[deliverable/linux.git] / arch / x86_64 / kernel / genapic.c

/*
 * Copyright 2004 James Cleverdon, IBM.
 * Subject to the GNU Public License, v.2
 *
 * Generic APIC sub-arch probe layer.
 *
 * Hacked for x86-64 by James Cleverdon from i386 architecture code by
 * Martin Bligh, Andi Kleen, James Bottomley, John Stultz, and
 * James Cleverdon.
 */
#include <linux/config.h>
#include <linux/threads.h>
#include <linux/cpumask.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/ctype.h>
#include <linux/init.h>
#include <linux/module.h>

#include <asm/smp.h>
#include <asm/ipi.h>

#if defined(CONFIG_ACPI_BUS)
#include <acpi/acpi_bus.h>
#endif

/* which logical CPU number maps to which CPU (physical APIC ID) */
u8 x86_cpu_to_apicid[NR_CPUS] __read_mostly = { [0 ... NR_CPUS-1] = BAD_APICID };
EXPORT_SYMBOL(x86_cpu_to_apicid);
u8 x86_cpu_to_log_apicid[NR_CPUS] = { [0 ... NR_CPUS-1] = BAD_APICID };

extern struct genapic apic_cluster;
extern struct genapic apic_flat;
extern struct genapic apic_physflat;

struct genapic *genapic = &apic_flat;


/*
 * Check the APIC IDs in bios_cpu_apicid and choose the APIC mode.
 */
void __init clustered_apic_check(void)
{
	long i;
	u8 clusters, max_cluster;
	u8 id;
	u8 cluster_cnt[NUM_APIC_CLUSTERS];
	int num_cpus = 0;

#if defined(CONFIG_ACPI_BUS)
	/*
	 * Some x86_64 machines use physical APIC mode regardless of how many
	 * procs/clusters are present (x86_64 ES7000 is an example).
	 */
	if (acpi_fadt.revision > FADT2_REVISION_ID)
		if (acpi_fadt.force_apic_physical_destination_mode) {
			genapic = &apic_cluster;
			goto print;
		}
#endif

	memset(cluster_cnt, 0, sizeof(cluster_cnt));
	for (i = 0; i < NR_CPUS; i++) {
		id = bios_cpu_apicid[i];
		if (id == BAD_APICID)
			continue;
		num_cpus++;
		cluster_cnt[APIC_CLUSTERID(id)]++;
	}

	/* Don't use clustered mode on AMD platforms. */
 	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) {
		genapic = &apic_physflat;
#ifndef CONFIG_CPU_HOTPLUG
		/* In the CPU hotplug case we cannot use broadcast mode
		   because that opens a race when a CPU is removed.
		   Stay at physflat mode in this case.
		   It is bad to do this unconditionally though. Once
		   we have ACPI platform support for CPU hotplug
		   we should detect hotplug capablity from ACPI tables and
		   only do this when really needed. -AK */
		if (num_cpus <= 8)
			genapic = &apic_flat;
#endif
 		goto print;
 	}

	clusters = 0;
	max_cluster = 0;

	for (i = 0; i < NUM_APIC_CLUSTERS; i++) {
		if (cluster_cnt[i] > 0) {
			++clusters;
			if (cluster_cnt[i] > max_cluster)
				max_cluster = cluster_cnt[i];
		}
	}

	/*
	 * If we have clusters <= 1 and CPUs <= 8 in cluster 0, then flat mode,
	 * else if max_cluster <= 4 and cluster_cnt[15] == 0, clustered logical
	 * else physical mode.
	 * (We don't use lowest priority delivery + HW APIC IRQ steering, so
	 * can ignore the clustered logical case and go straight to physical.)
	 */
	if (clusters <= 1 && max_cluster <= 8 && cluster_cnt[0] == max_cluster)
		genapic = &apic_flat;
	else
		genapic = &apic_cluster;

