# include module specific includes
INCLUDES += -I$(RIOTCPU)/cortexm_common/include

# All variables must be defined in the CPU configuration when using the common
# `ldscripts/cortexm.ld`
ifneq (,$(ROM_START_ADDR)$(RAM_START_ADDR)$(ROM_LEN)$(RAM_LEN))
  $(if $(ROM_START_ADDR),,$(error ROM_START_ADDR is not defined))
  $(if $(RAM_START_ADDR),,$(error RAM_START_ADDR is not defined))
  $(if $(ROM_LEN),,$(error ROM_LEN is not defined))
  $(if $(RAM_LEN),,$(error RAM_LEN is not defined))
  LINKFLAGS += $(LINKFLAGPREFIX)--defsym=_rom_start_addr=$(ROM_START_ADDR)
  LINKFLAGS += $(LINKFLAGPREFIX)--defsym=_ram_start_addr=$(RAM_START_ADDR)
  LINKFLAGS += $(LINKFLAGPREFIX)--defsym=_rom_length=$(ROM_LEN)
  LINKFLAGS += $(LINKFLAGPREFIX)--defsym=_ram_length=$(RAM_LEN)
endif

ifneq (,$(BACKUP_RAM_LEN))
  LINKFLAGS += $(LINKFLAGPREFIX)--defsym=_backup_ram_start_addr=$(BACKUP_RAM_ADDR)
  LINKFLAGS += $(LINKFLAGPREFIX)--defsym=_backup_ram_len=$(BACKUP_RAM_LEN)
  CFLAGS    += -DCPU_HAS_BACKUP_RAM=1
endif

TOOLCHAINS_SUPPORTED = gnu llvm

# Only define the linker symbol if the variable is set
# The variable can be set using target specific variable thanks to lazy evaluation

# ROM_OFFSET: offset in rom to start linking, allows supporting a bootloader
LINKFLAGS += $(if $(ROM_OFFSET),$(LINKFLAGPREFIX)--defsym=_rom_offset=$(ROM_OFFSET))
# FW_ROM_LEN: rom length to use for firmware linking. Allows linking only in a section of the rom.
LINKFLAGS += $(if $(FW_ROM_LEN),$(LINKFLAGPREFIX)--defsym=_fw_rom_length=$(FW_ROM_LEN))

# Cortex-M riotboot settings

# From ARMv8-M (M23, M33) architecture reference manual, section B3.27
# https://static.docs.arm.com/ddi0553/a/DDI0553A_e_armv8m_arm.pdf
# "In a PE with a configurable vector table base, the vector table must be
# naturally aligned to a power of two, with an alignment value that is:
# * A minimum of 128 bytes.
# * Greater than or equal to (Number of Exceptions supported x4)."

# From ARMv7-M (M4, M4F, M3, M7) architecture reference manual, section B1.5.3
# https://static.docs.arm.com/ddi0403/e/DDI0403E_d_armv7m_arm.pdf
# "The Vector table must be naturally aligned to a power of two whose alignment
# value is greater than or equal to number of Exceptions supported x 4"

# From ARMv6-M (M0, M0+, M1) architecture reference manual, section B1.5.3
# https://static.docs.arm.com/ddi0419/d/DDI0419D_armv6m_arm.pdf
# "The table offset address that VTOR defines is 32-word aligned. Where more
# than 16 external interrupts are used, the offset word alignment must be
# increased to accommodate vectors for all the exceptions and interrupts
# supported and keep the required table size naturally aligned."

# For reference on the max number in interrupts per processor look in The
# technical reference manual "Interrupt Controller Type Register, ICTR" section.
# * For M23 & M33: Maximum of 480 exception (480 * 4 bytes ~= 0x800).
# * For M4, M4F, M3 & M7: Maximum of 256 exceptions (256*4 bytes == 0x400).
# * For M0, M0+ & M1: Maximum of 48 exceptions (48*4 bytes = 192 bytes ~= 0x100).

# The values defined here are a theoretical maximum, in practice most cpu's
# CPU_IRQ_NUMOF value is around 100, in these cases the value can be reduced
# accordingly in the cpu Makefile.include, e.g: `kinetis/Makefile.include`
ifneq (,$(filter cortex-m23% cortex-m33%,$(CPU_CORE)))
  RIOTBOOT_HDR_LEN ?= 0x800
else ifneq (,$(filter cortex-m3% cortex-m4% cortex-m7%,$(CPU_CORE)))
  RIOTBOOT_HDR_LEN ?= 0x400
else
  RIOTBOOT_HDR_LEN ?= 0x100
endif

# Configure riotboot bootloader and slot lengths
# 4KB are currently enough, set it to 16KB if USB-DFU or tinyUSB DFU is used
ifneq (,$(filter usbus_dfu tinyusb_dfu,$(USEMODULE)))
  RIOTBOOT_LEN ?= 0x4000
else
  RIOTBOOT_LEN ?= 0x1000
endif

# JLink is able to flash any ARM CPUs
PROGRAMMERS_SUPPORTED += jlink