Merge #579

579: embassy-stm32: L1 family RCC fixes r=Dirbaio a=unrelentingtech



Co-authored-by: Greg V <greg@unrelenting.technology>

embassy-stm32/src/rcc/l1.rs

@@ -1,5 +1,5 @@
 use crate::pac::rcc::vals::{Hpre, Msirange, Plldiv, Pllmul, Pllsrc, Ppre, Sw};
-use crate::pac::RCC;
+use crate::pac::{FLASH, RCC};
 use crate::rcc::{set_freqs, Clocks};
 use crate::time::Hertz;
 use crate::time::U32Ext;
@@ -258,7 +258,7 @@ pub(crate) unsafe fn init(config: Config) {
                 PLLDiv::Div3 => freq / 3,
                 PLLDiv::Div4 => freq / 4,
             };
-            assert!(freq <= 32_u32.mhz().0);
+            assert!(freq <= 32_000_000);
 
             RCC.cfgr().write(move |w| {
                 w.set_pllmul(mul.into());
@@ -274,6 +274,13 @@ pub(crate) unsafe fn init(config: Config) {
         }
     };
 
+    // Set flash 64-bit access, prefetch and wait states
+    if sys_clk >= 16_000_000 {
+        FLASH.acr().write(|w| w.set_acc64(true));
+        FLASH.acr().modify(|w| w.set_prften(true));
+        FLASH.acr().modify(|w| w.set_latency(true));
+    }
+
     RCC.cfgr().modify(|w| {
         w.set_sw(sw);
         w.set_hpre(config.ahb_pre.into());

examples/stm32l1/build.rs

@@ -1,34 +1,4 @@
-//! This build script copies the `memory.x` file from the crate root into
-//! a directory where the linker can always find it at build time.
-//! For many projects this is optional, as the linker always searches the
-//! project root directory -- wherever `Cargo.toml` is. However, if you
-//! are using a workspace or have a more complicated build setup, this
-//! build script becomes required. Additionally, by requesting that
-//! Cargo re-run the build script whenever `memory.x` is changed,
-//! updating `memory.x` ensures a rebuild of the application with the
-//! new memory settings.
-
-use std::env;
-use std::fs::File;
-use std::io::Write;
-use std::path::PathBuf;
-
 fn main() {
-    // Put `memory.x` in our output directory and ensure it's
-    // on the linker search path.
-    let out = &PathBuf::from(env::var_os("OUT_DIR").unwrap());
-    File::create(out.join("memory.x"))
-        .unwrap()
-        .write_all(include_bytes!("memory.x"))
-        .unwrap();
-    println!("cargo:rustc-link-search={}", out.display());
-
-    // By default, Cargo will re-run a build script whenever
-    // any file in the project changes. By specifying `memory.x`
-    // here, we ensure the build script is only re-run when
-    // `memory.x` is changed.
-    println!("cargo:rerun-if-changed=memory.x");
-
     println!("cargo:rustc-link-arg-bins=--nmagic");
     println!("cargo:rustc-link-arg-bins=-Tlink.x");
     println!("cargo:rustc-link-arg-bins=-Tdefmt.x");

examples/stm32l1/memory.x

@@ -1,5 +0,0 @@
-MEMORY
-{
-  FLASH : ORIGIN = 0x08000000, LENGTH = 128K
-  RAM : ORIGIN = 0x20000000, LENGTH = 32K
-}

stm32-data

@@ -1 +1 @@
-Subproject commit c66033b9d220ce6d148a4c90f72acd1118861bb1
+Subproject commit 97877b42a7b14e753dcb3153221dc1f3865070d1