[v4,2/4] RISC-V: Factor out common code of __cpu_resume_enter()

Message ID 20230221023523.1498500-3-jeeheng.sia@starfivetech.com
State New
Headers
Series RISC-V Hibernation Support |

Commit Message

JeeHeng Sia Feb. 21, 2023, 2:35 a.m. UTC
  The cpu_resume() function is very similar for the suspend to disk and
suspend to ram cases. Factor out the common code into restore_csr macro
and restore_reg macro.

Signed-off-by: Sia Jee Heng <jeeheng.sia@starfivetech.com>
---
 arch/riscv/include/asm/assembler.h | 62 ++++++++++++++++++++++++++++++
 arch/riscv/kernel/suspend_entry.S  | 34 ++--------------
 2 files changed, 65 insertions(+), 31 deletions(-)
 create mode 100644 arch/riscv/include/asm/assembler.h
  

Comments

Andrew Jones Feb. 23, 2023, 6:51 a.m. UTC | #1
On Tue, Feb 21, 2023 at 10:35:21AM +0800, Sia Jee Heng wrote:
> The cpu_resume() function is very similar for the suspend to disk and
> suspend to ram cases. Factor out the common code into restore_csr macro
> and restore_reg macro.
> 
> Signed-off-by: Sia Jee Heng <jeeheng.sia@starfivetech.com>
> ---
>  arch/riscv/include/asm/assembler.h | 62 ++++++++++++++++++++++++++++++
>  arch/riscv/kernel/suspend_entry.S  | 34 ++--------------
>  2 files changed, 65 insertions(+), 31 deletions(-)
>  create mode 100644 arch/riscv/include/asm/assembler.h
> 
> diff --git a/arch/riscv/include/asm/assembler.h b/arch/riscv/include/asm/assembler.h
> new file mode 100644
> index 000000000000..727a97735493
> --- /dev/null
> +++ b/arch/riscv/include/asm/assembler.h
> @@ -0,0 +1,62 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * Copyright (C) 2023 StarFive Technology Co., Ltd.
> + *
> + * Author: Jee Heng Sia <jeeheng.sia@starfivetech.com>
> + */
> +
> +#ifndef __ASSEMBLY__
> +#error "Only include this from assembly code"
> +#endif
> +
> +#ifndef __ASM_ASSEMBLER_H
> +#define __ASM_ASSEMBLER_H
> +
> +#include <asm/asm.h>
> +#include <asm/asm-offsets.h>
> +#include <asm/csr.h>
> +
> +/*
> + * restore_csr - restore hart's CSR value
> + */
> +	.macro restore_csr

Since there are more than one, 'restore_csrs' would be more appropriate
and s/CSR value/CSRs/

> +		REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_EPC)(a0)
> +		csrw	CSR_EPC, t0
> +		REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_STATUS)(a0)
> +		csrw	CSR_STATUS, t0
> +		REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_BADADDR)(a0)
> +		csrw	CSR_TVAL, t0
> +		REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_CAUSE)(a0)
> +		csrw	CSR_CAUSE, t0
> +	.endm
> +
> +/*
> + * restore_reg - Restore registers (except A0 and T0-T6)
> + */
> +	.macro restore_reg

