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Fix Apollo DRB wraparound

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This commit is contained in:
RichardG867
2020-06-26 22:15:21 -03:00
parent 3a9408eadc
commit 012f01cc9f
1 changed files with 14 additions and 7 deletions
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21
src/mem/spd.c
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@@ -413,7 +413,7 @@ spd_write_drbs(uint8_t *regs, uint8_t reg_min, uint8_t reg_max, uint8_t drb_unit
/* Special case for VIA Apollo Pro family, which jumps from 5F to 56. */
if (reg_max < reg_min) {
apollo = reg_max;
reg_max = reg_min + 8;
reg_max = reg_min + 7;
}
/* No SPD: split SIMMs into pairs as if they were "DIMM"s. */
@@ -443,14 +443,21 @@ spd_write_drbs(uint8_t *regs, uint8_t reg_min, uint8_t reg_max, uint8_t drb_unit
/* Determine the DRB register to write. */
drb = reg_min + row;
if ((apollo) && ((drb & 0xf) < 0x8))
drb = apollo + (drb & 0xf);
/* Write DRB register, adding the previous DRB's value.
This will intentionally overflow on 440GX with 2 GB. */
regs[drb] = ((row > 0) ? regs[drb - 1] : 0);
spd_log("want drb reg %02x", drb);
if ((apollo) && ((drb & 0xf) < 0xa))
drb = apollo + (drb & 0xf);
spd_log(" got %02x\n", drb);
/* Write DRB register, adding the previous DRB's value. */
if (row == 0)
regs[drb] = 0;
else if ((apollo) && (drb == apollo))
regs[drb] = regs[drb | 0xf]; /* 5F comes before 56 */
else
regs[drb] = regs[drb - 1];
if (size)
regs[drb] += (size / drb_unit);
regs[drb] += (size / drb_unit); /* this will intentionally overflow on 440GX with 2 GB */
spd_log("DRB[%d] = %d MB (%02Xh raw)\n", row, size, regs[drb]);
}
}