diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/x86_64/kernel/genapic.c |
Linux-2.6.12-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!
Diffstat (limited to 'arch/x86_64/kernel/genapic.c')
-rw-r--r-- | arch/x86_64/kernel/genapic.c | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/arch/x86_64/kernel/genapic.c b/arch/x86_64/kernel/genapic.c new file mode 100644 index 00000000000..d2c42fb99cb --- /dev/null +++ b/arch/x86_64/kernel/genapic.c @@ -0,0 +1,89 @@ +/* + * 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> + +/* which logical CPU number maps to which CPU (physical APIC ID) */ +u8 x86_cpu_to_apicid[NR_CPUS] = { [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; + +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]; + + if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) { + /* AMD always uses flat mode right now */ + genapic = &apic_flat; + goto print; + } + + memset(cluster_cnt, 0, sizeof(cluster_cnt)); + + for (i = 0; i < NR_CPUS; i++) { + id = bios_cpu_apicid[i]; + if (id != BAD_APICID) + cluster_cnt[APIC_CLUSTERID(id)]++; + } + + 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); +} |