x86/UV: Set n_lshift based on GAM_GR_CONFIG MMR for UV3

The value of n_lshift for UV is currently set based on the
socket m_val.

For UV3, set the n_lshift value based on the GAM_GR_CONFIG MMR.
This will allow bios to control the n_lshift value independent
of the socket m_val. Then n_lshift can be assigned a fixed value
across a multi-partition system, allowing for a fixed common
global physical address format that is independent of socket
m_val.

Cleanup unneeded macros.

Signed-off-by: Dimitri Sivanich <sivanich@sgi.com>
Link: http://lkml.kernel.org/r/20140331143700.GB29916@sgi.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 21 insertions, 5 deletions

diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c
index 7834389..293b41d 100644
--- a/arch/x86/kernel/apic/x2apic_uv_x.c
+++ b/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -5,7 +5,7 @@
  *
  * SGI UV APIC functions (note: not an Intel compatible APIC)
  *
- * Copyright (C) 2007-2013 Silicon Graphics, Inc. All rights reserved.
+ * Copyright (C) 2007-2014 Silicon Graphics, Inc. All rights reserved.
  */
 #include <linux/cpumask.h>
 #include <linux/hardirq.h>
@@ -440,6 +440,20 @@ static __initdata struct redir_addr redir_addrs[] = {
 	{UVH_RH_GAM_ALIAS210_REDIRECT_CONFIG_2_MMR, UVH_RH_GAM_ALIAS210_OVERLAY_CONFIG_2_MMR},
 };
 
+static unsigned char get_n_lshift(int m_val)
+{
+	union uv3h_gr0_gam_gr_config_u m_gr_config;
+
+	if (is_uv1_hub())
+		return m_val;
+
+	if (is_uv2_hub())
+		return m_val == 40 ? 40 : 39;
+
+	m_gr_config.v = uv_read_local_mmr(UV3H_GR0_GAM_GR_CONFIG);
+	return m_gr_config.s3.m_skt;
+}
+
 static __init void get_lowmem_redirect(unsigned long *base, unsigned long *size)
 {
 	union uvh_rh_gam_alias210_overlay_config_2_mmr_u alias;
@@ -849,6 +863,7 @@ void __init uv_system_init(void)
 	int gnode_extra, min_pnode = 999999, max_pnode = -1;
 	unsigned long mmr_base, present, paddr;
 	unsigned short pnode_mask;
+	unsigned char n_lshift;
 	char *hub = (is_uv1_hub() ? "UV1" :
 		    (is_uv2_hub() ? "UV2" :
 				    "UV3"));
@@ -860,6 +875,7 @@ void __init uv_system_init(void)
 	m_val = m_n_config.s.m_skt;
 	n_val = m_n_config.s.n_skt;
 	pnode_mask = (1 << n_val) - 1;
+	n_lshift = get_n_lshift(m_val);
 	mmr_base =
 	    uv_read_local_mmr(UVH_RH_GAM_MMR_OVERLAY_CONFIG_MMR) &
 	    ~UV_MMR_ENABLE;
@@ -867,8 +883,9 @@ void __init uv_system_init(void)
 	node_id.v = uv_read_local_mmr(UVH_NODE_ID);
 	gnode_extra = (node_id.s.node_id & ~((1 << n_val) - 1)) >> 1;
 	gnode_upper = ((unsigned long)gnode_extra  << m_val);
-	pr_info("UV: N:%d M:%d pnode_mask:0x%x gnode_upper/extra:0x%lx/0x%x\n",
-			n_val, m_val, pnode_mask, gnode_upper, gnode_extra);
+	pr_info("UV: N:%d M:%d pnode_mask:0x%x gnode_upper/extra:0x%lx/0x%x n_lshift 0x%x\n",
+			n_val, m_val, pnode_mask, gnode_upper, gnode_extra,
+			n_lshift);
 
 	pr_info("UV: global MMR base 0x%lx\n", mmr_base);
 
@@ -935,8 +952,7 @@ void __init uv_system_init(void)
 		uv_cpu_hub_info(cpu)->hub_revision = uv_hub_info->hub_revision;
 
 		uv_cpu_hub_info(cpu)->m_shift = 64 - m_val;
-		uv_cpu_hub_info(cpu)->n_lshift = is_uv2_1_hub() ?
-				(m_val == 40 ? 40 : 39) : m_val;
+		uv_cpu_hub_info(cpu)->n_lshift = n_lshift;
 
 		pnode = uv_apicid_to_pnode(apicid);
 		blade = boot_pnode_to_blade(pnode);