summaryrefslogtreecommitdiffstats
path: root/arch/arm64/include/asm/lse.h
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm64/include/asm/lse.h')
-rw-r--r--arch/arm64/include/asm/lse.h45
1 files changed, 45 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/lse.h b/arch/arm64/include/asm/lse.h
new file mode 100644
index 000000000..c503db8e7
--- /dev/null
+++ b/arch/arm64/include/asm/lse.h
@@ -0,0 +1,45 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ASM_LSE_H
+#define __ASM_LSE_H
+
+#include <asm/atomic_ll_sc.h>
+
+#ifdef CONFIG_ARM64_LSE_ATOMICS
+
+#define __LSE_PREAMBLE ".arch_extension lse\n"
+
+#include <linux/compiler_types.h>
+#include <linux/export.h>
+#include <linux/jump_label.h>
+#include <linux/stringify.h>
+#include <asm/alternative.h>
+#include <asm/alternative-macros.h>
+#include <asm/atomic_lse.h>
+#include <asm/cpucaps.h>
+
+static __always_inline bool system_uses_lse_atomics(void)
+{
+ return alternative_has_feature_likely(ARM64_HAS_LSE_ATOMICS);
+}
+
+#define __lse_ll_sc_body(op, ...) \
+({ \
+ system_uses_lse_atomics() ? \
+ __lse_##op(__VA_ARGS__) : \
+ __ll_sc_##op(__VA_ARGS__); \
+})
+
+/* In-line patching at runtime */
+#define ARM64_LSE_ATOMIC_INSN(llsc, lse) \
+ ALTERNATIVE(llsc, __LSE_PREAMBLE lse, ARM64_HAS_LSE_ATOMICS)
+
+#else /* CONFIG_ARM64_LSE_ATOMICS */
+
+static inline bool system_uses_lse_atomics(void) { return false; }
+
+#define __lse_ll_sc_body(op, ...) __ll_sc_##op(__VA_ARGS__)
+
+#define ARM64_LSE_ATOMIC_INSN(llsc, lse) llsc
+
+#endif /* CONFIG_ARM64_LSE_ATOMICS */
+#endif /* __ASM_LSE_H */