MIPS: sead3: populate platform devices from device tree

[cascardo/linux.git] / arch / mips / mti-sead3 / sead3-setup.c

diff --git a/arch/mips/mti-sead3/sead3-setup.c b/arch/mips/mti-sead3/sead3-setup.c
index 928ba84..541a907 100644 (file)
--- a/arch/mips/mti-sead3/sead3-setup.c
+++ b/arch/mips/mti-sead3/sead3-setup.c
@@ -4,13 +4,16 @@
  * 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>
 
@@ -19,8 +22,73 @@ const char *get_system_type(void)
        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
@@ -43,3 +111,10 @@ void __init device_tree_init(void)
 
        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);