1 files changed, 268 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/pseries/hotplug-memory.c b/arch/powerpc/platforms/pseries/hotplug-memory.c
new file mode 100644
index 00000000000..7995135170a
--- /dev/null
+++ b/arch/powerpc/platforms/pseries/hotplug-memory.c
@@ -0,0 +1,268 @@
+/*
+ * pseries Memory Hotplug infrastructure.
+ *
+ * Copyright (C) 2008 Badari Pulavarty, IBM Corporation
+ *
+ *      This program is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU General Public License
+ *      as published by the Free Software Foundation; either version
+ *      2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/memblock.h>
+#include <linux/vmalloc.h>
+#include <linux/memory.h>
+#include <linux/memory_hotplug.h>
+
+#include <asm/firmware.h>
+#include <asm/machdep.h>
+#include <asm/prom.h>
+#include <asm/sparsemem.h>
+
+unsigned long pseries_memory_block_size(void)
+{
+	struct device_node *np;
+	unsigned int memblock_size = MIN_MEMORY_BLOCK_SIZE;
+	struct resource r;
+
+	np = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
+	if (np) {
+		const __be64 *size;
+
+		size = of_get_property(np, "ibm,lmb-size", NULL);
+		if (size)
+			memblock_size = be64_to_cpup(size);
+		of_node_put(np);
+	} else  if (machine_is(pseries)) {
+		/* This fallback really only applies to pseries */
+		unsigned int memzero_size = 0;
+
+		np = of_find_node_by_path("/memory@0");
+		if (np) {
+			if (!of_address_to_resource(np, 0, &r))
+				memzero_size = resource_size(&r);
+			of_node_put(np);
+		}
+
+		if (memzero_size) {
+			/* We now know the size of memory@0, use this to find
+			 * the first memoryblock and get its size.
+			 */
+			char buf[64];
+
+			sprintf(buf, "/memory@%x", memzero_size);
+			np = of_find_node_by_path(buf);
+			if (np) {
+				if (!of_address_to_resource(np, 0, &r))
+					memblock_size = resource_size(&r);
+				of_node_put(np);
+			}
+		}
+	}
+	return memblock_size;
+}
+
+#ifdef CONFIG_MEMORY_HOTREMOVE
+static int pseries_remove_memory(u64 start, u64 size)
+{
+	int ret;
+
+	/* Remove htab bolted mappings for this section of memory */
+	start = (unsigned long)__va(start);
+	ret = remove_section_mapping(start, start + size);
+
+	/* Ensure all vmalloc mappings are flushed in case they also
+	 * hit that section of memory
+	 */
+	vm_unmap_aliases();
+
+	return ret;
+}
+
+static int pseries_remove_memblock(unsigned long base, unsigned int memblock_size)
+{
+	unsigned long block_sz, start_pfn;
+	int sections_per_block;
+	int i, nid;
+
+	start_pfn = base >> PAGE_SHIFT;
+
+	lock_device_hotplug();
+
+	if (!pfn_valid(start_pfn))
+		goto out;
+
+	block_sz = pseries_memory_block_size();
+	sections_per_block = block_sz / MIN_MEMORY_BLOCK_SIZE;
+	nid = memory_add_physaddr_to_nid(base);
+
+	for (i = 0; i < sections_per_block; i++) {
+		remove_memory(nid, base, MIN_MEMORY_BLOCK_SIZE);
+		base += MIN_MEMORY_BLOCK_SIZE;
+	}
+
+out:
+	/* Update memory regions for memory remove */
+	memblock_remove(base, memblock_size);
+	unlock_device_hotplug();
+	return 0;
+}
+
+static int pseries_remove_mem_node(struct device_node *np)
+{
+	const char *type;
+	const unsigned int *regs;
+	unsigned long base;
+	unsigned int lmb_size;
+	int ret = -EINVAL;
+
+	/*
+	 * Check to see if we are actually removing memory
+	 */
+	type = of_get_property(np, "device_type", NULL);
+	if (type == NULL || strcmp(type, "memory") != 0)
+		return 0;
+
+	/*
+	 * Find the bae address and size of the memblock
+	 */
+	regs = of_get_property(np, "reg", NULL);
+	if (!regs)
+		return ret;
+
+	base = *(unsigned long *)regs;
+	lmb_size = regs[3];
+
+	pseries_remove_memblock(base, lmb_size);
+	return 0;
+}
+#else
+static inline int pseries_remove_memblock(unsigned long base,
+					  unsigned int memblock_size)
+{
+	return -EOPNOTSUPP;
+}
+static inline int pseries_remove_mem_node(struct device_node *np)
+{
+	return -EOPNOTSUPP;
+}
+#endif /* CONFIG_MEMORY_HOTREMOVE */
+
+static int pseries_add_mem_node(struct device_node *np)
+{
+	const char *type;
+	const unsigned int *regs;
+	unsigned long base;
+	unsigned int lmb_size;
+	int ret = -EINVAL;
+
+	/*
+	 * Check to see if we are actually adding memory
+	 */
+	type = of_get_property(np, "device_type", NULL);
+	if (type == NULL || strcmp(type, "memory") != 0)
+		return 0;
+
+	/*
+	 * Find the base and size of the memblock
+	 */
+	regs = of_get_property(np, "reg", NULL);
+	if (!regs)
+		return ret;
+
+	base = *(unsigned long *)regs;
+	lmb_size = regs[3];
+
+	/*
+	 * Update memory region to represent the memory add
+	 */
+	ret = memblock_add(base, lmb_size);
+	return (ret < 0) ? -EINVAL : 0;
+}
+
+static int pseries_update_drconf_memory(struct of_prop_reconfig *pr)
+{
+	struct of_drconf_cell *new_drmem, *old_drmem;
+	unsigned long memblock_size;
+	u32 entries;
+	u32 *p;
+	int i, rc = -EINVAL;
+
+	memblock_size = pseries_memory_block_size();
+	if (!memblock_size)
+		return -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)
+{
+	struct of_prop_reconfig *pr;
+	int err = 0;
+
+	switch (action) {
+	case OF_RECONFIG_ATTACH_NODE:
+		err = pseries_add_mem_node(node);
+		break;
+	case OF_RECONFIG_DETACH_NODE:
+		err = pseries_remove_mem_node(node);
+		break;
+	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);
+}
+
+static struct notifier_block pseries_mem_nb = {
+	.notifier_call = pseries_memory_notifier,
+};
+
+static int __init pseries_memory_hotplug_init(void)
+{
+	if (firmware_has_feature(FW_FEATURE_LPAR))
+		of_reconfig_notifier_register(&pseries_mem_nb);
+
+#ifdef CONFIG_MEMORY_HOTREMOVE
+	ppc_md.remove_memory = pseries_remove_memory;
+#endif
+
+	return 0;
+}
+machine_device_initcall(pseries, pseries_memory_hotplug_init);