Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/stm32/stm32f1/STM32F101/I2C1/CCR#0x0
Clock control register
Clock control register in Fast/Standard mode (Master mode)
Fast mode duty cycle
I2C master mode selection
https://github.com/modm-io/cmsis-svd-stm32