cpu/x86/mtrr: Use single code path with/without holes

cpu/x86/mtrr: Use single code path with/without holes

Now that calc_var_mtrrs_with_hole() always chooses the optimal
allocation, there is no need for calc_var_mtrrs_without_hole()
any more. Drop it and all the logic to decide which one to call.

Tests performed compared to "upstream" (before "cpu/x86/mtrr:
Optimize hole carving strategy") on a Lenovo/X200s with 48MiB
GFX stolen memory.

2GiB total RAM: 3 MTRRs saved

MTRR: Physical address space:
0x0000000000000000 - 0x00000000000a0000 size 0x000a0000 type 6
0x00000000000a0000 - 0x00000000000c0000 size 0x00020000 type 0
0x00000000000c0000 - 0x000000007ac00000 size 0x7ab40000 type 6
0x000000007ac00000 - 0x00000000d0000000 size 0x55400000 type 0
0x00000000d0000000 - 0x00000000e0000000 size 0x10000000 type 1
0x00000000e0000000 - 0x0000000100000000 size 0x20000000 type 0

upstream:
MTRR: Removing WRCOMB type. WB/UC MTRR counts: 7/8 > 6.
MTRR: default type WB/UC MTRR counts: 4/7.
MTRR: WB selected as default type.
MTRR: 0 base 0x000000007ac00000 mask 0x0000000fffc00000 type 0
MTRR: 1 base 0x000000007b000000 mask 0x0000000fff000000 type 0
MTRR: 2 base 0x000000007c000000 mask 0x0000000ffc000000 type 0
MTRR: 3 base 0x0000000080000000 mask 0x0000000f80000000 type 0

patched:
MTRR: default type WB/UC MTRR counts: 7/5.
MTRR: UC selected as default type.
MTRR: 0 base 0x0000000000000000 mask 0x0000000f80000000 type 6
MTRR: 1 base 0x000000007ac00000 mask 0x0000000fffc00000 type 0
MTRR: 2 base 0x000000007b000000 mask 0x0000000fff000000 type 0
MTRR: 3 base 0x000000007c000000 mask 0x0000000ffc000000 type 0
MTRR: 4 base 0x00000000d0000000 mask 0x0000000ff0000000 type 1

4GiB total RAM: no MTRRs saved but slightly more accurate alignment

MTRR: Physical address space:
0x0000000000000000 - 0x00000000000a0000 size 0x000a0000 type 6
0x00000000000a0000 - 0x00000000000c0000 size 0x00020000 type 0
0x00000000000c0000 - 0x000000007cc00000 size 0x7cb40000 type 6
0x000000007cc00000 - 0x00000000d0000000 size 0x53400000 type 0
0x00000000d0000000 - 0x00000000e0000000 size 0x10000000 type 1
0x00000000e0000000 - 0x0000000100000000 size 0x20000000 type 0
0x0000000100000000 - 0x000000017c000000 size 0x7c000000 type 6

upstream:
MTRR: default type WB/UC MTRR counts: 7/6.
MTRR: UC selected as default type.
MTRR: 0 base 0x0000000000000000 mask 0x0000000f80000000 type 6
MTRR: 1 base 0x000000007cc00000 mask 0x0000000fffc00000 type 0
MTRR: 2 base 0x000000007d000000 mask 0x0000000fff000000 type 0
MTRR: 3 base 0x000000007e000000 mask 0x0000000ffe000000 type 0
MTRR: 4 base 0x00000000d0000000 mask 0x0000000ff0000000 type 1
MTRR: 5 base 0x0000000100000000 mask 0x0000000f00000000 type 6

patched:
MTRR: default type WB/UC MTRR counts: 7/6.
MTRR: UC selected as default type.
MTRR: 0 base 0x0000000000000000 mask 0x0000000f80000000 type 6
MTRR: 1 base 0x000000007cc00000 mask 0x0000000fffc00000 type 0
MTRR: 2 base 0x000000007d000000 mask 0x0000000fff000000 type 0
MTRR: 3 base 0x000000007e000000 mask 0x0000000ffe000000 type 0
MTRR: 4 base 0x00000000d0000000 mask 0x0000000ff0000000 type 1
MTRR: 5 base 0x0000000100000000 mask 0x0000000f80000000 type 6

8GiB total RAM: possible savings but WB still beats UC

MTRR: Physical address space:
0x0000000000000000 - 0x00000000000a0000 size 0x000a0000 type 6
0x00000000000a0000 - 0x00000000000c0000 size 0x00020000 type 0
0x00000000000c0000 - 0x000000007cc00000 size 0x7cb40000 type 6
0x000000007cc00000 - 0x00000000d0000000 size 0x53400000 type 0
0x00000000d0000000 - 0x00000000e0000000 size 0x10000000 type 1
0x00000000e0000000 - 0x0000000100000000 size 0x20000000 type 0
0x0000000100000000 - 0x000000027c000000 size 0x17c000000 type 6

upstream:
MTRR: Removing WRCOMB type. WB/UC MTRR counts: 7/11 > 6.
MTRR: default type WB/UC MTRR counts: 4/10.
MTRR: WB selected as default type.
MTRR: 0 base 0x000000007cc00000 mask 0x0000000fffc00000 type 0
MTRR: 1 base 0x000000007d000000 mask 0x0000000fff000000 type 0
MTRR: 2 base 0x000000007e000000 mask 0x0000000ffe000000 type 0
MTRR: 3 base 0x0000000080000000 mask 0x0000000f80000000 type 0

patched:
MTRR: Removing WRCOMB type. WB/UC MTRR counts: 7/7 > 6.
MTRR: default type WB/UC MTRR counts: 4/6.
MTRR: WB selected as default type.
MTRR: 0 base 0x000000007cc00000 mask 0x0000000fffc00000 type 0
MTRR: 1 base 0x000000007d000000 mask 0x0000000fff000000 type 0
MTRR: 2 base 0x000000007e000000 mask 0x0000000ffe000000 type 0
MTRR: 3 base 0x0000000080000000 mask 0x0000000f80000000 type 0

Change-Id: Iedf7dfad61d6baac91973062e2688ad866f05afd
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/21916
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>