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Elixir Cross Referencer

# Kconfig - Atmel SAM3 family processor configuration options

#
# Copyright (c) 2016 Intel Corporation.
# Copyright (c) 2014-2015 Wind River Systems, Inc.
#
# SPDX-License-Identifier: Apache-2.0
#

config SOC_ATMEL_SAM3
	bool
	depends on ARM
	default n

if ARM && SOC_ATMEL_SAM3

config SOC_ATMEL_SAM3_EXT_SLCK
	bool "Atmel SAM3 to use external crystal oscillator for slow clock"
	default n
	help
	Says y if you want to use external 32 kHz crystal
	oscillator to drive the slow clock. Note that this
	adds a few seconds to boot time, as the crystal
	needs to stabilize after power-up.

	Says n if you do not need accraute and precise timers.
	The slow clock will be driven by the internal fast
	RC oscillator running at 32 kHz.

config SOC_ATMEL_SAM3_EXT_MAINCK
	bool "Atmel SAM3 to use external crystal oscillator for main clock"
	default n
	help
	The main clock is being used to drive the PLL, and
	thus driving the processor clock.

	Says y if you want to use external crystal oscillator
	to drive the main clock. Note that this adds about
	a second to boot time, as the crystal needs to
	stabilize after power-up.

	The crystal used here can be from 3 to 20 MHz.

	Says n here will use the internal fast RC oscillator
	running at 12 MHz.

config SOC_ATMEL_SAM3_PLLA_MULA
	hex
	default 0x06
	help
	This is the multiplier (MULA) used by the PLL.
	The processor clock is (MAINCK * (MULA + 1) / DIVA).

	Board config file can override this settings
	for a particular board.

	With default of MULA == 6, and DIVA == 1,
	PLL is running at 7 times of main clock.

config SOC_ATMEL_SAM3_PLLA_DIVA
	hex
	default 0x01
	help
	This is the divider (DIVA) used by the PLL.
	The processor clock is (MAINCK * (MULA + 1) / DIVA).

	Board config file can override this settings
	for a particular board.

	With default of MULA == 6, and DIVA == 1,
	PLL is running at 7 times of main clock.

config SOC_ATMEL_SAM3_WAIT_MODE
	bool "Atmel SAM3 goes to Wait mode instead of Sleep mode"
	depends on SOC_ATMEL_SAM3_EXT_MAINCK
	default y if DEBUG
	help
	For JTAG debugging CPU clock (HCLK) should not stop. In order
	to achieve this, make CPU go to Wait mode instead of Sleep
	mode while using external crystal oscillator for main clock.

endif # SOC_ATMEL_SAM3