Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 1145 insertions, 0 deletions

diff --git a/arch/i386/kernel/smpboot.c b/arch/i386/kernel/smpboot.c
new file mode 100644
index 000000000000..332ee7a1d1a1
--- /dev/null
+++ b/arch/i386/kernel/smpboot.c
@@ -0,0 +1,1145 @@
+/*
+ *	x86 SMP booting functions
+ *
+ *	(c) 1995 Alan Cox, Building #3 <alan@redhat.com>
+ *	(c) 1998, 1999, 2000 Ingo Molnar <mingo@redhat.com>
+ *
+ *	Much of the core SMP work is based on previous work by Thomas Radke, to
+ *	whom a great many thanks are extended.
+ *
+ *	Thanks to Intel for making available several different Pentium,
+ *	Pentium Pro and Pentium-II/Xeon MP machines.
+ *	Original development of Linux SMP code supported by Caldera.
+ *
+ *	This code is released under the GNU General Public License version 2 or
+ *	later.
+ *
+ *	Fixes
+ *		Felix Koop	:	NR_CPUS used properly
+ *		Jose Renau	:	Handle single CPU case.
+ *		Alan Cox	:	By repeated request 8) - Total BogoMIPS report.
+ *		Greg Wright	:	Fix for kernel stacks panic.
+ *		Erich Boleyn	:	MP v1.4 and additional changes.
+ *	Matthias Sattler	:	Changes for 2.1 kernel map.
+ *	Michel Lespinasse	:	Changes for 2.1 kernel map.
+ *	Michael Chastain	:	Change trampoline.S to gnu as.
+ *		Alan Cox	:	Dumb bug: 'B' step PPro's are fine
+ *		Ingo Molnar	:	Added APIC timers, based on code
+ *					from Jose Renau
+ *		Ingo Molnar	:	various cleanups and rewrites
+ *		Tigran Aivazian	:	fixed "0.00 in /proc/uptime on SMP" bug.
+ *	Maciej W. Rozycki	:	Bits for genuine 82489DX APICs
+ *		Martin J. Bligh	: 	Added support for multi-quad systems
+ *		Dave Jones	:	Report invalid combinations of Athlon CPUs.
+*		Rusty Russell	:	Hacked into shape for new "hotplug" boot process. */
+
+#include <linux/module.h>
+#include <linux/config.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+
+#include <linux/mm.h>
+#include <linux/sched.h>
+#include <linux/kernel_stat.h>
+#include <linux/smp_lock.h>
+#include <linux/irq.h>
+#include <linux/bootmem.h>
+
+#include <linux/delay.h>
+#include <linux/mc146818rtc.h>
+#include <asm/tlbflush.h>
+#include <asm/desc.h>
+#include <asm/arch_hooks.h>
+
+#include <mach_apic.h>
+#include <mach_wakecpu.h>
+#include <smpboot_hooks.h>
+
+/* Set if we find a B stepping CPU */
+static int __initdata smp_b_stepping;
+
+/* Number of siblings per CPU package */
+int smp_num_siblings = 1;
+int phys_proc_id[NR_CPUS]; /* Package ID of each logical CPU */
+EXPORT_SYMBOL(phys_proc_id);
+
+/* bitmap of online cpus */
+cpumask_t cpu_online_map;
+
+cpumask_t cpu_callin_map;
+cpumask_t cpu_callout_map;
+static cpumask_t smp_commenced_mask;
+
+/* Per CPU bogomips and other parameters */
+struct cpuinfo_x86 cpu_data[NR_CPUS] __cacheline_aligned;
+
+u8 x86_cpu_to_apicid[NR_CPUS] =
+			{ [0 ... NR_CPUS-1] = 0xff };
+EXPORT_SYMBOL(x86_cpu_to_apicid);
+
+/*
+ * Trampoline 80x86 program as an array.
+ */
+
+extern unsigned char trampoline_data [];
+extern unsigned char trampoline_end  [];
+static unsigned char *trampoline_base;
+static int trampoline_exec;
+
+static void map_cpu_to_logical_apicid(void);
+
+/*
+ * Currently trivial. Write the real->protected mode
+ * bootstrap into the page concerned. The caller
+ * has made sure it's suitably aligned.
+ */
+
+static unsigned long __init setup_trampoline(void)
+{
+	memcpy(trampoline_base, trampoline_data, trampoline_end - trampoline_data);
+	return virt_to_phys(trampoline_base);
+}
+
+/*
+ * We are called very early to get the low memory for the
+ * SMP bootup trampoline page.
+ */
+void __init smp_alloc_memory(void)
+{
+	trampoline_base = (void *) alloc_bootmem_low_pages(PAGE_SIZE);
+	/*
+	 * Has to be in very low memory so we can execute
+	 * real-mode AP code.
