[PATCHv3 02/17] arm64: add C wrappers for SET_PSTATE_*()

Mark Rutland mark.rutland at arm.com
Mon Oct 26 09:31:41 EDT 2020


To make callsites easier to read, add trivial C wrappers for the
SET_PSTATE_*() helpers, and convert trivial uses over to these. The new
wrappers will be used further in subsequent patches.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland at arm.com>
Cc: Catalin Marinas <catalin.marinas at arm.com>
Cc: Christoph Hellwig <hch at lst.de>
Cc: James Morse <james.morse at arm.com>
Cc: Will Deacon <will at kernel.org>
---
 arch/arm64/include/asm/sysreg.h | 4 ++++
 arch/arm64/kernel/cpufeature.c  | 2 +-
 arch/arm64/kernel/proton-pack.c | 4 ++--
 3 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index d52c1b3ce5894..bfd5f724c7ff0 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -98,6 +98,10 @@
 #define SET_PSTATE_SSBS(x)		__emit_inst(0xd500401f | PSTATE_SSBS | ((!!x) << PSTATE_Imm_shift))
 #define SET_PSTATE_TCO(x)		__emit_inst(0xd500401f | PSTATE_TCO | ((!!x) << PSTATE_Imm_shift))
 
+#define set_pstate_pan(x)		asm volatile(SET_PSTATE_PAN(x))
+#define set_pstate_uao(x)		asm volatile(SET_PSTATE_UAO(x))
+#define set_pstate_ssbs(x)		asm volatile(SET_PSTATE_SSBS(x))
+
 #define __SYS_BARRIER_INSN(CRm, op2, Rt) \
 	__emit_inst(0xd5000000 | sys_insn(0, 3, 3, (CRm), (op2)) | ((Rt) & 0x1f))
 
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index dcc165b3fc046..4ff0369bd0b35 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -1598,7 +1598,7 @@ static void cpu_enable_pan(const struct arm64_cpu_capabilities *__unused)
 	WARN_ON_ONCE(in_interrupt());
 
 	sysreg_clear_set(sctlr_el1, SCTLR_EL1_SPAN, 0);
-	asm(SET_PSTATE_PAN(1));
+	set_pstate_pan(1);
 }
 #endif /* CONFIG_ARM64_PAN */
 
diff --git a/arch/arm64/kernel/proton-pack.c b/arch/arm64/kernel/proton-pack.c
index 25f3c80b5ffe4..d59f982fce3d1 100644
--- a/arch/arm64/kernel/proton-pack.c
+++ b/arch/arm64/kernel/proton-pack.c
@@ -539,12 +539,12 @@ static enum mitigation_state spectre_v4_enable_hw_mitigation(void)
 
 	if (spectre_v4_mitigations_off()) {
 		sysreg_clear_set(sctlr_el1, 0, SCTLR_ELx_DSSBS);
-		asm volatile(SET_PSTATE_SSBS(1));
+		set_pstate_ssbs(1);
 		return SPECTRE_VULNERABLE;
 	}
 
 	/* SCTLR_EL1.DSSBS was initialised to 0 during boot */
-	asm volatile(SET_PSTATE_SSBS(0));
+	set_pstate_ssbs(0);
 	return SPECTRE_MITIGATED;
 }
 
-- 
2.11.0




More information about the linux-arm-kernel mailing list