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Use broadcast SIPI to startup siblings

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The current code for initializing AP cpus has several shortcomings:

- it assumes APIC IDs are sequential
- it uses only the BSP for determining the AP count, which is bad if
  there's more than one physical CPU, and CPUs are of different type

Note that the new code call cpu->ops->init() in parallel, and therefore
some CPU code needs to be changed to address that. One example are old
Intel HT enabled CPUs which can't do microcode update in parallel.

Change-Id: Ic48a1ebab6a7c52aa76765f497268af09fa38c25
Signed-off-by: Sven Schnelle <svens@stackframe.org>
Reviewed-on: http://review.coreboot.org/1139
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
This commit is contained in:
Sven Schnelle 2012-06-17 10:32:55 +02:00 • committed by Ronald G. Minnich
commit 042c1461fb
25 changed files with 136 additions and 512 deletions
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65
src/cpu/intel/hyperthreading/intel_sibling.c
View file

@ -7,13 +7,6 @@
#include <smp/spinlock.h>
#include <assert.h>
#if !CONFIG_SERIAL_CPU_INIT
#error Intel hyper-threading requires serialized cpu init
#endif
static int first_time = 1;
static int disable_siblings = !CONFIG_LOGICAL_CPUS;
/* Return true if running thread does not have the smallest lapic ID
* within a CPU core.
*/
@ -34,61 +27,3 @@ int intel_ht_sibling(void)
threads = (apic_ids / core_ids);
return !!(lapicid() & (threads-1));
}
void intel_sibling_init(device_t cpu)
{
unsigned i, siblings;
struct cpuid_result result;
/* On the bootstrap processor see if I want sibling cpus enabled */
if (first_time) {
first_time = 0;
get_option(&disable_siblings, "hyper_threading");
}
result = cpuid(1);
/* Is hyperthreading supported */
if (!(result.edx & (1 << 28))) {
return;
}
/* See how many sibling cpus we have */
siblings = (result.ebx >> 16) & 0xff;
if (siblings < 1) {
siblings = 1;
}
printk(BIOS_DEBUG, "CPU: %u %d siblings\n",
cpu->path.apic.apic_id,
siblings);
/* See if I am a sibling cpu */
if (cpu->path.apic.apic_id & (siblings -1)) {
if (disable_siblings) {
cpu->enabled = 0;
}
return;
}
/* I am the primary cpu start up my siblings */
for(i = 1; i < siblings; i++) {
struct device_path cpu_path;
device_t new;
/* Build the cpu device path */
cpu_path.type = DEVICE_PATH_APIC;
cpu_path.apic.apic_id = cpu->path.apic.apic_id + i;
/* Allocate new cpu device structure iff sibling CPU
* was not in static device tree.
*/
new = alloc_find_dev(cpu->bus, &cpu_path);
if (!new) {
continue;
}
printk(BIOS_DEBUG, "CPU: %u has sibling %u\n",
cpu->path.apic.apic_id,
new->path.apic.apic_id);
}
}