Merge remote-tracking branches 'asoc/topic/adau1977', 'asoc/topic/ak4642', 'asoc...

[sfrench/cifs-2.6.git] / drivers / of / fdt.c

diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index b777d8f46bd59696e366f957c27211411b32ef76..9aa012e6ea0a6ed988150624bacc0eb2b8066c06 100644 (file)
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -26,6 +26,54 @@
 #include <asm/setup.h>  /* for COMMAND_LINE_SIZE */
 #include <asm/page.h>
 
+/*
+ * of_fdt_limit_memory - limit the number of regions in the /memory node
+ * @limit: maximum entries
+ *
+ * Adjust the flattened device tree to have at most 'limit' number of
+ * memory entries in the /memory node. This function may be called
+ * any time after initial_boot_param is set.
+ */
+void of_fdt_limit_memory(int limit)
+{
+       int memory;
+       int len;
+       const void *val;
+       int nr_address_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
+       int nr_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
+       const uint32_t *addr_prop;
+       const uint32_t *size_prop;
+       int root_offset;
+       int cell_size;
+
+       root_offset = fdt_path_offset(initial_boot_params, "/");
+       if (root_offset < 0)
+               return;
+
+       addr_prop = fdt_getprop(initial_boot_params, root_offset,
+                               "#address-cells", NULL);
+       if (addr_prop)
+               nr_address_cells = fdt32_to_cpu(*addr_prop);
+
+       size_prop = fdt_getprop(initial_boot_params, root_offset,
+                               "#size-cells", NULL);
+       if (size_prop)
+               nr_size_cells = fdt32_to_cpu(*size_prop);
+
+       cell_size = sizeof(uint32_t)*(nr_address_cells + nr_size_cells);
+
+       memory = fdt_path_offset(initial_boot_params, "/memory");
+       if (memory > 0) {
+               val = fdt_getprop(initial_boot_params, memory, "reg", &len);
+               if (len > limit*cell_size) {
+                       len = limit*cell_size;
+                       pr_debug("Limiting number of entries to %d\n", limit);
+                       fdt_setprop(initial_boot_params, memory, "reg", val,
+                                       len);
+               }
+       }
+}
+
 /**
  * of_fdt_is_compatible - Return true if given node from the given blob has
  * compat in its compatible list
@@ -937,7 +985,7 @@ int __init __weak early_init_dt_reserve_memory_arch(phys_addr_t base,
 }
 #endif
 
-bool __init early_init_dt_scan(void *params)
+bool __init early_init_dt_verify(void *params)
 {
        if (!params)
                return false;
@@ -951,6 +999,12 @@ bool __init early_init_dt_scan(void *params)
                return false;
        }
 
+       return true;
+}
+
+
+void __init early_init_dt_scan_nodes(void)
+{
        /* Retrieve various information from the /chosen node */
        of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
 
@@ -959,7 +1013,17 @@ bool __init early_init_dt_scan(void *params)
 
        /* Setup memory, calling early_init_dt_add_memory_arch */
        of_scan_flat_dt(early_init_dt_scan_memory, NULL);
+}
+
+bool __init early_init_dt_scan(void *params)
+{
+       bool status;
+
+       status = early_init_dt_verify(params);
+       if (!status)
+               return false;
 
+       early_init_dt_scan_nodes();
        return true;
 }