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Use found divider instead of re-reading brr

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Rasmus Melchior Jacobsen 2023-05-26 23:48:49 +02:00
parent f616b22159
commit cb5df138d6
1 changed files with 7 additions and 7 deletions
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14
embassy-stm32/src/usart/mod.rs
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@ -836,7 +836,7 @@ fn configure(r: Regs, config: &Config, pclk_freq: Hertz, kind: Kind, enable_rx:
#[cfg(not(usart_v1))] #[cfg(not(usart_v1))]
let mut over8 = false; let mut over8 = false;
let mut found = false; let mut found = None;
for &(presc, _presc_val) in &DIVS { for &(presc, _presc_val) in &DIVS {
let denom = (config.baudrate * presc as u32) as u64; let denom = (config.baudrate * presc as u32) as u64;
let div = (pclk_freq.0 as u64 * mul + (denom / 2)) / denom; let div = (pclk_freq.0 as u64 * mul + (denom / 2)) / denom;
@ -858,26 +858,26 @@ fn configure(r: Regs, config: &Config, pclk_freq: Hertz, kind: Kind, enable_rx:
#[cfg(usart_v4)] #[cfg(usart_v4)]
r.presc().write(|w| w.set_prescaler(_presc_val)); r.presc().write(|w| w.set_prescaler(_presc_val));
} }
found = true; found = Some(div);
break; break;
} }
panic!("USART: baudrate too high"); panic!("USART: baudrate too high");
} }
if div < brr_max { if div < brr_max {
let div = div as u32;
unsafe { unsafe {
r.brr().write_value(regs::Brr(div as u32)); r.brr().write_value(regs::Brr(div));
#[cfg(usart_v4)] #[cfg(usart_v4)]
r.presc().write(|w| w.set_prescaler(_presc_val)); r.presc().write(|w| w.set_prescaler(_presc_val));
} }
found = true; found = Some(div);
break; break;
} }
} }
assert!(found, "USART: baudrate too low"); let div = found.expect("USART: baudrate too low");
let brr = unsafe { r.brr().read().brr() as u32 };
#[cfg(not(usart_v1))] #[cfg(not(usart_v1))]
let oversampling = if over8 { "8 bit" } else { "16 bit" }; let oversampling = if over8 { "8 bit" } else { "16 bit" };
#[cfg(usart_v1)] #[cfg(usart_v1)]
@ -886,7 +886,7 @@ fn configure(r: Regs, config: &Config, pclk_freq: Hertz, kind: Kind, enable_rx:
"Using {} oversampling, desired baudrate: {}, actual baudrate: {}", "Using {} oversampling, desired baudrate: {}, actual baudrate: {}",
oversampling, oversampling,
config.baudrate, config.baudrate,
pclk_freq.0 / brr pclk_freq.0 / div
); );
unsafe { unsafe {