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