diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
index 87d83c56b31ec1671007195ce092523535108bb9..09455e1c27c5e4b39b00b415775142f1ebe69614 100644
--- a/arch/powerpc/kernel/prom.c
+++ b/arch/powerpc/kernel/prom.c
@@ -888,9 +888,10 @@ static u64 __init dt_mem_next_cell(int s, cell_t **cellp)
*/
static int __init early_init_dt_scan_drconf_memory(unsigned long node)
{
- cell_t *dm, *ls;
+ cell_t *dm, *ls, *usm;
unsigned long l, n, flags;
u64 base, size, lmb_size;
+ unsigned int is_kexec_kdump = 0, rngs;
ls = (cell_t *)of_get_flat_dt_prop(node, "ibm,lmb-size", &l);
if (ls == NULL || l < dt_root_size_cells * sizeof(cell_t))
@@ -905,6 +906,12 @@ static int __init early_init_dt_scan_drconf_memory(unsigned long node)
if (l < (n * (dt_root_addr_cells + 4) + 1) * sizeof(cell_t))
return 0;
+ /* check if this is a kexec/kdump kernel. */
+ usm = (cell_t *)of_get_flat_dt_prop(node, "linux,drconf-usable-memory",
+ &l);
+ if (usm != NULL)
+ is_kexec_kdump = 1;
+
for (; n != 0; --n) {
base = dt_mem_next_cell(dt_root_addr_cells, &dm);
flags = dm[3];
@@ -915,13 +922,34 @@ static int __init early_init_dt_scan_drconf_memory(unsigned long node)
if ((flags & 0x80) || !(flags & 0x8))
continue;
size = lmb_size;
- if (iommu_is_off) {
- if (base >= 0x80000000ul)
+ rngs = 1;
+ if (is_kexec_kdump) {
+ /*
+ * For each lmb in ibm,dynamic-memory, a corresponding
+ * entry in linux,drconf-usable-memory property contains
+ * a counter 'p' followed by 'p' (base, size) duple.
+ * Now read the counter from
+ * linux,drconf-usable-memory property
+ */
+ rngs = dt_mem_next_cell(dt_root_size_cells, &usm);
+ if (!rngs) /* there are no (base, size) duple */
continue;
- if ((base + size) > 0x80000000ul)
- size = 0x80000000ul - base;
}
- lmb_add(base, size);
+ do {
+ if (is_kexec_kdump) {
+ base = dt_mem_next_cell(dt_root_addr_cells,
+ &usm);
+ size = dt_mem_next_cell(dt_root_size_cells,
+ &usm);
+ }
+ if (iommu_is_off) {
+ if (base >= 0x80000000ul)
+ continue;
+ if ((base + size) > 0x80000000ul)
+ size = 0x80000000ul - base;
+ }
+ lmb_add(base, size);
+ } while (--rngs);
}
lmb_dump_all();
return 0;
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index d9a1813513322889af782dd71625f46db3bab1c4..be05457631d4edd6834073955df15b541ba26e90 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -150,6 +150,21 @@ static const int *of_get_associativity(struct device_node *dev)
return of_get_property(dev, "ibm,associativity", NULL);
}
+/*
+ * Returns the property linux,drconf-usable-memory if
+ * it exists (the property exists only in kexec/kdump kernels,
+ * added by kexec-tools)
+ */
+static const u32 *of_get_usable_memory(struct device_node *memory)
+{
+ const u32 *prop;
+ u32 len;
+ prop = of_get_property(memory, "linux,drconf-usable-memory", &len);
+ if (!prop || len < sizeof(unsigned int))
+ return 0;
+ return prop;
+}
+
/* Returns nid in the range [0..MAX_NUMNODES-1], or -1 if no useful numa
* info is found.
*/
@@ -486,15 +501,30 @@ static unsigned long __init numa_enforce_memory_limit(unsigned long start,
return lmb_end_of_DRAM() - start;
}
+/*
+ * Reads the counter for a given entry in
+ * linux,drconf-usable-memory property
+ */
+static inline int __init read_usm_ranges(const u32 **usm)
+{
+ /*
+ * For each lmb in ibm,dynamic-memory a corresponding
+ * entry in linux,drconf-usable-memory property contains
+ * a counter followed by that many (base, size) duple.
+ * read the counter from linux,drconf-usable-memory
+ */
+ return read_n_cells(n_mem_size_cells, usm);
+}
+
/*
* Extract NUMA information from the ibm,dynamic-reconfiguration-memory
* node. This assumes n_mem_{addr,size}_cells have been set.
*/
static void __init parse_drconf_memory(struct device_node *memory)
{
- const u32 *dm;
- unsigned int n, rc;
- unsigned long lmb_size, size;
+ const u32 *dm, *usm;
+ unsigned int n, rc, ranges, is_kexec_kdump = 0;
+ unsigned long lmb_size, base, size, sz;
int nid;
struct assoc_arrays aa;
@@ -510,6 +540,11 @@ static void __init parse_drconf_memory(struct device_node *memory)
if (rc)
return;
+ /* check if this is a kexec/kdump kernel */
+ usm = of_get_usable_memory(memory);
+ if (usm != NULL)
+ is_kexec_kdump = 1;
+
for (; n != 0; --n) {
struct of_drconf_cell drmem;
@@ -521,21 +556,31 @@ static void __init parse_drconf_memory(struct device_node *memory)
|| !(drmem.flags & DRCONF_MEM_ASSIGNED))
continue;
- nid = of_drconf_to_nid_single(&drmem, &aa);
+ base = drmem.base_addr;
+ size = lmb_size;
+ ranges = 1;
- fake_numa_create_new_node(
- ((drmem.base_addr + lmb_size) >> PAGE_SHIFT),
+ if (is_kexec_kdump) {
+ ranges = read_usm_ranges(&usm);
+ if (!ranges) /* there are no (base, size) duple */
+ continue;
+ }
+ do {
+ if (is_kexec_kdump) {
+ base = read_n_cells(n_mem_addr_cells, &usm);
+ size = read_n_cells(n_mem_size_cells, &usm);
+ }
+ nid = of_drconf_to_nid_single(&drmem, &aa);
+ fake_numa_create_new_node(
+ ((base + size) >> PAGE_SHIFT),
&nid);
-
- node_set_online(nid);
-
- size = numa_enforce_memory_limit(drmem.base_addr, lmb_size);
- if (!size)
- continue;
-
- add_active_range(nid, drmem.base_addr >> PAGE_SHIFT,
- (drmem.base_addr >> PAGE_SHIFT)
- + (size >> PAGE_SHIFT));
+ node_set_online(nid);
+ sz = numa_enforce_memory_limit(base, size);
+ if (sz)
+ add_active_range(nid, base >> PAGE_SHIFT,
+ (base >> PAGE_SHIFT)
+ + (sz >> PAGE_SHIFT));
+ } while (--ranges);
}
}