Make getenv() work before relocation.

So far, getenv() would work before relocation is most cases, even
though it was not intended to be used that way.  When switching to a
hash table based implementation, this would break a number of boards.

For convenience, we make getenv() check if it's running before
relocation and, if so, use getenv_f() internally.

Note that this is limited to simple cases, as we use a small static
buffer (32 bytes) in the global data for this purpose.

For this reason, it is also not a good idea to convert all current
uses of getenv_f() into getenv() - some of the existing use cases need
to be able to deal with longer variable values, so getenv_f() is still
needed and recommended for use before relocation.

Signed-off-by: Wolfgang Denk <wd@denx.de>

arch/arm/include/asm/global_data.h

@@ -1,5 +1,5 @@
 /*
- * (C) Copyright 2002
+ * (C) Copyright 2002-2010
  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  *
  * See file CREDITS for list of people who contributed to this
@@ -47,13 +47,8 @@ typedef	struct	global_data {
 #ifdef CONFIG_FSL_ESDHC
 	unsigned long	sdhc_clk;
 #endif
-#if 0
-	unsigned long	cpu_clk;	/* CPU clock in Hz!		*/
-	unsigned long	bus_clk;
-	phys_size_t	ram_size;	/* RAM size */
-	unsigned long	reset_status;	/* reset status register at boot */
-#endif
 	void		**jt;		/* jump table */
+	char		env_buf[32];	/* buffer for getenv() before reloc. */
 } gd_t;
 
 /*

arch/avr32/include/asm/global_data.h

@@ -46,6 +46,7 @@ typedef	struct	global_data {
 	void		*fb_base;	/* framebuffer address */
 #endif
 	void		**jt;		/* jump table */
+	char		env_buf[32];	/* buffer for getenv() before reloc. */
 } gd_t;
 
 /*

arch/blackfin/include/asm/global_data.h

@@ -3,7 +3,7 @@
  *
  * Copyright (c) 2005-2007 Analog Devices Inc.
  *
- * (C) Copyright 2000-2004
+ * (C) Copyright 2000-2010
  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  *
  * See file CREDITS for list of people who contributed to this
@@ -54,6 +54,7 @@ typedef struct global_data {
 #endif
 
 	void	**jt;			/* jump table */
+	char	env_buf[32];		/* buffer for getenv() before reloc. */
 } gd_t;
 
 /*

arch/i386/include/asm/global_data.h

@@ -1,5 +1,5 @@
 /*
- * (C) Copyright 2002
+ * (C) Copyright 2002-2010
  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  *
  * See file CREDITS for list of people who contributed to this
@@ -46,6 +46,7 @@ typedef	struct {
 	phys_size_t	ram_size;	/* RAM size */
 	unsigned long	reset_status;	/* reset status register at boot */
 	void		**jt;		/* jump table */
+	char		env_buf[32];	/* buffer for getenv() before reloc. */
 } gd_t;
 
 /*

arch/m68k/include/asm/global_data.h

@@ -1,5 +1,5 @@
 /*
- * (C) Copyright 2002 - 2003
+ * (C) Copyright 2002 - 2010
  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  *
  * See file CREDITS for list of people who contributed to this
@@ -64,6 +64,7 @@ typedef	struct	global_data {
 	unsigned long	board_type;
 #endif
 	void		**jt;		/* Standalone app jump table */
+	char		env_buf[32];	/* buffer for getenv() before reloc. */
 } gd_t;
 
 /*

arch/microblaze/include/asm/global_data.h

@@ -43,6 +43,7 @@ typedef	struct	global_data {
 	unsigned long	env_valid;	/* Checksum of Environment valid? */
 	unsigned long	fb_base;	/* base address of frame buffer */
 	void		**jt;		/* jump table */
+	char		env_buf[32];	/* buffer for getenv() before reloc. */
 } gd_t;
 
 /*

arch/mips/include/asm/global_data.h

@@ -1,5 +1,5 @@
 /*
- * (C) Copyright 2002-2003
+ * (C) Copyright 2002-2010
  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  *
  * See file CREDITS for list of people who contributed to this
@@ -46,6 +46,7 @@ typedef	struct	global_data {
 	unsigned long	env_addr;	/* Address  of Environment struct */
 	unsigned long	env_valid;	/* Checksum of Environment valid? */
 	void		**jt;		/* jump table */
+	char		env_buf[32];	/* buffer for getenv() before reloc. */
 } gd_t;
 
 /*

arch/nios2/include/asm/global_data.h

@@ -37,6 +37,7 @@ typedef	struct	global_data {
 	unsigned long	post_init_f_time; /* When post_init_f started */
 #endif
 	void		**jt;		/* Standalone app jump table */
+	char		env_buf[32];	/* buffer for getenv() before reloc. */
 } gd_t;
 
 /* flags */

arch/powerpc/include/asm/global_data.h

@@ -1,5 +1,5 @@
 /*
- * (C) Copyright 2002
+ * (C) Copyright 2002-2010
  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  *
  * See file CREDITS for list of people who contributed to this
@@ -176,6 +176,7 @@ typedef	struct	global_data {
 	unsigned long long wdt_last;	/* trace watch-dog triggering rate */
 #endif
 	void		**jt;		/* jump table */
+	char		env_buf[32];	/* buffer for getenv() before reloc. */
 } gd_t;
 
 /*

arch/sh/include/asm/global_data.h

@@ -1,5 +1,5 @@
 /*
- * (C) Copyright 2002
+ * (C) Copyright 2002-2010
  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  *
  * (C) Copyright 2007
@@ -38,6 +38,7 @@ typedef	struct global_data
 	unsigned long	env_addr;	/* Address  of Environment struct */
 	unsigned long	env_valid;	/* Checksum of Environment valid */
 	void		**jt;		/* Standalone app jump table */
+	char		env_buf[32];	/* buffer for getenv() before reloc. */
 } gd_t;
 
 #define	GD_FLG_RELOC	0x00001		/* Code was relocated to RAM		*/

arch/sparc/include/asm/global_data.h

@@ -1,5 +1,5 @@
 /*
- * (C) Copyright 2002
+ * (C) Copyright 2002-2010
  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  *
  * (C) Copyright 2007
@@ -71,6 +71,7 @@ typedef struct global_data {
 	unsigned long kbd_status;
 #endif
 	void	**jt;			/* jump table */
+	char	env_buf[32];		/* buffer for getenv() before reloc. */
 } gd_t;
 
 /*

common/cmd_nvedit.c

@@ -511,6 +511,7 @@ int do_editenv(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 
 char *getenv (char *name)
 {
+	if (gd->flags & GD_FLG_RELOC) {	/* full C runtime after reloc */
 		int i, nxt;
 
 		WATCHDOG_RESET();
@@ -531,6 +532,12 @@ char *getenv (char *name)
 		return (NULL);
 	}
 
+	/* restricted C runtime before reloc */
+
+	return ((getenv_f(name,gd->env_buf,sizeof(gd->env_buf)) > 0) ?
+		gd->env_buf : NULL);
+}
+
 int getenv_f(char *name, char *buf, unsigned len)
 {
 	int i, nxt;