x86: SGI UV: Fix writes to led registers on remote uv hubs

The wrong address was being used to write the SCIR led regs on
remote hubs.  Also, there was an inconsistency between how BIOS
and the kernel indexed these regs.  Standardize on using the
lower 6 bits of the APIC ID as the index.

This patch fixes the problem of writing to an errant address to
a cpu # >= 64.

Signed-off-by: Mike Travis <travis@sgi.com>
Reviewed-by: Jack Steiner <steiner@sgi.com>
Cc: Robin Holt <holt@sgi.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: stable@kernel.org
LKML-Reference: <4B3922F9.3060905@sgi.com>
[ v2: fix a number of annoying checkpatch artifacts and whitespace noise ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 6 insertions, 6 deletions

diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c
index d56b0efb2057..5f92494dab61 100644
--- a/arch/x86/kernel/apic/x2apic_uv_x.c
+++ b/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -629,8 +629,10 @@ void __init uv_system_init(void)
         uv_rtc_init();
 
         for_each_present_cpu(cpu) {
+                int apicid = per_cpu(x86_cpu_to_apicid, cpu);
+
                 nid = cpu_to_node(cpu);
-                pnode = uv_apicid_to_pnode(per_cpu(x86_cpu_to_apicid, cpu));
+                pnode = uv_apicid_to_pnode(apicid);
                 blade = boot_pnode_to_blade(pnode);
                 lcpu = uv_blade_info[blade].nr_possible_cpus;
                 uv_blade_info[blade].nr_possible_cpus++;
@@ -651,15 +653,13 @@ void __init uv_system_init(void)
                 uv_cpu_hub_info(cpu)->gnode_extra = gnode_extra;
                 uv_cpu_hub_info(cpu)->global_mmr_base = mmr_base;
                 uv_cpu_hub_info(cpu)->coherency_domain_number = sn_coherency_id;
-                uv_cpu_hub_info(cpu)->scir.offset = SCIR_LOCAL_MMR_BASE + lcpu;
+                uv_cpu_hub_info(cpu)->scir.offset = uv_scir_offset(apicid);
                 uv_node_to_blade[nid] = blade;
                 uv_cpu_to_blade[cpu] = blade;
                 max_pnode = max(pnode, max_pnode);
 
-                printk(KERN_DEBUG "UV: cpu %d, apicid 0x%x, pnode %d, nid %d, "
-                        "lcpu %d, blade %d\n",
-                        cpu, per_cpu(x86_cpu_to_apicid, cpu), pnode, nid,
-                        lcpu, blade);
+                printk(KERN_DEBUG "UV: cpu %d, apicid 0x%x, pnode %d, nid %d, lcpu %d, blade %d\n",
+                        cpu, apicid, pnode, nid, lcpu, blade);
         }
 
         /* Add blade/pnode info for nodes without cpus */