2 * Dynamic reconfiguration memory support
4 * Copyright 2017 IBM Corporation
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
12 #define pr_fmt(fmt) "drmem: " fmt
14 #include <linux/kernel.h>
16 #include <linux/of_fdt.h>
17 #include <linux/memblock.h>
19 #include <asm/drmem.h>
21 static struct drmem_lmb_info __drmem_info;
22 struct drmem_lmb_info *drmem_info = &__drmem_info;
24 u64 drmem_lmb_memory_max(void)
26 struct drmem_lmb *last_lmb;
28 last_lmb = &drmem_info->lmbs[drmem_info->n_lmbs - 1];
29 return last_lmb->base_addr + drmem_lmb_size();
32 static u32 drmem_lmb_flags(struct drmem_lmb *lmb)
35 * Return the value of the lmb flags field minus the reserved
36 * bit used internally for hotplug processing.
38 return lmb->flags & ~DRMEM_LMB_RESERVED;
41 static struct property *clone_property(struct property *prop, u32 prop_sz)
43 struct property *new_prop;
45 new_prop = kzalloc(sizeof(*new_prop), GFP_KERNEL);
49 new_prop->name = kstrdup(prop->name, GFP_KERNEL);
50 new_prop->value = kzalloc(prop_sz, GFP_KERNEL);
51 if (!new_prop->name || !new_prop->value) {
52 kfree(new_prop->name);
53 kfree(new_prop->value);
58 new_prop->length = prop_sz;
59 #if defined(CONFIG_OF_DYNAMIC)
60 of_property_set_flag(new_prop, OF_DYNAMIC);
65 static int drmem_update_dt_v1(struct device_node *memory,
66 struct property *prop)
68 struct property *new_prop;
69 struct of_drconf_cell_v1 *dr_cell;
70 struct drmem_lmb *lmb;
73 new_prop = clone_property(prop, prop->length);
78 *p++ = cpu_to_be32(drmem_info->n_lmbs);
80 dr_cell = (struct of_drconf_cell_v1 *)p;
82 for_each_drmem_lmb(lmb) {
83 dr_cell->base_addr = cpu_to_be64(lmb->base_addr);
84 dr_cell->drc_index = cpu_to_be32(lmb->drc_index);
85 dr_cell->aa_index = cpu_to_be32(lmb->aa_index);
86 dr_cell->flags = cpu_to_be32(drmem_lmb_flags(lmb));
91 of_update_property(memory, new_prop);
95 static void init_drconf_v2_cell(struct of_drconf_cell_v2 *dr_cell,
96 struct drmem_lmb *lmb)
98 dr_cell->base_addr = cpu_to_be64(lmb->base_addr);
99 dr_cell->drc_index = cpu_to_be32(lmb->drc_index);
100 dr_cell->aa_index = cpu_to_be32(lmb->aa_index);
101 dr_cell->flags = cpu_to_be32(drmem_lmb_flags(lmb));
104 static int drmem_update_dt_v2(struct device_node *memory,
105 struct property *prop)
107 struct property *new_prop;
108 struct of_drconf_cell_v2 *dr_cell;
109 struct drmem_lmb *lmb, *prev_lmb;
110 u32 lmb_sets, prop_sz, seq_lmbs;
113 /* First pass, determine how many LMB sets are needed. */
116 for_each_drmem_lmb(lmb) {
123 if (prev_lmb->aa_index != lmb->aa_index ||
124 drmem_lmb_flags(prev_lmb) != drmem_lmb_flags(lmb))
130 prop_sz = lmb_sets * sizeof(*dr_cell) + sizeof(__be32);
131 new_prop = clone_property(prop, prop_sz);
136 *p++ = cpu_to_be32(lmb_sets);
138 dr_cell = (struct of_drconf_cell_v2 *)p;
140 /* Second pass, populate the LMB set data */
143 for_each_drmem_lmb(lmb) {
144 if (prev_lmb == NULL) {
145 /* Start of first LMB set */
147 init_drconf_v2_cell(dr_cell, lmb);
152 if (prev_lmb->aa_index != lmb->aa_index ||
153 drmem_lmb_flags(prev_lmb) != drmem_lmb_flags(lmb)) {
154 /* end of one set, start of another */
155 dr_cell->seq_lmbs = cpu_to_be32(seq_lmbs);
158 init_drconf_v2_cell(dr_cell, lmb);
167 /* close out last LMB set */
168 dr_cell->seq_lmbs = cpu_to_be32(seq_lmbs);
169 of_update_property(memory, new_prop);
173 int drmem_update_dt(void)
175 struct device_node *memory;
176 struct property *prop;
179 memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
183 prop = of_find_property(memory, "ibm,dynamic-memory", NULL);
185 rc = drmem_update_dt_v1(memory, prop);
187 prop = of_find_property(memory, "ibm,dynamic-memory-v2", NULL);
189 rc = drmem_update_dt_v2(memory, prop);
196 static void __init read_drconf_v1_cell(struct drmem_lmb *lmb,
199 const __be32 *p = *prop;
201 lmb->base_addr = dt_mem_next_cell(dt_root_addr_cells, &p);
202 lmb->drc_index = of_read_number(p++, 1);
204 p++; /* skip reserved field */
206 lmb->aa_index = of_read_number(p++, 1);
207 lmb->flags = of_read_number(p++, 1);
212 static void __init __walk_drmem_v1_lmbs(const __be32 *prop, const __be32 *usm,
213 void (*func)(struct drmem_lmb *, const __be32 **))
215 struct drmem_lmb lmb;
218 n_lmbs = of_read_number(prop++, 1);
222 for (i = 0; i < n_lmbs; i++) {
223 read_drconf_v1_cell(&lmb, &prop);
