Add PBL console support

This adds simple console support to the PBL which makes it
possible to print more complex messages in the PBL than just
strings or hex numbers. For now puts_ll is used to print the
messages, so it depends on CONFIG_DEBUG_LL which makes it
more a debugging option. However, this could be extended later
to get regular output from the PBL if desired.

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

common/Kconfig

@@ -882,6 +882,17 @@ config DEBUG_INITCALLS
 	bool "Trace initcalls"
 	help
 	  If enabled this will print initcall traces.
+
+config PBL_CONSOLE
+	depends on DEBUG_LL
+	bool "Enable console support in PBL"
+	help
+	  This enables printf/pr_* support in the PBL to get more
+	  informational output earlier during startup. Note that
+	  printf/pr_* need a valid C environment, so the binary
+	  must be running at the address it's linked at and bss must
+	  be cleared. On ARM that would be after setup_c().
+
 endmenu
 
 config HAS_DEBUG_LL

include/printk.h

@@ -22,18 +22,23 @@
 /* debugging and troubleshooting/diagnostic helpers. */
 
 #ifndef CONFIG_CONSOLE_NONE
-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)));
 #else
-static inline int pr_print(int level, const char *format, ...)
+static inline int dev_printf(int level, const struct device_d *dev, const char *format, ...)
 {
 	return 0;
 }
+#endif
 
-static inline int dev_printf(int level, const struct device_d *dev, const char *format, ...)
+#if (!defined(__PBL__) && !defined(CONFIG_CONSOLE_NONE)) || \
+	(defined(__PBL__) && defined(CONFIG_PBL_CONSOLE))
+int pr_print(int level, const char *format, ...)
+	__attribute__ ((format(__printf__, 2, 3)));
+#else
+static int pr_print(int level, const char *format, ...)
+	__attribute__ ((format(__printf__, 2, 3)));
+static inline int pr_print(int level, const char *format, ...)
 {
 	return 0;
 }

include/stdio.h

@@ -29,8 +29,6 @@ int	getc(void);
 int	console_puts(unsigned int ch, const char *s);
 void	console_flush(void);
 
-
-int	printf(const char *fmt, ...) __attribute__ ((format(__printf__, 1, 2)));
 int	vprintf(const char *fmt, va_list args);
 #else
 static inline int tstc(void)
@@ -52,13 +50,6 @@ static inline void console_putc(unsigned int ch, char c) {}
 
 static inline void console_flush(void) {}
 
-static int printf(const char *fmt, ...) __attribute__ ((format(__printf__, 1, 2)));
-static inline int printf(const char *fmt, ...)
-{
-	return 0;
-}
-
-
 static inline int vprintf(const char *fmt, va_list args)
 {
 	return 0;
@@ -74,6 +65,17 @@ static inline int ctrlc (void)
 
 #endif
 
+#if (!defined(__PBL__) && !defined(CONFIG_CONSOLE_NONE)) || \
+	(defined(__PBL__) && defined(CONFIG_PBL_CONSOLE))
+int printf(const char *fmt, ...) __attribute__ ((format(__printf__, 1, 2)));
+#else
+static int printf(const char *fmt, ...) __attribute__ ((format(__printf__, 1, 2)));
+static inline int printf(const char *fmt, ...)
+{
+	return 0;
+}
+#endif
+
 static inline int puts(const char *s)
 {
 	return console_puts(CONSOLE_STDOUT, s);

lib/Makefile

@@ -6,7 +6,9 @@ obj-y			+= display_options.o
 obj-y			+= string.o
 obj-y			+= strtox.o
 obj-y			+= vsprintf.o
+pbl-$(CONFIG_PBL_CONSOLE) += vsprintf.o
 obj-y			+= div64.o
+pbl-y			+= div64.o
 obj-y			+= misc.o
 obj-$(CONFIG_PARAMETER)	+= parameter.o
 obj-y			+= xfuncs.o

lib/vsprintf.c

@@ -175,6 +175,7 @@ static char *string(char *buf, char *end, char *s, int field_width, int precisio
 	return buf;
 }
 
+#ifndef __PBL__
 static char *symbol_string(char *buf, char *end, void *ptr, int field_width, int precision, int flags)
 {
 	unsigned long value = (unsigned long) ptr;
@@ -277,6 +278,17 @@ static char *pointer(const char *fmt, char *buf, char *end, void *ptr, int field
 	}
 	return number(buf, end, (unsigned long) ptr, 16, field_width, precision, flags);
 }
+#else
+static char *pointer(const char *fmt, char *buf, char *end, void *ptr, int field_width, int precision, int flags)
+{
+	flags |= SMALL;
+	if (field_width == -1) {
+		field_width = 2*sizeof(void *);
+		flags |= ZEROPAD;
+	}
+	return number(buf, end, (unsigned long) ptr, 16, field_width, precision, flags);
+}
+#endif
 
 /**
  * vsnprintf - Format a string and place it in a buffer

pbl/Makefile

@@ -4,3 +4,4 @@
 pbl-y += misc.o
 pbl-y += string.o
 pbl-y += decomp.o
+pbl-$(CONFIG_PBL_CONSOLE) += console.o

pbl/console.c

@@ -0,0 +1,32 @@
+#include <common.h>
+#include <debug_ll.h>
+
+int printf(const char *fmt, ...)
+{
+	va_list args;
+	uint i;
+	char printbuffer[CFG_PBSIZE];
+
+	va_start(args, fmt);
+	i = vsprintf(printbuffer, fmt, args);
+	va_end(args);
+
+	puts_ll(printbuffer);
+
+	return i;
+}
+
+int pr_print(int level, const char *fmt, ...)
+{
+	va_list args;
+	uint i;
+	char printbuffer[CFG_PBSIZE];
+
+	va_start(args, fmt);
+	i = vsprintf(printbuffer, fmt, args);
+	va_end(args);
+
+	puts_ll(printbuffer);
+
+	return i;
+}