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haswell: allow for disabled hyperthreading

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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>
This commit is contained in:
Aaron Durbin
2013-05-28 14:26:29 -05:00
committed by Ronald G. Minnich
parent 27435d3bcd
commit 66da043e48
3 changed files with 51 additions and 6 deletions
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22
src/cpu/intel/haswell/mp_init.c
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@ -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);