+	 */
+	if (__pa(trampoline_base) >= 0x9F000)
+		BUG();
+	/*
+	 * Make the SMP trampoline executable:
+	 */
+	trampoline_exec = set_kernel_exec((unsigned long)trampoline_base, 1);
+}
+
+/*
+ * The bootstrap kernel entry code has set these up. Save them for
+ * a given CPU
+ */
+
+static void __init smp_store_cpu_info(int id)
+{
+	struct cpuinfo_x86 *c = cpu_data + id;
+
+	*c = boot_cpu_data;
+	if (id!=0)
+		identify_cpu(c);
+	/*
+	 * Mask B, Pentium, but not Pentium MMX
+	 */
+	if (c->x86_vendor == X86_VENDOR_INTEL &&
+	    c->x86 == 5 &&
+	    c->x86_mask >= 1 && c->x86_mask <= 4 &&
+	    c->x86_model <= 3)
+		/*
+		 * Remember we have B step Pentia with bugs
+		 */
+		smp_b_stepping = 1;
+
+	/*
+	 * Certain Athlons might work (for various values of 'work') in SMP
+	 * but they are not certified as MP capable.
+	 */
+	if ((c->x86_vendor == X86_VENDOR_AMD) && (c->x86 == 6)) {
+
+		/* Athlon 660/661 is valid. */	
+		if ((c->x86_model==6) && ((c->x86_mask==0) || (c->x86_mask==1)))
+			goto valid_k7;
+
+		/* Duron 670 is valid */
+		if ((c->x86_model==7) && (c->x86_mask==0))
+			goto valid_k7;
+
+		/*
+		 * Athlon 662, Duron 671, and Athlon >model 7 have capability bit.
+		 * It's worth noting that the A5 stepping (662) of some Athlon XP's
+		 * have the MP bit set.
+		 * See http://www.heise.de/newsticker/data/jow-18.10.01-000 for more.
+		 */
+		if (((c->x86_model==6) && (c->x86_mask>=2)) ||
+		    ((c->x86_model==7) && (c->x86_mask>=1)) ||
+		     (c->x86_model> 7))
+			if (cpu_has_mp)
+				goto valid_k7;
+
+		/* If we get here, it's not a certified SMP capable AMD system. */
+		tainted |= TAINT_UNSAFE_SMP;
+	}
+
+valid_k7:
+	;
+}
+
+/*
+ * TSC synchronization.
+ *
+ * We first check whether all CPUs have their TSC's synchronized,
+ * then we print a warning if not, and always resync.
+ */
+
+static atomic_t tsc_start_flag = ATOMIC_INIT(0);
+static atomic_t tsc_count_start = ATOMIC_INIT(0);
+static atomic_t tsc_count_stop = ATOMIC_INIT(0);
+static unsigned long long tsc_values[NR_CPUS];
+
+#define NR_LOOPS 5
+
+static void __init synchronize_tsc_bp (void)
+{
+	int i;
+	unsigned long long t0;
+	unsigned long long sum, avg;
+	long long delta;
+	unsigned long one_usec;
+	int buggy = 0;
+
+	printk(KERN_INFO "checking TSC synchronization across %u CPUs: ", num_booting_cpus());
+
+	/* convert from kcyc/sec to cyc/usec */
+	one_usec = cpu_khz / 1000;
+
+	atomic_set(&tsc_start_flag, 1);
+	wmb();
+
+	/*
+	 * We loop a few times to get a primed instruction cache,
+	 * then the last pass is more or less synchronized and
+	 * the BP and APs set their cycle counters to zero all at
+	 * once. This reduces the chance of having random offsets
+	 * between the processors, and guarantees that the maximum
+	 * delay between the cycle counters is never bigger than
+	 * the latency of information-passing (cachelines) between
+	 * two CPUs.
+	 */
+	for (i = 0; i < NR_LOOPS; i++) {
+		/*
+		 * all APs synchronize but they loop on '== num_cpus'
+		 */
+		while (atomic_read(&tsc_count_start) != num_booting_cpus()-1)
+			mb();
+		atomic_set(&tsc_count_stop, 0);
+		wmb();
+		/*
+		 * this lets the APs save their current TSC:
+		 */
+		atomic_inc(&tsc_count_start);
+
+		rdtscll(tsc_values[smp_processor_id()]);
+		/*
+		 * We clear the TSC in the last loop:
+		 */
+		if (i == NR_LOOPS-1)
+			write_tsc(0, 0);
+
+		/*
+		 * Wait for all APs to leave the synchronization point:
+		 */
+		while (atomic_read(&tsc_count_stop) != num_booting_cpus()-1)
+			mb();
+		atomic_set(&tsc_count_start, 0);
+		wmb();
+		atomic_inc(&tsc_count_stop);
+	}
+
+	sum = 0;
+	for (i = 0; i < NR_CPUS; i++) {
+		if (cpu_isset(i, cpu_callout_map)) {
+			t0 = tsc_values[i];
+			sum += t0;
+		}
+	}
+	avg = sum;
+	do_div(avg, num_booting_cpus());
+
+	sum = 0;
+	for (i = 0; i < NR_CPUS; i++) {
+		if (!cpu_isset(i, cpu_callout_map))
+			continue;
+		delta = tsc_values[i] - avg;
+		if (delta < 0)
+			delta = -delta;
+		/*
+		 * We report bigger than 2 microseconds clock differences.