restore_regs

> +		REG_L	ra, (SUSPEND_CONTEXT_REGS + PT_RA)(a0)
> +		REG_L	sp, (SUSPEND_CONTEXT_REGS + PT_SP)(a0)
> +		REG_L	gp, (SUSPEND_CONTEXT_REGS + PT_GP)(a0)
> +		REG_L	tp, (SUSPEND_CONTEXT_REGS + PT_TP)(a0)
> +		REG_L	s0, (SUSPEND_CONTEXT_REGS + PT_S0)(a0)
> +		REG_L	s1, (SUSPEND_CONTEXT_REGS + PT_S1)(a0)
> +		REG_L	a1, (SUSPEND_CONTEXT_REGS + PT_A1)(a0)
> +		REG_L	a2, (SUSPEND_CONTEXT_REGS + PT_A2)(a0)
> +		REG_L	a3, (SUSPEND_CONTEXT_REGS + PT_A3)(a0)
> +		REG_L	a4, (SUSPEND_CONTEXT_REGS + PT_A4)(a0)
> +		REG_L	a5, (SUSPEND_CONTEXT_REGS + PT_A5)(a0)
> +		REG_L	a6, (SUSPEND_CONTEXT_REGS + PT_A6)(a0)
> +		REG_L	a7, (SUSPEND_CONTEXT_REGS + PT_A7)(a0)
> +		REG_L	s2, (SUSPEND_CONTEXT_REGS + PT_S2)(a0)
> +		REG_L	s3, (SUSPEND_CONTEXT_REGS + PT_S3)(a0)
> +		REG_L	s4, (SUSPEND_CONTEXT_REGS + PT_S4)(a0)
> +		REG_L	s5, (SUSPEND_CONTEXT_REGS + PT_S5)(a0)
> +		REG_L	s6, (SUSPEND_CONTEXT_REGS + PT_S6)(a0)
> +		REG_L	s7, (SUSPEND_CONTEXT_REGS + PT_S7)(a0)
> +		REG_L	s8, (SUSPEND_CONTEXT_REGS + PT_S8)(a0)
> +		REG_L	s9, (SUSPEND_CONTEXT_REGS + PT_S9)(a0)
> +		REG_L	s10, (SUSPEND_CONTEXT_REGS + PT_S10)(a0)
> +		REG_L	s11, (SUSPEND_CONTEXT_REGS + PT_S11)(a0)
> +	.endm
> +
> +#endif	/* __ASM_ASSEMBLER_H */
> diff --git a/arch/riscv/kernel/suspend_entry.S b/arch/riscv/kernel/suspend_entry.S
> index aafcca58c19d..74a8fab8e0f6 100644
> --- a/arch/riscv/kernel/suspend_entry.S
> +++ b/arch/riscv/kernel/suspend_entry.S
> @@ -7,6 +7,7 @@
>  #include <linux/linkage.h>
>  #include <asm/asm.h>
>  #include <asm/asm-offsets.h>
> +#include <asm/assembler.h>
>  #include <asm/csr.h>
>  #include <asm/xip_fixup.h>
>  
> @@ -83,39 +84,10 @@ ENTRY(__cpu_resume_enter)
>  	add	a0, a1, zero
>  
>  	/* Restore CSRs */
> -	REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_EPC)(a0)
> -	csrw	CSR_EPC, t0
> -	REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_STATUS)(a0)
> -	csrw	CSR_STATUS, t0
> -	REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_BADADDR)(a0)
> -	csrw	CSR_TVAL, t0
> -	REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_CAUSE)(a0)
> -	csrw	CSR_CAUSE, t0
> +	restore_csr
>  
>  	/* Restore registers (except A0 and T0-T6) */
> -	REG_L	ra, (SUSPEND_CONTEXT_REGS + PT_RA)(a0)
> -	REG_L	sp, (SUSPEND_CONTEXT_REGS + PT_SP)(a0)
> -	REG_L	gp, (SUSPEND_CONTEXT_REGS + PT_GP)(a0)
> -	REG_L	tp, (SUSPEND_CONTEXT_REGS + PT_TP)(a0)
> -	REG_L	s0, (SUSPEND_CONTEXT_REGS + PT_S0)(a0)
> -	REG_L	s1, (SUSPEND_CONTEXT_REGS + PT_S1)(a0)
> -	REG_L	a1, (SUSPEND_CONTEXT_REGS + PT_A1)(a0)
> -	REG_L	a2, (SUSPEND_CONTEXT_REGS + PT_A2)(a0)
> -	REG_L	a3, (SUSPEND_CONTEXT_REGS + PT_A3)(a0)
> -	REG_L	a4, (SUSPEND_CONTEXT_REGS + PT_A4)(a0)
> -	REG_L	a5, (SUSPEND_CONTEXT_REGS + PT_A5)(a0)
> -	REG_L	a6, (SUSPEND_CONTEXT_REGS + PT_A6)(a0)
> -	REG_L	a7, (SUSPEND_CONTEXT_REGS + PT_A7)(a0)
> -	REG_L	s2, (SUSPEND_CONTEXT_REGS + PT_S2)(a0)
> -	REG_L	s3, (SUSPEND_CONTEXT_REGS + PT_S3)(a0)
> -	REG_L	s4, (SUSPEND_CONTEXT_REGS + PT_S4)(a0)
> -	REG_L	s5, (SUSPEND_CONTEXT_REGS + PT_S5)(a0)
> -	REG_L	s6, (SUSPEND_CONTEXT_REGS + PT_S6)(a0)
> -	REG_L	s7, (SUSPEND_CONTEXT_REGS + PT_S7)(a0)
> -	REG_L	s8, (SUSPEND_CONTEXT_REGS + PT_S8)(a0)
> -	REG_L	s9, (SUSPEND_CONTEXT_REGS + PT_S9)(a0)
> -	REG_L	s10, (SUSPEND_CONTEXT_REGS + PT_S10)(a0)
> -	REG_L	s11, (SUSPEND_CONTEXT_REGS + PT_S11)(a0)
> +	restore_reg
>  
>  	/* Return zero value */
>  	add	a0, zero, zero
> -- 
> 2.34.1
>

