Adding numa dt binding support for arm64 based platforms.
dt node parsing for numa topology is done using device property
numa-node-id and device node distance-map.
Reviewed-by: Robert Richter <rrichter@xxxxxxxxxx>
Signed-off-by: Ganapatrao Kulkarni <gkulkarni@xxxxxxxxxxxxxxxxxx>
---
arch/arm64/Kconfig | 10 ++
arch/arm64/include/asm/numa.h | 10 ++
arch/arm64/kernel/Makefile | 1 +
arch/arm64/kernel/of_numa.c | 257 ++++++++++++++++++++++++++++++++++++++++++
arch/arm64/kernel/smp.c | 2 +
arch/arm64/mm/numa.c | 10 +-
6 files changed, 289 insertions(+), 1 deletion(-)
create mode 100644 arch/arm64/kernel/of_numa.c
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 74f5d73..775cf4a 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -515,6 +515,16 @@ config NUMA
local memory of the CPU and add some more
NUMA awareness to the kernel.
+config OF_NUMA
+ bool "Device Tree NUMA support"
+ depends on NUMA
+ depends on OF
+ default y
+ help
+ Enable Device Tree NUMA support.
+ This enables the numa mapping of cpu, memory, io and
+ inter node distances using dt bindings.
+
config NODES_SHIFT
int "Maximum NUMA Nodes (as a power of 2)"
range 1 10
diff --git a/arch/arm64/include/asm/numa.h b/arch/arm64/include/asm/numa.h
index f28f15b0..54deb38 100644
--- a/arch/arm64/include/asm/numa.h
+++ b/arch/arm64/include/asm/numa.h
@@ -37,4 +37,14 @@ void numa_store_cpu_info(unsigned int cpu);
static inline void numa_store_cpu_info(unsigned int cpu) { }
static inline void arm64_numa_init(void) { }
#endif /* CONFIG_NUMA */
+
+struct device_node;
+#ifdef CONFIG_OF_NUMA
+int __init arm64_of_numa_init(void);
+void __init of_numa_set_node_info(unsigned int cpu, struct device_node *dn);
+#else
+static inline void of_numa_set_node_info(unsigned int cpu,
+ struct device_node *dn) { }
+#endif
+
#endif /* __ASM_NUMA_H */
diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile
index 474691f..7987763 100644
--- a/arch/arm64/kernel/Makefile
+++ b/arch/arm64/kernel/Makefile
@@ -41,6 +41,7 @@ arm64-obj-$(CONFIG_EFI) += efi.o efi-entry.stub.o
arm64-obj-$(CONFIG_PCI) += pci.o
arm64-obj-$(CONFIG_ARMV8_DEPRECATED) += armv8_deprecated.o
arm64-obj-$(CONFIG_ACPI) += acpi.o
+arm64-obj-$(CONFIG_OF_NUMA) += of_numa.o
obj-y += $(arm64-obj-y) vdso/
obj-m += $(arm64-obj-m)
diff --git a/arch/arm64/kernel/of_numa.c b/arch/arm64/kernel/of_numa.c
new file mode 100644
index 0000000..2f9e34b
--- /dev/null
+++ b/arch/arm64/kernel/of_numa.c
@@ -0,0 +1,257 @@
+/*
+ * OF NUMA Parsing support.
+ *
+ * Copyright (C) 2015 Cavium Inc.
