39 lines
827 B
C
39 lines
827 B
C
|
static void spd_set_drb(void)
|
||
|
|
{
|
||
|
|
/*
|
||
|
|
* Effects: Uses serial presence detect to set the
|
||
|
|
* DRB registers which holds the ending memory address assigned
|
||
|
|
* to each DIMM.
|
||
|
|
*/
|
||
|
|
unsigned end_of_memory;
|
||
|
|
unsigned device;
|
||
|
|
|
||
|
|
end_of_memory = 0; /* in multiples of 8MiB */
|
||
|
|
device = 0x50;
|
||
|
|
while (device <= 0x53) {
|
||
|
|
unsigned side1_bits, side2_bits;
|
||
|
|
int byte, byte2;
|
||
|
|
|
||
|
|
side1_bits = side2_bits = -1;
|
||
|
|
|
||
|
|
/* rows */
|
||
|
|
byte = -1;
|
||
|
|
if (1) {
|
||
|
|
/* now I have the ram size in bits as a power of two (less 1) */
|
||
|
|
/* Make it mulitples of 8MB */
|
||
|
|
side1_bits -= 25;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Compute the end address for the DRB register */
|
||
|
|
/* Only process dimms < 2GB (2^8 * 8MB) */
|
||
|
|
if (1) {
|
||
|
|
end_of_memory += side1_bits;
|
||
|
|
}
|
||
|
|
__builtin_outl(end_of_memory, 0x1234);
|
||
|
|
|
||
|
|
if (1) {
|
||
|
|
end_of_memory += side2_bits;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|