core: Add node-style memory reservation to device tree

Linux supports a newer memory reservation layout in the device-tree,
where each reservation is represented by a subnode under a top-level
"reserved-memory" node.

This change adds these nodes, using the mem_region names as the property
names (minus any cell addresses). The reserved-memory node looks like
this:

/ {
	name = "reserved-memory";
	ranges;
	#address-cells = <0x2>;
	#size-cells = <0x2>;

	ibm,firmware-code@30000000 {
		reg = <0x0 0x30000000 0x0 0x200000>;
	};

	ibm,firmware-data@30e00000 {
		reg = <0x0 0x30e00000 0x0 0xc00000>;
	};

	ibm,firmware-stacks@31a00000 {
		reg = <0x0 0x31a00000 0x0 0x8000000>;
	};

	ibm,firmware-allocs-memory@39a00000 {
		reg = <0x0 0x39a00000 0x0 0x1c0200>;
	};

	ibm,firmware-heap@30200000 {
		reg = <0x0 0x30200000 0x0 0xc00000>;
	};
};

We also store a pointer to the reservation nodes in struct mem_region,
so they can be used by other skiboot code.

We keep the property-style reservation information (reserved-names and
reserved-ranges) unchanged.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com>

1 files changed, 27 insertions, 0 deletions

diff --git a/core/mem_region.c b/core/mem_region.c
index ea20c5ef..0a1538dc 100644
--- a/core/mem_region.c
+++ b/core/mem_region.c
@@ -927,11 +927,30 @@ void mem_region_release_unused(void)
 	unlock(&mem_region_lock);
 }
 
+static void mem_region_add_dt_reserved_node(struct dt_node *parent,
+		struct mem_region *region)
+{
+	char *name, *p;
+
+	name = strdup(region->name);
+
+	/* remove any cell addresses in the region name; we have our own cell
+	 * addresses here */
+	p = strchr(name, '@');
+	if (p)
+		*p = '\0';
+
+	region->node = dt_new_addr(parent, name, region->start);
+	dt_add_property_u64s(region->node, "reg", region->start, region->len);
+	free(name);
+}
+
 void mem_region_add_dt_reserved(void)
 {
 	int names_len, ranges_len, len;
 	struct mem_region *region;
 	void *names, *ranges;
+	struct dt_node *node;
 	uint64_t *range;
 	char *name;
 
@@ -944,6 +963,12 @@ void mem_region_add_dt_reserved(void)
 	lock(&mem_region_lock);
 	mem_regions_finalised = true;
 
+	/* establish top-level reservation node */
+	node = dt_new(dt_root, "reserved-memory");
+	dt_add_property_cells(node, "#address-cells", 2);
+	dt_add_property_cells(node, "#size-cells", 2);
+	dt_add_property(node, "ranges", NULL, 0);
+
 	/* First pass: calculate length of property data */
 	list_for_each(&regions, region, list) {
 		if (!region_is_reserved(region))
@@ -969,6 +994,8 @@ void mem_region_add_dt_reserved(void)
 		       (long long)(region->start + region->len - 1),
 		       region->name);
 
+		mem_region_add_dt_reserved_node(node, region);
+
 		range[0] = cpu_to_fdt64(region->start);
 		range[1] = cpu_to_fdt64(region->len);
 		range += 2;