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Diffstat (limited to 'arch/arm64/include/asm/sysreg.h')
-rw-r--r--arch/arm64/include/asm/sysreg.h23
1 files changed, 15 insertions, 8 deletions
diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index 6455db1b54fd..9df51accbb02 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -52,7 +52,7 @@
#ifndef CONFIG_BROKEN_GAS_INST
-#ifdef __ASSEMBLY__
+#ifdef __ASSEMBLER__
// The space separator is omitted so that __emit_inst(x) can be parsed as
// either an assembler directive or an assembler macro argument.
#define __emit_inst(x) .inst(x)
@@ -71,11 +71,11 @@
(((x) >> 24) & 0x000000ff))
#endif /* CONFIG_CPU_BIG_ENDIAN */
-#ifdef __ASSEMBLY__
+#ifdef __ASSEMBLER__
#define __emit_inst(x) .long __INSTR_BSWAP(x)
-#else /* __ASSEMBLY__ */
+#else /* __ASSEMBLER__ */
#define __emit_inst(x) ".long " __stringify(__INSTR_BSWAP(x)) "\n\t"
-#endif /* __ASSEMBLY__ */
+#endif /* __ASSEMBLER__ */
#endif /* CONFIG_BROKEN_GAS_INST */
@@ -1129,9 +1129,7 @@
#define gicr_insn(insn) read_sysreg_s(GICV5_OP_GICR_##insn)
#define gic_insn(v, insn) write_sysreg_s(v, GICV5_OP_GIC_##insn)
-#define ARM64_FEATURE_FIELD_BITS 4
-
-#ifdef __ASSEMBLY__
+#ifdef __ASSEMBLER__
.macro mrs_s, rt, sreg
__emit_inst(0xd5200000|(\sreg)|(.L__gpr_num_\rt))
@@ -1220,10 +1218,19 @@
__val; \
})
+/*
+ * The "Z" constraint combined with the "%x0" template should be enough
+ * to force XZR generation if (v) is a constant 0 value but LLVM does not
+ * yet understand that modifier/constraint combo so a conditional is required
+ * to nudge the compiler into using XZR as a source for a 0 constant value.
+ */
#define write_sysreg_s(v, r) do { \
u64 __val = (u64)(v); \
u32 __maybe_unused __check_r = (u32)(r); \
- asm volatile(__msr_s(r, "%x0") : : "rZ" (__val)); \
+ if (__builtin_constant_p(__val) && __val == 0) \
+ asm volatile(__msr_s(r, "xzr")); \
+ else \
+ asm volatile(__msr_s(r, "%x0") : : "r" (__val)); \
} while (0)
/*