The first 1M is don't care when it comes to the variables MTRRs.
Cover it as WB as a heuristic approximation; this is generally what we
want to minimize the number of registers.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
}
nr_range = x86_get_mtrr_mem_range(range, 0, extra_remove_base,
extra_remove_size);
}
nr_range = x86_get_mtrr_mem_range(range, 0, extra_remove_base,
extra_remove_size);
+ /*
+ * [0, 1M) should always be coverred by var mtrr with WB
+ * and fixed mtrrs should take effective before var mtrr for it
+ */
+ nr_range = add_range_with_merge(range, nr_range, 0,
+ (1ULL<<(20 - PAGE_SHIFT)) - 1);
+ /* sort the ranges */
+ sort(range, nr_range, sizeof(struct res_range), cmp_range, NULL);
+
range_sums = sum_ranges(range, nr_range);
printk(KERN_INFO "total RAM coverred: %ldM\n",
range_sums >> (20 - PAGE_SHIFT));
range_sums = sum_ranges(range, nr_range);
printk(KERN_INFO "total RAM coverred: %ldM\n",
range_sums >> (20 - PAGE_SHIFT));