+ * Author: Ganapatrao Kulkarni <gkulkarni@xxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/ctype.h>
+#include <linux/memblock.h>
+#include <linux/module.h>
+#include <linux/nodemask.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+
+#include <asm/smp_plat.h>
+
+/* define default numa node to 0 */
+#define DEFAULT_NODE 0
+#define OF_NUMA_PROP "numa-node-id"
+
+/* Returns nid in the range [0..MAX_NUMNODES-1],
+ * or NUMA_NO_NODE if no valid numa-node-id entry found
+ * or DEFAULT_NODE if no numa-node-id entry exists
+ */
+static int of_numa_prop_to_nid(const __be32 *of_numa_prop, int length)
+{
+ int nid;
+
+ if (!of_numa_prop)
+ return DEFAULT_NODE;
+
+ if (length != sizeof(*of_numa_prop)) {
+ pr_warn("NUMA: Invalid of_numa_prop length %d found.\n",
+ length);
+ return NUMA_NO_NODE;
+ }
+
+ nid = of_read_number(of_numa_prop, 1);
+ if (nid >= MAX_NUMNODES) {
+ pr_warn("NUMA: Invalid numa node %d found.\n", nid);
+ return NUMA_NO_NODE;
+ }
+
+ return nid;
+}
+
+/* Must hold reference to node during call */
+static int of_get_numa_nid(struct device_node *device)
+{
+ int length;
+ const __be32 *of_numa_prop;
+
+ of_numa_prop = of_get_property(device, OF_NUMA_PROP, &length);
+
+ return of_numa_prop_to_nid(of_numa_prop, length);
+}
+
+static int __init early_init_of_get_numa_nid(unsigned long node)
+{
+ int length;
+ const __be32 *of_numa_prop;
+
+ of_numa_prop = of_get_flat_dt_prop(node, OF_NUMA_PROP, &length);
+
+ return of_numa_prop_to_nid(of_numa_prop, length);
+}
+
+/* Walk the device tree upwards, looking for a numa-node-id property */
+int of_node_to_nid(struct device_node *device)
+{
+ struct device_node *parent;
+ int nid = NUMA_NO_NODE;
+
+ of_node_get(device);
+ while (device) {
+ const __be32 *of_numa_prop;
+ int length;
+
+ of_numa_prop = of_get_property(device, OF_NUMA_PROP, &length);
+ if (of_numa_prop) {
+ nid = of_numa_prop_to_nid(of_numa_prop, length);
+ break;
+ }
+
+ parent = device;
+ device = of_get_parent(parent);
+ of_node_put(parent);
+ }
+ of_node_put(device);
+
+ return nid;
+}
+
+void __init of_numa_set_node_info(unsigned int cpu, struct device_node *device)
+{
+ int nid = DEFAULT_NODE;
+
+ if (device)
+ nid = of_get_numa_nid(device);
+
+ cpu_to_node_map[cpu] = nid;
+}
+
+/*
+ * Even though we connect cpus to numa domains later in SMP
+ * init, we need to know the node ids now for all cpus.
+*/
+static int __init early_init_parse_cpu_node(unsigned long node)
+{
+ int nid;
+
+ const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
+
+ /* We are scanning "cpu" nodes only */
+ if (type == NULL)
+ return 0;
+ else if (strcmp(type, "cpu") != 0)
+ return 0;
+
+ nid = early_init_of_get_numa_nid(node);
+
+ if (nid == NUMA_NO_NODE)
+ return -EINVAL;
+
+ node_set(nid, numa_nodes_parsed);
+ return 0;
+}
+
+static int __init early_init_parse_memory_node(unsigned long node)
+{
+ const __be32 *reg, *endp;
+ int length;
+ int nid;
+
+ const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
+
+ /* We are scanning "memory" nodes only */
+ if (type == NULL)
+ return 0;
+ else if (strcmp(type, "memory") != 0)
+ return 0;
+
+ nid = early_init_of_get_numa_nid(node);
+
+ if (nid == NUMA_NO_NODE)
+ return -EINVAL;
+
+ reg = of_get_flat_dt_prop(node, "reg", &length);
+ endp = reg + (length / sizeof(__be32));
