v4.19.13 snapshot.
diff --git a/arch/powerpc/mm/drmem.c b/arch/powerpc/mm/drmem.c
new file mode 100644
index 0000000..3f18036
--- /dev/null
+++ b/arch/powerpc/mm/drmem.c
@@ -0,0 +1,447 @@
+/*
+ * Dynamic reconfiguration memory support
+ *
+ * Copyright 2017 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.
+ */
+
+#define pr_fmt(fmt) "drmem: " fmt
+
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/memblock.h>
+#include <asm/prom.h>
+#include <asm/drmem.h>
+
+static struct drmem_lmb_info __drmem_info;
+struct drmem_lmb_info *drmem_info = &__drmem_info;
+
+u64 drmem_lmb_memory_max(void)
+{
+ struct drmem_lmb *last_lmb;
+
+ last_lmb = &drmem_info->lmbs[drmem_info->n_lmbs - 1];
+ return last_lmb->base_addr + drmem_lmb_size();
+}
+
+static u32 drmem_lmb_flags(struct drmem_lmb *lmb)
+{
+ /*
+ * Return the value of the lmb flags field minus the reserved
+ * bit used internally for hotplug processing.
+ */
+ return lmb->flags & ~DRMEM_LMB_RESERVED;
+}
+
+static struct property *clone_property(struct property *prop, u32 prop_sz)
+{
+ struct property *new_prop;
+
+ new_prop = kzalloc(sizeof(*new_prop), GFP_KERNEL);
+ if (!new_prop)
+ return NULL;
+
+ new_prop->name = kstrdup(prop->name, GFP_KERNEL);
+ new_prop->value = kzalloc(prop_sz, GFP_KERNEL);
+ if (!new_prop->name || !new_prop->value) {
+ kfree(new_prop->name);
+ kfree(new_prop->value);
+ kfree(new_prop);
+ return NULL;
+ }
+
+ new_prop->length = prop_sz;
+#if defined(CONFIG_OF_DYNAMIC)
+ of_property_set_flag(new_prop, OF_DYNAMIC);
+#endif
+ return new_prop;
+}
+
+static int drmem_update_dt_v1(struct device_node *memory,
+ struct property *prop)
+{
+ struct property *new_prop;
+ struct of_drconf_cell_v1 *dr_cell;
+ struct drmem_lmb *lmb;
+ u32 *p;
+
+ new_prop = clone_property(prop, prop->length);
+ if (!new_prop)
+ return -1;
+
+ p = new_prop->value;
+ *p++ = cpu_to_be32(drmem_info->n_lmbs);
+
+ dr_cell = (struct of_drconf_cell_v1 *)p;
+
+ for_each_drmem_lmb(lmb) {
+ dr_cell->base_addr = cpu_to_be64(lmb->base_addr);
+ dr_cell->drc_index = cpu_to_be32(lmb->drc_index);
+ dr_cell->aa_index = cpu_to_be32(lmb->aa_index);
+ dr_cell->flags = cpu_to_be32(drmem_lmb_flags(lmb));
+
+ dr_cell++;
+ }
+
+ of_update_property(memory, new_prop);
+ return 0;
+}
+
+static void init_drconf_v2_cell(struct of_drconf_cell_v2 *dr_cell,
+ struct drmem_lmb *lmb)
+{
+ dr_cell->base_addr = cpu_to_be64(lmb->base_addr);
+ dr_cell->drc_index = cpu_to_be32(lmb->drc_index);
+ dr_cell->aa_index = cpu_to_be32(lmb->aa_index);
+ dr_cell->flags = cpu_to_be32(drmem_lmb_flags(lmb));
+}
+
+static int drmem_update_dt_v2(struct device_node *memory,
+ struct property *prop)
+{
+ struct property *new_prop;
+ struct of_drconf_cell_v2 *dr_cell;
+ struct drmem_lmb *lmb, *prev_lmb;
+ u32 lmb_sets, prop_sz, seq_lmbs;
+ u32 *p;
+
+ /* First pass, determine how many LMB sets are needed. */
+ lmb_sets = 0;
+ prev_lmb = NULL;
+ for_each_drmem_lmb(lmb) {
+ if (!prev_lmb) {
+ prev_lmb = lmb;
+ lmb_sets++;
+ continue;
+ }
+
+ if (prev_lmb->aa_index != lmb->aa_index ||
+ drmem_lmb_flags(prev_lmb) != drmem_lmb_flags(lmb))
+ lmb_sets++;
+
+ prev_lmb = lmb;
+ }
+
+ prop_sz = lmb_sets * sizeof(*dr_cell) + sizeof(__be32);
+ new_prop = clone_property(prop, prop_sz);
+ if (!new_prop)
+ return -1;
+
+ p = new_prop->value;
+ *p++ = cpu_to_be32(lmb_sets);
+
+ dr_cell = (struct of_drconf_cell_v2 *)p;
+
+ /* Second pass, populate the LMB set data */
+ prev_lmb = NULL;
+ seq_lmbs = 0;
