stm32: Optimize stm32f401 peripheral clock

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
This commit is contained in:
Kevin O'Connor 2021-02-19 12:19:32 -05:00
parent 90ffa0685f
commit 267a2f3a38
1 changed files with 6 additions and 2 deletions

View File

@ -12,7 +12,8 @@
#include "internal.h" // enable_pclock #include "internal.h" // enable_pclock
#include "sched.h" // sched_main #include "sched.h" // sched_main
#define FREQ_PERIPH (CONFIG_CLOCK_FREQ / 4) #define FREQ_PERIPH_DIV (CONFIG_MACH_STM32F401 ? 2 : 4)
#define FREQ_PERIPH (CONFIG_CLOCK_FREQ / FREQ_PERIPH_DIV)
#define FREQ_USB 48000000 #define FREQ_USB 48000000
// Enable a peripheral clock // Enable a peripheral clock
@ -236,7 +237,10 @@ clock_setup(void)
; ;
// Switch system clock to PLL // Switch system clock to PLL
RCC->CFGR = RCC_CFGR_PPRE1_DIV4 | RCC_CFGR_PPRE2_DIV4 | RCC_CFGR_SW_PLL; if (FREQ_PERIPH_DIV == 2)
RCC->CFGR = RCC_CFGR_PPRE1_DIV2 | RCC_CFGR_PPRE2_DIV2 | RCC_CFGR_SW_PLL;
else
RCC->CFGR = RCC_CFGR_PPRE1_DIV4 | RCC_CFGR_PPRE2_DIV4 | RCC_CFGR_SW_PLL;
while ((RCC->CFGR & RCC_CFGR_SWS_Msk) != RCC_CFGR_SWS_PLL) while ((RCC->CFGR & RCC_CFGR_SWS_Msk) != RCC_CFGR_SWS_PLL)
; ;
} }