build: add firmware0 target (firmware with no headers)

Makefile

@@ -72,6 +72,7 @@ build_bootloader: ## build bootloader
 
 build_firmware: res build_cross ## build firmware with frozen modules
 	$(SCONS) CFLAGS="$(CFLAGS)" build/firmware/firmware.bin
+	$(SCONS) CFLAGS="$(CFLAGS)" build/firmware/firmware0.bin
 
 build_unix: ## build unix port
 	$(SCONS) build/unix/micropython $(UNIX_PORT_OPTS)
@@ -114,6 +115,9 @@ flash_bootloader: ## flash bootloader using st-flash
 flash_firmware: ## flash firmware using st-flash
 	st-flash write $(FIRMWARE_BUILD_DIR)/firmware.bin 0x08020000
 
+flash_firmware0: ## flash firmware0 using st-flash
+	st-flash write $(FIRMWARE_BUILD_DIR)/firmware0.bin 0x08000000
+
 flash_combine: ## flash combined image using st-flash
 	st-flash write $(FIRMWARE_BUILD_DIR)/combined.bin 0x08000000
 
@@ -144,6 +148,7 @@ sizecheck: ## check sizes of binary files
 	test 32768 -ge $(shell stat -c%s $(BOARDLOADER_BUILD_DIR)/boardloader.bin)
 	test 65536 -ge $(shell stat -c%s $(BOOTLOADER_BUILD_DIR)/bootloader.bin)
 	test 917504 -ge $(shell stat -c%s $(FIRMWARE_BUILD_DIR)/firmware.bin)
+	test 1048576 -ge $(shell stat -c%s $(FIRMWARE_BUILD_DIR)/firmware0.bin)
 
 combine: ## combine boardloader + bootloader + firmware into one combined image
 	./tools/combine_firmware \

SConscript.firmware

@@ -326,6 +326,7 @@ env.Replace(
     CCFLAGS_QSTR='-DNO_QSTR -DN_X64 -DN_X86 -DN_THUMB',
     CCFLAGS_OPT='-O3',
     LINKFLAGS='-nostdlib -T embed/firmware/memory.ld --gc-sections',
+    LINKFLAGS0='-nostdlib -T embed/firmware/memory0.ld --gc-sections',
     CPPPATH=[
         '.',
         'embed/firmware',
@@ -421,6 +422,13 @@ program_elf = env.Command(
     '$LINK -o $TARGET $LINKFLAGS $SOURCES `$CC $CFLAGS $CCFLAGS $_CCCOMCOM -print-libgcc-file-name`',
 )
 
+program0_elf = env.Command(
+    target='firmware0.elf',
+    source=obj_program,
+    action=
+    '$LINK -o $TARGET $LINKFLAGS0 $SOURCES `$CC $CFLAGS $CCFLAGS $_CCCOMCOM -print-libgcc-file-name`',
+)
+
 program_bin = env.Command(
     target='firmware.bin',
     source=program_elf,
@@ -428,3 +436,10 @@ program_bin = env.Command(
         '$OBJCOPY -O binary -j .header -j .flash -j .data $SOURCE $TARGET',
         '$BINCTL $TARGET -s 1 4141414141414141414141414141414141414141414141414141414141414141',
     ], )
+
+program0_bin = env.Command(
+    target='firmware0.bin',
+    source=program0_elf,
+    action=[
+        '$OBJCOPY -O binary -j .flash -j .data $SOURCE $TARGET',
+    ], )

embed/firmware/memory0.ld

@@ -0,0 +1,93 @@
+/*
+    TREZORv2 linker script
+    based on common.ld and stm32f405.ld
+*/
+
+/* Specify the memory areas */
+MEMORY
+{
+    FLASH (rx)      : ORIGIN = 0x08000000, LENGTH =  1024K
+    CCMRAM (xrw)    : ORIGIN = 0x10000000, LENGTH =    64K
+    RAM (xrw)       : ORIGIN = 0x20000000, LENGTH =   128K
+}
+
+/* produce a link error if there is not this amount of RAM for these sections */
+_minimum_stack_size = 2K;
+_minimum_heap_size = 16K;
+
+/* Define tho top end of the stack.  The stack is full descending so begins just
+   above last byte of RAM.  Note that EABI requires the stack to be 8-byte
+   aligned for a call. */
+_estack = ORIGIN(RAM) + LENGTH(RAM);
+
+ENTRY(Reset_Handler)
+
+/* define output sections */
+SECTIONS
+{
+    /* The startup code goes first into FLASH */
+    .flash :
+    {
+        . = ALIGN(4);
+        KEEP(*(.isr_vector)) /* Startup code */
+        . = ALIGN(4);
+        *(.text*)          /* .text* sections (code) */
+        *(.rodata*)        /* .rodata* sections (constants, strings, etc.) */
+        . = ALIGN(512);
+        _etext = .;        /* define a global symbol at end of code */
+    } >FLASH
+
+    /* used by the startup to initialize data */
+    _sidata = LOADADDR(.data);
+
+    /* This is the initialized data section
+    The program executes knowing that the data is in the RAM
+    but the loader puts the initial values in the FLASH (inidata).
+    It is one task of the startup to copy the initial values from FLASH to RAM. */
+    .data :
+    {
+        . = ALIGN(4);
+        _sdata = .;        /* create a global symbol at data start; used by startup code in order to initialise the .data section in RAM */
+        *(.data*)          /* .data* sections */
+
+        . = ALIGN(512);
+        _edata = .;        /* define a global symbol at data end; used by startup code in order to initialise the .data section in RAM */
+    } >RAM AT> FLASH
+
+    /* Uninitialized data section */
+    .bss :
+    {
+        . = ALIGN(4);
+        _sbss = .;         /* define a global symbol at bss start; used by startup code */
+        *(.bss*)
+        *(COMMON)
+
+        . = ALIGN(4);
+        _ebss = .;         /* define a global symbol at bss end; used by startup code and GC */
+    } >RAM
+
+    /* this is to define the start of the heap, and make sure we have a minimum size */
+    .heap :
+    {
+        . = ALIGN(4);
+        . = . + _minimum_heap_size;
+        . = ALIGN(4);
+    } >RAM
+
+    /* this just checks there is enough RAM for the stack */
+    .stack :
+    {
+        . = ALIGN(4);
+        . = . + _minimum_stack_size;
+        . = ALIGN(4);
+    } >RAM
+
+    .ARM.attributes 0 : { *(.ARM.attributes) }
+}
+
+/* RAM extents for the garbage collector */
+_codelen = SIZEOF(.flash) + SIZEOF(.data);
+_ram_start = ORIGIN(RAM);
+_ram_end = ORIGIN(RAM) + LENGTH(RAM);
+_heap_start = _ebss; /* heap starts just after statically allocated memory */
+_heap_end = 0x2001c000; /* tunable */