electronics
/
libopencm3
9
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

stm32l4: rcc: MSI range handling

This commit is contained in:
Karl Palsson 2016-03-12 22:16:09 +00:00
parent 97d644c4d3
commit c5b00c3dda
2 changed files with 47 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
include/libopencm3/stm32/l4/rcc.h
View File

@ -115,6 +115,18 @@ Twelve frequency ranges are available: 100 kHz, 200 kHz, 400 kHz, 800 kHz,
@{*/
#define RCC_CR_MSIRANGE_SHIFT 4
#define RCC_CR_MSIRANGE_MASK 0xf
#define RCC_CR_MSIRANGE_100KHZ 0
#define RCC_CR_MSIRANGE_200KHZ 1
#define RCC_CR_MSIRANGE_400KHZ 2
#define RCC_CR_MSIRANGE_800KHZ 3
#define RCC_CR_MSIRANGE_1MHZ 4
#define RCC_CR_MSIRANGE_2MHZ 5
#define RCC_CR_MSIRANGE_4MHZ 6
#define RCC_CR_MSIRANGE_8MHZ 7
#define RCC_CR_MSIRANGE_16MHZ 8
#define RCC_CR_MSIRANGE_24MHZ 9
#define RCC_CR_MSIRANGE_32MHZ 10
#define RCC_CR_MSIRANGE_48MHZ 11
/*@}*/
#define RCC_CR_MSIRGSEL (1 << 3)
#define RCC_CR_MSIPLLEN (1 << 2)
@ -674,6 +686,10 @@ Twelve frequency ranges are available: 100 kHz, 200 kHz, 400 kHz, 800 kHz,
@{*/
#define RCC_CSR_MSIRANGE_MASK 0xf
#define RCC_CSR_MSIRANGE_SHIFT 8
#define RCC_CSR_MSIRANGE_1MHZ 4
#define RCC_CSR_MSIRANGE_2MHZ 5
#define RCC_CSR_MSIRANGE_4MHZ 6
#define RCC_CSR_MSIRANGE_8MHZ 7
/*@}*/
#define RCC_CSR_LSIRDY (1 << 1)
@ -930,6 +946,8 @@ void rcc_set_ppre1(uint32_t ppre1);
void rcc_set_hpre(uint32_t hpre);
void rcc_set_main_pll(uint32_t source, uint32_t pllm, uint32_t plln, uint32_t pllp, uint32_t pllq, uint32_t pllr);
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);
END_DECLS

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

@ -356,4 +356,33 @@ uint32_t rcc_system_clock_source(void)
return ((RCC_CFGR >> RCC_CFGR_SWS_SHIFT) & RCC_CFGR_SWS_MASK);
}
/**
* Set the msi run time range.
* Can only be called when MSI is either OFF, or when MSI is on _and_
* ready. (RCC_CR_MSIRDY bit). @sa rcc_set_msi_range_standby
* @param msi_range range number @ref rcc_cr_msirange
*/
void rcc_set_msi_range(uint32_t msi_range)
{
uint32_t reg = RCC_CR;
reg &= ~(RCC_CR_MSIRANGE_MASK << RCC_CR_MSIRANGE_SHIFT);
reg |= msi_range << RCC_CR_MSIRANGE_SHIFT;
RCC_CR = reg | RCC_CR_MSIRGSEL;
}
/**
* Set the msi range after reset/standby.
* Until MSIRGSEl bit is set, this defines the MSI range.
* Note that not all MSI range values are allowed here!
* @sa rcc_set_msi_range
* @param msi_range range number valid for post standby @ref rcc_csr_msirange
*/
void rcc_set_msi_range_standby(uint32_t msi_range)
{
uint32_t reg = RCC_CSR;
reg &= ~(RCC_CSR_MSIRANGE_MASK << RCC_CSR_MSIRANGE_SHIFT);
reg |= msi_range << RCC_CSR_MSIRANGE_SHIFT;
RCC_CSR = reg;
}
/**@}*/