u-boot/board/ppmc7xx/ppmc7xx.c
Wolfgang Denk 54841ab50c 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>
2010-07-04 23:55:42 +02:00

110 lines
2.2 KiB
C

/*
* ppmc7xx.c
* ---------
*
* Main board-specific routines for Wind River PPMC 7xx/74xx board.
*
* By Richard Danter (richard.danter@windriver.com)
* Copyright (C) 2005 Wind River Systems
*/
#include <common.h>
#include <command.h>
#include <netdev.h>
/* Define some MPC107 (memory controller) registers */
#define MPC107_EUMB_GCR 0xfce41020
#define MPC107_EUMB_IACKR 0xfce600a0
/* Function prototypes */
extern void unlock_ram_in_cache( void );
extern void _start_warm(void);
/*
* initdram()
*
* This function normally initialises the (S)DRAM of the system. For this board
* the SDRAM was already initialised by board_asm_init (see init.S) so we just
* return the size of RAM.
*/
phys_size_t initdram( int board_type )
{
return CONFIG_SYS_SDRAM_SIZE;
}
/*
* after_reloc()
*
* This is called after U-Boot has been copied from Flash/ROM to RAM. It gives
* us an opportunity to do some additional setup before the rest of the system
* is initialised. We don't need to do anything, so we just call board_init_r()
* which should never return.
*/
void after_reloc( ulong dest_addr, gd_t* gd )
{
/* Jump to the main U-Boot board init code */
board_init_r( gd, dest_addr );
}
/*
* checkboard()
*
* We could do some board level checks here, such as working out what version
* it is, but for this board we simply display it's name (on the console).
*/
int checkboard( void )
{
puts( "Board: Wind River PPMC 7xx/74xx\n" );
return 0;
}
/*
* misc_init_r
*
* Used for other setup which needs to be done late in the bring-up phase.
*/
int misc_init_r( void )
{
/* Reset the EPIC and clear pending interrupts */
out32r(MPC107_EUMB_GCR, 0xa0000000);
while( in32r( MPC107_EUMB_GCR ) & 0x80000000 );
out32r( MPC107_EUMB_GCR, 0x20000000 );
while( in32r( MPC107_EUMB_IACKR ) != 0xff );
/* Enable the I-Cache */
icache_enable();
return 0;
}
/*
* do_reset()
*
* Shell command to reset the board.
*/
void do_reset( cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[] )
{
printf( "Resetting...\n" );
/* Disabe and invalidate cache */
icache_disable();
dcache_disable();
/* Jump to warm start (in RAM) */
_start_warm();
/* Should never get here */
while(1);
}
int board_eth_init(bd_t *bis)
{
return pci_eth_init(bis);
}