ChibiOS Free Embedded RTOS

I have a question about systick timer load value calculation.
You can see at STM32F4 reference manual(RM0090) clock scheme (5.2, fig.9), that Cortex system timer frequency is equal HCLK frequency divided by 8.
Therefore I think, systick load value should be calculated as HCLK / (8 * CH_FREQUENCY).
But if you see ChibiOS-RT code (e.g. version 2.6.6), it calculated as STM32_HCLK / CH_FREQUENCY.
What is the reason?

Hi,

The Cortex-M can feed the systick from the system clock or from an external signal, that external signal is that /8 line. ChibiOS uses the system clock direct feed because it is platform independent.

Giovanni