altos/stm: Create per-product flash loaders

[fw/altos] / src / stm / altos-loader.ld

diff --git a/src/stm/altos-loader.ld b/src/stm/altos-loader.ld
index 50a425c75309f2cf203bf25d200f50e2706cbcfe..2be964f2a7bad6bc5598ac9a249085273ace66c5 100644 (file)
--- a/src/stm/altos-loader.ld
+++ b/src/stm/altos-loader.ld
@@ -16,7 +16,7 @@
  */
 
 MEMORY {
-       rom : ORIGIN = 0x08000000, LENGTH = 8K
+       rom : ORIGIN = 0x08000000, LENGTH = 4K
        ram : ORIGIN = 0x20000000, LENGTH = 16K
 }
 
@@ -37,33 +37,46 @@ SECTIONS {
 
                ao_romconfig.o(.romconfig*)
                ao_product.o(.romconfig*)
-
                *(.text)        /* Executable code */
-               *(.rodata)      /* Constants */
-
-       } > rom
-
-       .ARM.exidx : {
                *(.ARM.exidx* .gnu.linkonce.armexidx.*)
+               *(.rodata*)     /* Constants */
+               __text_end__ = .;
        } > rom
-       __text_end__ = .;
 
-       /* Functions placed in RAM (required for flashing) */
-       .textram : {
-               __text_ram_start = .;
+       /* Boot data which must live at the start of ram so that
+        * the application and bootloader share the same addresses.
+        * This must be all uninitialized data
+        */
+       .boot (NOLOAD) : {
+               __boot_start__ = .;
+               *(.boot)
+               __boot_end__ = .;
+       } >ram
+
+       /* Functions placed in RAM (required for flashing)
+        *
+        * Align to 8 bytes as that's what the ARM likes text
+        * segment alignments to be, and if we don't, then
+        * we end up with a mismatch between the location in
+        * ROM and the desired location in RAM. I don't
+        * entirely understand this, but at least this appears
+        * to work...
+        */
+
+       .textram BLOCK(8): {
                __data_start__ = .;
+               __text_ram_start__ = .;
                *(.text.ram)
-               . = ALIGN(4);
+               __text_ram_end = .;
        } >ram AT>rom
-       __text_ram_end = .;
 
        /* Data -- relocated to RAM, but written to ROM
         */
        .data : {
                *(.data)        /* initialized data */
-               . = ALIGN (4);
+               __data_end__ = .;
        } >ram AT>rom
-       __data_end__ = .;
+
 
        .bss : {
                __bss_start__ = .;