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Diffstat (limited to 'arch/openrisc/include/asm/jump_label.h')
-rw-r--r--arch/openrisc/include/asm/jump_label.h72
1 files changed, 72 insertions, 0 deletions
diff --git a/arch/openrisc/include/asm/jump_label.h b/arch/openrisc/include/asm/jump_label.h
new file mode 100644
index 000000000000..3ec0f4e19f9c
--- /dev/null
+++ b/arch/openrisc/include/asm/jump_label.h
@@ -0,0 +1,72 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2025 Chen Miao
+ *
+ * Based on arch/arm/include/asm/jump_label.h
+ */
+#ifndef __ASM_OPENRISC_JUMP_LABEL_H
+#define __ASM_OPENRISC_JUMP_LABEL_H
+
+#ifndef __ASSEMBLER__
+
+#include <linux/types.h>
+#include <asm/insn-def.h>
+
+#define HAVE_JUMP_LABEL_BATCH
+
+#define JUMP_LABEL_NOP_SIZE OPENRISC_INSN_SIZE
+
+/**
+ * JUMP_TABLE_ENTRY - Create a jump table entry
+ * @key: Jump key identifier (typically a symbol address)
+ * @label: Target label address
+ *
+ * This macro creates a jump table entry in the dedicated kernel section (__jump_table).
+ * Each entry contains the following information:
+ * Offset from current instruction to jump instruction (1b - .)
+ * Offset from current instruction to target label (label - .)
+ * Offset from current instruction to key identifier (key - .)
+ */
+#define JUMP_TABLE_ENTRY(key, label) \
+ ".pushsection __jump_table, \"aw\" \n\t" \
+ ".align 4 \n\t" \
+ ".long 1b - ., " label " - . \n\t" \
+ ".long " key " - . \n\t" \
+ ".popsection \n\t"
+
+#define ARCH_STATIC_BRANCH_ASM(key, label) \
+ ".align 4 \n\t" \
+ "1: l.nop \n\t" \
+ " l.nop \n\t" \
+ JUMP_TABLE_ENTRY(key, label)
+
+static __always_inline bool arch_static_branch(struct static_key *const key,
+ const bool branch)
+{
+ asm goto (ARCH_STATIC_BRANCH_ASM("%0", "%l[l_yes]")
+ ::"i"(&((char *)key)[branch])::l_yes);
+
+ return false;
+l_yes:
+ return true;
+}
+
+#define ARCH_STATIC_BRANCH_JUMP_ASM(key, label) \
+ ".align 4 \n\t" \
+ "1: l.j " label " \n\t" \
+ " l.nop \n\t" \
+ JUMP_TABLE_ENTRY(key, label)
+
+static __always_inline bool
+arch_static_branch_jump(struct static_key *const key, const bool branch)
+{
+ asm goto (ARCH_STATIC_BRANCH_JUMP_ASM("%0", "%l[l_yes]")
+ ::"i"(&((char *)key)[branch])::l_yes);
+
+ return false;
+l_yes:
+ return true;
+}
+
+#endif /* __ASSEMBLER__ */
+#endif /* __ASM_OPENRISC_JUMP_LABEL_H */