From d470afd2066b398866016685efcaf5eff1a5052e Mon Sep 17 00:00:00 2001
From: Johan Anderholm <johan.anderholm@gmail.com>
Date: Wed, 11 Jun 2025 18:42:32 +0200
Subject: [PATCH] Use la/jr pseudoinstructions for main function call
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Replace direct jal with load address and jump register pseudoinstructions
to support main functions located beyond the ±1MB range of direct jumps.
---
 riscv-rt/CHANGELOG.md | 5 +++++
 riscv-rt/src/asm.rs   | 3 ++-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/riscv-rt/CHANGELOG.md b/riscv-rt/CHANGELOG.md
index c533c6da..56191077 100644
--- a/riscv-rt/CHANGELOG.md
+++ b/riscv-rt/CHANGELOG.md
@@ -7,6 +7,11 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ## [Unreleased]
 
+### Changed
+
+- Main function no longer needs to be close to _start. A linker script may copy
+  all code to RAM and keep .init in flash/ROM.
+
 ## [v0.15.0] - 2025-06-10
 
 ### Added
diff --git a/riscv-rt/src/asm.rs b/riscv-rt/src/asm.rs
index e8e19199..6e4c263d 100644
--- a/riscv-rt/src/asm.rs
+++ b/riscv-rt/src/asm.rs
@@ -217,7 +217,8 @@ cfg_global_asm!(
     ld a1, 8 * 1(sp)
     ld a2, 8 * 2(sp)
     addi sp, sp, 8 * 4",
-    "jal zero, main
+    "la t0, main
+    jr t0
     .cfi_endproc",
 );