1 files changed, 51 insertions, 0 deletions
diff --git a/arch/openrisc/kernel/jump_label.c b/arch/openrisc/kernel/jump_label.c
new file mode 100644
index 000000000000..ab7137c23b46
--- /dev/null
+++ b/arch/openrisc/kernel/jump_label.c
@@ -0,0 +1,51 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2025 Chen Miao
+ *
+ * Based on arch/arm/kernel/jump_label.c
+ */
+#include <linux/jump_label.h>
+#include <linux/kernel.h>
+#include <linux/memory.h>
+#include <asm/bug.h>
+#include <asm/cacheflush.h>
+#include <asm/text-patching.h>
+
+bool arch_jump_label_transform_queue(struct jump_entry *entry,
+				     enum jump_label_type type)
+{
+	void *addr = (void *)jump_entry_code(entry);
+	u32 insn;
+
+	if (type == JUMP_LABEL_JMP) {
+		long offset;
+
+		offset = jump_entry_target(entry) - jump_entry_code(entry);
+		/*
+		 * The actual maximum range of the l.j instruction's offset is -134,217,728
+		 * ~ 134,217,724 (sign 26-bit imm).
+		 * For the original jump range, we need to right-shift N by 2 to obtain the
+		 * instruction's offset.
+		 */
+		WARN_ON_ONCE(offset < -134217728 || offset > 134217724);
+
+		/* 26bit imm mask */
+		offset = (offset >> 2) & 0x03ffffff;
+
+		insn = offset;
+	} else {
+		insn = OPENRISC_INSN_NOP;
+	}
+
+	if (early_boot_irqs_disabled)
+		copy_to_kernel_nofault(addr, &insn, sizeof(insn));
+	else
+		patch_insn_write(addr, insn);
+
+	return true;
+}
+
+void arch_jump_label_transform_apply(void)
+{
+	kick_all_cpus_sync();
+}