embassy/embassy-stm32/src/rcc/l4.rs
2022-07-10 20:59:36 +03:00

502 lines
13 KiB
Rust

use crate::pac::rcc::vals::{Hpre, Msirange, Pllsrc, Ppre, Sw};
use crate::pac::{FLASH, RCC};
use crate::rcc::{set_freqs, Clocks};
use crate::time::{Hertz, U32Ext};
/// HSI speed
pub const HSI_FREQ: Hertz = Hertz(16_000_000);
/// LSI speed
pub const LSI_FREQ: Hertz = Hertz(32_000);
/// System clock mux source
#[derive(Clone, Copy)]
pub enum ClockSrc {
MSI(MSIRange),
PLL(PLLSource, PLLClkDiv, PLLSrcDiv, PLLMul, Option<PLL48Div>),
HSE(Hertz),
HSI16,
}
/// MSI Clock Range
///
/// These ranges control the frequency of the MSI. Internally, these ranges map
/// to the `MSIRANGE` bits in the `RCC_ICSCR` register.
#[derive(Clone, Copy)]
pub enum MSIRange {
/// Around 100 kHz
Range0,
/// Around 200 kHz
Range1,
/// Around 400 kHz
Range2,
/// Around 800 kHz
Range3,
/// Around 1 MHz
Range4,
/// Around 2 MHz
Range5,
/// Around 4 MHz (reset value)
Range6,
/// Around 8 MHz
Range7,
/// Around 16 MHz
Range8,
/// Around 24 MHz
Range9,
/// Around 32 MHz
Range10,
/// Around 48 MHz
Range11,
}
impl Default for MSIRange {
fn default() -> MSIRange {
MSIRange::Range6
}
}
pub type PLL48Div = PLLClkDiv;
pub type PLLSAI1RDiv = PLLClkDiv;
pub type PLLSAI1QDiv = PLLClkDiv;
pub type PLLSAI1PDiv = PLLClkDiv;
/// PLL divider
#[derive(Clone, Copy)]
pub enum PLLDiv {
Div2,
Div3,
Div4,
}
/// AHB prescaler
#[derive(Clone, Copy, PartialEq)]
pub enum AHBPrescaler {
NotDivided,
Div2,
Div4,
Div8,
Div16,
Div64,
Div128,
Div256,
Div512,
}
/// APB prescaler
#[derive(Clone, Copy)]
pub enum APBPrescaler {
NotDivided,
Div2,
Div4,
Div8,
Div16,
}
/// PLL clock input source
#[derive(Clone, Copy)]
pub enum PLLSource {
HSI16,
HSE(Hertz),
MSI(MSIRange),
}
seq_macro::seq!(N in 8..=86 {
#[derive(Clone, Copy)]
pub enum PLLMul {
#(
Mul~N,
)*
}
impl From<PLLMul> for u8 {
fn from(val: PLLMul) -> u8 {
match val {
#(
PLLMul::Mul~N => N,
)*
}
}
}
impl PLLMul {
pub fn to_mul(self) -> u32 {
match self {
#(
PLLMul::Mul~N => N,
)*
}
}
}
});
#[derive(Clone, Copy)]
pub enum PLLClkDiv {
Div2,
Div4,
Div6,
Div8,
}
impl PLLClkDiv {
pub fn to_div(self) -> u32 {
let val: u8 = self.into();
(val as u32 + 1) * 2
}
}
impl From<PLLClkDiv> for u8 {
fn from(val: PLLClkDiv) -> u8 {
match val {
PLLClkDiv::Div2 => 0b00,
PLLClkDiv::Div4 => 0b01,
PLLClkDiv::Div6 => 0b10,
PLLClkDiv::Div8 => 0b11,
}
}
}
#[derive(Clone, Copy)]
pub enum PLLSrcDiv {
Div1,
Div2,
Div3,
Div4,
Div5,
Div6,
Div7,
Div8,
}
impl PLLSrcDiv {
pub fn to_div(self) -> u32 {
let val: u8 = self.into();
val as u32 + 1
}
}
impl From<PLLSrcDiv> for u8 {
fn from(val: PLLSrcDiv) -> u8 {
match val {
PLLSrcDiv::Div1 => 0b000,
PLLSrcDiv::Div2 => 0b001,
PLLSrcDiv::Div3 => 0b010,
PLLSrcDiv::Div4 => 0b011,
PLLSrcDiv::Div5 => 0b100,
PLLSrcDiv::Div6 => 0b101,
PLLSrcDiv::Div7 => 0b110,
PLLSrcDiv::Div8 => 0b111,
}
}
}
impl From<PLLSource> for Pllsrc {
fn from(val: PLLSource) -> Pllsrc {
match val {
PLLSource::HSI16 => Pllsrc::HSI16,
PLLSource::HSE(_) => Pllsrc::HSE,
PLLSource::MSI(_) => Pllsrc::MSI,
}
}
}
impl From<APBPrescaler> for Ppre {
fn from(val: APBPrescaler) -> Ppre {
match val {
APBPrescaler::NotDivided => Ppre::DIV1,
APBPrescaler::Div2 => Ppre::DIV2,
APBPrescaler::Div4 => Ppre::DIV4,
APBPrescaler::Div8 => Ppre::DIV8,
APBPrescaler::Div16 => Ppre::DIV16,
}
