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authorAndi Kleen <ak@suse.de>2006-04-07 19:49:45 +0200
committerLinus Torvalds <torvalds@g5.osdl.org>2006-04-09 11:53:51 -0700
commit95d769aaf47abfc77b600631403ff5af6c990cff (patch)
tree738fff854613a086e7c1ad04074fa596b8554760 /arch/i386/kernel/apic.c
parentd1530d82e02fd96d4634a6d6f6538c8b778c43af (diff)
[PATCH] i386: Consolidate modern APIC handling
AMD systems have a modern APIC that supports 8 bit IDs, but don't have a XAPIC version number. Add a new "modern_apic" subfunction that handles this correctly and use it (nearly) everywhere where XAPIC is tested for. I removed one wart: the code specified that external APICs would use an 8bit APIC ID. But I checked a real 82093 data sheet and it says clearly that they only use 4bit. So I removed this special case since it would a bit awkward to implement now. I removed the valid APIC tests in mptable parsing completely. On any modern system they only check against the full field width (8bit) anyways and are no-ops. This also fixes them doing the wrong thing on >8 core Opterons. This makes i386 boot again on 16 core Opterons. Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'arch/i386/kernel/apic.c')
-rw-r--r--arch/i386/kernel/apic.c23
1 files changed, 16 insertions, 7 deletions
diff --git a/arch/i386/kernel/apic.c b/arch/i386/kernel/apic.c
index 6273bf74c20..254cee9f0b7 100644
--- a/arch/i386/kernel/apic.c
+++ b/arch/i386/kernel/apic.c
@@ -62,6 +62,18 @@ int apic_verbosity;
static void apic_pm_activate(void);
+int modern_apic(void)
+{
+ unsigned int lvr, version;
+ /* AMD systems use old APIC versions, so check the CPU */
+ if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
+ boot_cpu_data.x86 >= 0xf)
+ return 1;
+ lvr = apic_read(APIC_LVR);
+ version = GET_APIC_VERSION(lvr);
+ return version >= 0x14;
+}
+
/*
* 'what should we do if we get a hw irq event on an illegal vector'.
* each architecture has to answer this themselves.
@@ -119,10 +131,7 @@ void enable_NMI_through_LVT0 (void * dummy)
int get_physical_broadcast(void)
{
- unsigned int lvr, version;
- lvr = apic_read(APIC_LVR);
- version = GET_APIC_VERSION(lvr);
- if (!APIC_INTEGRATED(version) || version >= 0x14)
+ if (modern_apic())
return 0xff;
else
return 0xf;
@@ -349,9 +358,9 @@ int __init verify_local_APIC(void)
void __init sync_Arb_IDs(void)
{
- /* Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1 */
- unsigned int ver = GET_APIC_VERSION(apic_read(APIC_LVR));
- if (ver >= 0x14) /* P4 or higher */
+ /* Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1
+ And not needed on AMD */
+ if (modern_apic())
return;
/*
* Wait for idle.