x86/platform/uv: Fix calculation of Global Physical Address

The calculation of the global physical address (GPA) on UV4 is
incorrect.  The gnode_extra/upper global offset should only be
applied for fixed address space systems (UV1..3).

Tested-by: John Estabrook <john.estabrook@hpe.com>
Signed-off-by: Mike Travis <mike.travis@hpe.com>
Cc: Dimitri Sivanich <dimitri.sivanich@hpe.com>
Cc: John Estabrook <estabrook@sgi.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <russ.anderson@hpe.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170321231646.667689538@asylum.americas.sgi.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

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

@@ -485,15 +485,17 @@ static inline unsigned long uv_soc_phys_ram_to_gpa(unsigned long paddr)
 
 	if (paddr < uv_hub_info->lowmem_remap_top)
 		paddr |= uv_hub_info->lowmem_remap_base;
-	paddr |= uv_hub_info->gnode_upper;
-	if (m_val)
+
+	if (m_val) {
+		paddr |= uv_hub_info->gnode_upper;
 		paddr = ((paddr << uv_hub_info->m_shift)
 						>> uv_hub_info->m_shift) |
 			((paddr >> uv_hub_info->m_val)
 						<< uv_hub_info->n_lshift);
-	else
+	} else {
 		paddr |= uv_soc_phys_ram_to_nasid(paddr)
 						<< uv_hub_info->gpa_shift;
+	}
 	return paddr;
 }
 

arch/x86/kernel/apic/x2apic_uv_x.c

@@ -1105,7 +1105,8 @@ void __init uv_init_hub_info(struct uv_hub_info_s *hi)
 	node_id.v		= uv_read_local_mmr(UVH_NODE_ID);
 	uv_cpuid.gnode_shift	= max_t(unsigned int, uv_cpuid.gnode_shift, mn.n_val);
 	hi->gnode_extra		= (node_id.s.node_id & ~((1 << uv_cpuid.gnode_shift) - 1)) >> 1;
-	hi->gnode_upper		= (unsigned long)hi->gnode_extra << mn.m_val;
+	if (mn.m_val)
+		hi->gnode_upper	= (u64)hi->gnode_extra << mn.m_val;
 
 	if (uv_gp_table) {
 		hi->global_mmr_base	= uv_gp_table->mmr_base;