+		 */
+		if (delta > 2*one_usec) {
+			long realdelta;
+			if (!buggy) {
+				buggy = 1;
+				printk("\n");
+			}
+			realdelta = delta;
+			do_div(realdelta, one_usec);
+			if (tsc_values[i] < avg)
+				realdelta = -realdelta;
+
+			printk(KERN_INFO "CPU#%d had %ld usecs TSC skew, fixed it up.\n", i, realdelta);
+		}
+
+		sum += delta;
+	}
+	if (!buggy)
+		printk("passed.\n");
+}
+
+static void __init synchronize_tsc_ap (void)
+{
+	int i;
+
+	/*
+	 * Not every cpu is online at the time
+	 * this gets called, so we first wait for the BP to
+	 * finish SMP initialization:
+	 */
+	while (!atomic_read(&tsc_start_flag)) mb();
+
+	for (i = 0; i < NR_LOOPS; i++) {
+		atomic_inc(&tsc_count_start);
+		while (atomic_read(&tsc_count_start) != num_booting_cpus())
+			mb();
+
+		rdtscll(tsc_values[smp_processor_id()]);
+		if (i == NR_LOOPS-1)
+			write_tsc(0, 0);
+
+		atomic_inc(&tsc_count_stop);
+		while (atomic_read(&tsc_count_stop) != num_booting_cpus()) mb();
+	}
+}
+#undef NR_LOOPS
+
+extern void calibrate_delay(void);
+
+static atomic_t init_deasserted;
+
+static void __init smp_callin(void)
+{
+	int cpuid, phys_id;
+	unsigned long timeout;
+
+	/*
+	 * If waken up by an INIT in an 82489DX configuration
+	 * we may get here before an INIT-deassert IPI reaches
+	 * our local APIC.  We have to wait for the IPI or we'll
+	 * lock up on an APIC access.
+	 */
+	wait_for_init_deassert(&init_deasserted);
+
+	/*
+	 * (This works even if the APIC is not enabled.)
+	 */
+	phys_id = GET_APIC_ID(apic_read(APIC_ID));
+	cpuid = smp_processor_id();
+	if (cpu_isset(cpuid, cpu_callin_map)) {
+		printk("huh, phys CPU#%d, CPU#%d already present??\n",
+					phys_id, cpuid);
+		BUG();
+	}
+	Dprintk("CPU#%d (phys ID: %d) waiting for CALLOUT\n", cpuid, phys_id);
+
+	/*
+	 * STARTUP IPIs are fragile beasts as they might sometimes
+	 * trigger some glue motherboard logic. Complete APIC bus
+	 * silence for 1 second, this overestimates the time the
+	 * boot CPU is spending to send the up to 2 STARTUP IPIs
+	 * by a factor of two. This should be enough.
+	 */
+
+	/*
+	 * Waiting 2s total for startup (udelay is not yet working)
+	 */
+	timeout = jiffies + 2*HZ;
+	while (time_before(jiffies, timeout)) {
+		/*
+		 * Has the boot CPU finished it's STARTUP sequence?
+		 */
+		if (cpu_isset(cpuid, cpu_callout_map))
+			break;
+		rep_nop();
+	}
+
+	if (!time_before(jiffies, timeout)) {
+		printk("BUG: CPU%d started up but did not get a callout!\n",
+			cpuid);
+		BUG();
+	}
+
+	/*
+	 * the boot CPU has finished the init stage and is spinning
+	 * on callin_map until we finish. We are free to set up this
+	 * CPU, first the APIC. (this is probably redundant on most
+	 * boards)
+	 */
+
+	Dprintk("CALLIN, before setup_local_APIC().\n");
+	smp_callin_clear_local_apic();
+	setup_local_APIC();
+	map_cpu_to_logical_apicid();
+
+	/*
+	 * Get our bogomips.
+	 */
+	calibrate_delay();
+	Dprintk("Stack at about %p\n",&cpuid);
+
+	/*
+	 * Save our processor parameters
+	 */
+ 	smp_store_cpu_info(cpuid);
+
+	disable_APIC_timer();
+
+	/*
+	 * Allow the master to continue.
+	 */
+	cpu_set(cpuid, cpu_callin_map);
+
+	/*
+	 *      Synchronize the TSC with the BP
+	 */
+	if (cpu_has_tsc && cpu_khz)
+		synchronize_tsc_ap();
+}
+
+static int cpucount;
+
+/*
+ * Activate a secondary processor.
+ */
+static void __init start_secondary(void *unused)
+{
+	/*
+	 * Dont put anything before smp_callin(), SMP
+	 * booting is too fragile that we want to limit the
+	 * things done here to the most necessary things.
