public inbox for linux-arm-kernel@lists.infradead.org 
 help / color / mirror / Atom feed
From: Vladimir Murzin <vladimir.murzin@arm•com>
To: Mark Rutland <mark.rutland@arm•com>,
	linux-arm-kernel@lists•infradead.org, kvmarm@lists•linux.dev
Cc: broonie@kernel•org, catalin.marinas@arm•com, james.morse@arm•com,
	maz@kernel•org, oupton@kernel•org, tabba@google•com,
	will@kernel•org
Subject: Re: [PATCH 07/18] arm64: fpsimd: Use assembler for SVE instructions
Date: Wed, 27 May 2026 13:58:09 +0100	[thread overview]
Message-ID: <46c5ae49-e59c-4014-91d3-f00124897d20@arm.com> (raw)
In-Reply-To: <20260521132556.584676-8-mark.rutland@arm.com>

Hi Mark,

On 5/21/26 14:25, Mark Rutland wrote:
> Historically we supported assemblers which could not assemble SVE
> instructions. We dropped support for such assemblers in commit:
> 
>   118c40b7b503 ("kbuild: require gcc-8 and binutils-2.30")
> 
> Since that commit, all supported assemblers (binutils and LLVM) are
> capable of assembling SVE instructions, and there's no need for us to
> manually encode SVE instructions.
> 
> Rely on the assembler to encode SVE instructions, and remove the manual
> encoding. The various _sve_<insn> macros are kept for now, and will be
> cleaned up in subsequent patches.
> 
> There should be no functional change as a result of this patch.
> 
> Signed-off-by: Mark Rutland <mark.rutland@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: Mark Brown <broonie@kernel•org>
> Cc: Oliver Upton <oupton@kernel•org>
> Cc: Will Deacon <will@kernel•org>
> ---
>  arch/arm64/include/asm/fpsimdmacros.h | 64 +++++++--------------------
>  1 file changed, 16 insertions(+), 48 deletions(-)
> 
> diff --git a/arch/arm64/include/asm/fpsimdmacros.h b/arch/arm64/include/asm/fpsimdmacros.h
> index adf33d2da40c3..1122eea6daacf 100644
> --- a/arch/arm64/include/asm/fpsimdmacros.h
> +++ b/arch/arm64/include/asm/fpsimdmacros.h
> @@ -99,85 +99,53 @@
>  	.endif
>  .endm
>  
> -/* SVE instruction encodings for non-SVE-capable assemblers */
> -/* (pre binutils 2.28, all kernel capable clang versions support SVE) */
> +/* Deprecated macros for SVE instructions */
>  
>  /* STR (vector): STR Z\nz, [X\nxbase, #\offset, MUL VL] */

Nitpick:

all these comments now redundant and just repeat the code... I know they are gone by
the end of the series :)

