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
20void (*udbg_putc)(char c);
21void (*udbg_flush)(void);
22int (*udbg_getc)(void);
23int (*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 */
29void __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_PAS_REALMODE)
50	udbg_init_pas_realmode();
51#elif defined(CONFIG_PPC_EARLY_DEBUG_BOOTX)
52	udbg_init_btext();
53#elif defined(CONFIG_PPC_EARLY_DEBUG_44x)
54	/* PPC44x debug */
55	udbg_init_44x_as1();
56#elif defined(CONFIG_PPC_EARLY_DEBUG_40x)
57	/* PPC40x debug */
58	udbg_init_40x_realmode();
59#elif defined(CONFIG_PPC_EARLY_DEBUG_CPM)
60	udbg_init_cpm();
61#elif defined(CONFIG_PPC_EARLY_DEBUG_USBGECKO)
62	udbg_init_usbgecko();
63#elif defined(CONFIG_PPC_EARLY_DEBUG_MEMCONS)
64	/* In memory console */
65	udbg_init_memcons();
66#elif defined(CONFIG_PPC_EARLY_DEBUG_EHV_BC)
67	udbg_init_ehv_bc();
68#elif defined(CONFIG_PPC_EARLY_DEBUG_PS3GELIC)
69	udbg_init_ps3gelic();
70#elif defined(CONFIG_PPC_EARLY_DEBUG_OPAL_RAW)
71	udbg_init_debug_opal_raw();
72#elif defined(CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI)
73	udbg_init_debug_opal_hvsi();
74#endif
75
76#ifdef CONFIG_PPC_EARLY_DEBUG
77	console_loglevel = 10;
78
79	register_early_udbg_console();
80#endif
81}
82
83/* udbg library, used by xmon et al */
84void udbg_puts(const char *s)
85{
86	if (udbg_putc) {
87		char c;
88
89		if (s && *s != '\0') {
90			while ((c = *s++) != '\0')
91				udbg_putc(c);
92		}
93
94		if (udbg_flush)
95			udbg_flush();
96	}
97#if 0
98	else {
99		printk("%s", s);
100	}
101#endif
102}
103
104int udbg_write(const char *s, int n)
105{
106	int remain = n;
107	char c;
108
109	if (!udbg_putc)
110		return 0;
111
112	if (s && *s != '\0') {
113		while (((c = *s++) != '\0') && (remain-- > 0)) {
114			udbg_putc(c);
115		}
116	}
117
118	if (udbg_flush)
119		udbg_flush();
120
121	return n - remain;
122}
123
124#define UDBG_BUFSIZE 256
125void udbg_printf(const char *fmt, ...)
126{
127	char buf[UDBG_BUFSIZE];
128	va_list args;
129
130	va_start(args, fmt);
131	vsnprintf(buf, UDBG_BUFSIZE, fmt, args);
132	udbg_puts(buf);
133	va_end(args);
134}
135
136void __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 */
145static void udbg_console_write(struct console *con, const char *s,
146		unsigned int n)
147{
148	udbg_write(s, n);
149}
150
151static 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 */
162void __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 */
179console_initcall(register_udbg_console);
180#endif
181