x86: Add apic->x86_32_early_logical_apicid()
On x86_32, the mapping between cpu and logical apic ID differs
depending on the specific apic implementation in use. The
mapping is initialized while bringing up CPUs; however, this
makes early inits ignore memory topology.
Add a x86_32 specific apic->x86_32_early_logical_apicid() which
is called early during boot to query the mapping. The mapping
is later verified against the result of init_apic_ldr(). The
method is allowed to return BAD_APICID if it can't be determined
early.
noop variant which always returns BAD_APICID is implemented and
added to all x86_32 apic implementations.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: eric.dumazet@gmail.com
Cc: yinghai@kernel.org
Cc: brgerst@gmail.com
Cc: gorcunov@gmail.com
Cc: penberg@kernel.org
Cc: shaohui.zheng@intel.com
Cc: rientjes@google.com
LKML-Reference: <1295789862-25482-8-git-send-email-tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h
index d1aa0c3..efb073b 100644
--- a/arch/x86/include/asm/apic.h
+++ b/arch/x86/include/asm/apic.h
@@ -354,6 +354,20 @@
void (*icr_write)(u32 low, u32 high);
void (*wait_icr_idle)(void);
u32 (*safe_wait_icr_idle)(void);
+
+#ifdef CONFIG_X86_32
+ /*
+ * Called very early during boot from get_smp_config(). It should
+ * return the logical apicid. x86_[bios]_cpu_to_apicid is
+ * initialized before this function is called.
+ *
+ * If logical apicid can't be determined that early, the function
+ * may return BAD_APICID. Logical apicid will be configured after
+ * init_apic_ldr() while bringing up CPUs. Note that NUMA affinity
+ * won't be applied properly during early boot in this case.
+ */
+ int (*x86_32_early_logical_apicid)(int cpu);
+#endif
};
/*
@@ -501,6 +515,11 @@
extern struct apic apic_default;
+static inline int noop_x86_32_early_logical_apicid(int cpu)
+{
+ return BAD_APICID;
+}
+
/*
* Set up the logical destination ID.
*