firmware: made some rust firmware to test

Had some issues due to lack of startup code (stack pointer was unset, leading to underflow in address space), so decided to just get the rust FW started instead of finding some startup code to use.
2023-01-22 15:20:27 -07:00 · 2023-01-22 15:20:27 -07:00 · 1cfa5a47de
commit 1cfa5a47de
parent a1853dbe81
10 changed files with 293 additions and 6 deletions
--- a/firmware/.cargo/config
+++ b/firmware/.cargo/config
@ -0,0 +1,8 @@
+[target.riscv32i-unknown-none-elf]
+rustflags = [
+  "-C", "link-arg=-Tmemory.x",
+  "-C", "link-arg=-Tlink.x",
+]
+
+[build]
+target = "riscv32i-unknown-none-elf"
--- a/firmware/.gitignore
+++ b/firmware/.gitignore
@ -0,0 +1,2 @@
+target/
+*.bin
--- a/firmware/Cargo.lock
+++ b/firmware/Cargo.lock
@ -0,0 +1,183 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "aho-corasick"
+version = "0.7.20"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cc936419f96fa211c1b9166887b38e5e40b19958e5b895be7c1f93adec7071ac"
+dependencies = [
+ "memchr",
+]
+
+[[package]]
+name = "bit_field"
+version = "0.10.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dcb6dd1c2376d2e096796e234a70e17e94cc2d5d54ff8ce42b28cef1d0d359a4"
+
+[[package]]
+name = "critical-section"
+version = "1.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6548a0ad5d2549e111e1f6a11a6c2e2d00ce6a3dafe22948d67c2b443f775e52"
+
+[[package]]
+name = "embedded-hal"
+version = "0.2.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "35949884794ad573cf46071e41c9b60efb0cb311e3ca01f7af807af1debc66ff"
+dependencies = [
+ "nb 0.1.3",
+ "void",
+]
+
+[[package]]
+name = "fw"
+version = "0.1.0"
+dependencies = [
+ "panic-halt",
+ "riscv-rt",
+]
+
+[[package]]
+name = "lazy_static"
+version = "1.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
+
+[[package]]
+name = "memchr"
+version = "2.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2dffe52ecf27772e601905b7522cb4ef790d2cc203488bbd0e2fe85fcb74566d"
+
+[[package]]
+name = "nb"
+version = "0.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "801d31da0513b6ec5214e9bf433a77966320625a37860f910be265be6e18d06f"
+dependencies = [
+ "nb 1.0.0",
+]
+
+[[package]]
+name = "nb"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "546c37ac5d9e56f55e73b677106873d9d9f5190605e41a856503623648488cae"
+
+[[package]]
+name = "panic-halt"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "de96540e0ebde571dc55c73d60ef407c653844e6f9a1e2fdbd40c07b9252d812"
+
+[[package]]
+name = "proc-macro2"
+version = "1.0.50"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6ef7d57beacfaf2d8aee5937dab7b7f28de3cb8b1828479bb5de2a7106f2bae2"
+dependencies = [
+ "unicode-ident",
+]
+
+[[package]]
+name = "quote"
+version = "1.0.23"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8856d8364d252a14d474036ea1358d63c9e6965c8e5c1885c18f73d70bff9c7b"
+dependencies = [
+ "proc-macro2",
+]
+
+[[package]]
+name = "r0"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bd7a31eed1591dcbc95d92ad7161908e72f4677f8fabf2a32ca49b4237cbf211"
+
+[[package]]
+name = "regex"
+version = "1.7.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "48aaa5748ba571fb95cd2c85c09f629215d3a6ece942baa100950af03a34f733"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-syntax"
+version = "0.6.28"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "456c603be3e8d448b072f410900c09faf164fbce2d480456f50eea6e25f9c848"
+
+[[package]]
+name = "riscv"
+version = "0.10.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "aa3145d2fae3778b1e31ec2e827b228bdc6abd9b74bb5705ba46dcb82069bc4f"
+dependencies = [
+ "bit_field",
+ "critical-section",
+ "embedded-hal",
+]
+
+[[package]]
+name = "riscv-rt"
+version = "0.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "102c52c89defde24dedf9ac077cc69df77b85aa2400dd2d5aad6eea6a6a5c089"
+dependencies = [
+ "r0",
+ "riscv",
+ "riscv-rt-macros",
+ "riscv-target",
+]
+
+[[package]]
+name = "riscv-rt-macros"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f38509d7b17c2f604ceab3e5ff8ac97bb8cd2f544688c512be75c715edaf4daf"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "riscv-target"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "88aa938cda42a0cf62a20cfe8d139ff1af20c2e681212b5b34adb5a58333f222"
+dependencies = [
+ "lazy_static",
+ "regex",
+]
+
+[[package]]
+name = "syn"
+version = "1.0.107"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1f4064b5b16e03ae50984a5a8ed5d4f8803e6bc1fd170a3cda91a1be4b18e3f5"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "unicode-ident",
+]
+
+[[package]]
+name = "unicode-ident"
+version = "1.0.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "84a22b9f218b40614adcb3f4ff08b703773ad44fa9423e4e0d346d5db86e4ebc"
+
+[[package]]
+name = "void"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6a02e4885ed3bc0f2de90ea6dd45ebcbb66dacffe03547fadbb0eeae2770887d"
--- a/firmware/Cargo.toml
+++ b/firmware/Cargo.toml
@ -0,0 +1,10 @@
+[package]
+name = "fw"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+riscv-rt = "0.11.0"
+panic-halt = "0.2.0"
--- a/firmware/README.md
+++ b/firmware/README.md
@ -0,0 +1,3 @@
+# Firmware
+
+This was set up according to docs here: https://docs.rs/riscv-rt/latest/riscv_rt/
--- a/firmware/build.rs
+++ b/firmware/build.rs
@ -0,0 +1,14 @@
+use std::env;
+use std::fs;
+use std::path::PathBuf;
+
+fn main() {
+    let out_dir = PathBuf::from(env::var("OUT_DIR").unwrap());
+
+    // Put the linker script somewhere the linker can find it.
+    fs::write(out_dir.join("memory.x"), include_bytes!("memory.x")).unwrap();
+    println!("cargo:rustc-link-search={}", out_dir.display());
+    println!("cargo:rerun-if-changed=memory.x");
+
+    println!("cargo:rerun-if-changed=build.rs");
+}
--- a/firmware/hello_world_c/Makefile
+++ b/firmware/hello_world_c/Makefile
@ -2,7 +2,7 @@ PREFIX := riscv64-unknown-elf-
 CC := $(PREFIX)gcc
 OBJCOPY := $(PREFIX)objcopy

