[PATCH v2 6/8] pbl: fdt: add support to parse reserved mem

[Rouven Czerwinski]

This allows the PBL to fill a reserved memory map which a subsequent
commit will use modify the early MMU mapping.

Signed-off-by: Rouven Czerwinski <r.czerwinski at pengutronix.de>
---
 include/pbl.h |  25 ++++++++++++
 pbl/fdt.c     | 103 ++++++++++++++++++++++++++++++++++++++++++--------
 2 files changed, 113 insertions(+), 15 deletions(-)

diff --git a/include/pbl.h b/include/pbl.h
index f58daec735..03272879d7 100644
--- a/include/pbl.h
+++ b/include/pbl.h
@@ -42,5 +42,30 @@ struct fdt_device_id {
 const void *
 fdt_device_get_match_data(const void *fdt, const char *nodepath,
 			  const struct fdt_device_id ids[]);
+struct pbl_reserved_memory {
+	phys_addr_t			base;
+	phys_addr_t			size;
+	unsigned int			flags;
+};
+
+#define MAX_RESERVED_REGIONS	8
+
+#define FDT_RES_MEM_FLAG_NOMAP		BIT(0)
+
+void fdt_fill_reserve_mem(const void *fdt);
+
+#ifdef CONFIG_LIBFDT
+const struct pbl_reserved_memory *get_pbl_reserved_memory(void);
+int get_pbl_reserved_memory_num(void);
+#else
+static inline const struct pbl_reserved_memory *get_pbl_reserved_memory(void)
+{
+	return NULL;
+}
+static inline int get_pbl_reserved_memory_num(void)
+{
+	return 0;
+}
+#endif
 
 #endif /* __PBL_H__ */
diff --git a/pbl/fdt.c b/pbl/fdt.c
index 18ddb9f48a..383d0fec74 100644
--- a/pbl/fdt.c
+++ b/pbl/fdt.c
@@ -5,8 +5,8 @@
 
 void fdt_find_mem(const void *fdt, unsigned long *membase, unsigned long *memsize)
 {
-	const __be32 *nap, *nsp, *reg;
-	uint32_t na, ns;
+	const __be32 *reg;
+	int na, ns;
 	uint64_t memsize64, membase64;
 	int node, size, i;
 
@@ -16,26 +16,17 @@ void fdt_find_mem(const void *fdt, unsigned long *membase, unsigned long *memsiz
 		goto err;
 	}
 
-	/* Find the #address-cells and #size-cells properties */
-	node = fdt_path_offset(fdt, "/");
-	if (node < 0) {
-		pr_err("Cannot find root node\n");
-		goto err;
-	}
-
-	nap = fdt_getprop(fdt, node, "#address-cells", &size);
-	if (!nap || (size != 4)) {
+	na = fdt_address_cells(fdt, 0);
+	if (na < 0) {
 		pr_err("Cannot find #address-cells property");
 		goto err;
 	}
-	na = fdt32_to_cpu(*nap);
 
-	nsp = fdt_getprop(fdt, node, "#size-cells", &size);
-	if (!nsp || (size != 4)) {
+	ns = fdt_size_cells(fdt, 0);
+	if (ns < 0) {
 		pr_err("Cannot find #size-cells property");
 		goto err;
 	}
-	ns = fdt32_to_cpu(*nap);
 
 	/* Find the memory range */
 	node = fdt_node_offset_by_prop_value(fdt, -1, "device_type",
@@ -103,3 +94,85 @@ const void *fdt_device_get_match_data(const void *fdt, const char *nodepath,
 
 	return NULL;
 }
+
+static struct pbl_reserved_memory reserved_mem[MAX_RESERVED_REGIONS];
+static int reserved_mem_count;
+
+void fdt_fill_reserve_mem(const void *fdt)
+{
+	const __be32 *nap, *nsp, *reg;
+	uint32_t na, ns;
+	int node, size, i, parent;
+	const void *prop;
+	uint64_t memsize64, membase64;
+	bool nomap;
+
+	/* Make sure FDT blob is sane */
+	if (fdt_check_header(fdt) != 0) {
+		pr_err("Invalid device tree blob\n");
+		return;
+	}
+
+	parent = fdt_path_offset(fdt, "/reserved-memory");
+	if (parent < 0) {
+		pr_info("Cannot find reserved-memory node\n");
+		return;
+	}
+
+	nap = fdt_getprop(fdt, parent, "#address-cells", &size);
+	if (!nap || (size != 4)) {
+		pr_err("Cannot find #address-cells property");
+		return;
+	}
+	na = fdt32_to_cpu(*nap);
+
+	nsp = fdt_getprop(fdt, parent, "#size-cells", &size);
+	if (!nsp || (size != 4)) {
+		pr_err("Cannot find #size-cells property");
+		return;
+	}
+	ns = fdt32_to_cpu(*nap);
+
+	fdt_for_each_subnode(node, fdt, parent) {
+		nomap = true;
+		reg = fdt_getprop(fdt, node, "reg", &size);
+		if (size < (na + ns) * sizeof(u32)) {
+			pr_err("cannot get memory range\n");
+			return;
+		}
+
+		membase64 = 0;
+		for (i = 0; i < na; i++)
+			membase64 = (membase64 << 32) | fdt32_to_cpu(*reg++);
+
+		/* get the memsize and truncate it to under 4G on 32 bit machines */
+		memsize64 = 0;
+		for (i = 0; i < ns; i++)
+			memsize64 = (memsize64 << 32) | fdt32_to_cpu(*reg++);
+
+		prop = fdt_getprop(fdt, node, "nomap", NULL);
+		if (!prop)
+			nomap = false;
+
+		reserved_mem[reserved_mem_count].base = membase64;
+		reserved_mem[reserved_mem_count].size = memsize64;
+		if (nomap)
+			reserved_mem[reserved_mem_count].flags |= FDT_RES_MEM_FLAG_NOMAP;
+		reserved_mem_count++;
+	}
+
+	if ((node < 0) && (node != -FDT_ERR_NOTFOUND)) {
+		pr_err("Error while parsing reserved-memory nodes: %d\n", node);
+		return;
+	}
+}
+
+const struct pbl_reserved_memory *get_pbl_reserved_memory(void)
+{
+	return reserved_mem;
+}
+
+int get_pbl_reserved_memory_num(void)
+{
+	return reserved_mem_count;
+}
-- 
2.32.0