228 static void __init read_drconf_v2_cell(struct of_drconf_cell_v2 *dr_cell,
231 const __be32 *p = *prop;
233 dr_cell->seq_lmbs = of_read_number(p++, 1);
234 dr_cell->base_addr = dt_mem_next_cell(dt_root_addr_cells, &p);
235 dr_cell->drc_index = of_read_number(p++, 1);
236 dr_cell->aa_index = of_read_number(p++, 1);
237 dr_cell->flags = of_read_number(p++, 1);
242 static void __init __walk_drmem_v2_lmbs(const __be32 *prop, const __be32 *usm,
243 void (*func)(struct drmem_lmb *, const __be32 **))
245 struct of_drconf_cell_v2 dr_cell;
246 struct drmem_lmb lmb;
249 lmb_sets = of_read_number(prop++, 1);
253 for (i = 0; i < lmb_sets; i++) {
254 read_drconf_v2_cell(&dr_cell, &prop);
256 for (j = 0; j < dr_cell.seq_lmbs; j++) {
257 lmb.base_addr = dr_cell.base_addr;
258 dr_cell.base_addr += drmem_lmb_size();
260 lmb.drc_index = dr_cell.drc_index;
263 lmb.aa_index = dr_cell.aa_index;
264 lmb.flags = dr_cell.flags;
271 #ifdef CONFIG_PPC_PSERIES
272 void __init walk_drmem_lmbs_early(unsigned long node,
273 void (*func)(struct drmem_lmb *, const __be32 **))
275 const __be32 *prop, *usm;
278 prop = of_get_flat_dt_prop(node, "ibm,lmb-size", &len);
279 if (!prop || len < dt_root_size_cells * sizeof(__be32))
282 drmem_info->lmb_size = dt_mem_next_cell(dt_root_size_cells, &prop);
284 usm = of_get_flat_dt_prop(node, "linux,drconf-usable-memory", &len);
286 prop = of_get_flat_dt_prop(node, "ibm,dynamic-memory", &len);
288 __walk_drmem_v1_lmbs(prop, usm, func);
290 prop = of_get_flat_dt_prop(node, "ibm,dynamic-memory-v2",
293 __walk_drmem_v2_lmbs(prop, usm, func);
301 static int __init init_drmem_lmb_size(struct device_node *dn)
306 if (drmem_info->lmb_size)
309 prop = of_get_property(dn, "ibm,lmb-size", &len);
310 if (!prop || len < dt_root_size_cells * sizeof(__be32)) {
311 pr_info("Could not determine LMB size\n");
315 drmem_info->lmb_size = dt_mem_next_cell(dt_root_size_cells, &prop);
320 * Returns the property linux,drconf-usable-memory if
321 * it exists (the property exists only in kexec/kdump kernels,
322 * added by kexec-tools)
324 static const __be32 *of_get_usable_memory(struct device_node *dn)
329 prop = of_get_property(dn, "linux,drconf-usable-memory", &len);
330 if (!prop || len < sizeof(unsigned int))
336 void __init walk_drmem_lmbs(struct device_node *dn,
337 void (*func)(struct drmem_lmb *, const __be32 **))
339 const __be32 *prop, *usm;
341 if (init_drmem_lmb_size(dn))
344 usm = of_get_usable_memory(dn);
346 prop = of_get_property(dn, "ibm,dynamic-memory", NULL);
348 __walk_drmem_v1_lmbs(prop, usm, func);
350 prop = of_get_property(dn, "ibm,dynamic-memory-v2", NULL);
352 __walk_drmem_v2_lmbs(prop, usm, func);
356 static void __init init_drmem_v1_lmbs(const __be32 *prop)
358 struct drmem_lmb *lmb;
360 drmem_info->n_lmbs = of_read_number(prop++, 1);
361 if (drmem_info->n_lmbs == 0)
364 drmem_info->lmbs = kcalloc(drmem_info->n_lmbs, sizeof(*lmb),
366 if (!drmem_info->lmbs)
369 for_each_drmem_lmb(lmb)
370 read_drconf_v1_cell(lmb, &prop);
373 static void __init init_drmem_v2_lmbs(const __be32 *prop)
375 struct drmem_lmb *lmb;
376 struct of_drconf_cell_v2 dr_cell;
381 lmb_sets = of_read_number(prop++, 1);
385 /* first pass, calculate the number of LMBs */
387 for (i = 0; i < lmb_sets; i++) {
388 read_drconf_v2_cell(&dr_cell, &p);
389 drmem_info->n_lmbs += dr_cell.seq_lmbs;
392 drmem_info->lmbs = kcalloc(drmem_info->n_lmbs, sizeof(*lmb),
394 if (!drmem_info->lmbs)
397 /* second pass, read in the LMB information */
401 for (i = 0; i < lmb_sets; i++) {
402 read_drconf_v2_cell(&dr_cell, &p);
404 for (j = 0; j < dr_cell.seq_lmbs; j++) {
405 lmb = &drmem_info->lmbs[lmb_index++];
407 lmb->base_addr = dr_cell.base_addr;
408 dr_cell.base_addr += drmem_info->lmb_size;
410 lmb->drc_index = dr_cell.drc_index;
413 lmb->aa_index = dr_cell.aa_index;
414 lmb->flags = dr_cell.flags;
419 static int __init drmem_init(void)
421 struct device_node *dn;
424 dn = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
426 pr_info("No dynamic reconfiguration memory found\n");
430 if (init_drmem_lmb_size(dn)) {
435 prop = of_get_property(dn, "ibm,dynamic-memory", NULL);
437 init_drmem_v1_lmbs(prop);
439 prop = of_get_property(dn, "ibm,dynamic-memory-v2", NULL);
441 init_drmem_v2_lmbs(prop);
447 late_initcall(drmem_init);