-ARGS := -mabi=ilp32 -march=rv32im -ffreestanding -nostdlib -Wl,-Bstatic,-T,memory.ld,--strip-debug
+ARGS := -mabi=ilp32 -march=rv32im -ffreestanding -nostdlib -Wl,-Bstatic,-T,memory.ld -g

 SOURCES := main.c
 INCLUDES := uart.h
--- a/firmware/hello_world_c/main.c
+++ b/firmware/hello_world_c/main.c
@ -1,13 +1,28 @@
 #include "uart.h"

 #include <stdint.h>
+#include <stdbool.h>

 void write_cstring(const char* string);
 void write_char(char c);
+void toggle_led();
+
+#define LED *((uint32_t*) 0x01002000)


 int main() {
+    uint32_t i = 0;
+    bool toggle = false;
    for (;;) {
+        if (i >= 100) {
+            i = 0;
+            if (toggle) {
+                LED = 1;
+            } else {
+                LED = 0;
+            }
+        }
+
        write_char('H');
        write_char('e');
        write_char('l');
@ -22,17 +37,19 @@ int main() {
        write_char('!');
        write_char('\n');
        write_char('\r');
+
+        i += 1;
    }
 }


 void write_char(char c) {
-    while (!UART0->TXEMPTY);
+    //while (!UART0->TXEMPTY);

-    // Wait for room to clear up
-    if (!UART0->TXFULL) {
-        UART0->RXTX = c;
-    }
+    //// Wait for room to clear up
+    //if (!UART0->TXFULL) {
+    //    UART0->RXTX = c;
+    //}
 }
 void write_cstring(const char* string) {
    int i = 0;
@ -52,3 +69,8 @@ void write_cstring(const char* string) {
    }

 }
+
+void toggle_led() {
+    LED = !LED;
+    write_char('0' + LED);
+}
--- a/firmware/memory.x
+++ b/firmware/memory.x
@ -0,0 +1,12 @@
+MEMORY
+{
+  RAM : ORIGIN = 0x01001000, LENGTH = 4K
+  FLASH : ORIGIN = 0x01000000, LENGTH = 4K
+}
+
+REGION_ALIAS("REGION_TEXT", FLASH);
+REGION_ALIAS("REGION_RODATA", FLASH);
+REGION_ALIAS("REGION_DATA", RAM);
+REGION_ALIAS("REGION_BSS", RAM);
+REGION_ALIAS("REGION_HEAP", RAM);
+REGION_ALIAS("REGION_STACK", RAM);
--- a/firmware/src/main.rs
+++ b/firmware/src/main.rs
@ -0,0 +1,33 @@
+#![no_std]
+#![no_main]
+
+extern crate panic_halt;
+
+use core::{arch::asm, ptr::write};
+
+use riscv_rt::entry;
+
+// use `main` as the entry point of this application
+// `main` is not allowed to return
+#[entry]
+fn main() -> ! {
+    // do something here
+    loop {
+        unsafe {
+            write(0x01002000 as *mut u32, 0);
+            busy_wait(10_000_000);
+            write(0x01002000 as *mut u32, 1);
+            busy_wait(10_000_000);
+        }
+    }
+}
+
+fn busy_wait(num_nops: u32) {
+    for _ in 0..num_nops {
+        unsafe { asm!("nop"); }
+    }
+}
+
+fn write_led(val: u32) {
+    unsafe { write(0x01002000 as *mut u32, val); }
+}