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| author | Kevin O'Connor <kevin@koconnor.net> | 2021-02-19 12:19:32 -0500 |
|---|---|---|
| committer | Kevin O'Connor <kevin@koconnor.net> | 2021-02-19 12:19:32 -0500 |
| commit | 267a2f3a38cafd1949a9e276b7020030e9c9c0a4 (patch) | |
| tree | ca4643aafc5e2c7b517f71216baa7aa3ee026728 | |
| parent | 90ffa0685f368d00a76f9b7746315aa3b3a5f1ec (diff) | |
| download | kutter-267a2f3a38cafd1949a9e276b7020030e9c9c0a4.tar.gz kutter-267a2f3a38cafd1949a9e276b7020030e9c9c0a4.tar.xz kutter-267a2f3a38cafd1949a9e276b7020030e9c9c0a4.zip | |
stm32: Optimize stm32f401 peripheral clock
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
| -rw-r--r-- | src/stm32/stm32f4.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/src/stm32/stm32f4.c b/src/stm32/stm32f4.c index dc7a15aa..4bab40bc 100644 --- a/src/stm32/stm32f4.c +++ b/src/stm32/stm32f4.c @@ -12,7 +12,8 @@ #include "internal.h" // enable_pclock #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 // Enable a peripheral clock @@ -236,7 +237,10 @@ clock_setup(void) ; // 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) ; } |