/* IRQ handler to handle updates to the HCLK frequency.
* This updates the SysTick scales. */
static void stm32_rcc_hclk_upd_irq_handler(void *opaque, int n, int level)
{
Stm32Rcc *s = (Stm32Rcc *)opaque;
uint32_t hclk_freq, ext_ref_freq;
hclk_freq = clktree_get_output_freq(s->HCLK);
/* Only update the scales if the frequency is not zero. */
if(hclk_freq > 0) {
ext_ref_freq = hclk_freq / 8;
/* Update the scales - these are the ratio of QEMU clock ticks
* (which is an unchanging number independent of the CPU frequency) to
* system/external clock ticks.
*/
system_clock_scale = get_ticks_per_sec() / hclk_freq;
external_ref_clock_scale = get_ticks_per_sec() / ext_ref_freq;
}
#ifdef DEBUG_STM32_RCC
DPRINTF("Cortex SYSTICK frequency set to %lu Hz (scale set to %d).\n",
(unsigned long)hclk_freq, system_clock_scale);
DPRINTF("Cortex SYSTICK ext ref frequency set to %lu Hz "
"(scale set to %d).\n",
(unsigned long)ext_ref_freq, external_ref_clock_scale);
#endif
}
uint32_t stm32_rcc_get_periph_freq(
Stm32Rcc *s,
stm32_periph_t periph)
{
Clk clk;
clk = s->PERIPHCLK[periph];
assert(clk != NULL);
return clktree_get_output_freq(clk);
}
