1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * polling mode stateless debugging stuff, originally for NS16550 Serial Ports
5 * c 2001 PPC 64 Team, IBM Corp
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>
16 void (*udbg_putc)(char c);
17 void (*udbg_flush)(void);
18 int (*udbg_getc)(void);
19 int (*udbg_getc_poll)(void);
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.
25 void __init udbg_early_init(void)
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_MAPLE)
43 /* Maple real mode debug */
44 udbg_init_maple_realmode();
45 #elif defined(CONFIG_PPC_EARLY_DEBUG_PAS_REALMODE)
46 udbg_init_pas_realmode();
47 #elif defined(CONFIG_PPC_EARLY_DEBUG_BOOTX)
49 #elif defined(CONFIG_PPC_EARLY_DEBUG_44x)
52 #elif defined(CONFIG_PPC_EARLY_DEBUG_40x)
54 udbg_init_40x_realmode();
55 #elif defined(CONFIG_PPC_EARLY_DEBUG_CPM)
57 #elif defined(CONFIG_PPC_EARLY_DEBUG_USBGECKO)
59 #elif defined(CONFIG_PPC_EARLY_DEBUG_MEMCONS)
60 /* In memory console */
62 #elif defined(CONFIG_PPC_EARLY_DEBUG_EHV_BC)
64 #elif defined(CONFIG_PPC_EARLY_DEBUG_PS3GELIC)
66 #elif defined(CONFIG_PPC_EARLY_DEBUG_OPAL_RAW)
67 udbg_init_debug_opal_raw();
68 #elif defined(CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI)
69 udbg_init_debug_opal_hvsi();
70 #elif defined(CONFIG_PPC_EARLY_DEBUG_16550)
71 udbg_init_debug_16550();
74 #ifdef CONFIG_PPC_EARLY_DEBUG
75 console_loglevel = CONSOLE_LOGLEVEL_DEBUG;
77 register_early_udbg_console();
81 /* udbg library, used by xmon et al */
82 void udbg_puts(const char *s)
87 if (s && *s != '\0') {
88 while ((c = *s++) != '\0')
102 int udbg_write(const char *s, int n)
110 if (s && *s != '\0') {
111 while (((c = *s++) != '\0') && (remain-- > 0)) {
122 #define UDBG_BUFSIZE 256
123 void udbg_printf(const char *fmt, ...)
126 char buf[UDBG_BUFSIZE];
130 vsnprintf(buf, UDBG_BUFSIZE, fmt, args);
136 void __init udbg_progress(char *s, unsigned short hex)
143 * Early boot console based on udbg
145 static void udbg_console_write(struct console *con, const char *s,
151 static struct console udbg_console = {
153 .write = udbg_console_write,
154 .flags = CON_PRINTBUFFER | CON_ENABLED | CON_BOOT | CON_ANYTIME,
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.
162 void __init register_early_udbg_console(void)
170 if (strstr(boot_command_line, "udbg-immortal")) {
171 printk(KERN_INFO "early console immortal !\n");
172 udbg_console.flags &= ~CON_BOOT;
174 early_console = &udbg_console;
175 register_console(&udbg_console);
178 #if 0 /* if you want to use this as a regular output console */
179 console_initcall(register_udbg_console);