diff options
Diffstat (limited to 'src/cpu/x86/mtrr/mtrr.c')
| -rw-r--r-- | src/cpu/x86/mtrr/mtrr.c | 90 |
1 files changed, 79 insertions, 11 deletions
diff --git a/src/cpu/x86/mtrr/mtrr.c b/src/cpu/x86/mtrr/mtrr.c index 8033e792bc..3ee907f96a 100644 --- a/src/cpu/x86/mtrr/mtrr.c +++ b/src/cpu/x86/mtrr/mtrr.c @@ -154,6 +154,24 @@ static int filter_vga_wrcomb(struct device *dev, struct resource *res) return 1; } +static void print_physical_address_space(const struct memranges *addr_space, + const char *identifier) +{ + const struct range_entry *r; + + if (identifier) + printk(BIOS_DEBUG, "MTRR: %s Physical address space:\n", + identifier); + else + printk(BIOS_DEBUG, "MTRR: Physical address space:\n"); + + memranges_each_entry(r, addr_space) + printk(BIOS_DEBUG, + "0x%016llx - 0x%016llx size 0x%08llx type %ld\n", + range_entry_base(r), range_entry_end(r), + range_entry_size(r), range_entry_tag(r)); +} + static struct memranges *get_physical_address_space(void) { static struct memranges *addr_space; @@ -163,7 +181,6 @@ static struct memranges *get_physical_address_space(void) * uncacheable ranges, such as graphics memory, at resource insertion * time remove uncacheable regions from the cacheable ones. */ if (addr_space == NULL) { - struct range_entry *r; unsigned long mask; unsigned long match; @@ -193,12 +210,7 @@ static struct memranges *get_physical_address_space(void) RANGE_TO_PHYS_ADDR(RANGE_4GB), MTRR_TYPE_UNCACHEABLE); - printk(BIOS_DEBUG, "MTRR: Physical address space:\n"); - memranges_each_entry(r, addr_space) - printk(BIOS_DEBUG, - "0x%016llx - 0x%016llx size 0x%08llx type %ld\n", - range_entry_base(r), range_entry_end(r), - range_entry_size(r), range_entry_tag(r)); + print_physical_address_space(addr_space, NULL); } return addr_space; @@ -380,11 +392,10 @@ struct var_mtrr_state { static void clear_var_mtrr(int index) { - msr_t msr_val; + msr_t msr = { .lo = 0, .hi = 0 }; - msr_val = rdmsr(MTRR_PHYS_MASK(index)); - msr_val.lo &= ~MTRR_PHYS_MASK_VALID; - wrmsr(MTRR_PHYS_MASK(index), msr_val); + wrmsr(MTRR_PHYS_BASE(index), msr); + wrmsr(MTRR_PHYS_MASK(index), msr); } static void prep_var_mtrr(struct var_mtrr_state *var_state, @@ -817,3 +828,60 @@ void x86_mtrr_check(void) post_code(0x93); } + +static bool put_back_original_solution; + +void mtrr_use_temp_range(uintptr_t begin, size_t size, int type) +{ + const struct range_entry *r; + const struct memranges *orig; + struct var_mtrr_solution sol; + struct memranges addr_space; + const int above4gb = 1; /* Cover above 4GiB by default. */ + int address_bits; + + /* Make a copy of the original address space and tweak it with the + * provided range. */ + memranges_init_empty(&addr_space, NULL, 0); + orig = get_physical_address_space(); + memranges_each_entry(r, orig) { + unsigned long tag = range_entry_tag(r); + + /* Remove any special tags from original solution. */ + tag &= ~MTRR_RANGE_UC_USE_HOLE; + + /* Remove any write combining MTRRs from the temporary + * solution as it just fragments the address space. */ + if (tag == MTRR_TYPE_WRCOMB) + tag = MTRR_TYPE_UNCACHEABLE; + + memranges_insert(&addr_space, range_entry_base(r), + range_entry_size(r), tag); + } + + /* Place new range into the address space. */ + memranges_insert(&addr_space, begin, size, type); + + print_physical_address_space(&addr_space, "TEMPORARY"); + + /* Calculate a new solution with the updated address space. */ + address_bits = cpu_phys_address_size(); + memset(&sol, 0, sizeof(sol)); + sol.mtrr_default_type = + calc_var_mtrrs(&addr_space, above4gb, address_bits); + prepare_var_mtrrs(&addr_space, sol.mtrr_default_type, + above4gb, address_bits, &sol); + commit_var_mtrrs(&sol); + + memranges_teardown(&addr_space); + put_back_original_solution = true; +} + +static void remove_temp_solution(void *unused) +{ + if (put_back_original_solution) + commit_var_mtrrs(&mtrr_global_solution); +} + +BOOT_STATE_INIT_ENTRY(BS_OS_RESUME, BS_ON_ENTRY, remove_temp_solution, NULL); +BOOT_STATE_INIT_ENTRY(BS_PAYLOAD_LOAD, BS_ON_EXIT, remove_temp_solution, NULL); |