introduce runtime loglevel

With this the verbosity of barebox can be controlled during runtime
using the 'loglevel' globalvar.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

common/Kconfig

@@ -607,7 +607,7 @@ endmenu
 menu "Debugging"
 
 config COMPILE_LOGLEVEL
-	int "loglevel"
+	int "compile loglevel"
 	default 6
 	help
 	  This defines the maximum loglevel compiled into the binary. Less important
@@ -622,6 +622,22 @@ config COMPILE_LOGLEVEL
 	  6    informational (info)
 	  7    debug-level messages (debug)
 
+config DEFAULT_LOGLEVEL
+	int "default loglevel"
+	default 7
+	help
+	  This defines the default runtime loglevel. It can be changed using the
+	  global.loglevel variable. Available logelevels are:
+
+	  0    system is unusable (emerg)
+	  1    action must be taken immediately (alert)
+	  2    critical conditions (crit)
+	  3    error conditions (err)
+	  4    warning conditions (warn)
+	  5    normal but significant condition (notice)
+	  6    informational (info)
+	  7    debug-level messages (debug)
+
 config DEBUG_INFO
 	bool
 	prompt "enable debug symbols"

common/console_common.c

@@ -57,6 +57,33 @@ void console_allow_input(bool val)
 	console_input_allow = val;
 }
 
+int barebox_loglevel = CONFIG_DEFAULT_LOGLEVEL;
+
+int pr_print(int level, const char *fmt, ...)
+{
+	va_list args;
+	uint i;
+	char printbuffer[CFG_PBSIZE];
+
+	if (level > barebox_loglevel)
+		return 0;
+
+	va_start(args, fmt);
+	i = vsprintf(printbuffer, fmt, args);
+	va_end(args);
+
+	/* Print the string */
+	puts(printbuffer);
+
+	return i;
+}
+
+static int loglevel_init(void)
+{
+	return globalvar_add_simple_int("loglevel", &barebox_loglevel, "%d");
+}
+device_initcall(loglevel_init);
+
 int printf(const char *fmt, ...)
 {
 	va_list args;

drivers/base/driver.c

@@ -26,6 +26,7 @@
 #include <command.h>
 #include <driver.h>
 #include <malloc.h>
+#include <console.h>
 #include <linux/ctype.h>
 #include <errno.h>
 #include <fs.h>
@@ -370,11 +371,14 @@ const char *dev_id(const struct device_d *dev)
 	return buf;
 }
 
-int dev_printf(const struct device_d *dev, const char *format, ...)
+int dev_printf(int level, const struct device_d *dev, const char *format, ...)
 {
 	va_list args;
 	int ret = 0;
 
+	if (level > barebox_loglevel)
+		return 0;
+
 	if (dev->driver && dev->driver->name)
 		ret += printf("%s ", dev->driver->name);
 

include/console.h

@@ -57,4 +57,6 @@ extern struct list_head console_list;
 bool console_is_input_allow(void);
 void console_allow_input(bool val);
 
+extern int barebox_loglevel;
+
 #endif

include/printk.h

@@ -18,12 +18,15 @@
 
 /* debugging and troubleshooting/diagnostic helpers. */
 
-int dev_printf(const struct device_d *dev, const char *format, ...)
+int pr_print(int level, const char *format, ...)
 	__attribute__ ((format(__printf__, 2, 3)));
 
+int dev_printf(int level, const struct device_d *dev, const char *format, ...)
+	__attribute__ ((format(__printf__, 3, 4)));
+
 #define __dev_printf(level, dev, format, args...) \
 	({	\
-		(level) <= LOGLEVEL ? dev_printf((dev), (format), ##args) : 0; \
+		(level) <= LOGLEVEL ? dev_printf((level), (dev), (format), ##args) : 0; \
 	 })
 
 
@@ -46,7 +49,7 @@ int dev_printf(const struct device_d *dev, const char *format, ...)
 
 #define __pr_printk(level, format, args...) \
 	({	\
-		(level) <= LOGLEVEL ? printk((format), ##args) : 0; \
+		(level) <= LOGLEVEL ? pr_print((level), (format), ##args) : 0; \
 	 })
 
 #ifndef pr_fmt