x86: add thread support

Thread support is added for the x86 architecture. Both
the local apic and the tsc udelay() functions have a
call to thread_yield_microseconds() so as to provide an
opportunity to run pending threads.

Change-Id: Ie39b9eb565eb189676c06645bdf2a8720fe0636a
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/3207
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

src/cpu/x86/lapic/apic_timer.c

@@ -21,6 +21,7 @@
 #include <stdint.h>
 #include <console/console.h>
 #include <delay.h>
+#include <thread.h>
 #include <arch/io.h>
 #include <arch/cpu.h>
 #include <cpu/x86/car.h>
@@ -95,6 +96,9 @@ void udelay(u32 usecs)
 {
 	u32 start, value, ticks;
 
+	if (!thread_yield_microseconds(usecs))
+		return;
+
 	if (!timer_fsb || (lapic_read(LAPIC_LVTT) &
 		(LAPIC_LVT_TIMER_PERIODIC | LAPIC_LVT_MASKED)) !=
 		(LAPIC_LVT_TIMER_PERIODIC | LAPIC_LVT_MASKED))

src/cpu/x86/lapic/lapic_cpu_init.c

@@ -32,6 +32,7 @@
 #include <smp/spinlock.h>
 #include <cpu/cpu.h>
 #include <cpu/intel/speedstep.h>
+#include <thread.h>
 
 #if CONFIG_SMP && CONFIG_MAX_CPUS > 1
 /* This is a lot more paranoid now, since Linux can NOT handle
@@ -292,6 +293,7 @@ int start_cpu(device_t cpu)
 	info = (struct cpu_info *)stack_end;
 	info->index = index;
 	info->cpu   = cpu;
+	thread_init_cpu_info_non_bsp(info);
 
 	/* Advertise the new stack and index to start_cpu */
 	secondary_stack = stack_end;

src/cpu/x86/tsc/delay_tsc.c

@@ -4,6 +4,7 @@
 #include <cpu/x86/tsc.h>
 #include <smp/spinlock.h>
 #include <delay.h>
+#include <thread.h>
 
 #if !defined(__PRE_RAM__)
 
@@ -176,6 +177,9 @@ void udelay(unsigned us)
 	unsigned long long current;
 	unsigned long long clocks;
 
+	if (!thread_yield_microseconds(us))
+		return;
+
 	start = rdtscll();
 	clocks = us;
 	clocks *= get_clocks_per_usec();