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_PPC_EARLY_DEBUG_BOOTX)
  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_MEMCONS)
  66         /* In memory console */
  67         udbg_init_memcons();
  68 #elif defined(CONFIG_PPC_EARLY_DEBUG_EHV_BC)
  69         udbg_init_ehv_bc();
  70 #elif defined(CONFIG_PPC_EARLY_DEBUG_PS3GELIC)
  71         udbg_init_ps3gelic();
  72 #elif defined(CONFIG_PPC_EARLY_DEBUG_OPAL_RAW)
  73         udbg_init_debug_opal_raw();
  74 #elif defined(CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI)
  75         udbg_init_debug_opal_hvsi();
  76 #endif
  77
  78 #ifdef CONFIG_PPC_EARLY_DEBUG
  79         console_loglevel = 10;
  80
  81         register_early_udbg_console();
  82 #endif
  83 }
  84
  85 /* udbg library, used by xmon et al */
  86 void udbg_puts(const char *s)
  87 {
  88         if (udbg_putc) {
  89                 char c;
  90
  91                 if (s && *s != '\0') {
  92                         while ((c = *s++) != '\0')
  93                                 udbg_putc(c);
  94                 }
  95
  96                 if (udbg_flush)
  97                         udbg_flush();
  98         }
  99 #if 0
 100         else {
 101                 printk("%s", s);
 102         }
 103 #endif
 104 }
 105
 106 int udbg_write(const char *s, int n)
 107 {
 108         int remain = n;
 109         char c;
 110
 111         if (!udbg_putc)
 112                 return 0;
 113
 114         if (s && *s != '\0') {
 115                 while (((c = *s++) != '\0') && (remain-- > 0)) {
 116                         udbg_putc(c);
 117                 }
 118         }
 119
 120         if (udbg_flush)
 121                 udbg_flush();
 122
 123         return n - remain;
 124 }
 125
 126 #define UDBG_BUFSIZE 256
 127 void udbg_printf(const char *fmt, ...)
 128 {
 129         char buf[UDBG_BUFSIZE];
 130         va_list args;
 131
 132         va_start(args, fmt);
 133         vsnprintf(buf, UDBG_BUFSIZE, fmt, args);
 134         udbg_puts(buf);
 135         va_end(args);
 136 }
 137
 138 void __init udbg_progress(char *s, unsigned short hex)
 139 {
 140         udbg_puts(s);
 141         udbg_puts("\n");
 142 }
 143
 144 /*
 145  * Early boot console based on udbg
 146  */
 147 static void udbg_console_write(struct console *con, const char *s,
 148                 unsigned int n)
 149 {
 150         udbg_write(s, n);
 151 }
 152
 153 static struct console udbg_console = {
 154         .name   = "udbg",
 155         .write  = udbg_console_write,
 156         .flags  = CON_PRINTBUFFER | CON_ENABLED | CON_BOOT | CON_ANYTIME,
 157         .index  = 0,
 158 };
 159
 160 /*
 161  * Called by setup_system after ppc_md->probe and ppc_md->early_init.
 162  * Call it again after setting udbg_putc in ppc_md->setup_arch.
 163  */
 164 void __init register_early_udbg_console(void)
 165 {
 166         if (early_console)
 167                 return;
 168
 169         if (!udbg_putc)
 170                 return;
 171
 172         if (strstr(boot_command_line, "udbg-immortal")) {
 173                 printk(KERN_INFO "early console immortal !\n");
 174                 udbg_console.flags &= ~CON_BOOT;
 175         }
 176         early_console = &udbg_console;
 177         register_console(&udbg_console);
 178 }
 179
 180 #if 0   /* if you want to use this as a regular output console */
 181 console_initcall(register_udbg_console);
 182 #endif