On 2/23/23 4:32 AM, Juergen Gross wrote:
+
+ for (reg = 0; reg < MTRR_MAX_VAR_RANGES; reg++) {
+ op.u.read_memtype.reg = reg;
+ if (HYPERVISOR_platform_op(&op))
+ break;
If we fail on the first iteration, do we still want to mark MTRRs are
enabled/set in mtrr_overwrite_state()?
-boris
+
+ /*
+ * Only called in dom0, which has all RAM PFNs mapped at
+ * RAM MFNs, and all PCI space etc. is identity mapped.
+ * This means we can treat MFN == PFN regarding MTTR settings.
+ */
+ var[reg].base_lo = op.u.read_memtype.type;
+ var[reg].base_lo |= op.u.read_memtype.mfn << PAGE_SHIFT;
+ var[reg].base_hi = op.u.read_memtype.mfn >> (32 - PAGE_SHIFT);
+ mask = ~((op.u.read_memtype.nr_mfns << PAGE_SHIFT) - 1);
+ mask &= (1UL << width) - 1;
+ if (mask)
+ mask |= 1 << 11;
+ var[reg].mask_lo = mask;
+ var[reg].mask_hi = mask >> 32;
+ }
+
+ mtrr_overwrite_state(var, reg, MTRR_TYPE_UNCACHABLE);
+#endif
+}