+
+ while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
+ u64 base, size;
+
+ base = dt_mem_next_cell(dt_root_addr_cells, ®);
+ size = dt_mem_next_cell(dt_root_size_cells, ®);
+ pr_debug("NUMA-DT: base = %llx , node = %u\n",
+ base, nid);
+
+ if (numa_add_memblk(nid, base, size) < 0)
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int __init early_init_parse_distance_map_v1(unsigned long node,
+ const char *uname)
+{
+
+ const __be32 *prop_dist_matrix;
+ int length = 0, i, matrix_count;
+ int nr_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
+
+ pr_info("NUMA: parsing numa-distance-map-v1\n");
+
+ prop_dist_matrix =
+ of_get_flat_dt_prop(node, "distance-matrix", &length);
+
+ if (!length) {
+ pr_err("NUMA: failed to parse distance-matrix\n");
+ return -ENODEV;
+ }
+
+ matrix_count = ((length / sizeof(__be32)) / (3 * nr_size_cells));
+
+ if ((matrix_count * sizeof(__be32) * 3 * nr_size_cells) != length) {
+ pr_warn("NUMA: invalid distance-matrix length %d\n", length);
+ return -EINVAL;
+ }
+
+ for (i = 0; i < matrix_count; i++) {
+ u32 nodea, nodeb, distance;
+
+ nodea = dt_mem_next_cell(nr_size_cells, &prop_dist_matrix);
+ nodeb = dt_mem_next_cell(nr_size_cells, &prop_dist_matrix);
+ distance = dt_mem_next_cell(nr_size_cells, &prop_dist_matrix);
+ numa_set_distance(nodea, nodeb, distance);
+ pr_debug("NUMA-DT: distance[node%d -> node%d] = %d\n",
+ nodea, nodeb, distance);
+
+ /* Set default distance of node B->A same as A->B */
+ if (nodeb > nodea)
+ numa_set_distance(nodeb, nodea, distance);
+ }
+
+ return 0;
+}
+
+static int __init early_init_parse_distance_map(unsigned long node,
+ const char *uname)
+{
+
+ if (strcmp(uname, "distance-map") != 0)
+ return 0;
+
+ if (of_flat_dt_is_compatible(node, "numa-distance-map-v1"))
+ return early_init_parse_distance_map_v1(node, uname);
+
+ return -EINVAL;
+}
+
+/**
+ * early_init_of_scan_numa_map - parse memory node and map nid to memory range.
+ */
+int __init early_init_of_scan_numa_map(unsigned long node, const char *uname,
+ int depth, void *data)
+{
+ int ret;
+
+ ret = early_init_parse_cpu_node(node);
+
+ if (!ret)
+ ret = early_init_parse_memory_node(node);
+
+ if (!ret)
+ ret = early_init_parse_distance_map(node, uname);
+
+ return ret;
+}
+
+/* DT node mapping is done already early_init_of_scan_memory */
+int __init arm64_of_numa_init(void)
+{
+ return of_scan_flat_dt(early_init_of_scan_numa_map, NULL);
+}
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index d6e7d6a..a2a8c2d 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -520,6 +520,8 @@ static void __init of_parse_and_init_cpus(void)
pr_debug("cpu logical map 0x%llx\n", hwid);
cpu_logical_map(cpu_count) = hwid;
+ /* map logical cpu to node */
+ of_numa_set_node_info(cpu_count, dn);
next:
cpu_count++;
}
diff --git a/arch/arm64/mm/numa.c b/arch/arm64/mm/numa.c
index 050b083..9e8704b 100644
--- a/arch/arm64/mm/numa.c
+++ b/arch/arm64/mm/numa.c
@@ -383,5 +383,13 @@ static int __init dummy_numa_init(void)
*/
void __init arm64_numa_init(void)
{
- numa_init(dummy_numa_init);
+ int ret = -ENODEV;
+
+#ifdef CONFIG_OF_NUMA
+ if (!numa_off)
+ ret = numa_init(arm64_of_numa_init);
+#endif
+
+ if (ret)
+ numa_init(dummy_numa_init);
}
--
1.8.1.4
--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
