- int arch_phys_wc_add(unsigned long base, unsigned long size);
- Physical base address
- Size of region
If PAT is available, this does nothing. If PAT is unavailable, it attempts to add a WC MTRR covering size bytes starting at base and logs an error if this fails.
Drivers must store the return value to pass to mtrr_del_wc_if_needed, but drivers should not try to interpret that return value.