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-rw-r--r--drivers/of/fdt.c131
1 files changed, 131 insertions, 0 deletions
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index 758b4f8b30b7..819e11209718 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -15,6 +15,7 @@
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_fdt.h>
+#include <linux/sizes.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/slab.h>
@@ -440,6 +441,118 @@ struct boot_param_header *initial_boot_params;
#ifdef CONFIG_OF_EARLY_FLATTREE
/**
+ * res_mem_reserve_reg() - reserve all memory described in 'reg' property
+ */
+static int __init __reserved_mem_reserve_reg(unsigned long node,
+ const char *uname)
+{
+ int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
+ phys_addr_t base, size;
+ unsigned long len;
+ __be32 *prop;
+ int nomap;
+
+ prop = of_get_flat_dt_prop(node, "reg", &len);
+ if (!prop)
+ return -ENOENT;
+
+ if (len && len % t_len != 0) {
+ pr_err("Reserved memory: invalid reg property in '%s', skipping node.\n",
+ uname);
+ return -EINVAL;
+ }
+
+ nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
+
+ while (len >= t_len) {
+ base = dt_mem_next_cell(dt_root_addr_cells, &prop);
+ size = dt_mem_next_cell(dt_root_size_cells, &prop);
+
+ if (base && size &&
+ early_init_dt_reserve_memory_arch(base, size, nomap) == 0)
+ pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %ld MiB\n",
+ uname, &base, (unsigned long)size / SZ_1M);
+ else
+ pr_info("Reserved memory: failed to reserve memory for node '%s': base %pa, size %ld MiB\n",
+ uname, &base, (unsigned long)size / SZ_1M);
+
+ len -= t_len;
+ }
+ return 0;
+}
+
+/**
+ * __reserved_mem_check_root() - check if #size-cells, #address-cells provided
+ * in /reserved-memory matches the values supported by the current implementation,
+ * also check if ranges property has been provided
+ */
+static int __reserved_mem_check_root(unsigned long node)
+{
+ __be32 *prop;
+
+ prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
+ if (!prop || be32_to_cpup(prop) != dt_root_size_cells)
+ return -EINVAL;
+
+ prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
+ if (!prop || be32_to_cpup(prop) != dt_root_addr_cells)
+ return -EINVAL;
+
+ prop = of_get_flat_dt_prop(node, "ranges", NULL);
+ if (!prop)
+ return -EINVAL;
+ return 0;
+}
+
+/**
+ * fdt_scan_reserved_mem() - scan a single FDT node for reserved memory
+ */
+static int __init __fdt_scan_reserved_mem(unsigned long node, const char *uname,
+ int depth, void *data)
+{
+ static int found;
+ const char *status;
+
+ if (!found && depth == 1 && strcmp(uname, "reserved-memory") == 0) {
+ if (__reserved_mem_check_root(node) != 0) {
+ pr_err("Reserved memory: unsupported node format, ignoring\n");
+ /* break scan */
+ return 1;
+ }
+ found = 1;
+ /* scan next node */
+ return 0;
+ } else if (!found) {
+ /* scan next node */
+ return 0;
+ } else if (found && depth < 2) {
+ /* scanning of /reserved-memory has been finished */
+ return 1;
+ }
+
+ status = of_get_flat_dt_prop(node, "status", NULL);
+ if (status && strcmp(status, "okay") != 0 && strcmp(status, "ok") != 0)
+ return 0;
+
+ __reserved_mem_reserve_reg(node, uname);
+
+ /* scan next node */
+ return 0;
+}
+
+/**
+ * early_init_fdt_scan_reserved_mem() - create reserved memory regions
+ *
+ * This function grabs memory from early allocator for device exclusive use
+ * defined in device tree structures. It should be called by arch specific code
+ * once the early allocator (i.e. memblock) has been fully activated.
+ */
+void __init early_init_fdt_scan_reserved_mem(void)
+{
+ of_scan_flat_dt(__fdt_scan_reserved_mem, NULL);
+}
+
+/**
* of_scan_flat_dt - scan flattened tree blob and call callback on each.
* @it: callback function
* @data: context data pointer
@@ -856,6 +969,16 @@ void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size)
memblock_add(base, size);
}
+int __init __weak early_init_dt_reserve_memory_arch(phys_addr_t base,
+ phys_addr_t size, bool nomap)
+{
+ if (memblock_is_region_reserved(base, size))
+ return -EBUSY;
+ if (nomap)
+ return memblock_remove(base, size);
+ return memblock_reserve(base, size);
+}
+
/*
* called from unflatten_device_tree() to bootstrap devicetree itself
* Architectures can override this definition if memblock isn't used
@@ -864,6 +987,14 @@ void * __init __weak early_init_dt_alloc_memory_arch(u64 size, u64 align)
{
return __va(memblock_alloc(size, align));
}
+#else
+int __init __weak early_init_dt_reserve_memory_arch(phys_addr_t base,
+ phys_addr_t size, bool nomap)
+{
+ pr_err("Reserved memory not supported, ignoring range 0x%llx - 0x%llx%s\n",
+ base, size, nomap ? " (nomap)" : "");
+ return -ENOSYS;
+}
#endif
bool __init early_init_dt_scan(void *params)