x86/platform/UV: Build GAM reference tables

An aspect of the UV4 system architecture changes involve changing the
way sockets, nodes, and pnodes are translated between one another.
Decode the information from the BIOS provided EFI system table to build
the needed conversion tables.

Tested-by: Dimitri Sivanich <sivanich@sgi.com>
Tested-by: John Estabrook <estabrook@sgi.com>
Tested-by: Gary Kroening <gfk@sgi.com>
Tested-by: Nathan Zimmer <nzimmer@sgi.com>
Signed-off-by: Mike Travis <travis@sgi.com>
Reviewed-by: Dimitri Sivanich <sivanich@sgi.com>
Cc: Andrew Banman <abanman@sgi.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <rja@sgi.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20160429215405.673495324@asylum.americas.sgi.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

2 files changed, 155 insertions, 2 deletions

diff --git a/arch/x86/include/asm/uv/uv_hub.h b/arch/x86/include/asm/uv/uv_hub.h
index 1978e4b8dcff..6900161e1684 100644
--- a/arch/x86/include/asm/uv/uv_hub.h
+++ b/arch/x86/include/asm/uv/uv_hub.h
@@ -149,6 +149,9 @@ struct uv_hub_info_s {
         unsigned long           global_mmr_base;
         unsigned long           global_mmr_shift;
         unsigned long           gpa_mask;
+        unsigned short          *socket_to_node;
+        unsigned short          *socket_to_pnode;
+        unsigned short          *pnode_to_socket;
         unsigned short          min_socket;
         unsigned short          min_pnode;
         unsigned char           hub_revision;
@@ -481,10 +484,21 @@ static inline void *uv_pnode_offset_to_vaddr(int pnode, unsigned long offset)
         return __va(((unsigned long)pnode << uv_hub_info->m_val) | offset);
 }
 
-/* Extract a PNODE from an APICID (full apicid, not processor subset) */
+/* Convert socket to node */
+static inline int uv_socket_to_node(int socket)
+{
+        unsigned short *s2nid = uv_hub_info->socket_to_node;
+
+        return s2nid ? s2nid[socket - uv_hub_info->min_socket] : socket;
+}
+
+/* Extract/Convert a PNODE from an APICID (full apicid, not processor subset) */
 static inline int uv_apicid_to_pnode(int apicid)
 {
-        return (apicid >> uv_hub_info->apic_pnode_shift);
+        int pnode = apicid >> uv_hub_info->apic_pnode_shift;
+        unsigned short *s2pn = uv_hub_info->socket_to_pnode;
+
+        return s2pn ? s2pn[pnode - uv_hub_info->min_socket] : pnode;
 }
 
 /* Convert an apicid to the socket number on the blade */
diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c
index 128f47e7b018..259c3dd889c6 100644
--- a/arch/x86/kernel/apic/x2apic_uv_x.c
+++ b/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -307,6 +307,9 @@ static __initdata unsigned short _min_socket, _max_socket;
 static __initdata unsigned short _min_pnode, _max_pnode, _gr_table_len;
 static __initdata struct uv_gam_range_entry *uv_gre_table;
 static __initdata struct uv_gam_parameters *uv_gp_table;
+static __initdata unsigned short *_socket_to_node;
+static __initdata unsigned short *_socket_to_pnode;
+static __initdata unsigned short *_pnode_to_socket;
 #define SOCK_EMPTY      ((unsigned short)~0)
 
 extern int uv_hub_info_version(void)
@@ -985,6 +988,10 @@ void __init uv_init_hub_info(struct uv_hub_info_s *hub_info)
         hub_info->hub_revision = uv_hub_info->hub_revision;
         hub_info->pnode_mask = uv_cpuid.pnode_mask;
         hub_info->min_pnode = _min_pnode;
+        hub_info->min_socket = _min_socket;
+        hub_info->pnode_to_socket = _pnode_to_socket;
+        hub_info->socket_to_node = _socket_to_node;
+        hub_info->socket_to_pnode = _socket_to_pnode;
         hub_info->gpa_mask = mn.m_val ?
                 (1UL << (mn.m_val + mn.n_val)) - 1 :
                 (1UL << uv_cpuid.gpa_shift) - 1;
@@ -1171,6 +1178,137 @@ static __init void boot_init_possible_blades(struct uv_hub_info_s *hub_info)
         }
 }
 
