Make sure that argv[] argument pointers are not modified.

The hush shell dynamically allocates (and re-allocates) memory for the
argument strings in the "char *argv[]" argument vector passed to
commands.  Any code that modifies these pointers will cause serious
corruption of the malloc data structures and crash U-Boot, so make
sure the compiler can check that no such modifications are being done
by changing the code into "char * const argv[]".

This modification is the result of debugging a strange crash caused
after adding a new command, which used the following argument
processing code which has been working perfectly fine in all Unix
systems since version 6 - but not so in U-Boot:

int main (int argc, char **argv)
{
	while (--argc > 0 && **++argv == '-') {
/* ====> */	while (*++*argv) {
			switch (**argv) {
			case 'd':
				debug++;
				break;
			...
			default:
				usage ();
			}
		}
	}
	...
}

The line marked "====>" will corrupt the malloc data structures and
usually cause U-Boot to crash when the next command gets executed by
the shell.  With the modification, the compiler will prevent this with
an
	error: increment of read-only location '*argv'

N.B.: The code above can be trivially rewritten like this:

	while (--argc > 0 && **++argv == '-') {
		char *arg = *argv;
		while (*++arg) {
			switch (*arg) {
			...

Signed-off-by: Wolfgang Denk <wd@denx.de>
Acked-by: Mike Frysinger <vapier@gentoo.org>
diff --git a/board/amcc/acadia/cmd_acadia.c b/board/amcc/acadia/cmd_acadia.c
index c427f9e..86f86e2 100644
--- a/board/amcc/acadia/cmd_acadia.c
+++ b/board/amcc/acadia/cmd_acadia.c
@@ -38,7 +38,7 @@
 	0x00, 0x00, 0x00, 0x00
 };
 
-static int do_bootstrap(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
+static int do_bootstrap(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
 	u8 chip;
 	u8 *buf;
diff --git a/board/amcc/luan/luan.c b/board/amcc/luan/luan.c
index 4e12e9a..c0368c0 100644
--- a/board/amcc/luan/luan.c
+++ b/board/amcc/luan/luan.c
@@ -207,7 +207,7 @@
  *  int do_l2cache()
  *
  ************************************************************************/
-int do_l2cache( cmd_tbl_t *cmdtp, int flag, int argc, char *argv[] )
+int do_l2cache( cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[] )
 {
 	switch (argc) {
 	case 2:			/* on / off	*/
diff --git a/board/amcc/makalu/cmd_pll.c b/board/amcc/makalu/cmd_pll.c
index 9bae67e..3c0dc5f 100644
--- a/board/amcc/makalu/cmd_pll.c
+++ b/board/amcc/makalu/cmd_pll.c
@@ -178,7 +178,7 @@
 }
 
 int
-do_pll_alter (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
+do_pll_alter (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
 	char c = '\0';
 	pll_freq_t pll_freq;
diff --git a/board/amcc/taihu/lcd.c b/board/amcc/taihu/lcd.c
index c3dc983..595dee3 100644
--- a/board/amcc/taihu/lcd.c
+++ b/board/amcc/taihu/lcd.c
@@ -129,7 +129,7 @@
 	return 0;
 }
 
-static int do_lcd_clear (cmd_tbl_t * cmdtp, int flag, int argc, char *argv[])
+static int do_lcd_clear (cmd_tbl_t * cmdtp, int flag, int argc, char * const argv[])
 {
 	out_8((u8 *) LCD_CMD_ADDR, 0x01);
 	udelay(2000);
@@ -137,7 +137,7 @@
 	return 0;
 }
 
-static int do_lcd_puts (cmd_tbl_t * cmdtp, int flag, int argc, char *argv[])
+static int do_lcd_puts (cmd_tbl_t * cmdtp, int flag, int argc, char * const argv[])
 {
 	if (argc < 2) {
 		cmd_usage(cmdtp);
@@ -148,7 +148,7 @@
 	return 0;
 }
 
