xnu-1699.24.23.tar.gz

[apple/xnu.git] / pexpert / i386 / pe_kprintf.c

diff --git a/pexpert/i386/pe_kprintf.c b/pexpert/i386/pe_kprintf.c
index 4383340f09efabba52801f6ad00b9469564b02b9..6533908ebea67eecc2a767703c99990f4b389b00 100644 (file)
--- a/pexpert/i386/pe_kprintf.c
+++ b/pexpert/i386/pe_kprintf.c
@@ -1,16 +1,19 @@
 /*
 /*

- * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2000-2006 Apple Computer, Inc. All rights reserved.

  *
  *

- * @APPLE_LICENSE_HEADER_START@
- * 
- * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@

  * 
  * This file contains Original Code and/or Modifications of Original Code
  * as defined in and that are subject to the Apple Public Source License
  * Version 2.0 (the 'License'). You may not use this file except in
  * 
  * This file contains Original Code and/or Modifications of Original Code
  * as defined in and that are subject to the Apple Public Source License
  * Version 2.0 (the 'License'). You may not use this file except in

- * compliance with the License. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ * 
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.

  * 
  * The Original Code and all software distributed under the License are
  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * 
  * The Original Code and all software distributed under the License are
  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER


@@ -20,7 +23,7 @@
  * Please see the License for the specific language governing rights and
  * limitations under the License.
  * 
  * Please see the License for the specific language governing rights and
  * limitations under the License.
  * 

- * @APPLE_LICENSE_HEADER_END@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@

  */
 /*
  * file: pe_kprintf.c
  */
 /*
  * file: pe_kprintf.c


@@ -32,16 +35,19 @@
 #include <kern/debug.h>
 #include <kern/simple_lock.h>
 #include <i386/mp.h>
 #include <kern/debug.h>
 #include <kern/simple_lock.h>
 #include <i386/mp.h>

-
-/* extern references */
-extern void cnputc(char c);
-extern int  serial_init(void);
-extern void serial_putc(char c);
+#include <machine/pal_routines.h>

 
 /* Globals */
 
 /* Globals */

-void (*PE_kputc)(char c) = 0;
+void (*PE_kputc)(char c);

 
 

-unsigned int disableSerialOuput = TRUE;
+#if DEBUG
+/* DEBUG kernel starts with true serial, but
+ * may later disable or switch to video
+ * console */
+unsigned int disable_serial_output = FALSE;
+#else
+unsigned int disable_serial_output = TRUE;
+#endif

 
 decl_simple_lock_data(static, kprintf_lock)
 
 
 decl_simple_lock_data(static, kprintf_lock)
 


@@ -52,20 +58,32 @@ void PE_init_kprintf(boolean_t vm_initialized)
        if (PE_state.initialized == FALSE)
                panic("Platform Expert not initialized");
 
        if (PE_state.initialized == FALSE)
                panic("Platform Expert not initialized");
 

-       if (!vm_initialized)
-       {
-        simple_lock_init(&kprintf_lock, 0);
+       if (!vm_initialized) {
+               unsigned int new_disable_serial_output = TRUE;
+
+               simple_lock_init(&kprintf_lock, 0);
+
+               if (PE_parse_boot_argn("debug", &boot_arg, sizeof (boot_arg)))
+                       if (boot_arg & DB_KPRT)
+                               new_disable_serial_output = FALSE;

 
 

-           if (PE_parse_boot_arg("debug", &boot_arg)) 
-               if (boot_arg & DB_KPRT) disableSerialOuput = FALSE;
+               /* If we are newly enabling serial, make sure we only
+                * call pal_serial_init() if our previous state was
+                * not enabled */
+               if (!new_disable_serial_output && (!disable_serial_output || pal_serial_init()))
+                       PE_kputc = pal_serial_putc;
+               else
+                       PE_kputc = cnputc;

 
 

-        if (!disableSerialOuput && serial_init())
-            PE_kputc = serial_putc;
-        else
-            PE_kputc = cnputc;
-    }
+               disable_serial_output = new_disable_serial_output;
+       }

 }
 
 }
 

+#if CONFIG_NO_KPRINTF_STRINGS
+/* Prevent CPP from breaking the definition below */
+#undef kprintf
+#endif
+

 #ifdef MP_DEBUG
 static void _kprintf(const char *format, ...)
 {
 #ifdef MP_DEBUG
 static void _kprintf(const char *format, ...)
 {


@@ -84,22 +102,51 @@ static int cpu_last_locked = 0;
 void kprintf(const char *fmt, ...)
 {
        va_list   listp;
 void kprintf(const char *fmt, ...)
 {
        va_list   listp;

-    boolean_t state;
-    
-    if (!disableSerialOuput) {
-        state = ml_set_interrupts_enabled(FALSE);
-        simple_lock(&kprintf_lock);
-
-       if (cpu_number() != cpu_last_locked) {
-           MP_DEBUG_KPRINTF("[cpu%d...]\n", cpu_number());
-           cpu_last_locked = cpu_number();
-       }
+       boolean_t state;

 
 

-        va_start(listp, fmt);
-        _doprnt(fmt, &listp, PE_kputc, 16);
-        va_end(listp);
+       if (!disable_serial_output) {
+
+               /* If PE_kputc has not yet been initialized, don't
+                * take any locks, just dump to serial */
+               if (!PE_kputc) {
+                       va_start(listp, fmt);
+                       _doprnt(fmt, &listp, pal_serial_putc, 16);
+                       va_end(listp);
+                       return;
+               }

 
 

-        simple_unlock(&kprintf_lock);
-        ml_set_interrupts_enabled(state);
-    }
+               /*
+                * Spin to get kprintf lock but re-enable interrupts while
+                * failing.
+                * This allows interrupts to be handled while waiting but
+                * interrupts are disabled once we have the lock.
+                */
+               state = ml_set_interrupts_enabled(FALSE);
+
+               pal_preemption_assert();
+
+               while (!simple_lock_try(&kprintf_lock)) {
+                       ml_set_interrupts_enabled(state);
+                       ml_set_interrupts_enabled(FALSE);
+               }
+
+               if (cpu_number() != cpu_last_locked) {
+                       MP_DEBUG_KPRINTF("[cpu%d...]\n", cpu_number());
+                       cpu_last_locked = cpu_number();
+               }
+
+               va_start(listp, fmt);
+               _doprnt(fmt, &listp, PE_kputc, 16);
+               va_end(listp);
+
+               simple_unlock(&kprintf_lock);
+               ml_set_interrupts_enabled(state);
+       }
+}
+
+extern void kprintf_break_lock(void);
+void
+kprintf_break_lock(void)
+{
+       simple_lock_init(&kprintf_lock, 0);

 }
 }