powerpc+of: Add of node/property notification chain for adds and removes

This patch moves the notification chain for updates to the device tree
from the powerpc/pseries code to the base OF code. This makes this
functionality available to all architectures.

Additionally the notification chain is updated to allow notifications
for property add/remove/update. To make this work a pointer to a new
struct (of_prop_reconfig) is passed to the routines in the notification chain.
The of_prop_reconfig property contains a pointer to the node containing the
property and a pointer to the property itself. In the case of property
updates, the property pointer refers to the new property.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 43 insertions, 17 deletions

diff --git a/arch/powerpc/platforms/pseries/hotplug-memory.c b/arch/powerpc/platforms/pseries/hotplug-memory.c
index ecdb0a6b3171..2372c609fa2b 100644
--- a/arch/powerpc/platforms/pseries/hotplug-memory.c
+++ b/arch/powerpc/platforms/pseries/hotplug-memory.c
@@ -16,7 +16,6 @@
 
 #include <asm/firmware.h>
 #include <asm/machdep.h>
-#include <asm/pSeries_reconfig.h>
 #include <asm/sparsemem.h>
 
 static unsigned long get_memblock_size(void)
@@ -187,42 +186,69 @@ static int pseries_add_memory(struct device_node *np)
         return (ret < 0) ? -EINVAL : 0;
 }
 
-static int pseries_drconf_memory(unsigned long *base, unsigned int action)
+static int pseries_update_drconf_memory(struct of_prop_reconfig *pr)
 {
+        struct of_drconf_cell *new_drmem, *old_drmem;
         unsigned long memblock_size;
-        int rc;
+        u32 entries;
+        u32 *p;
+        int i, rc = -EINVAL;
 
         memblock_size = get_memblock_size();
         if (!memblock_size)
                 return -EINVAL;
 
-        if (action == PSERIES_DRCONF_MEM_ADD) {
-                rc = memblock_add(*base, memblock_size);
-                rc = (rc < 0) ? -EINVAL : 0;
-        } else if (action == PSERIES_DRCONF_MEM_REMOVE) {
-                rc = pseries_remove_memblock(*base, memblock_size);
-        } else {
-                rc = -EINVAL;
+        p = (u32 *)of_get_property(pr->dn, "ibm,dynamic-memory", NULL);
+        if (!p)
+                return -EINVAL;
+
+        /* The first int of the property is the number of lmb's described
+         * by the property. This is followed by an array of of_drconf_cell
+         * entries. Get the niumber of entries and skip to the array of
+         * of_drconf_cell's.
+         */
+        entries = *p++;
+        old_drmem = (struct of_drconf_cell *)p;
+
+        p = (u32 *)pr->prop->value;
+        p++;
+        new_drmem = (struct of_drconf_cell *)p;
+
+        for (i = 0; i < entries; i++) {
+                if ((old_drmem[i].flags & DRCONF_MEM_ASSIGNED) &&
+                    (!(new_drmem[i].flags & DRCONF_MEM_ASSIGNED))) {
+                        rc = pseries_remove_memblock(old_drmem[i].base_addr,
+                                                     memblock_size);
+                        break;
+                } else if ((!(old_drmem[i].flags & DRCONF_MEM_ASSIGNED)) &&
+                           (new_drmem[i].flags & DRCONF_MEM_ASSIGNED)) {
+                        rc = memblock_add(old_drmem[i].base_addr,
+                                          memblock_size);
+                        rc = (rc < 0) ? -EINVAL : 0;
+                        break;
+                }
         }
 
         return rc;
 }
 
 static int pseries_memory_notifier(struct notifier_block *nb,
-                                unsigned long action, void *node)
+                                   unsigned long action, void *node)
 {
+        struct of_prop_reconfig *pr;
         int err = 0;
 
         switch (action) {
-        case PSERIES_RECONFIG_ADD:
+        case OF_RECONFIG_ATTACH_NODE:
                 err = pseries_add_memory(node);
                 break;
-        case PSERIES_RECONFIG_REMOVE:
+        case OF_RECONFIG_DETACH_NODE:
                 err = pseries_remove_memory(node);
                 break;
-        case PSERIES_DRCONF_MEM_ADD:
-        case PSERIES_DRCONF_MEM_REMOVE:
-                err = pseries_drconf_memory(node, action);
+        case OF_RECONFIG_UPDATE_PROPERTY:
+                pr = (struct of_prop_reconfig *)node;
+                if (!strcmp(pr->prop->name, "ibm,dynamic-memory"))
+                        err = pseries_update_drconf_memory(pr);
                 break;
         }
         return notifier_from_errno(err);
@@ -235,7 +261,7 @@ static struct notifier_block pseries_mem_nb = {
 static int __init pseries_memory_hotplug_init(void)
 {
         if (firmware_has_feature(FW_FEATURE_LPAR))
-                pSeries_reconfig_notifier_register(&pseries_mem_nb);
+                of_reconfig_notifier_register(&pseries_mem_nb);
 
         return 0;
 }