+ for_each_drmem_lmb(lmb) {
+ if (prev_lmb == NULL) {
+ /* Start of first LMB set */
+ prev_lmb = lmb;
+ init_drconf_v2_cell(dr_cell, lmb);
+ seq_lmbs++;
+ continue;
+ }
+
+ if (prev_lmb->aa_index != lmb->aa_index ||
+ drmem_lmb_flags(prev_lmb) != drmem_lmb_flags(lmb)) {
+ /* end of one set, start of another */
+ dr_cell->seq_lmbs = cpu_to_be32(seq_lmbs);
+ dr_cell++;
+
+ init_drconf_v2_cell(dr_cell, lmb);
+ seq_lmbs = 1;
+ } else {
+ seq_lmbs++;
+ }
+
+ prev_lmb = lmb;
+ }
+
+ /* close out last LMB set */
+ dr_cell->seq_lmbs = cpu_to_be32(seq_lmbs);
+ of_update_property(memory, new_prop);
+ return 0;
+}
+
+int drmem_update_dt(void)
+{
+ struct device_node *memory;
+ struct property *prop;
+ int rc = -1;
+
+ memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
+ if (!memory)
+ return -1;
+
+ prop = of_find_property(memory, "ibm,dynamic-memory", NULL);
+ if (prop) {
+ rc = drmem_update_dt_v1(memory, prop);
+ } else {
+ prop = of_find_property(memory, "ibm,dynamic-memory-v2", NULL);
+ if (prop)
+ rc = drmem_update_dt_v2(memory, prop);
+ }
+
+ of_node_put(memory);
+ return rc;
+}
+
+static void __init read_drconf_v1_cell(struct drmem_lmb *lmb,
+ const __be32 **prop)
+{
+ const __be32 *p = *prop;
+
+ lmb->base_addr = dt_mem_next_cell(dt_root_addr_cells, &p);
+ lmb->drc_index = of_read_number(p++, 1);
+
+ p++; /* skip reserved field */
+
+ lmb->aa_index = of_read_number(p++, 1);
+ lmb->flags = of_read_number(p++, 1);
+
+ *prop = p;
+}
+
+static void __init __walk_drmem_v1_lmbs(const __be32 *prop, const __be32 *usm,
+ void (*func)(struct drmem_lmb *, const __be32 **))
+{
+ struct drmem_lmb lmb;
+ u32 i, n_lmbs;
+
+ n_lmbs = of_read_number(prop++, 1);
+ if (n_lmbs == 0)
+ return;
+
+ for (i = 0; i < n_lmbs; i++) {
+ read_drconf_v1_cell(&lmb, &prop);
+ func(&lmb, &usm);
+ }
+}
+
+static void __init read_drconf_v2_cell(struct of_drconf_cell_v2 *dr_cell,
+ const __be32 **prop)
+{
+ const __be32 *p = *prop;
+
+ dr_cell->seq_lmbs = of_read_number(p++, 1);
+ dr_cell->base_addr = dt_mem_next_cell(dt_root_addr_cells, &p);
+ dr_cell->drc_index = of_read_number(p++, 1);
+ dr_cell->aa_index = of_read_number(p++, 1);
+ dr_cell->flags = of_read_number(p++, 1);
+
+ *prop = p;
+}
+
+static void __init __walk_drmem_v2_lmbs(const __be32 *prop, const __be32 *usm,
+ void (*func)(struct drmem_lmb *, const __be32 **))
+{
+ struct of_drconf_cell_v2 dr_cell;
+ struct drmem_lmb lmb;
+ u32 i, j, lmb_sets;
+
+ lmb_sets = of_read_number(prop++, 1);
+ if (lmb_sets == 0)
+ return;
+
+ for (i = 0; i < lmb_sets; i++) {
+ read_drconf_v2_cell(&dr_cell, &prop);
+
+ for (j = 0; j < dr_cell.seq_lmbs; j++) {
+ lmb.base_addr = dr_cell.base_addr;
+ dr_cell.base_addr += drmem_lmb_size();
+
+ lmb.drc_index = dr_cell.drc_index;
+ dr_cell.drc_index++;
+
+ lmb.aa_index = dr_cell.aa_index;
+ lmb.flags = dr_cell.flags;
+
+ func(&lmb, &usm);
+ }
+ }
+}
+
+#ifdef CONFIG_PPC_PSERIES
+void __init walk_drmem_lmbs_early(unsigned long node,
+ void (*func)(struct drmem_lmb *, const __be32 **))
+{
+ const __be32 *prop, *usm;
+ int len;
+
+ prop = of_get_flat_dt_prop(node, "ibm,lmb-size", &len);
+ if (!prop || len < dt_root_size_cells * sizeof(__be32))
+ return;
+
+ drmem_info->lmb_size = dt_mem_next_cell(dt_root_size_cells, &prop);
+
+ usm = of_get_flat_dt_prop(node, "linux,drconf-usable-memory", &len);
+
+ prop = of_get_flat_dt_prop(node, "ibm,dynamic-memory", &len);
+ if (prop) {
+ __walk_drmem_v1_lmbs(prop, usm, func);