-static int do_lcd_putc (cmd_tbl_t * cmdtp, int flag, int argc, char *argv[])
+static int do_lcd_putc (cmd_tbl_t * cmdtp, int flag, int argc, char * const argv[])
 {
 	if (argc < 2) {
 		cmd_usage(cmdtp);
@@ -159,7 +159,7 @@
 	return 0;
 }
 
-static int do_lcd_cur (cmd_tbl_t * cmdtp, int flag, int argc, char *argv[])
+static int do_lcd_cur (cmd_tbl_t * cmdtp, int flag, int argc, char * const argv[])
 {
 	ulong count;
 	ulong dir;
diff --git a/board/amcc/taihu/taihu.c b/board/amcc/taihu/taihu.c
index be381d6..1682cf7 100644
--- a/board/amcc/taihu/taihu.c
+++ b/board/amcc/taihu/taihu.c
@@ -78,7 +78,7 @@
 	return 0;
 }
 
-static int do_sw_stat(cmd_tbl_t* cmd_tp, int flags, int argc, char *argv[])
+static int do_sw_stat(cmd_tbl_t* cmd_tp, int flags, int argc, char * const argv[])
 {
 	char stat;
 	int i;
@@ -97,7 +97,7 @@
 	""
 );
 
-static int do_led_ctl(cmd_tbl_t* cmd_tp, int flags, int argc, char *argv[])
+static int do_led_ctl(cmd_tbl_t* cmd_tp, int flags, int argc, char * const argv[])
 {
 	int led_no;
 
diff --git a/board/amcc/taihu/update.c b/board/amcc/taihu/update.c
index f9c31b3..b87eac4 100644
--- a/board/amcc/taihu/update.c
+++ b/board/amcc/taihu/update.c
@@ -98,7 +98,7 @@
 	0x00
 };
 
-static int update_boot_eeprom(cmd_tbl_t* cmdtp, int flag, int argc, char *argv[])
+static int update_boot_eeprom(cmd_tbl_t* cmdtp, int flag, int argc, char * const argv[])
 {
 	ulong len = 0x20;
 	uchar chip = CONFIG_SYS_I2C_EEPROM_ADDR;
diff --git a/board/amcc/taishan/lcd.c b/board/amcc/taishan/lcd.c
index d432cc3..6a049df 100644
--- a/board/amcc/taishan/lcd.c
+++ b/board/amcc/taishan/lcd.c
@@ -152,19 +152,19 @@
 	return 0;
 }
 
-static int do_lcd_test(cmd_tbl_t * cmdtp, int flag, int argc, char *argv[])
+static int do_lcd_test(cmd_tbl_t * cmdtp, int flag, int argc, char * const argv[])
 {
 	lcd_init();
 	return 0;
 }
 
-static int do_lcd_clear(cmd_tbl_t * cmdtp, int flag, int argc, char *argv[])
+static int do_lcd_clear(cmd_tbl_t * cmdtp, int flag, int argc, char * const argv[])
 {
 	*LCD_CMD_ADDR = 0x01;
 	mdelay(LCD_DELAY_NORMAL_MS);
 	return 0;
 }
-static int do_lcd_puts(cmd_tbl_t * cmdtp, int flag, int argc, char *argv[])
+static int do_lcd_puts(cmd_tbl_t * cmdtp, int flag, int argc, char * const argv[])
 {
 	if (argc < 2) {
 		cmd_usage(cmdtp);
@@ -173,7 +173,7 @@
 	lcd_puts(argv[1]);
 	return 0;
 }
-static int do_lcd_putc(cmd_tbl_t * cmdtp, int flag, int argc, char *argv[])
+static int do_lcd_putc(cmd_tbl_t * cmdtp, int flag, int argc, char * const argv[])
 {
 	if (argc < 2) {
 		cmd_usage(cmdtp);
@@ -182,7 +182,7 @@
 	lcd_putc((char)argv[1][0]);
 	return 0;
 }
-static int do_lcd_cur(cmd_tbl_t * cmdtp, int flag, int argc, char *argv[])
+static int do_lcd_cur(cmd_tbl_t * cmdtp, int flag, int argc, char * const argv[])
 {
 	ulong count;
 	ulong dir;
@@ -356,7 +356,7 @@
 }
 #endif	/* 0 - test only */
 