Otherwise,

Reviewed-by: Andrew Jones <ajones@ventanamicro.com>

Thanks,
drew
  
JeeHeng Sia Feb. 24, 2023, 1:33 a.m. UTC | #2
> -----Original Message-----
> From: Andrew Jones <ajones@ventanamicro.com>
> Sent: Thursday, 23 February, 2023 2:52 PM
> To: JeeHeng Sia <jeeheng.sia@starfivetech.com>
> Cc: paul.walmsley@sifive.com; palmer@dabbelt.com; aou@eecs.berkeley.edu; linux-riscv@lists.infradead.org; linux-
> kernel@vger.kernel.org; Leyfoon Tan <leyfoon.tan@starfivetech.com>; Mason Huo <mason.huo@starfivetech.com>
> Subject: Re: [PATCH v4 2/4] RISC-V: Factor out common code of __cpu_resume_enter()
> 
> On Tue, Feb 21, 2023 at 10:35:21AM +0800, Sia Jee Heng wrote:
> > The cpu_resume() function is very similar for the suspend to disk and
> > suspend to ram cases. Factor out the common code into restore_csr macro
> > and restore_reg macro.
> >
> > Signed-off-by: Sia Jee Heng <jeeheng.sia@starfivetech.com>
> > ---
> >  arch/riscv/include/asm/assembler.h | 62 ++++++++++++++++++++++++++++++
> >  arch/riscv/kernel/suspend_entry.S  | 34 ++--------------
> >  2 files changed, 65 insertions(+), 31 deletions(-)
> >  create mode 100644 arch/riscv/include/asm/assembler.h
> >
> > diff --git a/arch/riscv/include/asm/assembler.h b/arch/riscv/include/asm/assembler.h
> > new file mode 100644
> > index 000000000000..727a97735493
> > --- /dev/null
> > +++ b/arch/riscv/include/asm/assembler.h
> > @@ -0,0 +1,62 @@
> > +/* SPDX-License-Identifier: GPL-2.0-only */
> > +/*
> > + * Copyright (C) 2023 StarFive Technology Co., Ltd.
> > + *
> > + * Author: Jee Heng Sia <jeeheng.sia@starfivetech.com>
> > + */
> > +
> > +#ifndef __ASSEMBLY__
> > +#error "Only include this from assembly code"
> > +#endif
> > +
> > +#ifndef __ASM_ASSEMBLER_H
> > +#define __ASM_ASSEMBLER_H
> > +
> > +#include <asm/asm.h>
> > +#include <asm/asm-offsets.h>
> > +#include <asm/csr.h>
> > +
> > +/*
> > + * restore_csr - restore hart's CSR value
> > + */
> > +	.macro restore_csr
> 
> Since there are more than one, 'restore_csrs' would be more appropriate
> and s/CSR value/CSRs/
> 
> > +		REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_EPC)(a0)
> > +		csrw	CSR_EPC, t0
> > +		REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_STATUS)(a0)
> > +		csrw	CSR_STATUS, t0
> > +		REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_BADADDR)(a0)
> > +		csrw	CSR_TVAL, t0
> > +		REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_CAUSE)(a0)
> > +		csrw	CSR_CAUSE, t0
> > +	.endm
> > +
> > +/*
> > + * restore_reg - Restore registers (except A0 and T0-T6)
> > + */
> > +	.macro restore_reg
> 
> restore_regs
> 
> > +		REG_L	ra, (SUSPEND_CONTEXT_REGS + PT_RA)(a0)
> > +		REG_L	sp, (SUSPEND_CONTEXT_REGS + PT_SP)(a0)
> > +		REG_L	gp, (SUSPEND_CONTEXT_REGS + PT_GP)(a0)
> > +		REG_L	tp, (SUSPEND_CONTEXT_REGS + PT_TP)(a0)
> > +		REG_L	s0, (SUSPEND_CONTEXT_REGS + PT_S0)(a0)
> > +		REG_L	s1, (SUSPEND_CONTEXT_REGS + PT_S1)(a0)
> > +		REG_L	a1, (SUSPEND_CONTEXT_REGS + PT_A1)(a0)
> > +		REG_L	a2, (SUSPEND_CONTEXT_REGS + PT_A2)(a0)
> > +		REG_L	a3, (SUSPEND_CONTEXT_REGS + PT_A3)(a0)
> > +		REG_L	a4, (SUSPEND_CONTEXT_REGS + PT_A4)(a0)
