSOLE_LOGLEVEL_DEBUG; 76 77 register_early_udbg_console(); 78 #endif 79 } 80 81 /* udbg library, used by xmon et al */ 82 void udbg_puts(const char *s) 83 { 84 if (udbg_putc) { 85 char c; 86 87 if (s && *s != '\0') { 88 while ((c = *s++) != '\0') 89 udbg_putc(c); 90 } 91 92 if (udbg_flush) 93 udbg_flush(); 94 } 95 #if 0 96 else { 97 printk("%s", s); 98 } 99 #endif 100 } 101 102 int udbg_write(const char *s, int n) 103 { 104 int remain = n; 105 char c; 106 107 if (!udbg_putc) 108 return 0; 109 110 if (s && *s != '\0') { 111 while (((c = *s++) != '\0') && (remain-- > 0)) { 112 udbg_putc(c); 113 } 114 } 115 116 if (udbg_flush) 117 udbg_flush(); 118 119 return n - remain; 120 } 121 122 #define UDBG_BUFSIZE 256 123 void udbg_printf(const char *fmt, ...) 124 { 125 if (udbg_putc) { 126 char buf[UDBG_BUFSIZE]; 127 va_list args; 128 129 va_start(args, fmt); 130 vsnprintf(buf, UDBG_BUFSIZE, fmt, args); 131 udbg_puts(buf); 132 va_end(args); 133 } 134 } 135 136 void __init udbg_progress(char *s, unsigned short hex) 137 { 138 udbg_puts(s); 139 udbg_puts("\n"); 140 } 141 142 /* 143 * Early boot console based on udbg 144 */ 145 static void udbg_console_write(struct console *con, const char *s, 146 unsigned int n) 147 { 148 udbg_write(s, n); 149 } 150 151 static struct console udbg_console = { 152 .name = "udbg", 153 .write = udbg_console_write, 154 .flags = CON_PRINTBUFFER | CON_ENABLED | CON_BOOT | CON_ANYTIME, 155 .index = 0, 156 }; 157 158 /* 159 * Called by setup_system after ppc_md->probe and ppc_md->early_init. 160 * Call it again after setting udbg_putc in ppc_md->setup_arch. 161 */ 162 void __init register_early_udbg_console(void) 163 { 164 if (early_console) 165 return; 166 167 if (!udbg_putc) 168 return; 169 170 if (strstr(boot_command_line, "udbg-immortal")) { 171 printk(KERN_INFO "early console immortal !\n"); 172 udbg_console.flags &= ~CON_BOOT; 173 } 174 early_console = &udbg_console; 175 register_console(&udbg_console); 176 } 177 178 #if 0 /* if you want to use this as a regular output console */ 179 console_initcall(register_udbg_console); 180 #endif 181