x86/platform/UV: Add references to access fixed UV4A HUB MMRs

Add references to enable access to fixed UV4A (rev2) HUB MMRs.

Signed-off-by: Mike Travis <mike.travis@hpe.com>
Acked-by: Andrew Banman <abanman@hpe.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dimitri Sivanich <sivanich@hpe.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <rja@hpe.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1515440405-20880-4-git-send-email-mike.travis@hpe.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/include/asm/uv/uv_hub.h

@@ -241,6 +241,7 @@ static inline int uv_hub_info_check(int version)
 #define UV2_HUB_REVISION_BASE		3
 #define UV3_HUB_REVISION_BASE		5
 #define UV4_HUB_REVISION_BASE		7
+#define UV4A_HUB_REVISION_BASE		8	/* UV4 (fixed) rev 2 */
 
 #ifdef	UV1_HUB_IS_SUPPORTED
 static inline int is_uv1_hub(void)
@@ -280,6 +281,19 @@ static inline int is_uv3_hub(void)
 }
 #endif
 
+/* First test "is UV4A", then "is UV4" */
+#ifdef	UV4A_HUB_IS_SUPPORTED
+static inline int is_uv4a_hub(void)
+{
+	return (uv_hub_info->hub_revision >= UV4A_HUB_REVISION_BASE);
+}
+#else
+static inline int is_uv4a_hub(void)
+{
+	return 0;
+}
+#endif
+
 #ifdef	UV4_HUB_IS_SUPPORTED
 static inline int is_uv4_hub(void)
 {

arch/x86/include/asm/uv/uv_mmrs.h

@@ -99,6 +99,7 @@
 #define UV2_HUB_IS_SUPPORTED	1
 #define UV3_HUB_IS_SUPPORTED	1
 #define UV4_HUB_IS_SUPPORTED	1
+#define UV4A_HUB_IS_SUPPORTED	1
 
 /* Error function to catch undefined references */
 extern unsigned long uv_undefined(char *str);

arch/x86/kernel/apic/x2apic_uv_x.c

@@ -137,6 +137,8 @@ static int __init early_get_pnodeid(void)
 	case UV3_HUB_PART_NUMBER_X:
 		uv_min_hub_revision_id += UV3_HUB_REVISION_BASE;
 		break;
+
+	/* Update: UV4A has only a modified revision to indicate HUB fixes */
 	case UV4_HUB_PART_NUMBER:
 		uv_min_hub_revision_id += UV4_HUB_REVISION_BASE - 1;
 		uv_cpuid.gnode_shift = 2; /* min partition is 4 sockets */