+	 */
+	cpu_init();
+	smp_callin();
+	while (!cpu_isset(smp_processor_id(), smp_commenced_mask))
+		rep_nop();
+	setup_secondary_APIC_clock();
+	if (nmi_watchdog == NMI_IO_APIC) {
+		disable_8259A_irq(0);
+		enable_NMI_through_LVT0(NULL);
+		enable_8259A_irq(0);
+	}
+	enable_APIC_timer();
+	/*
+	 * low-memory mappings have been cleared, flush them from
+	 * the local TLBs too.
+	 */
+	local_flush_tlb();
+	cpu_set(smp_processor_id(), cpu_online_map);
+
+	/* We can take interrupts now: we're officially "up". */
+	local_irq_enable();
+
+	wmb();
+	cpu_idle();
+}
+
+/*
+ * Everything has been set up for the secondary
+ * CPUs - they just need to reload everything
+ * from the task structure
+ * This function must not return.
+ */
+void __init initialize_secondary(void)
+{
+	/*
+	 * We don't actually need to load the full TSS,
+	 * basically just the stack pointer and the eip.
+	 */
+
+	asm volatile(
+		"movl %0,%%esp\n\t"
+		"jmp *%1"
+		:
+		:"r" (current->thread.esp),"r" (current->thread.eip));
+}
+
+extern struct {
+	void * esp;
+	unsigned short ss;
+} stack_start;
+
+#ifdef CONFIG_NUMA
+
+/* which logical CPUs are on which nodes */
+cpumask_t node_2_cpu_mask[MAX_NUMNODES] =
+				{ [0 ... MAX_NUMNODES-1] = CPU_MASK_NONE };
+/* which node each logical CPU is on */
+int cpu_2_node[NR_CPUS] = { [0 ... NR_CPUS-1] = 0 };
+EXPORT_SYMBOL(cpu_2_node);
+
+/* set up a mapping between cpu and node. */
+static inline void map_cpu_to_node(int cpu, int node)
+{
+	printk("Mapping cpu %d to node %d\n", cpu, node);
+	cpu_set(cpu, node_2_cpu_mask[node]);
+	cpu_2_node[cpu] = node;
+}
+
+/* undo a mapping between cpu and node. */
+static inline void unmap_cpu_to_node(int cpu)
+{
+	int node;
+
+	printk("Unmapping cpu %d from all nodes\n", cpu);
+	for (node = 0; node < MAX_NUMNODES; node ++)
+		cpu_clear(cpu, node_2_cpu_mask[node]);
+	cpu_2_node[cpu] = 0;
+}
+#else /* !CONFIG_NUMA */
+
+#define map_cpu_to_node(cpu, node)	({})
+#define unmap_cpu_to_node(cpu)	({})
+
+#endif /* CONFIG_NUMA */
+
+u8 cpu_2_logical_apicid[NR_CPUS] = { [0 ... NR_CPUS-1] = BAD_APICID };
+
+static void map_cpu_to_logical_apicid(void)
+{
+	int cpu = smp_processor_id();
+	int apicid = logical_smp_processor_id();
+
+	cpu_2_logical_apicid[cpu] = apicid;
+	map_cpu_to_node(cpu, apicid_to_node(apicid));
+}
+
+static void unmap_cpu_to_logical_apicid(int cpu)
+{
+	cpu_2_logical_apicid[cpu] = BAD_APICID;
+	unmap_cpu_to_node(cpu);
+}
+
+#if APIC_DEBUG
+static inline void __inquire_remote_apic(int apicid)
+{
+	int i, regs[] = { APIC_ID >> 4, APIC_LVR >> 4, APIC_SPIV >> 4 };
+	char *names[] = { "ID", "VERSION", "SPIV" };
+	int timeout, status;
+
+	printk("Inquiring remote APIC #%d...\n", apicid);
+
+	for (i = 0; i < sizeof(regs) / sizeof(*regs); i++) {
+		printk("... APIC #%d %s: ", apicid, names[i]);
+
+		/*
+		 * Wait for idle.
+		 */
+		apic_wait_icr_idle();
+
+		apic_write_around(APIC_ICR2, SET_APIC_DEST_FIELD(apicid));
+		apic_write_around(APIC_ICR, APIC_DM_REMRD | regs[i]);
+
+		timeout = 0;
+		do {
+			udelay(100);
+			status = apic_read(APIC_ICR) & APIC_ICR_RR_MASK;
+		} while (status == APIC_ICR_RR_INPROG && timeout++ < 1000);
+
+		switch (status) {
+		case APIC_ICR_RR_VALID:
+			status = apic_read(APIC_RRR);
+			printk("%08x\n", status);
+			break;
+		default:
+			printk("failed\n");
+		}
+	}
+}
+#endif
+
+#ifdef WAKE_SECONDARY_VIA_NMI
+/* 
+ * Poke the other CPU in the eye via NMI to wake it up. Remember that the normal
+ * INIT, INIT, STARTUP sequence will reset the chip hard for us, and this
+ * won't ... remember to clear down the APIC, etc later.
