Make MTRR min hole alignment 64MB

[coreboot.git] / src / cpu / x86 / mtrr / mtrr.c

diff --git a/src/cpu/x86/mtrr/mtrr.c b/src/cpu/x86/mtrr/mtrr.c
index 5f5e02bbb1c9d41ea78433b998c16647c109b9f2..ed7d93bd068b30621a17261ff390df0ec321c3f3 100644 (file)
--- a/src/cpu/x86/mtrr/mtrr.c
+++ b/src/cpu/x86/mtrr/mtrr.c
@@ -265,13 +265,16 @@ static unsigned int range_to_mtrr(unsigned int reg,
                return reg;
        }
 
-       if (above4gb == 2 && type == MTRR_TYPE_WRBACK && range_sizek % 0x4000) {
+#define MIN_ALIGN 0x10000 /* 64MB */
+
+       if (above4gb == 2 && type == MTRR_TYPE_WRBACK &&
+           range_sizek > MIN_ALIGN && range_sizek % MIN_ALIGN) {
                /*
-                * If this range is not divisible by 16MB then instead
+                * If this range is not divisible then instead
                 * make a larger range and carve out an uncached hole.
                 */
                hole_startk = range_startk + range_sizek;
-               hole_sizek = 0x4000 - (range_sizek % 0x4000);
+               hole_sizek = MIN_ALIGN - (range_sizek % MIN_ALIGN);
                range_sizek += hole_sizek;
        }