arch/powerpc/kernel/udbg.c

   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_LPAR_HVSI)
  35         /* For LPAR machines that have an HVSI console on vterm 0 */
  36         udbg_init_debug_lpar_hvsi();
  37 #elif defined(CONFIG_PPC_EARLY_DEBUG_G5)
  38         /* For use on Apple G5 machines */
  39         udbg_init_pmac_realmode();
  40 #elif defined(CONFIG_PPC_EARLY_DEBUG_RTAS_PANEL)
  41         /* RTAS panel debug */
  42         udbg_init_rtas_panel();
  43 #elif defined(CONFIG_PPC_EARLY_DEBUG_RTAS_CONSOLE)
  44         /* RTAS console debug */
  45         udbg_init_rtas_console();
  46 #elif defined(CONFIG_PPC_EARLY_DEBUG_MAPLE)
  47         /* Maple real mode debug */
  48         udbg_init_maple_realmode();
  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 #elif defined(CONFIG_PPC_EARLY_DEBUG_USBGECKO)
  64         udbg_init_usbgecko();
  65 #elif defined(CONFIG_PPC_EARLY_DEBUG_WSP)
  66         udbg_init_wsp();
  67 #elif defined(CONFIG_PPC_EARLY_DEBUG_EHV_BC)
  68         udbg_init_ehv_bc();
  69 #elif defined(CONFIG_PPC_EARLY_DEBUG_PS3GELIC)
  70         udbg_init_ps3gelic();
  71 #elif defined(CONFIG_PPC_EARLY_DEBUG_OPAL_RAW)
  72         udbg_init_debug_opal_raw();
  73 #elif defined(CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI)
  74         udbg_init_debug_opal_hvsi();
  75 #endif
  76
  77 #ifdef CONFIG_PPC_EARLY_DEBUG
  78         console_loglevel = 10;
  79
  80         register_early_udbg_console();
  81 #endif
  82 }
  83
  84 /* udbg library, used by xmon et al */
  85 void udbg_puts(const char *s)
  86 {
  87         if (udbg_putc) {
  88                 char c;
  89
  90                 if (s && *s != '\0') {
  91                         while ((c = *s++) != '\0')
  92                                 udbg_putc(c);
  93                 }
  94
  95                 if (udbg_flush)
  96                         udbg_flush();
  97         }
  98 #if 0
  99         else {
 100                 printk("%s", s);
 101         }
 102 #endif
 103 }
 104
 105 int udbg_write(const char *s, int n)
 106 {
 107         int remain = n;
 108         char c;
 109
 110         if (!udbg_putc)
 111                 return 0;
 112
 113         if (s && *s != '\0') {
 114                 while (((c = *s++) != '\0') && (remain-- > 0)) {
 115                         udbg_putc(c);
 116                 }
 117         }
 118
 119         if (udbg_flush)
 120                 udbg_flush();
 121
 122         return n - remain;
 123 }
 124
 125 int udbg_read(char *buf, int buflen)
 126 {
 127         char *p = buf;
 128         int i, c;
 129
 130         if (!udbg_getc)
 131                 return 0;
 132
 133         for (i = 0; i < buflen; ++i) {
 134                 do {
 135                         c = udbg_getc();
 136                         if (c == -1 && i == 0)
 137                                 return -1;
 138
 139                 } while (c == 0x11 || c == 0x13);
 140                 if (c == 0 || c == -1)
 141                         break;
 142                 *p++ = c;
 143         }
 144
 145         return i;
 146 }
 147
 148 #define UDBG_BUFSIZE 256
 149 void udbg_printf(const char *fmt, ...)
 150 {
 151         char buf[UDBG_BUFSIZE];
 152         va_list args;
 153
 154         va_start(args, fmt);
 155         vsnprintf(buf, UDBG_BUFSIZE, fmt, args);
 156         udbg_puts(buf);
 157         va_end(args);
 158 }
 159
 160 void __init udbg_progress(char *s, unsigned short hex)
 161 {
 162         udbg_puts(s);
 163         udbg_puts("\n");
 164 }
 165
 166 /*
 167  * Early boot console based on udbg
 168  */
 169 static void udbg_console_write(struct console *con, const char *s,
 170                 unsigned int n)
 171 {
 172         udbg_write(s, n);
 173 }
 174
 175 static struct console udbg_console = {
 176         .name   = "udbg",
 177         .write  = udbg_console_write,
 178         .flags  = CON_PRINTBUFFER | CON_ENABLED | CON_BOOT | CON_ANYTIME,
 179         .index  = 0,
 180 };
 181
 182 static int early_console_initialized;
 183
 184 /*
 185  * Called by setup_system after ppc_md->probe and ppc_md->early_init.
 186  * Call it again after setting udbg_putc in ppc_md->setup_arch.
 187  */
 188 void __init register_early_udbg_console(void)
 189 {
 190         if (early_console_initialized)
 191                 return;
 192
 193         if (!udbg_putc)
 194                 return;
 195
 196         if (strstr(boot_command_line, "udbg-immortal")) {
 197                 printk(KERN_INFO "early console immortal !\n");
 198                 udbg_console.flags &= ~CON_BOOT;
 199         }
 200         early_console_initialized = 1;
 201         register_console(&udbg_console);
 202 }
 203
 204 #if 0   /* if you want to use this as a regular output console */
 205 console_initcall(register_udbg_console);
 206 #endif