--- zzzz-none-000/linux-3.10.107/arch/mips/mti-sead3/sead3-setup.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/arch/mips/mti-sead3/sead3-setup.c	2021-02-04 17:41:59.000000000 +0000
@@ -4,11 +4,15 @@
  * for more details.
  *
  * Copyright (C) 2012 MIPS Technologies, Inc.  All rights reserved.
+ * Copyright (C) 2013 Imagination Technologies Ltd.
  */
 #include <linux/init.h>
+#include <linux/libfdt.h>
 #include <linux/of_platform.h>
 #include <linux/of_fdt.h>
-#include <linux/bootmem.h>
+
+#include <asm/prom.h>
+#include <asm/fw/fw.h>
 
 #include <asm/mips-boards/generic.h>
 
@@ -17,27 +21,91 @@
 	return "MIPS SEAD3";
 }
 
+static uint32_t get_memsize_from_cmdline(void)
+{
+	int memsize = 0;
+	char *p = arcs_cmdline;
+	char *s = "memsize=";
+
+	p = strstr(p, s);
+	if (p) {
+		p += strlen(s);
+		memsize = memparse(p, NULL);
+	}
+
+	return memsize;
+}
+
+static uint32_t get_memsize_from_env(void)
+{
+	int memsize = 0;
+	char *p;
+
+	p = fw_getenv("memsize");
+	if (p)
+		memsize = memparse(p, NULL);
+
+	return memsize;
+}
+
+static uint32_t get_memsize(void)
+{
+	uint32_t memsize;
+
+	memsize = get_memsize_from_cmdline();
+	if (memsize)
+		return memsize;
+
+	return get_memsize_from_env();
+}
+
+static void __init parse_memsize_param(void)
+{
+	int offset;
+	const uint64_t *prop_value;
+	int prop_len;
+	uint32_t memsize = get_memsize();
+
+	if (!memsize)
+		return;
+
+	offset = fdt_path_offset(__dtb_start, "/memory");
+	if (offset > 0) {
+		uint64_t new_value;
+		/*
+		 * reg contains 2 32-bits BE values, offset and size. We just
+		 * want to replace the size value without affecting the offset
+		 */
+		prop_value = fdt_getprop(__dtb_start, offset, "reg", &prop_len);
+		new_value = be64_to_cpu(*prop_value);
+		new_value =  (new_value & ~0xffffffffllu) | memsize;
+		fdt_setprop_inplace_u64(__dtb_start, offset, "reg", new_value);
+	}
+}
+
 void __init plat_mem_setup(void)
 {
+	/* allow command line/bootloader env to override memory size in DT */
+	parse_memsize_param();
+
 	/*
 	 * Load the builtin devicetree. This causes the chosen node to be
 	 * parsed resulting in our memory appearing
 	 */
-	__dt_setup_arch(&__dtb_start);
+	__dt_setup_arch(__dtb_start);
 }
 
 void __init device_tree_init(void)
 {
-	unsigned long base, size;
-
 	if (!initial_boot_params)
 		return;
 
-	base = virt_to_phys((void *)initial_boot_params);
-	size = be32_to_cpu(initial_boot_params->totalsize);
-
-	/* Before we do anything, lets reserve the dt blob */
-	reserve_bootmem(base, size, BOOTMEM_DEFAULT);
+	unflatten_and_copy_device_tree();
+}
 
-	unflatten_device_tree();
+static int __init customize_machine(void)
+{
+	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
+	return 0;
 }
+arch_initcall(customize_machine);