diff options
author | Aaron Durbin <adurbin@chromium.org> | 2013-05-28 14:26:29 -0500 |
---|---|---|
committer | Ronald G. Minnich <rminnich@gmail.com> | 2013-06-03 17:30:48 +0200 |
commit | 66da043e48c65e6d89b385d840e5f7c53e482db9 (patch) | |
tree | 08a1e3acfa427d8c8d71b417a6cd15554248a25a /src/cpu/intel/haswell/mp_init.c | |
parent | 27435d3bcdd4c7bccb326f77ca64a54d3fb1170a (diff) |
haswell: allow for disabled hyperthreading
There were assumptions being made in the haswell
MP and SMM code which assumed the APIC id space
was 1:1 w.r.t. cpu number. When hyperthreading is
disabled the APIC ids of the logical processors
are all even. That means the APIC id space is sparse.
Handle this situation.
Change-Id: Ibe79ab156c0a171208a77db8a252aa5b73205d6c
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/3353
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Diffstat (limited to 'src/cpu/intel/haswell/mp_init.c')
-rw-r--r-- | src/cpu/intel/haswell/mp_init.c | 22 |
1 files changed, 19 insertions, 3 deletions
diff --git a/src/cpu/intel/haswell/mp_init.c b/src/cpu/intel/haswell/mp_init.c index 357fbb291d..1358418557 100644 --- a/src/cpu/intel/haswell/mp_init.c +++ b/src/cpu/intel/haswell/mp_init.c @@ -80,6 +80,8 @@ static atomic_t num_aps; static atomic_t num_aps_relocated_smm; /* Barrier to stop APs from performing SMM relcoation. */ static int smm_relocation_barrier_begin __attribute__ ((aligned (64))); +/* Determine if hyperthreading is disabled. */ +int ht_disabled; static inline void mfence(void) { @@ -197,6 +199,8 @@ static void asmlinkage ap_init(unsigned int cpu, void *microcode_ptr) static void setup_default_sipi_vector_params(struct sipi_params *sp) { int i; + u8 apic_id; + u8 apic_id_inc; sp->gdt = (u32)&gdt; sp->gdtlimit = (u32)&gdt_end - (u32)&gdt - 1; @@ -205,9 +209,15 @@ static void setup_default_sipi_vector_params(struct sipi_params *sp) sp->stack_top = (u32)&_estack; /* Adjust the stack top to take into account cpu_info. */ sp->stack_top -= sizeof(struct cpu_info); - /* Default to linear APIC id space. */ - for (i = 0; i < CONFIG_MAX_CPUS; i++) - sp->apic_to_cpu_num[i] = i; + + /* Default to linear APIC id space if HT is enabled. If it is + * disabled the APIC ids increase by 2 as the odd numbered APIC + * ids are not present.*/ + apic_id_inc = (ht_disabled) ? 2 : 1; + for (i = 0, apic_id = 0; i < CONFIG_MAX_CPUS; i++) { + sp->apic_to_cpu_num[i] = apic_id; + apic_id += apic_id_inc; + } } #define NUM_FIXED_MTRRS 11 @@ -374,6 +384,10 @@ static int allocate_cpu_devices(struct bus *cpu_bus, int *total_hw_threads) max_cpus = CONFIG_MAX_CPUS; } + /* Determine if hyperthreading is enabled. If not, the APIC id space + * is sparse with ids incrementing by 2 instead of 1. */ + ht_disabled = num_threads == num_cores; + for (i = 1; i < max_cpus; i++) { struct device_path cpu_path; device_t new; @@ -381,6 +395,8 @@ static int allocate_cpu_devices(struct bus *cpu_bus, int *total_hw_threads) /* Build the cpu device path */ cpu_path.type = DEVICE_PATH_APIC; cpu_path.apic.apic_id = info->cpu->path.apic.apic_id + i; + if (ht_disabled) + cpu_path.apic.apic_id = cpu_path.apic.apic_id * 2; /* Allocate the new cpu device structure */ new = alloc_find_dev(cpu_bus, &cpu_path); |