Use broadcast SIPI to startup siblings

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>

src/include/cpu/cpu.h

@@ -4,10 +4,12 @@
 #include <arch/cpu.h>
 
 #if !defined(__ROMCC__)
-void cpu_initialize(void);
+void cpu_initialize(struct bus *cpu_bus, int index);
 struct bus;
 void initialize_cpus(struct bus *cpu_bus);
-void secondary_cpu_init(void);
+void secondary_cpu_init(int index);
+
+extern unsigned int cpucount;
 
 #if !CONFIG_WAIT_BEFORE_CPUS_INIT
 	#define cpus_ready_for_init() do {} while(0)

src/include/cpu/x86/lapic.h

@@ -52,20 +52,13 @@ static inline __attribute__((always_inline)) unsigned long lapicid(void)
 }
 
 #ifndef __ROMCC__
-#if CONFIG_AP_IN_SIPI_WAIT != 1
-/* If we need to go back to sipi wait, we use the long non-inlined version of
- * this function in lapic_cpu_init.c
- */
 static inline __attribute__((always_inline)) void stop_this_cpu(void)
 {
-	/* Called by an AP when it is ready to halt and wait for a new task */
-	for(;;) {
-		hlt();
-	}
+       /* Called by an AP when it is ready to halt and wait for a new task */
+       for(;;) {
+               hlt();
+       }
 }
-#else
-void stop_this_cpu(void);
-#endif
 
 #if !defined(__PRE_RAM__)
 

src/include/device/path.h

@@ -40,6 +40,7 @@ struct apic_path
 	unsigned apic_id;
 	unsigned node_id;
 	unsigned core_id;
+	unsigned index;
 };
 
 struct apic_cluster_path