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>
AMD recently changed the licensing of the RAM sizing code to the
GPLv2 (or at your option any later version)
Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
If the board has a high precision mico-second timer, it maked sense to use
it instead of the on-chip one
Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
Currently, the GDT is either located in FLASH or in the non-relocated
U-Boot image in RAM. Both of these locations are unsafe as those
locations can be erased during a U-Boot update. Move the GDT into the
highest available memory location and relocate U-Boot to just below it
Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
Add a parameter to the 32-bit entry to indicate if entry is from Real
Mode or not. If entry is from Real Mode, execute the destructive 'sizer'
routine to determine memory size as we are booting cold and running in
Flash. If not entering from Real Mode, we are executing a U-Boot image
from RAM and therefore the memory size is already known (and running
'sizer' will destroy the running image)
There are now two 32-bit entry points. The first is the 'in RAM' entry
point which exists at the start of the U-Boot binary image. As such,
you can load u-boot.bin in RAM and jump directly to the load address
without needing to calculate any offsets. The second entry point is
used by the real-to-protected mode switch
This patch also changes TEXT_BASE to 0x6000000 (in RAM). You can load
the resulting image at 0x6000000 and simple go 0x6000000 from the u-boot
prompt
Hopefully a later patch will completely elliminate any dependency on
TEXT_BASE like a relocatable linux kernel (perfect world)
Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
This patch allows the low-level assembler boot-strap to obtain the RAM
size without calling the destructive 'sizer' routine. This allows
boot-strapping from a U-Boot image loaded in RAM
Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
There is an error in how the assembler version of the sc520 memory size
reporting code works. As a result, it will only ever report at most the
size of one bank of RAM
Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
Shamelessly steal the Linux x86 crash handling code and shove it into
U-Boot (cool - it fits). Be sure to include suitable attribution to
Linus
Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
Wolfgang Denk
Graeme Russ
Peter Tyser