Rework linker scripts.

Having separate linker scripts for all the boards is a bad idea. Most
boards really only need to specify MEMORY and the appropriate
REGION_ALIASES() so that support/ld/common.inc can do its work. Not
having infrastructure for this leads to duplication -- viz. the Maple
Mini linker scripts are identical to the Maple's, and the
olimex_stm32_h103 linker directory is just a symlink to
Maple's. Clearly, the current structure is wrong.

To fix it, instead of having per-board subdirectories of support/ld/,
add per-MEMORY subdirectories of (new) support/ld/stm32/mem/. The
per-board .mk files under support/mk/board-includes/ now reference
these directly, and target-config.mk and the Makefile handle this
appropriately. We move some other stuff around in target-config.mk to
make this all more convenient, and even allow more overriding of the
libmaple defaults on a per-board basis. Custom board hacks will be
easier now.

Unfortunately, lots of duplication under support/ld/stm32/mem/ is
necessary, as the LENGTH attribute in a MEMORY region specification
doesn't support arithmetic expressions, and ld doesn't seem to have
any way to specify MEMORY at the command line (why?!). If we find a
better way than this, we should do it.

If a board (e.g. Maple Native) _does_ really need special
memory-related configuration, you can always put a per-board
subdirectory of support/ld/stm32/mem. We do this here to configure the
heap.

Signed-off-by: Marti Bolivar <mbolivar@leaflabs.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/support/ld/stm32/mem/sram_64k_flash_512k/mem-flash.inc b/support/ld/stm32/mem/sram_64k_flash_512k/mem-flash.inc
new file mode 100644
index 0000000..ddb8876
--- /dev/null
+++ b/support/ld/stm32/mem/sram_64k_flash_512k/mem-flash.inc
@@ -0,0 +1,5 @@
+MEMORY
+{
+  ram (rwx) : ORIGIN = 0x20000C00, LENGTH = 61K
+  rom (rx)  : ORIGIN = 0x08005000, LENGTH = 492K
+}