+ */
+static int __init
+wakeup_secondary_cpu(int logical_apicid, unsigned long start_eip)
+{
+	unsigned long send_status = 0, accept_status = 0;
+	int timeout, maxlvt;
+
+	/* Target chip */
+	apic_write_around(APIC_ICR2, SET_APIC_DEST_FIELD(logical_apicid));
+
+	/* Boot on the stack */
+	/* Kick the second */
+	apic_write_around(APIC_ICR, APIC_DM_NMI | APIC_DEST_LOGICAL);
+
+	Dprintk("Waiting for send to finish...\n");
+	timeout = 0;
+	do {
+		Dprintk("+");
+		udelay(100);
+		send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY;
+	} while (send_status && (timeout++ < 1000));
+
+	/*
+	 * Give the other CPU some time to accept the IPI.
+	 */
+	udelay(200);
+	/*
+	 * Due to the Pentium erratum 3AP.
+	 */
+	maxlvt = get_maxlvt();
+	if (maxlvt > 3) {
+		apic_read_around(APIC_SPIV);
+		apic_write(APIC_ESR, 0);
+	}
+	accept_status = (apic_read(APIC_ESR) & 0xEF);
+	Dprintk("NMI sent.\n");
+
+	if (send_status)
+		printk("APIC never delivered???\n");
+	if (accept_status)
+		printk("APIC delivery error (%lx).\n", accept_status);
+
+	return (send_status | accept_status);
+}
+#endif	/* WAKE_SECONDARY_VIA_NMI */
+
+#ifdef WAKE_SECONDARY_VIA_INIT
+static int __init
+wakeup_secondary_cpu(int phys_apicid, unsigned long start_eip)
+{
+	unsigned long send_status = 0, accept_status = 0;
+	int maxlvt, timeout, num_starts, j;
+
+	/*
+	 * Be paranoid about clearing APIC errors.
+	 */
+	if (APIC_INTEGRATED(apic_version[phys_apicid])) {
+		apic_read_around(APIC_SPIV);
+		apic_write(APIC_ESR, 0);
+		apic_read(APIC_ESR);
+	}
+
+	Dprintk("Asserting INIT.\n");
+
+	/*
+	 * Turn INIT on target chip
+	 */
+	apic_write_around(APIC_ICR2, SET_APIC_DEST_FIELD(phys_apicid));
+
+	/*
+	 * Send IPI
+	 */
+	apic_write_around(APIC_ICR, APIC_INT_LEVELTRIG | APIC_INT_ASSERT
+				| APIC_DM_INIT);
+
+	Dprintk("Waiting for send to finish...\n");
+	timeout = 0;
+	do {
+		Dprintk("+");
+		udelay(100);
+		send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY;
+	} while (send_status && (timeout++ < 1000));
+
+	mdelay(10);
+
+	Dprintk("Deasserting INIT.\n");
+
+	/* Target chip */
+	apic_write_around(APIC_ICR2, SET_APIC_DEST_FIELD(phys_apicid));
+
+	/* Send IPI */
+	apic_write_around(APIC_ICR, APIC_INT_LEVELTRIG | APIC_DM_INIT);
+
+	Dprintk("Waiting for send to finish...\n");
+	timeout = 0;
+	do {
+		Dprintk("+");
+		udelay(100);
+		send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY;
+	} while (send_status && (timeout++ < 1000));
+
+	atomic_set(&init_deasserted, 1);
+
+	/*
+	 * Should we send STARTUP IPIs ?
+	 *
+	 * Determine this based on the APIC version.
+	 * If we don't have an integrated APIC, don't send the STARTUP IPIs.
+	 */
+	if (APIC_INTEGRATED(apic_version[phys_apicid]))
+		num_starts = 2;
+	else
+		num_starts = 0;
+
+	/*
+	 * Run STARTUP IPI loop.
+	 */
+	Dprintk("#startup loops: %d.\n", num_starts);
+
+	maxlvt = get_maxlvt();
+
+	for (j = 1; j <= num_starts; j++) {
+		Dprintk("Sending STARTUP #%d.\n",j);
+		apic_read_around(APIC_SPIV);
+		apic_write(APIC_ESR, 0);
+		apic_read(APIC_ESR);
+		Dprintk("After apic_write.\n");
+
+		/*
+		 * STARTUP IPI
+		 */
+
+		/* Target chip */
+		apic_write_around(APIC_ICR2, SET_APIC_DEST_FIELD(phys_apicid));
+
+		/* Boot on the stack */
+		/* Kick the second */
+		apic_write_around(APIC_ICR, APIC_DM_STARTUP
+					| (start_eip >> 12));
+
+		/*
+		 * Give the other CPU some time to accept the IPI.
+		 */
+		udelay(300);
+
+		Dprintk("Startup point 1.\n");
+
+		Dprintk("Waiting for send to finish...\n");
+		timeout = 0;
+		do {
+			Dprintk("+");
+			udelay(100);
+			send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY;
+		} while (send_status && (timeout++ < 1000));
+
+		/*
+		 * Give the other CPU some time to accept the IPI.
+		 */
+		udelay(200);
+		/*
+		 * Due to the Pentium erratum 3AP.
