xnu-1228.15.4.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 3d00e68f969108423ab6e95d2c66f18b2b5f90c6..84855f63ec347780278cf2eba30da6a5090a83ce 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
- * 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
@@ -20,23 +23,25 @@
  * 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
  *    i386 platform expert debugging output initialization.
  */
 #include <stdarg.h>
+#include <machine/machine_routines.h>
 #include <pexpert/pexpert.h>
 #include <kern/debug.h>
-
-/* extern references */
-extern void cnputc(char c);
+#include <kern/simple_lock.h>
+#include <i386/mp.h>
 
 /* Globals */
-void (*PE_kputc)(char c) = 0;
+void (*PE_kputc)(char c);
 
-unsigned int disableSerialOuput = TRUE;
+unsigned int disable_serial_output = TRUE;
+
+decl_simple_lock_data(static, kprintf_lock)
 
 void PE_init_kprintf(boolean_t vm_initialized)
 {
@@ -45,23 +50,71 @@ void PE_init_kprintf(boolean_t vm_initialized)
        if (PE_state.initialized == FALSE)
                panic("Platform Expert not initialized");
 
-       if (!vm_initialized)
-       {
-           if (PE_parse_boot_arg("debug", &boot_arg)) 
-               if (boot_arg & DB_KPRT) disableSerialOuput = FALSE;
-        
-        /* FIXME - route output to serial port. */
-        PE_kputc = cnputc;
-    }
+       if (!vm_initialized) {
+               simple_lock_init(&kprintf_lock, 0);
+
+               if (PE_parse_boot_argn("debug", &boot_arg, sizeof (boot_arg)))
+                       if (boot_arg & DB_KPRT)
+                               disable_serial_output = FALSE;
+
+               if (!disable_serial_output && serial_init())
+                       PE_kputc = serial_putc;
+               else
+                       PE_kputc = cnputc;
+       }
 }
 
-void kprintf(const char *fmt, ...)
+#ifdef MP_DEBUG
+static void _kprintf(const char *format, ...)
 {
-       va_list listp;
-    
-    if (!disableSerialOuput) {
-        va_start(listp, fmt);
-        _doprnt(fmt, &listp, PE_kputc, 16);
+       va_list   listp;
+
+        va_start(listp, format);
+        _doprnt(format, &listp, PE_kputc, 16);
         va_end(listp);
-    }
+}
+#define MP_DEBUG_KPRINTF(x...) _kprintf(x)
+#else  /* MP_DEBUG */
+#define MP_DEBUG_KPRINTF(x...)
+#endif /* MP_DEBUG */
+
+static int cpu_last_locked = 0;
+void kprintf(const char *fmt, ...)
+{
+       va_list   listp;
+       boolean_t state;
+
+       if (!disable_serial_output) {
+
+               /*
+                * 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);
+               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);
 }