}
}
impl From<AHBPrescaler> for Hpre {
fn from(val: AHBPrescaler) -> Hpre {
match val {
AHBPrescaler::NotDivided => Hpre::DIV1,
AHBPrescaler::Div2 => Hpre::DIV2,
AHBPrescaler::Div4 => Hpre::DIV4,
AHBPrescaler::Div8 => Hpre::DIV8,
AHBPrescaler::Div16 => Hpre::DIV16,
AHBPrescaler::Div64 => Hpre::DIV64,
AHBPrescaler::Div128 => Hpre::DIV128,
AHBPrescaler::Div256 => Hpre::DIV256,
AHBPrescaler::Div512 => Hpre::DIV512,
}
}
}
impl From<MSIRange> for Msirange {
fn from(val: MSIRange) -> Msirange {
match val {
MSIRange::Range0 => Msirange::RANGE100K,
MSIRange::Range1 => Msirange::RANGE200K,
MSIRange::Range2 => Msirange::RANGE400K,
MSIRange::Range3 => Msirange::RANGE800K,
MSIRange::Range4 => Msirange::RANGE1M,
MSIRange::Range5 => Msirange::RANGE2M,
MSIRange::Range6 => Msirange::RANGE4M,
MSIRange::Range7 => Msirange::RANGE8M,
MSIRange::Range8 => Msirange::RANGE16M,
MSIRange::Range9 => Msirange::RANGE24M,
MSIRange::Range10 => Msirange::RANGE32M,
MSIRange::Range11 => Msirange::RANGE48M,
}
}
}
impl From<MSIRange> for u32 {
fn from(val: MSIRange) -> u32 {
match val {
MSIRange::Range0 => 100_000,
MSIRange::Range1 => 200_000,
MSIRange::Range2 => 400_000,
MSIRange::Range3 => 800_000,
MSIRange::Range4 => 1_000_000,
MSIRange::Range5 => 2_000_000,
MSIRange::Range6 => 4_000_000,
MSIRange::Range7 => 8_000_000,
MSIRange::Range8 => 16_000_000,
MSIRange::Range9 => 24_000_000,
MSIRange::Range10 => 32_000_000,
MSIRange::Range11 => 48_000_000,
}
}
}
/// Clocks configutation
pub struct Config {
pub mux: ClockSrc,
pub ahb_pre: AHBPrescaler,
pub apb1_pre: APBPrescaler,
pub apb2_pre: APBPrescaler,
pub pllsai1: Option<(
PLLMul,
PLLSrcDiv,
Option<PLLSAI1RDiv>,
Option<PLLSAI1QDiv>,
Option<PLLSAI1PDiv>,
)>,
#[cfg(not(any(stm32l471, stm32l475, stm32l476, stm32l486)))]
pub hsi48: bool,
}
impl Default for Config {
#[inline]
fn default() -> Config {
Config {
mux: ClockSrc::MSI(MSIRange::Range6),
ahb_pre: AHBPrescaler::NotDivided,
apb1_pre: APBPrescaler::NotDivided,
apb2_pre: APBPrescaler::NotDivided,
pllsai1: None,
#[cfg(not(any(stm32l471, stm32l475, stm32l476, stm32l486)))]
hsi48: false,
}
}
}
pub(crate) unsafe fn init(config: Config) {
let (sys_clk, sw) = match config.mux {
ClockSrc::MSI(range) => {
// Enable MSI
RCC.cr().write(|w| {
let bits: Msirange = range.into();
w.set_msirange(bits);
w.set_msipllen(false);
w.set_msirgsel(true);
w.set_msion(true);
});
while !RCC.cr().read().msirdy() {}
// Enable as clock source for USB, RNG if running at 48 MHz
if let MSIRange::Range11 = range {
RCC.ccipr().modify(|w| {
w.set_clk48sel(0b11);
});
}
(range.into(), Sw::MSI)
}
ClockSrc::HSI16 => {
// Enable HSI16
RCC.cr().write(|w| w.set_hsion(true));
while !RCC.cr().read().hsirdy() {}
(HSI_FREQ.0, Sw::HSI16)
}
ClockSrc::HSE(freq) => {
// Enable HSE
RCC.cr().write(|w| w.set_hseon(true));
while !RCC.cr().read().hserdy() {}
(freq.0, Sw::HSE)
}
ClockSrc::PLL(src, div, prediv, mul, pll48div) => {
let src_freq = match src {
PLLSource::HSE(freq) => {
// Enable HSE
RCC.cr().write(|w| w.set_hseon(true));
while !RCC.cr().read().hserdy() {}
freq.0
}
PLLSource::HSI16 => {
// Enable HSI
RCC.cr().write(|w| w.set_hsion(true));
while !RCC.cr().read().hsirdy() {}
HSI_FREQ.0
}
PLLSource::MSI(range) => {
// Enable MSI
RCC.cr().write(|w| {
let bits: Msirange = range.into();
w.set_msirange(bits);