> > +		REG_L	a5, (SUSPEND_CONTEXT_REGS + PT_A5)(a0)
> > +		REG_L	a6, (SUSPEND_CONTEXT_REGS + PT_A6)(a0)
> > +		REG_L	a7, (SUSPEND_CONTEXT_REGS + PT_A7)(a0)
> > +		REG_L	s2, (SUSPEND_CONTEXT_REGS + PT_S2)(a0)
> > +		REG_L	s3, (SUSPEND_CONTEXT_REGS + PT_S3)(a0)
> > +		REG_L	s4, (SUSPEND_CONTEXT_REGS + PT_S4)(a0)
> > +		REG_L	s5, (SUSPEND_CONTEXT_REGS + PT_S5)(a0)
> > +		REG_L	s6, (SUSPEND_CONTEXT_REGS + PT_S6)(a0)
> > +		REG_L	s7, (SUSPEND_CONTEXT_REGS + PT_S7)(a0)
> > +		REG_L	s8, (SUSPEND_CONTEXT_REGS + PT_S8)(a0)
> > +		REG_L	s9, (SUSPEND_CONTEXT_REGS + PT_S9)(a0)
> > +		REG_L	s10, (SUSPEND_CONTEXT_REGS + PT_S10)(a0)
> > +		REG_L	s11, (SUSPEND_CONTEXT_REGS + PT_S11)(a0)
> > +	.endm
> > +
> > +#endif	/* __ASM_ASSEMBLER_H */
> > diff --git a/arch/riscv/kernel/suspend_entry.S b/arch/riscv/kernel/suspend_entry.S
> > index aafcca58c19d..74a8fab8e0f6 100644
> > --- a/arch/riscv/kernel/suspend_entry.S
> > +++ b/arch/riscv/kernel/suspend_entry.S
> > @@ -7,6 +7,7 @@
> >  #include <linux/linkage.h>
> >  #include <asm/asm.h>
> >  #include <asm/asm-offsets.h>
> > +#include <asm/assembler.h>
> >  #include <asm/csr.h>
> >  #include <asm/xip_fixup.h>
> >
> > @@ -83,39 +84,10 @@ ENTRY(__cpu_resume_enter)
> >  	add	a0, a1, zero
> >
> >  	/* Restore CSRs */
> > -	REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_EPC)(a0)
> > -	csrw	CSR_EPC, t0
> > -	REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_STATUS)(a0)
> > -	csrw	CSR_STATUS, t0
> > -	REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_BADADDR)(a0)
> > -	csrw	CSR_TVAL, t0
> > -	REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_CAUSE)(a0)
> > -	csrw	CSR_CAUSE, t0
> > +	restore_csr
> >
> >  	/* Restore registers (except A0 and T0-T6) */
> > -	REG_L	ra, (SUSPEND_CONTEXT_REGS + PT_RA)(a0)
> > -	REG_L	sp, (SUSPEND_CONTEXT_REGS + PT_SP)(a0)
> > -	REG_L	gp, (SUSPEND_CONTEXT_REGS + PT_GP)(a0)
> > -	REG_L	tp, (SUSPEND_CONTEXT_REGS + PT_TP)(a0)
> > -	REG_L	s0, (SUSPEND_CONTEXT_REGS + PT_S0)(a0)
> > -	REG_L	s1, (SUSPEND_CONTEXT_REGS + PT_S1)(a0)
> > -	REG_L	a1, (SUSPEND_CONTEXT_REGS + PT_A1)(a0)
> > -	REG_L	a2, (SUSPEND_CONTEXT_REGS + PT_A2)(a0)
> > -	REG_L	a3, (SUSPEND_CONTEXT_REGS + PT_A3)(a0)
> > -	REG_L	a4, (SUSPEND_CONTEXT_REGS + PT_A4)(a0)
> > -	REG_L	a5, (SUSPEND_CONTEXT_REGS + PT_A5)(a0)
> > -	REG_L	a6, (SUSPEND_CONTEXT_REGS + PT_A6)(a0)
> > -	REG_L	a7, (SUSPEND_CONTEXT_REGS + PT_A7)(a0)
> > -	REG_L	s2, (SUSPEND_CONTEXT_REGS + PT_S2)(a0)
> > -	REG_L	s3, (SUSPEND_CONTEXT_REGS + PT_S3)(a0)
> > -	REG_L	s4, (SUSPEND_CONTEXT_REGS + PT_S4)(a0)
> > -	REG_L	s5, (SUSPEND_CONTEXT_REGS + PT_S5)(a0)
> > -	REG_L	s6, (SUSPEND_CONTEXT_REGS + PT_S6)(a0)
> > -	REG_L	s7, (SUSPEND_CONTEXT_REGS + PT_S7)(a0)
> > -	REG_L	s8, (SUSPEND_CONTEXT_REGS + PT_S8)(a0)
> > -	REG_L	s9, (SUSPEND_CONTEXT_REGS + PT_S9)(a0)
> > -	REG_L	s10, (SUSPEND_CONTEXT_REGS + PT_S10)(a0)
> > -	REG_L	s11, (SUSPEND_CONTEXT_REGS + PT_S11)(a0)
> > +	restore_reg
> >
> >  	/* Return zero value */
> >  	add	a0, zero, zero
> > --
> > 2.34.1
> >
> 
> Otherwise,
> 
> Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
noted with thanks
> 
> Thanks,
> drew
  
