| 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; |
| } |
| } |
| } |