print:
	printk(KERN_INFO "Setting APIC routing to %s\n", genapic->name);
}

/* Same for both flat and clustered. */

void send_IPI_self(int vector)
{
	__send_IPI_shortcut(APIC_DEST_SELF, vector, APIC_DEST_PHYSICAL);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Copyright 2004 James Cleverdon, IBM.
	3	* Subject to the GNU Public License, v.2
	4	*
	5	* Generic APIC sub-arch probe layer.
	6	*
	7	* Hacked for x86-64 by James Cleverdon from i386 architecture code by
	8	* Martin Bligh, Andi Kleen, James Bottomley, John Stultz, and
	9	* James Cleverdon.
	10	*/
	11	#include <linux/config.h>
	12	#include <linux/threads.h>
	13	#include <linux/cpumask.h>
	14	#include <linux/string.h>
	15	#include <linux/kernel.h>
	16	#include <linux/ctype.h>
	17	#include <linux/init.h>
	18	#include <linux/module.h>
	19
	20	#include <asm/smp.h>
	21	#include <asm/ipi.h>
	22
90660ec3 JD	23	#if defined(CONFIG_ACPI_BUS)
	24	#include <acpi/acpi_bus.h>
	25	#endif
	26
1da177e4	27	/* which logical CPU number maps to which CPU (physical APIC ID) */
6c231b7b	28	u8 x86_cpu_to_apicid[NR_CPUS] __read_mostly = { [0 ... NR_CPUS-1] = BAD_APICID };
1da177e4 LT	29	EXPORT_SYMBOL(x86_cpu_to_apicid);
	30	u8 x86_cpu_to_log_apicid[NR_CPUS] = { [0 ... NR_CPUS-1] = BAD_APICID };
	31
	32	extern struct genapic apic_cluster;
	33	extern struct genapic apic_flat;
f8d31193	34	extern struct genapic apic_physflat;
1da177e4 LT	35
	36	struct genapic *genapic = &apic_flat;
	37
	38
	39	/*
	40	* Check the APIC IDs in bios_cpu_apicid and choose the APIC mode.
	41	*/
	42	void __init clustered_apic_check(void)
	43	{
	44	long i;
	45	u8 clusters, max_cluster;
	46	u8 id;
	47	u8 cluster_cnt[NUM_APIC_CLUSTERS];
f8d31193	48	int num_cpus = 0;
1da177e4	49
90660ec3 JD	50	#if defined(CONFIG_ACPI_BUS)
	51	/*
	52	* Some x86_64 machines use physical APIC mode regardless of how many
	53	* procs/clusters are present (x86_64 ES7000 is an example).
	54	*/
	55	if (acpi_fadt.revision > FADT2_REVISION_ID)
	56	if (acpi_fadt.force_apic_physical_destination_mode) {
	57	genapic = &apic_cluster;
	58	goto print;
	59	}
	60	#endif
	61
1da177e4	62	memset(cluster_cnt, 0, sizeof(cluster_cnt));
1da177e4 LT	63	for (i = 0; i < NR_CPUS; i++) {
1da177e4 LT	64	id = bios_cpu_apicid[i];
f8d31193 AK	65	if (id == BAD_APICID)
	66	continue;
	67	num_cpus++;
	68	cluster_cnt[APIC_CLUSTERID(id)]++;
1da177e4 LT	69	}
1da177e4 LT	70
f8d31193 AK	71	/* Don't use clustered mode on AMD platforms. */
	72	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) {
	73	genapic = &apic_physflat;
	74	#ifndef CONFIG_CPU_HOTPLUG
	75	/* In the CPU hotplug case we cannot use broadcast mode
	76	because that opens a race when a CPU is removed.
	77	Stay at physflat mode in this case.
	78	It is bad to do this unconditionally though. Once
	79	we have ACPI platform support for CPU hotplug
	80	we should detect hotplug capablity from ACPI tables and
	81	only do this when really needed. -AK */
	82	if (num_cpus <= 8)
	83	genapic = &apic_flat;
	84	#endif
	85	goto print;
	86	}
	87
1da177e4 LT	88	clusters = 0;
1da177e4 LT	89	max_cluster = 0;
f8d31193	90
1da177e4 LT	91	for (i = 0; i < NUM_APIC_CLUSTERS; i++) {
	92	if (cluster_cnt[i] > 0) {
	93	++clusters;
	94	if (cluster_cnt[i] > max_cluster)
	95	max_cluster = cluster_cnt[i];
	96	}
	97	}
	98
	99	/*
	100	* If we have clusters <= 1 and CPUs <= 8 in cluster 0, then flat mode,
	101	* else if max_cluster <= 4 and cluster_cnt[15] == 0, clustered logical
	102	* else physical mode.
	103	* (We don't use lowest priority delivery + HW APIC IRQ steering, so
	104	* can ignore the clustered logical case and go straight to physical.)
	105	*/
	106	if (clusters <= 1 && max_cluster <= 8 && cluster_cnt[0] == max_cluster)
	107	genapic = &apic_flat;
	108	else
	109	genapic = &apic_cluster;
	110
	111	print:
	112	printk(KERN_INFO "Setting APIC routing to %s\n", genapic->name);
	113	}
	114
	115	/* Same for both flat and clustered. */
	116
	117	void send_IPI_self(int vector)
	118	{
	119	__send_IPI_shortcut(APIC_DEST_SELF, vector, APIC_DEST_PHYSICAL);
	120	}