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30 * i386 platform expert debugging output initialization.
33 #include <machine/machine_routines.h>
34 #include <pexpert/pexpert.h>
35 #include <kern/debug.h>
36 #include <kern/simple_lock.h>
37 #include <i386/machine_cpu.h>
39 #include <machine/pal_routines.h>
40 #include <i386/proc_reg.h>
41 #include <os/log_private.h>
42 #include <libkern/section_keywords.h>
43 #include <kern/processor.h>
44 #include <kern/clock.h>
45 #include <mach/clock_types.h>
47 extern uint64_t LockTimeOut
;
48 extern processor_t
current_processor(void);
51 void (*PE_kputc
)(char c
);
53 #if DEVELOPMENT || DEBUG
54 /* DEBUG kernel starts with true serial, but
55 * may later disable or switch to video
57 SECURITY_READ_ONLY_LATE(unsigned int) disable_serial_output
= FALSE
;
59 SECURITY_READ_ONLY_LATE(unsigned int) disable_serial_output
= TRUE
;
62 decl_simple_lock_data(static, kprintf_lock
);
65 PE_init_kprintf(boolean_t vm_initialized
)
67 unsigned int boot_arg
;
69 if (PE_state
.initialized
== FALSE
) {
70 panic("Platform Expert not initialized");
73 if (!vm_initialized
) {
74 unsigned int new_disable_serial_output
= TRUE
;
76 simple_lock_init(&kprintf_lock
, 0);
78 if (PE_parse_boot_argn("debug", &boot_arg
, sizeof(boot_arg
))) {
79 if (boot_arg
& DB_KPRT
) {
80 new_disable_serial_output
= FALSE
;
84 /* If we are newly enabling serial, make sure we only
85 * call pal_serial_init() if our previous state was
87 if (!new_disable_serial_output
&& (!disable_serial_output
|| pal_serial_init())) {
88 PE_kputc
= pal_serial_putc
;
93 disable_serial_output
= new_disable_serial_output
;
97 #if CONFIG_NO_KPRINTF_STRINGS
98 /* Prevent CPP from breaking the definition below */
104 _kprintf(const char *format
, ...)
108 va_start(listp
, format
);
109 _doprnt(format
, &listp
, PE_kputc
, 16);
112 #define MP_DEBUG_KPRINTF(x...) _kprintf(x)
114 #define MP_DEBUG_KPRINTF(x...)
115 #endif /* MP_DEBUG */
117 static int cpu_last_locked
= 0;
119 #define KPRINTF_LOCKWAIT_PATIENT (LockTimeOut)
120 #define KPRINTF_LOCKWAIT_IMPATIENT (LockTimeOut >> 4)
122 __attribute__((noinline
, not_tail_called
))
124 kprintf(const char *fmt
, ...)
129 boolean_t in_panic_context
= FALSE
;
130 unsigned int kprintf_lock_grabbed
;
131 void *caller
= __builtin_return_address(0);
133 if (!disable_serial_output
) {
134 boolean_t early
= FALSE
;
135 uint64_t gsbase
= rdmsr64(MSR_IA32_GS_BASE
);
136 if (gsbase
== EARLY_GSBASE_MAGIC
|| gsbase
== 0) {
139 /* If PE_kputc has not yet been initialized, don't
140 * take any locks, just dump to serial */
141 if (!PE_kputc
|| early
) {
142 va_start(listp
, fmt
);
143 va_copy(listp2
, listp
);
145 _doprnt_log(fmt
, &listp
, pal_serial_putc
, 16);
148 // If interrupts are enabled
149 if (ml_get_interrupts_enabled()) {
150 os_log_with_args(OS_LOG_DEFAULT
, OS_LOG_TYPE_DEFAULT
, fmt
, listp2
, caller
);
156 state
= ml_set_interrupts_enabled(FALSE
);
158 pal_preemption_assert();
160 in_panic_context
= processor_in_panic_context(current_processor());
162 // If current CPU is in panic context, be a little more impatient.
163 kprintf_lock_grabbed
= simple_lock_try_lock_mp_signal_safe_loop_duration(&kprintf_lock
,
164 in_panic_context
? KPRINTF_LOCKWAIT_IMPATIENT
: KPRINTF_LOCKWAIT_PATIENT
,
167 if (cpu_number() != cpu_last_locked
) {
168 MP_DEBUG_KPRINTF("[cpu%d...]\n", cpu_number());
169 cpu_last_locked
= cpu_number();
172 va_start(listp
, fmt
);
173 va_copy(listp2
, listp
);
174 _doprnt(fmt
, &listp
, PE_kputc
, 16);
177 if (kprintf_lock_grabbed
) {
178 simple_unlock(&kprintf_lock
);
181 ml_set_interrupts_enabled(state
);
183 // If interrupts are enabled
184 if (ml_get_interrupts_enabled()) {
185 os_log_with_args(OS_LOG_DEFAULT
, OS_LOG_TYPE_DEFAULT
, fmt
, listp2
, caller
);
189 if (ml_get_interrupts_enabled()) {
190 va_start(listp
, fmt
);
191 os_log_with_args(OS_LOG_DEFAULT
, OS_LOG_TYPE_DEFAULT
, fmt
, listp
, caller
);
199 extern void kprintf_break_lock(void);
201 kprintf_break_lock(void)
203 simple_lock_init(&kprintf_lock
, 0);