Split out mcu_selection to platform (#19701)

platforms/avr/mcu_selection.mk

@@ -0,0 +1,95 @@
+ifneq (,$(filter $(MCU),at90usb162 atmega16u2 atmega32u2 atmega16u4 atmega32u4 at90usb646 at90usb647 at90usb1286 at90usb1287))
+  PROTOCOL = LUFA
+
+  # Processor frequency.
+  #     This will define a symbol, F_CPU, in all source code files equal to the
+  #     processor frequency in Hz. You can then use this symbol in your source code to
+  #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
+  #     automatically to create a 32-bit value in your source code.
+  #
+  #     This will be an integer division of F_USB below, as it is sourced by
+  #     F_USB after it has run through any CPU prescalers. Note that this value
+  #     does not *change* the processor frequency - it should merely be updated to
+  #     reflect the processor speed set externally so that the code can use accurate
+  #     software delays.
+  F_CPU ?= 16000000
+
+  # LUFA specific
+  #
+  # Target architecture (see library "Board Types" documentation).
+  ARCH = AVR8
+
+  # Input clock frequency.
+  #     This will define a symbol, F_USB, in all source code files equal to the
+  #     input clock frequency (before any prescaling is performed) in Hz. This value may
+  #     differ from F_CPU if prescaling is used on the latter, and is required as the
+  #     raw input clock is fed directly to the PLL sections of the AVR for high speed
+  #     clock generation for the USB and other AVR subsections. Do NOT tack on a 'UL'
+  #     at the end, this will be done automatically to create a 32-bit value in your
+  #     source code.
+  #
+  #     If no clock division is performed on the input clock inside the AVR (via the
+  #     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
+  F_USB ?= $(F_CPU)
+
+  # Interrupt driven control endpoint task
+  ifeq (,$(filter $(NO_INTERRUPT_CONTROL_ENDPOINT),yes))
+    OPT_DEFS += -DINTERRUPT_CONTROL_ENDPOINT
+  endif
+  ifneq (,$(filter $(MCU),at90usb162 atmega16u2 atmega32u2))
+    NO_I2C = yes
+  endif
+endif
+
+ifneq (,$(filter $(MCU),atmega32a))
+  # MCU name for avrdude
+  AVRDUDE_MCU = m32
+
+  PROTOCOL = VUSB
+
+  # Processor frequency.
+  #     This will define a symbol, F_CPU, in all source code files equal to the
+  #     processor frequency in Hz. You can then use this symbol in your source code to
+  #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
+  #     automatically to create a 32-bit value in your source code.
+  F_CPU ?= 12000000
+endif
+
+ifneq (,$(filter $(MCU),atmega328p))
+  # MCU name for avrdude
+  AVRDUDE_MCU = m328p
+
+  PROTOCOL = VUSB
+
+  # Processor frequency.
+  #     This will define a symbol, F_CPU, in all source code files equal to the
+  #     processor frequency in Hz. You can then use this symbol in your source code to
+  #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
+  #     automatically to create a 32-bit value in your source code.
+  F_CPU ?= 16000000
+endif
+
+ifneq (,$(filter $(MCU),atmega328))
+  # MCU name for avrdude
+  AVRDUDE_MCU = m328
+
+  PROTOCOL = VUSB
+
+  # Processor frequency.
+  #     This will define a symbol, F_CPU, in all source code files equal to the
+  #     processor frequency in Hz. You can then use this symbol in your source code to
+  #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
+  #     automatically to create a 32-bit value in your source code.
+  F_CPU ?= 16000000
+endif
+
+ifneq (,$(filter $(MCU),attiny85))
+  PROTOCOL = VUSB
+
+  # Processor frequency.
+  #     This will define a symbol, F_CPU, in all source code files equal to the
+  #     processor frequency in Hz. You can then use this symbol in your source code to
+  #     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
+  #     automatically to create a 32-bit value in your source code.
+  F_CPU ?= 16500000
+endif