+		 */
+		if (maxlvt > 3) {
+			apic_read_around(APIC_SPIV);
+			apic_write(APIC_ESR, 0);
+		}
+		accept_status = (apic_read(APIC_ESR) & 0xEF);
+		if (send_status || accept_status)
+			break;
+	}
+	Dprintk("After Startup.\n");
+
+	if (send_status)
+		printk("APIC never delivered???\n");
+	if (accept_status)
+		printk("APIC delivery error (%lx).\n", accept_status);
+
+	return (send_status | accept_status);
+}
+#endif	/* WAKE_SECONDARY_VIA_INIT */
+
+extern cpumask_t cpu_initialized;
+
+static int __init do_boot_cpu(int apicid)
+/*
+ * NOTE - on most systems this is a PHYSICAL apic ID, but on multiquad
+ * (ie clustered apic addressing mode), this is a LOGICAL apic ID.
+ * Returns zero if CPU booted OK, else error code from wakeup_secondary_cpu.
+ */
+{
+	struct task_struct *idle;
+	unsigned long boot_error;
+	int timeout, cpu;
+	unsigned long start_eip;
+	unsigned short nmi_high = 0, nmi_low = 0;
+
+	cpu = ++cpucount;
+	/*
+	 * We can't use kernel_thread since we must avoid to
+	 * reschedule the child.
+	 */
+	idle = fork_idle(cpu);
+	if (IS_ERR(idle))
+		panic("failed fork for CPU %d", cpu);
+	idle->thread.eip = (unsigned long) start_secondary;
+	/* start_eip had better be page-aligned! */
+	start_eip = setup_trampoline();
+
+	/* So we see what's up   */
+	printk("Booting processor %d/%d eip %lx\n", cpu, apicid, start_eip);
+	/* Stack for startup_32 can be just as for start_secondary onwards */
+	stack_start.esp = (void *) idle->thread.esp;
+
+	irq_ctx_init(cpu);
+
+	/*
+	 * This grunge runs the startup process for
+	 * the targeted processor.
+	 */
+
+	atomic_set(&init_deasserted, 0);
+
+	Dprintk("Setting warm reset code and vector.\n");
+
+	store_NMI_vector(&nmi_high, &nmi_low);
+
+	smpboot_setup_warm_reset_vector(start_eip);
+
+	/*
+	 * Starting actual IPI sequence...
+	 */
+	boot_error = wakeup_secondary_cpu(apicid, start_eip);
+
+	if (!boot_error) {
+		/*
+		 * allow APs to start initializing.
+		 */
+		Dprintk("Before Callout %d.\n", cpu);
+		cpu_set(cpu, cpu_callout_map);
+		Dprintk("After Callout %d.\n", cpu);
+
+		/*
+		 * Wait 5s total for a response
+		 */
+		for (timeout = 0; timeout < 50000; timeout++) {
+			if (cpu_isset(cpu, cpu_callin_map))
+				break;	/* It has booted */
+			udelay(100);
+		}
+
+		if (cpu_isset(cpu, cpu_callin_map)) {
+			/* number CPUs logically, starting from 1 (BSP is 0) */
+			Dprintk("OK.\n");
+			printk("CPU%d: ", cpu);
+			print_cpu_info(&cpu_data[cpu]);
+			Dprintk("CPU has booted.\n");
+		} else {
+			boot_error= 1;
+			if (*((volatile unsigned char *)trampoline_base)
+					== 0xA5)
+				/* trampoline started but...? */
+				printk("Stuck ??\n");
+			else
+				/* trampoline code not run */
+				printk("Not responding.\n");
+			inquire_remote_apic(apicid);
+		}
+	}
+	x86_cpu_to_apicid[cpu] = apicid;
+	if (boot_error) {
+		/* Try to put things back the way they were before ... */
+		unmap_cpu_to_logical_apicid(cpu);
+		cpu_clear(cpu, cpu_callout_map); /* was set here (do_boot_cpu()) */
+		cpu_clear(cpu, cpu_initialized); /* was set by cpu_init() */
+		cpucount--;
+	}
+
+	/* mark "stuck" area as not stuck */
+	*((volatile unsigned long *)trampoline_base) = 0;
+
+	return boot_error;
+}
+
+static void smp_tune_scheduling (void)
+{
+	unsigned long cachesize;       /* kB   */
+	unsigned long bandwidth = 350; /* MB/s */
+	/*
+	 * Rough estimation for SMP scheduling, this is the number of
+	 * cycles it takes for a fully memory-limited process to flush
+	 * the SMP-local cache.
+	 *
+	 * (For a P5 this pretty much means we will choose another idle
+	 *  CPU almost always at wakeup time (this is due to the small
+	 *  L1 cache), on PIIs it's around 50-100 usecs, depending on
+	 *  the cache size)
+	 */
+
+	if (!cpu_khz) {
+		/*
+		 * this basically disables processor-affinity
+		 * scheduling on SMP without a TSC.
