[CELL] cell: indexing of SPUs based on firmware vicinity properties

This patch links spus according to their physical position using
information provided by the firmware through a special vicinity
device-tree property. This property is present in current version
of Malta firmware.

Example of vicinity properties for a node in Malta:

Node:        Vicinity property contains phandles of:
spe@0        [ spe@100000 , mic-tm@50a000 ]
spe@100000   [ spe@0      , spe@200000    ]
spe@200000   [ spe@100000 , spe@300000    ]
spe@300000   [ spe@200000 , bif0@512000   ]
spe@80000    [ spe@180000 , mic-tm@50a000 ]
spe@180000   [ spe@80000  , spe@280000    ]
spe@280000   [ spe@180000 , spe@380000    ]
spe@380000   [ spe@280000 , bif0@512000   ]

Only spe@* have a vicinity property (e.g., bif0@512000 and
mic-tm@50a000 do not have it).

Signed-off-by: Andre Detsch <adetsch@br.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>

1 files changed, 89 insertions, 1 deletions

diff --git a/arch/powerpc/platforms/cell/spu_base.c b/arch/powerpc/platforms/cell/spu_base.c
index 5f399313b472..03b4a8eb9044 100644
--- a/arch/powerpc/platforms/cell/spu_base.c
+++ b/arch/powerpc/platforms/cell/spu_base.c
@@ -724,6 +724,92 @@ static int of_has_vicinity(void)
         return of_find_property(spu_devnode(spu), "vicinity", NULL) != NULL;
 }
 
+static struct spu *aff_devnode_spu(int cbe, struct device_node *dn)
+{
+        struct spu *spu;
+
+        list_for_each_entry(spu, &cbe_spu_info[cbe].spus, cbe_list)
+                if (spu_devnode(spu) == dn)
+                        return spu;
+        return NULL;
+}
+
+static struct spu *
+aff_node_next_to(int cbe, struct device_node *target, struct device_node *avoid)
+{
+        struct spu *spu;
+        const phandle *vic_handles;
+        int lenp, i;
+
+        list_for_each_entry(spu, &cbe_spu_info[cbe].spus, cbe_list) {
+                if (spu_devnode(spu) == avoid)
+                        continue;
+                vic_handles = get_property(spu_devnode(spu), "vicinity", &lenp);
+                for (i=0; i < (lenp / sizeof(phandle)); i++) {
+                        if (vic_handles[i] == target->linux_phandle)
+                                return spu;
+                }
+        }
+        return NULL;
+}
+
+static void init_aff_fw_vicinity_node(int cbe)
+{
+        struct spu *spu, *last_spu;
+        struct device_node *vic_dn, *last_spu_dn;
+        phandle avoid_ph;
+        const phandle *vic_handles;
+        const char *name;
+        int lenp, i, added, mem_aff;
+
+        last_spu = list_entry(cbe_spu_info[cbe].spus.next, struct spu, cbe_list);
+        avoid_ph = 0;
+        for (added = 1; added < cbe_spu_info[cbe].n_spus; added++) {
+                last_spu_dn = spu_devnode(last_spu);
+                vic_handles = get_property(last_spu_dn, "vicinity", &lenp);
+
+                for (i = 0; i < (lenp / sizeof(phandle)); i++) {
+                        if (vic_handles[i] == avoid_ph)
+                                continue;
+
+                        vic_dn = of_find_node_by_phandle(vic_handles[i]);
+                        if (!vic_dn)
+                                continue;
+
+                        name = get_property(vic_dn, "name", NULL);
+                        if (strcmp(name, "spe") == 0) {
+                                spu = aff_devnode_spu(cbe, vic_dn);
+                                avoid_ph = last_spu_dn->linux_phandle;
+                        }
+                        else {
+                                mem_aff = strcmp(name, "mic-tm") == 0;
+                                spu = aff_node_next_to(cbe, vic_dn, last_spu_dn);
+                                if (!spu)
+                                        continue;
+                                if (mem_aff) {
+                                        last_spu->has_mem_affinity = 1;
+                                        spu->has_mem_affinity = 1;
+                                }
+                                avoid_ph = vic_dn->linux_phandle;
+                        }
+                        list_add_tail(&spu->aff_list, &last_spu->aff_list);
+                        last_spu = spu;
+                        break;
+                }
+        }
+}
+
+static void init_aff_fw_vicinity(void)
+{
+        int cbe;
+
+        /* sets has_mem_affinity for each spu, as long as the
+         * spu->aff_list list, linking each spu to its neighbors
+         */
+        for (cbe = 0; cbe < MAX_NUMNODES; cbe++)
+                init_aff_fw_vicinity_node(cbe);
+}
+
 static int __init init_spu_base(void)
 {
         int i, ret = 0;
@@ -765,7 +851,9 @@ static int __init init_spu_base(void)
         crash_register_spus(&spu_full_list);
         spu_add_sysdev_attr(&attr_stat);
 
-        if (!of_has_vicinity()) {
+        if (of_has_vicinity()) {
+                init_aff_fw_vicinity();
+        } else {
                 long root = of_get_flat_dt_root();
                 if (of_flat_dt_is_compatible(root, "IBM,CPBW-1.0"))
                         init_aff_QS20_harcoded();