diff options
Diffstat (limited to 'libmaple/stm32f2/rcc.c')
-rw-r--r-- | libmaple/stm32f2/rcc.c | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/libmaple/stm32f2/rcc.c b/libmaple/stm32f2/rcc.c index 7bc220d..b94f2e6 100644 --- a/libmaple/stm32f2/rcc.c +++ b/libmaple/stm32f2/rcc.c @@ -160,3 +160,37 @@ void rcc_set_prescaler(rcc_prescaler prescaler, uint32 divider) { }; rcc_do_set_prescaler(masks, prescaler, divider); } + +/** + * @brief Configure the main PLL. + * + * You may only call this function while the PLL is disabled. + * + * @param pll_cfg Desired PLL configuration. The data field must point + * to a valid struct stm32f2_rcc_pll_data. + */ +void rcc_configure_pll(rcc_pll_cfg *pll_cfg) { + stm32f2_rcc_pll_data *data = pll_cfg->data; + uint32 pllcfgr; + + /* Sanity-check all the parameters */ + ASSERT_FAULT((data->pllq >= 4) && (data->pllq <= 15)); + ASSERT_FAULT((data->pllp >= 2) && (data->pllp <= 8)); + ASSERT_FAULT(!(data->pllp & 1)); + ASSERT_FAULT((data->plln >= 192) && (data->plln <= 432)); + ASSERT_FAULT((data->pllm >= 2) && (data->pllm <= 63)); + + /* Update RCC_PLLCFGR to reflect new values. */ + pllcfgr = RCC_BASE->PLLCFGR; + pllcfgr &= ~(RCC_PLLCFGR_PLLQ | + RCC_PLLCFGR_PLLP | + RCC_PLLCFGR_PLLN | + RCC_PLLCFGR_PLLM | + RCC_PLLCFGR_PLLSRC); + pllcfgr |= (pll_cfg->pllsrc | + (data->pllq << 24) | + (((data->pllp >> 1) - 1) << 16) | + (data->plln << 6) | + data->pllm); + RCC_BASE->PLLCFGR = pllcfgr; +} |