jackcartersmith/blackmagic
1
0
Fork 0
Code Issues Pull Requests Releases Activity

stm32:l4: rcc: Add helper functions

Browse Source 
Add functions for PLL output and 48MHz clock source selection
This commit is contained in:
Bruno Randolf 2017-12-28 13:32:29 +00:00 committed by Karl Palsson
parent a1ffdc59f0
commit fe722d4643
2 changed files with 31 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
include/libopencm3/stm32/l4/rcc.h
View File

@ -962,6 +962,8 @@ void rcc_set_main_pll(uint32_t source, uint32_t pllm, uint32_t plln, uint32_t pl
uint32_t rcc_system_clock_source(void);
void rcc_set_msi_range(uint32_t msi_range);
void rcc_set_msi_range_standby(uint32_t msi_range);
void rcc_pll_output_enable(uint32_t pllout);
void rcc_set_clock48_source(uint32_t clksel);
END_DECLS

29
lib/stm32/l4/rcc.c
View File

@ -369,4 +369,33 @@ void rcc_set_msi_range_standby(uint32_t msi_range)
RCC_CSR = reg;
}
/** Enable PLL Output
*
* - P (RCC_PLLCFGR_PLLPEN)
* - Q (RCC_PLLCFGR_PLLQEN)
* - R (RCC_PLLCFGR_PLLREN)
*
* @param pllout One or more of the definitions above
*/
void rcc_pll_output_enable(uint32_t pllout)
{
RCC_PLLCFGR |= pllout;
}
/** Set clock source for 48MHz clock
*
* The 48 MHz clock is derived from one of the four following sources:
* - main PLL VCO (RCC_CCIPR_CLK48SEL_PLL)
* - PLLSAI1 VCO (RCC_CCIPR_CLK48SEL_PLLSAI1Q)
* - MSI clock (RCC_CCIPR_CLK48SEL_MSI)
* - HSI48 internal oscillator (RCC_CCIPR_CLK48SEL_HSI48)
*
* @param clksel One of the definitions above
*/
void rcc_set_clock48_source(uint32_t clksel)
{
RCC_CCIPR &= ~(RCC_CCIPR_CLK48SEL_MASK << RCC_CCIPR_CLK48SEL_SHIFT);
RCC_CCIPR |= (clksel << RCC_CCIPR_CLK48SEL_SHIFT);
}
/**@}*/