+		 */
+		return;
+	} else {
+		cachesize = boot_cpu_data.x86_cache_size;
+		if (cachesize == -1) {
+			cachesize = 16; /* Pentiums, 2x8kB cache */
+			bandwidth = 100;
+		}
+	}
+}
+
+/*
+ * Cycle through the processors sending APIC IPIs to boot each.
+ */
+
+static int boot_cpu_logical_apicid;
+/* Where the IO area was mapped on multiquad, always 0 otherwise */
+void *xquad_portio;
+
+cpumask_t cpu_sibling_map[NR_CPUS] __cacheline_aligned;
+
+static void __init smp_boot_cpus(unsigned int max_cpus)
+{
+	int apicid, cpu, bit, kicked;
+	unsigned long bogosum = 0;
+
+	/*
+	 * Setup boot CPU information
+	 */
+	smp_store_cpu_info(0); /* Final full version of the data */
+	printk("CPU%d: ", 0);
+	print_cpu_info(&cpu_data[0]);
+
+	boot_cpu_physical_apicid = GET_APIC_ID(apic_read(APIC_ID));
+	boot_cpu_logical_apicid = logical_smp_processor_id();
+	x86_cpu_to_apicid[0] = boot_cpu_physical_apicid;
+
+	current_thread_info()->cpu = 0;
+	smp_tune_scheduling();
+	cpus_clear(cpu_sibling_map[0]);
+	cpu_set(0, cpu_sibling_map[0]);
+
+	/*
+	 * If we couldn't find an SMP configuration at boot time,
+	 * get out of here now!
+	 */
+	if (!smp_found_config && !acpi_lapic) {
+		printk(KERN_NOTICE "SMP motherboard not detected.\n");
+		smpboot_clear_io_apic_irqs();
+		phys_cpu_present_map = physid_mask_of_physid(0);
+		if (APIC_init_uniprocessor())
+			printk(KERN_NOTICE "Local APIC not detected."
+					   " Using dummy APIC emulation.\n");
+		map_cpu_to_logical_apicid();
+		return;
+	}
+
+	/*
+	 * Should not be necessary because the MP table should list the boot
+	 * CPU too, but we do it for the sake of robustness anyway.
+	 * Makes no sense to do this check in clustered apic mode, so skip it
+	 */
+	if (!check_phys_apicid_present(boot_cpu_physical_apicid)) {
+		printk("weird, boot CPU (#%d) not listed by the BIOS.\n",
+				boot_cpu_physical_apicid);
+		physid_set(hard_smp_processor_id(), phys_cpu_present_map);
+	}
+
+	/*
+	 * If we couldn't find a local APIC, then get out of here now!
+	 */
+	if (APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid]) && !cpu_has_apic) {
+		printk(KERN_ERR "BIOS bug, local APIC #%d not detected!...\n",
+			boot_cpu_physical_apicid);
+		printk(KERN_ERR "... forcing use of dummy APIC emulation. (tell your hw vendor)\n");
+		smpboot_clear_io_apic_irqs();
+		phys_cpu_present_map = physid_mask_of_physid(0);
+		return;
+	}
+
+	verify_local_APIC();
+
+	/*
+	 * If SMP should be disabled, then really disable it!
+	 */
+	if (!max_cpus) {
+		smp_found_config = 0;
+		printk(KERN_INFO "SMP mode deactivated, forcing use of dummy APIC emulation.\n");
+		smpboot_clear_io_apic_irqs();
+		phys_cpu_present_map = physid_mask_of_physid(0);
+		return;
+	}
+
+	connect_bsp_APIC();
+	setup_local_APIC();
+	map_cpu_to_logical_apicid();
+
+
+	setup_portio_remap();
+
+	/*
+	 * Scan the CPU present map and fire up the other CPUs via do_boot_cpu
+	 *
+	 * In clustered apic mode, phys_cpu_present_map is a constructed thus:
+	 * bits 0-3 are quad0, 4-7 are quad1, etc. A perverse twist on the 
+	 * clustered apic ID.
+	 */
+	Dprintk("CPU present map: %lx\n", physids_coerce(phys_cpu_present_map));
+
+	kicked = 1;
+	for (bit = 0; kicked < NR_CPUS && bit < MAX_APICS; bit++) {
+		apicid = cpu_present_to_apicid(bit);
+		/*
+		 * Don't even attempt to start the boot CPU!
+		 */
+		if ((apicid == boot_cpu_apicid) || (apicid == BAD_APICID))
+			continue;
+
+		if (!check_apicid_present(bit))
+			continue;
+		if (max_cpus <= cpucount+1)
+			continue;
+
+		if (do_boot_cpu(apicid))
+			printk("CPU #%d not responding - cannot use it.\n",
+								apicid);
+		else
+			++kicked;
+	}
+
+	/*
+	 * Cleanup possible dangling ends...
+	 */
+	smpboot_restore_warm_reset_vector();
+
+	/*
+	 * Allow the user to impress friends.
