Added dependencies for eboot.ld and Makefile to Makefile. (#7047)

Updated eboot.ld to not fill with zeros through the CS field
on its way to the CRC.
Added size test to elf2bin.py

Author: earlephilhower

bootloaders/eboot/Makefile

@@ -29,13 +29,13 @@ CFLAGS += $(INC)
 
 CFLAGS += $(UZLIB_FLAGS)
 
-LDFLAGS	+= -nostdlib -Wl,--no-check-sections -Wl,--gc-sections -umain
+LDFLAGS	+= -nostdlib -Wl,--no-check-sections -Wl,--gc-sections -umain -Wl,-Map,$(@:.elf=.map)
 
 LD_SCRIPT := -Teboot.ld
 
-APP_OUT:= eboot.elf
-APP_AR := eboot.a
-APP_FW := eboot.bin
+APP_OUT := eboot.elf
+APP_AR  := eboot.a
+APP_FW  := eboot.bin
 
 
 all: $(APP_OUT)
@@ -49,13 +49,14 @@ tinfgzip.o: $(UZLIB_PATH)/tinfgzip.c $(UZLIB_PATH)/uzlib.h $(UZLIB_PATH)/uzlib_c
 $(APP_AR): $(TARGET_OBJ_PATHS) tinflate.o tinfgzip.o
 	$(AR) cru $@ $^
 
-$(APP_OUT): $(APP_AR)
+$(APP_OUT): $(APP_AR) eboot.ld | Makefile
 	$(LD) $(LD_SCRIPT) $(LDFLAGS) -Wl,--start-group -Wl,--whole-archive $(APP_AR) -Wl,--end-group -o $@
 
 clean:
 	rm -f *.o
 	rm -f $(APP_AR)
 	rm -f $(APP_OUT)
+	rm -f *.map
 
 
 .PHONY: all clean default

bootloaders/eboot/eboot.elf

@@ -154,12 +154,24 @@ SECTIONS
     *(.gnu.linkonce.b.*)
     . = ALIGN (8);
     _bss_end = ABSOLUTE(.);
-    /* CRC stored in last 8 bytes */
-    ASSERT((. < 4096 - 8), "Error: No space for CRC in bootloader sector.");
-    . = _stext + 4096 - 8;
-    _crc_size = .;
-    . = . + 4;
-    _crc_val = .;
+    _free_space = 4096 - 17 - (. - _stext);
+/*
+The boot loader checksum must be before the CRC, which is written by elf2bin.py.
+This leaves 16 bytes after the checksum for the CRC placed at the end of the
+4096-byte sector. */
+    _cs_here = (ALIGN((. + 1), 16) == ALIGN(16)) ? (ALIGN(16) - 1) : (. + 0x0F);
+
+/*
+The filling (padding) and values for _crc_size and _crc_val are handled by
+elf2bin.py. With this, we give values to the symbols without explicitly
+assigning space. This avoids the linkers back *fill* operation that causes
+trouble.
+
+The CRC info is stored in last 8 bytes.    */
+    _crc_size = _stext + 4096 - 8;
+    _crc_val = _stext + 4096 - 4;
+    ASSERT((4096 > (17 + (. - _stext))), "Error: No space for CS and CRC in bootloader sector.");
+    ASSERT((_crc_size > _cs_here), "Error: CRC must be located after CS.");
   } >iram1_0_seg :iram1_0_phdr
 
   .lit4 : ALIGN(4)

bootloaders/eboot/eboot.ld

@@ -93,6 +93,8 @@ def write_bin(out, elf, segments, to_addr, flash_mode, flash_size, flash_freq, p
         out.write(bytearray([0]))
     out.write(bytearray([checksum]))
     if to_addr != 0:
+        if total_size + 8 > to_addr:
+            raise Exception('Bin image of ' + elf + ' is too big, actual size ' + str(total_size  + 8) + ', target size ' + str(to_addr) + '.')
         while total_size < to_addr:
             out.write(bytearray([0xaa]))
             total_size += 1