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 */
udbg_early_init(void)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 */
udbg_puts(const char * s)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
udbg_write(const char * s,int n)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
udbg_printf(const char * fmt,...)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
udbg_progress(char * s,unsigned short hex)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 */
udbg_console_write(struct console * con,const char * s,unsigned int n)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 */
register_early_udbg_console(void)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