+static void __init build_socket_tables(void)
+{
+        struct uv_gam_range_entry *gre = uv_gre_table;
+        int num, nump;
+        int cpu, i, lnid;
+        int minsock = _min_socket;
+        int maxsock = _max_socket;
+        int minpnode = _min_pnode;
+        int maxpnode = _max_pnode;
+        size_t bytes;
+
+        if (!gre) {
+                if (is_uv1_hub() || is_uv2_hub() || is_uv3_hub()) {
+                        pr_info("UV: No UVsystab socket table, ignoring\n");
+                        return;         /* not required */
+                }
+                pr_crit(
+                "UV: Error: UVsystab address translations not available!\n");
+                BUG();
+        }
+
+        /* build socket id -> node id, pnode */
+        num = maxsock - minsock + 1;
+        bytes = num * sizeof(_socket_to_node[0]);
+        _socket_to_node = kmalloc(bytes, GFP_KERNEL);
+        _socket_to_pnode = kmalloc(bytes, GFP_KERNEL);
+
+        nump = maxpnode - minpnode + 1;
+        bytes = nump * sizeof(_pnode_to_socket[0]);
+        _pnode_to_socket = kmalloc(bytes, GFP_KERNEL);
+        BUG_ON(!_socket_to_node || !_socket_to_pnode || !_pnode_to_socket);
+
+        for (i = 0; i < num; i++)
+                _socket_to_node[i] = _socket_to_pnode[i] = SOCK_EMPTY;
+
+        for (i = 0; i < nump; i++)
+                _pnode_to_socket[i] = SOCK_EMPTY;
+
+        /* fill in pnode/node/addr conversion list values */
+        pr_info("UV: GAM Building socket/pnode/pxm conversion tables\n");
+        for (; gre->type != UV_GAM_RANGE_TYPE_UNUSED; gre++) {
+                if (gre->type == UV_GAM_RANGE_TYPE_HOLE)
+                        continue;
+                i = gre->sockid - minsock;
+                if (_socket_to_pnode[i] != SOCK_EMPTY)
+                        continue;       /* duplicate */
+                _socket_to_pnode[i] = gre->pnode;
+                _socket_to_node[i] = gre->pxm;
+
+                i = gre->pnode - minpnode;
+                _pnode_to_socket[i] = gre->sockid;
+
+                pr_info(
+                "UV: sid:%02x type:%d nasid:%04x pn:%02x pxm:%2d pn2s:%2x\n",
+                        gre->sockid, gre->type, gre->nasid,
+                        _socket_to_pnode[gre->sockid - minsock],
+                        _socket_to_node[gre->sockid - minsock],
+                        _pnode_to_socket[gre->pnode - minpnode]);
+        }
+
+        /* check socket -> node values */
+        lnid = -1;
+        for_each_present_cpu(cpu) {
+                int nid = cpu_to_node(cpu);
+                int apicid, sockid;
+
+                if (lnid == nid)
+                        continue;
+                lnid = nid;
+                apicid = per_cpu(x86_cpu_to_apicid, cpu);
+                sockid = apicid >> uv_cpuid.socketid_shift;
+                i = sockid - minsock;
+
+                if (nid != _socket_to_node[i]) {
+                        pr_warn(
+                        "UV: %02x: type:%d socket:%02x PXM:%02x != node:%2d\n",
+                                i, sockid, gre->type, _socket_to_node[i], nid);
+                        _socket_to_node[i] = nid;
+                }
+        }
+
+        /* Setup physical blade to pnode translation from GAM Range Table */
+        bytes = num_possible_nodes() * sizeof(_node_to_pnode[0]);
+        _node_to_pnode = kmalloc(bytes, GFP_KERNEL);
+        BUG_ON(!_node_to_pnode);
+
+        for (lnid = 0; lnid < num_possible_nodes(); lnid++) {
+                unsigned short sockid;
+
+                for (sockid = minsock; sockid <= maxsock; sockid++) {
+                        if (lnid == _socket_to_node[sockid - minsock]) {
+                                _node_to_pnode[lnid] =
+                                        _socket_to_pnode[sockid - minsock];
+                                break;
+                        }
+                }
+                if (sockid > maxsock) {
+                        pr_err("UV: socket for node %d not found!\n", lnid);
+                        BUG();
+                }
+        }
+
+        /*
+         * If socket id == pnode or socket id == node for all nodes,
+         *   system runs faster by removing corresponding conversion table.
+         */
+        pr_info("UV: Checking socket->node/pnode for identity maps\n");
+        if (minsock == 0) {
+                for (i = 0; i < num; i++)
+                        if (_socket_to_node[i] == SOCK_EMPTY ||
+                                i != _socket_to_node[i])
+                                break;
+                if (i >= num) {
+                        kfree(_socket_to_node);
+                        _socket_to_node = NULL;
+                        pr_info("UV: 1:1 socket_to_node table removed\n");
+                }
+        }
+        if (minsock == minpnode) {
+                for (i = 0; i < num; i++)
+                        if (_socket_to_pnode[i] != SOCK_EMPTY &&
+                                _socket_to_pnode[i] != i + minpnode)
+                                break;
+                if (i >= num) {
+                        kfree(_socket_to_pnode);
+                        _socket_to_pnode = NULL;
+                        pr_info("UV: 1:1 socket_to_pnode table removed\n");
+                }
+        }
+}
+
 void __init uv_system_init(void)
 {
         struct uv_hub_info_s hub_info = {0};
@@ -1193,6 +1331,7 @@ void __init uv_system_init(void)
 
         uv_bios_init();                 /* get uv_systab for decoding */
         decode_uv_systab();
+        build_socket_tables();
         uv_init_hub_info(&hub_info);
         uv_possible_blades = num_possible_nodes();
         if (!_node_to_pnode)