MIPS: bootm: refactor preparation of Linux kernel environment

Move preparation of Linux kernel environment in a separate
function and mark it as legacy. Add a Kconfig option to make
that legacy mode configurable.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>

arch/mips/Kconfig

@@ -127,6 +127,15 @@ config MIPS_BOOT_CMDLINE_LEGACY
 	  compatible list. The argument count (argc) is stored in register $a0.
 	  The address of the argument list (argv) is stored in register $a1.
 
+config MIPS_BOOT_ENV_LEGACY
+	bool "Hand over legacy environment to Linux kernel"
+	default y
+	help
+	  Enable this option if you want U-Boot to hand over the Yamon-style
+	  environment to the kernel. Information like memory size, initrd
+	  address and size will be prepared as zero-terminated key/value list.
+	  The address of the enviroment is stored in register $a2.
+
 endmenu
 
 config SUPPORTS_BIG_ENDIAN

arch/mips/lib/bootm.c

@@ -26,6 +26,12 @@ DECLARE_GLOBAL_DATA_PTR;
 #define mips_boot_cmdline_legacy	0
 #endif
 
+#if defined(CONFIG_MIPS_BOOT_ENV_LEGACY)
+#define mips_boot_env_legacy	1
+#else
+#define mips_boot_env_legacy	0
+#endif
+
 static int linux_argc;
 static char **linux_argv;
 static char *linux_argp;
@@ -177,7 +183,7 @@ static void linux_env_set(const char *env_name, const char *env_val)
 	}
 }
 
-static void boot_prep_linux(bootm_headers_t *images)
+static void linux_env_legacy(bootm_headers_t *images)
 {
 	char env_buf[12];
 	const char *cp;
@@ -225,6 +231,12 @@ static void boot_prep_linux(bootm_headers_t *images)
 	}
 }
 
+static void boot_prep_linux(bootm_headers_t *images)
+{
+	if (mips_boot_env_legacy)
+		linux_env_legacy(images);
+}
+
 static void boot_jump_linux(bootm_headers_t *images)
 {
 	typedef void __noreturn (*kernel_entry_t)(int, ulong, ulong, ulong);