diff options
| -rw-r--r-- | src/cpu/x86/mtrr/mtrr.c | 19 |
1 files changed, 18 insertions, 1 deletions
diff --git a/src/cpu/x86/mtrr/mtrr.c b/src/cpu/x86/mtrr/mtrr.c index 005ea81063..253a7c318b 100644 --- a/src/cpu/x86/mtrr/mtrr.c +++ b/src/cpu/x86/mtrr/mtrr.c @@ -553,14 +553,31 @@ static void calc_var_mtrrs_with_hole(struct var_mtrr_state *var_state, if (!var_state->above4gb && a2 > RANGE_4GB) a2 = RANGE_4GB; + next = memranges_next_entry(var_state->addr_space, r); + b1 = a2; + + /* First check if a1 is >= 4GiB and the current etnry is the last + * entry. If so perform an optimization of covering a larger range + * defined by the base address' alignment. */ + if (a1 >= RANGE_4GB && next == NULL) { + uint32_t addr_lsb; + + addr_lsb = fls(a1); + b2 = (1 << addr_lsb) + a1; + if (b2 >= a2) { + calc_var_mtrr_range(var_state, a1, b2 - a1, mtrr_type); + return; + } + } + + /* Handle the min alignment roundup case. */ b2 = ALIGN_UP(a2, MTRR_MIN_ALIGN); /* Check against the next range. If the current range_entry is the * last entry then carving a hole is no problem. If the current entry * isn't the last entry then check that the last entry covers the * entire hole range with the default mtrr type. */ - next = memranges_next_entry(var_state->addr_space, r); if (next != NULL && (range_entry_mtrr_type(next) != var_state->def_mtrr_type || range_entry_end_mtrr_addr(next) < b2)) { |