w.set_msipllen(false); // should be turned on if LSE is started
w.set_msirgsel(true);
w.set_msion(true);
});
while !RCC.cr().read().msirdy() {}
range.into()
}
};
// Disable PLL
RCC.cr().modify(|w| w.set_pllon(false));
while RCC.cr().read().pllrdy() {}
let freq = (src_freq / prediv.to_div() * mul.to_mul()) / div.to_div();
#[cfg(any(stm32l4px, stm32l4qx, stm32l4rx, stm32l4sx))]
assert!(freq <= 120_000_000);
#[cfg(not(any(stm32l4px, stm32l4qx, stm32l4rx, stm32l4sx)))]
assert!(freq <= 80_000_000);
RCC.pllcfgr().write(move |w| {
w.set_plln(mul.into());
w.set_pllm(prediv.into());
w.set_pllr(div.into());
if let Some(pll48div) = pll48div {
w.set_pllq(pll48div.into());
w.set_pllqen(true);
}
w.set_pllsrc(src.into());
});
// Enable as clock source for USB, RNG if PLL48 divisor is provided
if let Some(pll48div) = pll48div {
let freq = (src_freq / prediv.to_div() * mul.to_mul()) / pll48div.to_div();
assert!(freq == 48_000_000);
RCC.ccipr().modify(|w| {
w.set_clk48sel(0b10);
});
}
if let Some((mul, prediv, r_div, q_div, p_div)) = config.pllsai1 {
RCC.pllsai1cfgr().write(move |w| {
w.set_pllsai1n(mul.into());
w.set_pllsai1m(prediv.into());
if let Some(r_div) = r_div {
w.set_pllsai1r(r_div.into());
w.set_pllsai1ren(true);
}
if let Some(q_div) = q_div {
w.set_pllsai1q(q_div.into());
w.set_pllsai1qen(true);
let freq = (src_freq / prediv.to_div() * mul.to_mul()) / q_div.to_div();
if freq == 48_000_000 {
RCC.ccipr().modify(|w| {
w.set_clk48sel(0b1);
});
}
}
if let Some(p_div) = p_div {
w.set_pllsai1pdiv(p_div.into());
w.set_pllsai1pen(true);
}
});
RCC.cr().modify(|w| w.set_pllsai1on(true));
}
// Enable PLL
RCC.cr().modify(|w| w.set_pllon(true));
while !RCC.cr().read().pllrdy() {}
RCC.pllcfgr().modify(|w| w.set_pllren(true));
(freq, Sw::PLL)
}
};
#[cfg(not(any(stm32l471, stm32l475, stm32l476, stm32l486)))]
if config.hsi48 {
RCC.crrcr().modify(|w| w.set_hsi48on(true));
while !RCC.crrcr().read().hsi48rdy() {}
// Enable as clock source for USB, RNG and SDMMC
RCC.ccipr().modify(|w| w.set_clk48sel(0));
}
// Set flash wait states
FLASH.acr().modify(|w| {
w.set_latency(if sys_clk <= 16_000_000 {
0b000
} else if sys_clk <= 32_000_000 {
0b001
} else if sys_clk <= 48_000_000 {
0b010
} else if sys_clk <= 64_000_000 {
0b011
} else {
0b100
});
});
RCC.cfgr().modify(|w| {
w.set_sw(sw);
w.set_hpre(config.ahb_pre.into());
w.set_ppre1(config.apb1_pre.into());
w.set_ppre2(config.apb2_pre.into());
});
let ahb_freq: u32 = match config.ahb_pre {
AHBPrescaler::NotDivided => sys_clk,
pre => {
let pre: Hpre = pre.into();
let pre = 1 << (pre.0 as u32 - 7);
sys_clk / pre
}
};
let (apb1_freq, apb1_tim_freq) = match config.apb1_pre {
APBPrescaler::NotDivided => (ahb_freq, ahb_freq),
pre => {
let pre: Ppre = pre.into();
let pre: u8 = 1 << (pre.0 - 3);
let freq = ahb_freq / pre as u32;
(freq, freq * 2)
}
};
let (apb2_freq, apb2_tim_freq) = match config.apb2_pre {
APBPrescaler::NotDivided => (ahb_freq, ahb_freq),
pre => {
let pre: Ppre = pre.into();
let pre: u8 = 1 << (pre.0 - 3);
let freq = ahb_freq / (1 << (pre as u8 - 3));
(freq, freq * 2)
}
};
set_freqs(Clocks {
sys: sys_clk.hz(),
ahb1: ahb_freq.hz(),
ahb2: ahb_freq.hz(),
ahb3: ahb_freq.hz(),
apb1: apb1_freq.hz(),
apb2: apb2_freq.hz(),
apb1_tim: apb1_tim_freq.hz(),
apb2_tim: apb2_tim_freq.hz(),
});
}