x86: Add NumaChip support

Adds support for Numascale NumaChip large-SMP systems. It is
needed to enable the booting of more than ~168 cores.

v2:
 - [Steffen] enumerate only accessible northbridges
 - [Daniel] rediffed and validated against 3.1-rc10

v3:
 - [Daniel] use x86_init core numbering override
 - [Daniel] cleanups as per feedback

v4:
 - [Daniel] use updated x86_cpuinit override

v5:
 - drop disabling interrupts locally, as ISR write is atomic; drop delay
 - added read-mostly annotations where appropriate
 - require CONFIG_SMP, so drop conditional path

Workload tested on 96 cores/16 sockets.

Signed-off-by: Steffen Persvold <sp@numascale.com>
Signed-off-by: Daniel J Blueman <daniel@numascale-asia.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Link: http://lkml.kernel.org/r/1323101246-2400-1-git-send-email-daniel@numascale-asia.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 13 insertions, 0 deletions

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index cb9a1044a77..7b9eaa1ae10 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -343,6 +343,7 @@ config X86_EXTENDED_PLATFORM
 
           If you enable this option then you'll be able to select support
           for the following (non-PC) 64 bit x86 platforms:
+                Numascale NumaChip
                 ScaleMP vSMP
                 SGI Ultraviolet
 
@@ -351,6 +352,18 @@ config X86_EXTENDED_PLATFORM
 endif
 # This is an alphabetically sorted list of 64 bit extended platforms
 # Please maintain the alphabetic order if and when there are additions
+config X86_NUMACHIP
+        bool "Numascale NumaChip"
+        depends on X86_64
+        depends on X86_EXTENDED_PLATFORM
+        depends on NUMA
+        depends on SMP
+        depends on X86_X2APIC
+        depends on !EDAC_AMD64
+        ---help---
+          Adds support for Numascale NumaChip large-SMP systems. Needed to
+          enable more than ~168 cores.
+          If you don't have one of these, you should say N here.
 
 config X86_VSMP
         bool "ScaleMP vSMP"