>  .macro _sve_str_v nz, nxbase, offset=0
> -	_sve_check_zreg \nz
> -	_check_general_reg \nxbase
> -	_check_num (\offset), -0x100, 0xff
> -	.inst	0xe5804000			\
> -		| (\nz)				\
> -		| ((\nxbase) << 5)		\
> -		| (((\offset) & 7) << 10)	\
> -		| (((\offset) & 0x1f8) << 13)
> +	.arch_extension sve
> +	str	z\nz, [X\nxbase, #\offset, MUL VL]
>  .endm
>  
>  /* LDR (vector): LDR Z\nz, [X\nxbase, #\offset, MUL VL] */
>  .macro _sve_ldr_v nz, nxbase, offset=0
> -	_sve_check_zreg \nz
> -	_check_general_reg \nxbase
> -	_check_num (\offset), -0x100, 0xff
> -	.inst	0x85804000			\
> -		| (\nz)				\
> -		| ((\nxbase) << 5)		\
> -		| (((\offset) & 7) << 10)	\
> -		| (((\offset) & 0x1f8) << 13)
> +	.arch_extension sve
> +	ldr	z\nz, [X\nxbase, #\offset, MUL VL]
>  .endm
>  
>  /* STR (predicate): STR P\np, [X\nxbase, #\offset, MUL VL] */
>  .macro _sve_str_p np, nxbase, offset=0
> -	_sve_check_preg \np
> -	_check_general_reg \nxbase
> -	_check_num (\offset), -0x100, 0xff
> -	.inst	0xe5800000			\
> -		| (\np)				\
> -		| ((\nxbase) << 5)		\
> -		| (((\offset) & 7) << 10)	\
> -		| (((\offset) & 0x1f8) << 13)
> +	.arch_extension sve
> +	str	p\np, [X\nxbase, #\offset, MUL VL]
>  .endm
>  
>  /* LDR (predicate): LDR P\np, [X\nxbase, #\offset, MUL VL] */
>  .macro _sve_ldr_p np, nxbase, offset=0
> -	_sve_check_preg \np
> -	_check_general_reg \nxbase
> -	_check_num (\offset), -0x100, 0xff
> -	.inst	0x85800000			\
> -		| (\np)				\
> -		| ((\nxbase) << 5)		\
> -		| (((\offset) & 7) << 10)	\
> -		| (((\offset) & 0x1f8) << 13)
> +	.arch_extension sve
> +	ldr p\np, [x\nxbase, #\offset, MUL VL]
>  .endm
>  
>  /* RDVL X\nx, #\imm */
>  .macro _sve_rdvl nx, imm
> -	_check_general_reg \nx
> -	_check_num (\imm), -0x20, 0x1f
> -	.inst	0x04bf5000			\
> -		| (\nx)				\
> -		| (((\imm) & 0x3f) << 5)
> +	.arch_extension sve
> +	rdvl x\nx, #\imm
>  .endm
>  
>  /* RDFFR (unpredicated): RDFFR P\np.B */
>  .macro _sve_rdffr np
> -	_sve_check_preg \np
> -	.inst	0x2519f000			\
> -		| (\np)
> +	.arch_extension sve
> +	rdffr p\np\().b
>  .endm
>  
>  /* WRFFR P\np.B */
>  .macro _sve_wrffr np
> -	_sve_check_preg \np
> -	.inst	0x25289000			\
> -		| ((\np) << 5)

Missing ".arch_extension sve"?

> +	wrffr p\np\().b
>  .endm
>  
>  /* PFALSE P\np.B */
>  .macro _sve_pfalse np
> -	_sve_check_preg \np
> -	.inst	0x2518e400			\
> -		| (\np)
> +	.arch_extension sve
> +	pfalse	p\np\().b
>  .endm
>  
>  /* SME instruction encodings for non-SME-capable assemblers */
> -- 2.30.2
> 



  parent reply	other threads:[~2026-05-27 12:58 UTC|newest]