+ } else {
+ prop = of_get_flat_dt_prop(node, "ibm,dynamic-memory-v2",
+ &len);
+ if (prop)
+ __walk_drmem_v2_lmbs(prop, usm, func);
+ }
+
+ memblock_dump_all();
+}
+
+#endif
+
+static int __init init_drmem_lmb_size(struct device_node *dn)
+{
+ const __be32 *prop;
+ int len;
+
+ if (drmem_info->lmb_size)
+ return 0;
+
+ prop = of_get_property(dn, "ibm,lmb-size", &len);
+ if (!prop || len < dt_root_size_cells * sizeof(__be32)) {
+ pr_info("Could not determine LMB size\n");
+ return -1;
+ }
+
+ drmem_info->lmb_size = dt_mem_next_cell(dt_root_size_cells, &prop);
+ return 0;
+}
+
+/*
+ * Returns the property linux,drconf-usable-memory if
+ * it exists (the property exists only in kexec/kdump kernels,
+ * added by kexec-tools)
+ */
+static const __be32 *of_get_usable_memory(struct device_node *dn)
+{
+ const __be32 *prop;
+ u32 len;
+
+ prop = of_get_property(dn, "linux,drconf-usable-memory", &len);
+ if (!prop || len < sizeof(unsigned int))
+ return NULL;
+
+ return prop;
+}
+
+void __init walk_drmem_lmbs(struct device_node *dn,
+ void (*func)(struct drmem_lmb *, const __be32 **))
+{
+ const __be32 *prop, *usm;
+
+ if (init_drmem_lmb_size(dn))
+ return;
+
+ usm = of_get_usable_memory(dn);
+
+ prop = of_get_property(dn, "ibm,dynamic-memory", NULL);
+ if (prop) {
+ __walk_drmem_v1_lmbs(prop, usm, func);
+ } else {
+ prop = of_get_property(dn, "ibm,dynamic-memory-v2", NULL);
+ if (prop)
+ __walk_drmem_v2_lmbs(prop, usm, func);
+ }
+}
+
+static void __init init_drmem_v1_lmbs(const __be32 *prop)
+{
+ struct drmem_lmb *lmb;
+
+ drmem_info->n_lmbs = of_read_number(prop++, 1);
+ if (drmem_info->n_lmbs == 0)
+ return;
+
+ drmem_info->lmbs = kcalloc(drmem_info->n_lmbs, sizeof(*lmb),
+ GFP_KERNEL);
+ if (!drmem_info->lmbs)
+ return;
+
+ for_each_drmem_lmb(lmb)
+ read_drconf_v1_cell(lmb, &prop);
+}
+
+static void __init init_drmem_v2_lmbs(const __be32 *prop)
+{
+ struct drmem_lmb *lmb;
+ struct of_drconf_cell_v2 dr_cell;
+ const __be32 *p;
+ u32 i, j, lmb_sets;
+ int lmb_index;
+
+ lmb_sets = of_read_number(prop++, 1);
+ if (lmb_sets == 0)
+ return;
+
+ /* first pass, calculate the number of LMBs */
+ p = prop;
+ for (i = 0; i < lmb_sets; i++) {
+ read_drconf_v2_cell(&dr_cell, &p);
+ drmem_info->n_lmbs += dr_cell.seq_lmbs;
+ }
+
+ drmem_info->lmbs = kcalloc(drmem_info->n_lmbs, sizeof(*lmb),
+ GFP_KERNEL);
+ if (!drmem_info->lmbs)
+ return;
+
+ /* second pass, read in the LMB information */
+ lmb_index = 0;
+ p = prop;
+
+ for (i = 0; i < lmb_sets; i++) {
+ read_drconf_v2_cell(&dr_cell, &p);
+
+ for (j = 0; j < dr_cell.seq_lmbs; j++) {
+ lmb = &drmem_info->lmbs[lmb_index++];
+
+ lmb->base_addr = dr_cell.base_addr;
+ dr_cell.base_addr += drmem_info->lmb_size;
+
+ lmb->drc_index = dr_cell.drc_index;
+ dr_cell.drc_index++;
+
+ lmb->aa_index = dr_cell.aa_index;
+ lmb->flags = dr_cell.flags;
+ }
+ }
+}
+
+static int __init drmem_init(void)
+{
+ struct device_node *dn;
+ const __be32 *prop;
+
+ dn = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
+ if (!dn) {
+ pr_info("No dynamic reconfiguration memory found\n");
+ return 0;
+ }
+
+ if (init_drmem_lmb_size(dn)) {
+ of_node_put(dn);
+ return 0;
+ }
+
+ prop = of_get_property(dn, "ibm,dynamic-memory", NULL);
+ if (prop) {
+ init_drmem_v1_lmbs(prop);
+ } else {
+ prop = of_get_property(dn, "ibm,dynamic-memory-v2", NULL);
+ if (prop)
+ init_drmem_v2_lmbs(prop);
+ }
+
+ of_node_put(dn);
+ return 0;
+}
+late_initcall(drmem_init);