+	 */
+	Dprintk("Before bogomips.\n");
+	for (cpu = 0; cpu < NR_CPUS; cpu++)
+		if (cpu_isset(cpu, cpu_callout_map))
+			bogosum += cpu_data[cpu].loops_per_jiffy;
+	printk(KERN_INFO
+		"Total of %d processors activated (%lu.%02lu BogoMIPS).\n",
+		cpucount+1,
+		bogosum/(500000/HZ),
+		(bogosum/(5000/HZ))%100);
+	
+	Dprintk("Before bogocount - setting activated=1.\n");
+
+	if (smp_b_stepping)
+		printk(KERN_WARNING "WARNING: SMP operation may be unreliable with B stepping processors.\n");
+
+	/*
+	 * Don't taint if we are running SMP kernel on a single non-MP
+	 * approved Athlon
+	 */
+	if (tainted & TAINT_UNSAFE_SMP) {
+		if (cpucount)
+			printk (KERN_INFO "WARNING: This combination of AMD processors is not suitable for SMP.\n");
+		else
+			tainted &= ~TAINT_UNSAFE_SMP;
+	}
+
+	Dprintk("Boot done.\n");
+
+	/*
+	 * construct cpu_sibling_map[], so that we can tell sibling CPUs
+	 * efficiently.
+	 */
+	for (cpu = 0; cpu < NR_CPUS; cpu++)
+		cpus_clear(cpu_sibling_map[cpu]);
+
+	for (cpu = 0; cpu < NR_CPUS; cpu++) {
+		int siblings = 0;
+		int i;
+		if (!cpu_isset(cpu, cpu_callout_map))
+			continue;
+
+		if (smp_num_siblings > 1) {
+			for (i = 0; i < NR_CPUS; i++) {
+				if (!cpu_isset(i, cpu_callout_map))
+					continue;
+				if (phys_proc_id[cpu] == phys_proc_id[i]) {
+					siblings++;
+					cpu_set(i, cpu_sibling_map[cpu]);
+				}
+			}
+		} else {
+			siblings++;
+			cpu_set(cpu, cpu_sibling_map[cpu]);
+		}
+
+		if (siblings != smp_num_siblings)
+			printk(KERN_WARNING "WARNING: %d siblings found for CPU%d, should be %d\n", siblings, cpu, smp_num_siblings);
+	}
+
+	if (nmi_watchdog == NMI_LOCAL_APIC)
+		check_nmi_watchdog();
+
+	smpboot_setup_io_apic();
+
+	setup_boot_APIC_clock();
+
+	/*
+	 * Synchronize the TSC with the AP
+	 */
+	if (cpu_has_tsc && cpucount && cpu_khz)
+		synchronize_tsc_bp();
+}
+
+/* These are wrappers to interface to the new boot process.  Someone
+   who understands all this stuff should rewrite it properly. --RR 15/Jul/02 */
+void __init smp_prepare_cpus(unsigned int max_cpus)
+{
+	smp_boot_cpus(max_cpus);
+}
+
+void __devinit smp_prepare_boot_cpu(void)
+{
+	cpu_set(smp_processor_id(), cpu_online_map);
+	cpu_set(smp_processor_id(), cpu_callout_map);
+}
+
+int __devinit __cpu_up(unsigned int cpu)
+{
+	/* This only works at boot for x86.  See "rewrite" above. */
+	if (cpu_isset(cpu, smp_commenced_mask)) {
+		local_irq_enable();
+		return -ENOSYS;
+	}
+
+	/* In case one didn't come up */
+	if (!cpu_isset(cpu, cpu_callin_map)) {
+		local_irq_enable();
+		return -EIO;
+	}
+
+	local_irq_enable();
+	/* Unleash the CPU! */
+	cpu_set(cpu, smp_commenced_mask);
+	while (!cpu_isset(cpu, cpu_online_map))
+		mb();
+	return 0;
+}
+
+void __init smp_cpus_done(unsigned int max_cpus)
+{
+#ifdef CONFIG_X86_IO_APIC
+	setup_ioapic_dest();
+#endif
+	zap_low_mappings();
+	/*
+	 * Disable executability of the SMP trampoline:
+	 */
+	set_kernel_exec((unsigned long)trampoline_base, trampoline_exec);
+}
+
+void __init smp_intr_init(void)
+{
+	/*
+	 * IRQ0 must be given a fixed assignment and initialized,
+	 * because it's used before the IO-APIC is set up.
+	 */
+	set_intr_gate(FIRST_DEVICE_VECTOR, interrupt[0]);
+
+	/*
+	 * The reschedule interrupt is a CPU-to-CPU reschedule-helper
+	 * IPI, driven by wakeup.
+	 */
+	set_intr_gate(RESCHEDULE_VECTOR, reschedule_interrupt);
+
+	/* IPI for invalidation */
+	set_intr_gate(INVALIDATE_TLB_VECTOR, invalidate_interrupt);
+
+	/* IPI for generic function call */
+	set_intr_gate(CALL_FUNCTION_VECTOR, call_function_interrupt);
+}