-static int do_led_test_off(cmd_tbl_t * cmdtp, int flag, int argc, char *argv[])
+static int do_led_test_off(cmd_tbl_t * cmdtp, int flag, int argc, char * const argv[])
 {
 	volatile unsigned int *GpioOr =
 		(volatile unsigned int *)(CONFIG_SYS_PERIPHERAL_BASE + 0x700);
@@ -364,7 +364,7 @@
 	return 0;
 }
 
-static int do_led_test_on(cmd_tbl_t * cmdtp, int flag, int argc, char *argv[])
+static int do_led_test_on(cmd_tbl_t * cmdtp, int flag, int argc, char * const argv[])
 {
 	volatile unsigned int *GpioOr =
 		(volatile unsigned int *)(CONFIG_SYS_PERIPHERAL_BASE + 0x700);
diff --git a/board/amcc/taishan/showinfo.c b/board/amcc/taishan/showinfo.c
index a9a80e5..587fe74 100644
--- a/board/amcc/taishan/showinfo.c
+++ b/board/amcc/taishan/showinfo.c
@@ -161,7 +161,7 @@
 	printf("PCIL0_XSTS              = %#010lx\n", in32r(PCIL0_STS));
 }
 
-int do_show_xbridge_info(cmd_tbl_t * cmdtp, int flag, int argc, char *argv[])
+int do_show_xbridge_info(cmd_tbl_t * cmdtp, int flag, int argc, char * const argv[])
 {
 	show_xbridge_info();
 	return 0;
@@ -215,7 +215,7 @@
 }
 
 int do_show_pcix_device_info(cmd_tbl_t * cmdtp, int flag, int argc,
-			     char *argv[])
+			     char * const argv[])
 {
 	show_pcix_device_info();
 	return 0;
@@ -226,7 +226,7 @@
 
 extern void show_reset_reg(void);
 
-int do_show_reset_reg_info(cmd_tbl_t * cmdtp, int flag, int argc, char *argv[])
+int do_show_reset_reg_info(cmd_tbl_t * cmdtp, int flag, int argc, char * const argv[])
 {
 	show_reset_reg();
 	return 0;
diff --git a/board/amcc/taishan/update.c b/board/amcc/taishan/update.c
index aab3a65..3f063a0 100644
--- a/board/amcc/taishan/update.c
+++ b/board/amcc/taishan/update.c
@@ -68,7 +68,7 @@
 	return 0;
 }
 
-int do_update_boot_eeprom(cmd_tbl_t * cmdtp, int flag, int argc, char *argv[])
+int do_update_boot_eeprom(cmd_tbl_t * cmdtp, int flag, int argc, char * const argv[])
 {
 	return update_boot_eeprom();
 }
diff --git a/board/amcc/yucca/cmd_yucca.c b/board/amcc/yucca/cmd_yucca.c
index ed6daa3..cde13e4 100644
--- a/board/amcc/yucca/cmd_yucca.c
+++ b/board/amcc/yucca/cmd_yucca.c
@@ -31,10 +31,10 @@
 
 extern void print_evb440spe_info(void);
 static int setBootStrapClock(cmd_tbl_t *cmdtp, int incrflag,
-		int flag, int argc, char *argv[]);
+		int flag, int argc, char * const argv[]);
 
 /* ------------------------------------------------------------------------- */
-int do_evb440spe(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
+int do_evb440spe(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
 	return setBootStrapClock (cmdtp, 1, flag, argc, argv);
 }
@@ -46,7 +46,7 @@
  *	evb440spe wrclk prom0,prom1
  */
 static int setBootStrapClock(cmd_tbl_t *cmdtp, int incrflag, int flag,
-		int argc, char *argv[])
+		int argc, char * const argv[])
 {
 	uchar	chip;
 	ulong	data;