Thread overview: 78+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-05-21 13:25 [PATCH 00/18] arm64+KVM: FPSIMD/SVE/SME cleanups Mark Rutland
2026-05-21 13:25 ` [PATCH 01/18] KVM: arm64: Don't include <asm/fpsimdmacros.h> Mark Rutland
2026-05-26 14:18   ` Mark Brown
2026-05-27 10:10   ` Vladimir Murzin
2026-05-21 13:25 ` [PATCH 02/18] KVM: arm64: Don't override FFR save/restore argument Mark Rutland
2026-05-26 14:27   ` Mark Brown
2026-05-27 10:16   ` Vladimir Murzin
2026-05-21 13:25 ` [PATCH 03/18] KVM: arm64: pkvm: Save host FPMR in host cpu context Mark Rutland
2026-05-27 10:29   ` Vladimir Murzin
2026-05-21 13:25 ` [PATCH 04/18] KVM: arm64: pkvm: Remove struct cpu_sve_state Mark Rutland
2026-05-27 11:58   ` Vladimir Murzin
2026-05-27 16:02     ` Mark Rutland
2026-05-27 16:11       ` Vladimir Murzin
2026-05-28 15:09         ` Mark Rutland
2026-05-28 15:12           ` Vladimir Murzin
2026-05-21 13:25 ` [PATCH 05/18] arm64: fpsimd: Fold sve_init_regs() into do_sve_acc() Mark Rutland
2026-05-26 15:28   ` Mark Brown
2026-05-27 12:05   ` Vladimir Murzin
2026-05-21 13:25 ` [PATCH 06/18] arm64: fpsimd: Remove sve_set_vq() and sme_set_vq() Mark Rutland
2026-05-26 15:42   ` Mark Brown
2026-05-27 12:50   ` Vladimir Murzin
2026-05-21 13:25 ` [PATCH 07/18] arm64: fpsimd: Use assembler for SVE instructions Mark Rutland
2026-05-26 15:43   ` Mark Brown
2026-05-27 12:58   ` Vladimir Murzin [this message]
2026-05-27 16:10     ` Mark Rutland
2026-05-21 13:25 ` [PATCH 08/18] arm64: fpsimd: Use assembler for baseline SME instructions Mark Rutland
2026-05-26 15:45   ` Mark Brown
2026-05-27 13:06   ` Vladimir Murzin
2026-05-21 13:25 ` [PATCH 09/18] arm64: fpsimd: Move sve_get_vl() and sme_get_vl() inline Mark Rutland
2026-05-26 15:47   ` Mark Brown
2026-05-27 13:18   ` Vladimir Murzin
2026-05-21 13:25 ` [PATCH 10/18] arm64: sysreg: Add FPCR and FPSR Mark Rutland
2026-05-26 15:55   ` Mark Brown
2026-05-26 16:51     ` Mark Rutland
2026-05-26 16:54       ` Mark Brown
2026-05-21 13:25 ` [PATCH 11/18] arm64: fpsimd: Split FPSR/FPCR from SVE save/restore Mark Rutland
2026-05-26 16:28   ` Mark Brown
2026-05-27 13:51     ` Mark Rutland
2026-05-27 14:13       ` Mark Brown
2026-05-27 16:13         ` Mark Rutland
2026-05-27 13:44   ` Vladimir Murzin
2026-05-21 13:25 ` [PATCH 12/18] arm64: fpsimd: Move fpsimd save/restore inline Mark Rutland
2026-05-26 16:44   ` Mark Brown
2026-05-28 16:15     ` Mark Rutland
2026-05-28 16:39       ` Mark Brown
2026-05-27 14:49   ` Vladimir Murzin
2026-05-27 15:34     ` Mark Rutland
2026-05-27 16:13       ` Vladimir Murzin
2026-05-21 13:25 ` [PATCH 13/18] arm64: fpsimd: Use opaque type for SVE state Mark Rutland
2026-05-26 16:53   ` Mark Brown
2026-05-28  9:45   ` Vladimir Murzin
2026-05-28 16:25     ` Mark Rutland
2026-05-21 13:25 ` [PATCH 14/18] arm64: fpsimd: Use opaque type for SME state Mark Rutland
2026-05-26 16:56   ` Mark Brown
2026-05-28  9:51   ` Vladimir Murzin
2026-05-21 13:25 ` [PATCH 15/18] arm64: fpsimd: Move SVE save/restore inline Mark Rutland
2026-05-27 12:29   ` Mark Brown
2026-05-28 10:39   ` Vladimir Murzin
2026-05-21 13:25 ` [PATCH 16/18] arm64: fpsimd: Move sve_flush_live() inline Mark Rutland
2026-05-27 12:54   ` Mark Brown
2026-05-27 16:23     ` Mark Rutland
2026-05-28 10:49   ` Vladimir Murzin
2026-05-21 13:25 ` [PATCH 17/18] arm64: fpsimd: Move SME save/restore inline Mark Rutland
2026-05-26 14:08   ` Mark Rutland
2026-05-26 14:39     ` Vladimir Murzin
2026-05-26 15:28       ` Mark Rutland
2026-05-26 16:38         ` Mark Rutland
2026-05-27  9:00           ` Vladimir Murzin
2026-05-29  9:10           ` Mark Rutland
2026-05-28 12:30   ` Vladimir Murzin
2026-05-28 14:39     ` Mark Rutland
2026-05-21 13:25 ` [PATCH 18/18] arm64: fpsimd: Remove <asm/fpsimdmacros.h> Mark Rutland
2026-05-28 13:10   ` Vladimir Murzin
2026-05-27  8:07 ` [PATCH 00/18] arm64+KVM: FPSIMD/SVE/SME cleanups Marc Zyngier
2026-05-27 10:32   ` Mark Rutland
2026-05-27 14:36     ` Will Deacon
2026-05-28 13:21 ` Vladimir Murzin
2026-05-28 16:28   ` Mark Rutland

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=46c5ae49-e59c-4014-91d3-f00124897d20@arm.com \
    --to=vladimir.murzin@arm$(echo .)com \
    --cc=broonie@kernel$(echo .)org \
    --cc=catalin.marinas@arm$(echo .)com \
    --cc=james.morse@arm$(echo .)com \
    --cc=kvmarm@lists$(echo .)linux.dev \
    --cc=linux-arm-kernel@lists$(echo .)infradead.org \
    --cc=mark.rutland@arm$(echo .)com \
    --cc=maz@kernel$(echo .)org \
    --cc=oupton@kernel$(echo .)org \
    --cc=tabba@google$(echo .)com \
    --cc=will@kernel$(echo .)org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox