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_PAS_REALMODE) 43 udbg_init_pas_realmode(); 44 #elif defined(CONFIG_PPC_EARLY_DEBUG_BOOTX) 45 udbg_init_btext(); 46 #elif defined(CONFIG_PPC_EARLY_DEBUG_44x) 47 /* PPC44x debug */ 48 udbg_init_44x_as1(); 49 #elif defined(CONFIG_PPC_EARLY_DEBUG_CPM) 50 udbg_init_cpm(); 51 #elif defined(CONFIG_PPC_EARLY_DEBUG_USBGECKO) 52 udbg_init_usbgecko(); 53 #elif defined(CONFIG_PPC_EARLY_DEBUG_MEMCONS) 54 /* In memory console */ 55 udbg_init_memcons(); 56 #elif defined(CONFIG_PPC_EARLY_DEBUG_EHV_BC) 57 udbg_init_ehv_bc(); 58 #elif defined(CONFIG_PPC_EARLY_DEBUG_PS3GELIC) 59 udbg_init_ps3gelic(); 60 #elif defined(CONFIG_PPC_EARLY_DEBUG_OPAL_RAW) 61 udbg_init_debug_opal_raw(); 62 #elif defined(CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI) 63 udbg_init_debug_opal_hvsi(); 64 #elif defined(CONFIG_PPC_EARLY_DEBUG_16550) 65 udbg_init_debug_16550(); 66 #endif 67 68 #ifdef CONFIG_PPC_EARLY_DEBUG 69 console_loglevel = CONSOLE_LOGLEVEL_DEBUG; 70 71 register_early_udbg_console(); 72 #endif 73 } 74 75 /* udbg library, used by xmon et al */ 76 void udbg_puts(const char *s) 77 { 78 if (udbg_putc) { 79 char c; 80 81 if (s && *s != '\0') { 82 while ((c = *s++) != '\0') 83 udbg_putc(c); 84 } 85 86 if (udbg_flush) 87 udbg_flush(); 88 } 89 #if 0 90 else { 91 printk("%s", s); 92 } 93 #endif 94 } 95 96 int udbg_write(const char *s, int n) 97 { 98 int remain = n; 99 char c; 100 101 if (!udbg_putc) 102 return 0; 103 104 if (s && *s != '\0') { 105 while (((c = *s++) != '\0') && (remain-- > 0)) { 106 udbg_putc(c); 107 } 108 } 109 110 if (udbg_flush) 111 udbg_flush(); 112 113 return n - remain; 114 } 115 116 #define UDBG_BUFSIZE 256 117 void udbg_printf(const char *fmt, ...) 118 { 119 if (udbg_putc) { 120 char buf[UDBG_BUFSIZE]; 121 va_list args; 122 123 va_start(args, fmt); 124 vsnprintf(buf, UDBG_BUFSIZE, fmt, args); 125 udbg_puts(buf); 126 va_end(args); 127 } 128 } 129 130 void __init udbg_progress(char *s, unsigned short hex) 131 { 132 udbg_puts(s); 133 udbg_puts("\n"); 134 } 135 136 /* 137 * Early boot console based on udbg 138 */ 139 static void udbg_console_write(struct console *con, const char *s, 140 unsigned int n) 141 { 142 udbg_write(s, n); 143 } 144 145 static struct console udbg_console = { 146 .name = "udbg", 147 .write = udbg_console_write, 148 .flags = CON_PRINTBUFFER | CON_ENABLED | CON_BOOT | CON_ANYTIME, 149 .index = 0, 150 }; 151 152 /* 153 * Called by setup_system after ppc_md->probe and ppc_md->early_init. 154 * Call it again after setting udbg_putc in ppc_md->setup_arch. 155 */ 156 void __init register_early_udbg_console(void) 157 { 158 if (early_console) 159 return; 160 161 if (!udbg_putc) 162 return; 163 164 if (strstr(boot_command_line, "udbg-immortal")) { 165 printk(KERN_INFO "early console immortal !\n"); 166 udbg_console.flags &= ~CON_BOOT; 167 } 168 early_console = &udbg_console; 169 register_console(&udbg_console); 170 } 171 172 #if 0 /* if you want to use this as a regular output console */ 173 console_initcall(register_udbg_console); 174 #endif 175