Add support for use of HSE (incorrectly named PREDIV1)as input of PLL,
along with HSE bypass for stabilized external clock, and XTPRE
prescaler. Update PLL handling so that we do not unnecessarily enable
PLL clocks, instead enabling only the clocks sources that are required
as per user's configuration.
This change allows higher SYSCLK clock values, up to 72MHz.
Change-Id: Ia7c2be3ce11ac0de2efa664b20e7ab5fddd57a51
Origin: Original
Signed-off-by: Maciej Borzecki <maciek.borzecki@gmail.com>
The patch adds a driver for STM32F10x series RCC (Reset and Clock
Control) subsystem.
The module is primarily responsible for setting up of MCU's clock
tree. In particular the driver sets up SYSCLK, PLL (with source
configuration), AHB prescaler, and APB1/APB2 prescalers. As part of this
functionality, the subsystem can enable/disable clock signal for
particular peripherals, thus reducing the power consumption of the MCU.
The driver implements clock control driver API. However, subsystem IDs
being HW specific are exposed in driver public header that must be
included by callers. The driver registers a single device using a common
name STM32_CLOCK_CONTROL_NAME. The device is initialized at
the PRIMARY level with priority 1. This allows the initialization to
take place right after SoC initialization routine.
The driver depends on selection of SOC_STM32F1X config option and is MCU
specific.
Change-Id: I8bea5db20726a24bce7b7ffe0b95de543240429a
Origin: Original
Signed-off-by: Maciej Borzecki <maciek.borzecki@gmail.com>