Add MK20DX256 ld script with 8 KB bootloader

os/common/startup/ARMCMx/compilers/GCC/ld/MK20DX256BLDR8.ld

@@ -0,0 +1,56 @@
+/*
+ * Copyright (C) 2013-2016 Fabio Utzig, http://fabioutzig.com
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+/*
+ * MK20DX256 memory setup (8k bootloader section).
+ */
+MEMORY
+{
+  flash    : org = 0x00002000, len = 256k - 0x2000
+  ram0     : org = 0x1FFF8000, len = 64k
+  ram1     : org = 0x00000000, len = 0
+  ram2     : org = 0x00000000, len = 0
+  ram3     : org = 0x00000000, len = 0
+  ram4     : org = 0x00000000, len = 0
+  ram5     : org = 0x00000000, len = 0
+  ram6     : org = 0x00000000, len = 0
+  ram7     : org = 0x00000000, len = 0
+}
+
+/* RAM region to be used for Main stack. This stack accommodates the processing
+   of all exceptions and interrupts*/
+REGION_ALIAS("MAIN_STACK_RAM", ram0);
+
+/* RAM region to be used for the process stack. This is the stack used by
+   the main() function.*/
+REGION_ALIAS("PROCESS_STACK_RAM", ram0);
+
+/* RAM region to be used for data segment.*/
+REGION_ALIAS("DATA_RAM", ram0);
+
+/* RAM region to be used for BSS segment.*/
+REGION_ALIAS("BSS_RAM", ram0);
+
+/* RAM region to be used for the default heap.*/
+REGION_ALIAS("HEAP_RAM", ram0);
+
+INCLUDE rules_kinetis_bldr.ld