From: Mark Rutland <mark.rutland@arm.com>
Date: Wed, 3 Jun 2026 11:06:21 +0000 (+0100)
Subject: arm64: fpsimd: Move sve_get_vl() and sme_get_vl() inline
X-Git-Url: http://git.ipfire.org/gitweb/?a=commitdiff_plain;h=3f26d7c6544cae590d8aa380aac62fe455dac2c3;p=thirdparty%2Fkernel%2Flinux.git

arm64: fpsimd: Move sve_get_vl() and sme_get_vl() inline

The sve_get_vl() and sme_get_vl() functions are wrappers for the RDVL
and RDSVL instructions respectively. There's no need for those to be
out-of-line.

Replace the out-of-line assembly functions with equivalent inline
functions.

The _sve_rdvl assembly macro is unused, and so it is removed. The
_sme_rdsvl assembly macro is still used elsewhere, and so is kept for
now.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Vladimir Murzin <vladimir.murzin@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Fuad Tabba <tabba@google.com>
Cc: James Morse <james.morse@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Oliver Upton <oupton@kernel.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
---

diff --git a/arch/arm64/include/asm/fpsimd.h b/arch/arm64/include/asm/fpsimd.h
index 8efa3c0402a7a..36cf528e64971 100644
--- a/arch/arm64/include/asm/fpsimd.h
+++ b/arch/arm64/include/asm/fpsimd.h
@@ -22,6 +22,9 @@
 #include <linux/stddef.h>
 #include <linux/types.h>
 
+#define __SVE_PREAMBLE		".arch_extension sve\n"
+#define __SME_PREAMBLE		".arch_extension sme\n"
+
 /* Masks for extracting the FPSR and FPCR from the FPSCR */
 #define VFP_FPSCR_STAT_MASK	0xf800009f
 #define VFP_FPSCR_CTRL_MASK	0x07f79f00
@@ -141,11 +144,23 @@ static inline void *thread_zt_state(struct thread_struct *thread)
 	return thread->sme_state + ZA_SIG_REGS_SIZE(sme_vq);
 }
 
+static inline unsigned int sve_get_vl(void)
+{
+	unsigned int vl;
+
+	asm volatile(
+	__SVE_PREAMBLE
+	"	rdvl %x[vl], #1\n"
+	: [vl] "=r" (vl)
+	);
+
+	return vl;
+}
+
 extern void sve_save_state(void *state, u32 *pfpsr, int save_ffr);
 extern void sve_load_state(void const *state, u32 const *pfpsr,
 			   int restore_ffr);
 extern void sve_flush_live(bool flush_ffr, unsigned long vq_minus_1);
-extern unsigned int sve_get_vl(void);
 extern void sme_save_state(void *state, int zt);
 extern void sme_load_state(void const *state, int zt);
 
@@ -400,8 +415,20 @@ static inline int sme_max_virtualisable_vl(void)
 	return vec_max_virtualisable_vl(ARM64_VEC_SME);
 }
 
+static inline unsigned int sme_get_vl(void)
+{
+	unsigned int vl;
+
+	asm volatile(
+	__SME_PREAMBLE
+	"	rdsvl %x[vl], #1\n"
+	: [vl] "=r" (vl)
+	);
+
+	return vl;
+}
+
 extern void sme_alloc(struct task_struct *task, bool flush);
-extern unsigned int sme_get_vl(void);
 extern int sme_set_current_vl(unsigned long arg);
 extern int sme_get_current_vl(void);
 extern void sme_suspend_exit(void);
diff --git a/arch/arm64/include/asm/fpsimdmacros.h b/arch/arm64/include/asm/fpsimdmacros.h
index 4a9bf46e52913..c724fcad7ee02 100644
--- a/arch/arm64/include/asm/fpsimdmacros.h
+++ b/arch/arm64/include/asm/fpsimdmacros.h
@@ -125,12 +125,6 @@
 	ldr p\np, [x\nxbase, #\offset, MUL VL]
 .endm
 
-/* RDVL X\nx, #\imm */
-.macro _sve_rdvl nx, imm
-	.arch_extension sve
-	rdvl x\nx, #\imm
-.endm
-
 /* RDFFR (unpredicated): RDFFR P\np.B */
 .macro _sve_rdffr np
 	.arch_extension sve
diff --git a/arch/arm64/kernel/entry-fpsimd.S b/arch/arm64/kernel/entry-fpsimd.S
index bfa73f26653f2..a124c6d3766cf 100644
--- a/arch/arm64/kernel/entry-fpsimd.S
+++ b/arch/arm64/kernel/entry-fpsimd.S
@@ -57,11 +57,6 @@ SYM_FUNC_START(sve_load_state)
 	ret
 SYM_FUNC_END(sve_load_state)
 
-SYM_FUNC_START(sve_get_vl)
-	_sve_rdvl	0, 1
-	ret
-SYM_FUNC_END(sve_get_vl)
-
 /*
  * Zero all SVE registers but the first 128-bits of each vector
  *
@@ -84,11 +79,6 @@ SYM_FUNC_END(sve_flush_live)
 
 #ifdef CONFIG_ARM64_SME
 
-SYM_FUNC_START(sme_get_vl)
-	_sme_rdsvl	0, 1
-	ret
-SYM_FUNC_END(sme_get_vl)
-
 /*
  * Save the ZA and ZT state
  *