Alexandre Ghiti Feb. 24, 2023, 10:19 a.m. UTC | #3
Hi Sia,

On 2/21/23 03:35, Sia Jee Heng wrote:
> The cpu_resume() function is very similar for the suspend to disk and
> suspend to ram cases. Factor out the common code into restore_csr macro
> and restore_reg macro.
>
> Signed-off-by: Sia Jee Heng <jeeheng.sia@starfivetech.com>
> ---
>   arch/riscv/include/asm/assembler.h | 62 ++++++++++++++++++++++++++++++
>   arch/riscv/kernel/suspend_entry.S  | 34 ++--------------
>   2 files changed, 65 insertions(+), 31 deletions(-)
>   create mode 100644 arch/riscv/include/asm/assembler.h
>
> diff --git a/arch/riscv/include/asm/assembler.h b/arch/riscv/include/asm/assembler.h
> new file mode 100644
> index 000000000000..727a97735493
> --- /dev/null
> +++ b/arch/riscv/include/asm/assembler.h
> @@ -0,0 +1,62 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * Copyright (C) 2023 StarFive Technology Co., Ltd.
> + *
> + * Author: Jee Heng Sia <jeeheng.sia@starfivetech.com>
> + */
> +
> +#ifndef __ASSEMBLY__
> +#error "Only include this from assembly code"
> +#endif
> +
> +#ifndef __ASM_ASSEMBLER_H
> +#define __ASM_ASSEMBLER_H
> +
> +#include <asm/asm.h>
> +#include <asm/asm-offsets.h>
> +#include <asm/csr.h>
> +
> +/*
> + * restore_csr - restore hart's CSR value
> + */
> +	.macro restore_csr
> +		REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_EPC)(a0)
> +		csrw	CSR_EPC, t0
> +		REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_STATUS)(a0)
> +		csrw	CSR_STATUS, t0
> +		REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_BADADDR)(a0)
> +		csrw	CSR_TVAL, t0
> +		REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_CAUSE)(a0)
> +		csrw	CSR_CAUSE, t0
> +	.endm
> +
> +/*
> + * restore_reg - Restore registers (except A0 and T0-T6)
> + */
> +	.macro restore_reg
> +		REG_L	ra, (SUSPEND_CONTEXT_REGS + PT_RA)(a0)
> +		REG_L	sp, (SUSPEND_CONTEXT_REGS + PT_SP)(a0)
> +		REG_L	gp, (SUSPEND_CONTEXT_REGS + PT_GP)(a0)
> +		REG_L	tp, (SUSPEND_CONTEXT_REGS + PT_TP)(a0)
> +		REG_L	s0, (SUSPEND_CONTEXT_REGS + PT_S0)(a0)
> +		REG_L	s1, (SUSPEND_CONTEXT_REGS + PT_S1)(a0)
> +		REG_L	a1, (SUSPEND_CONTEXT_REGS + PT_A1)(a0)
> +		REG_L	a2, (SUSPEND_CONTEXT_REGS + PT_A2)(a0)
> +		REG_L	a3, (SUSPEND_CONTEXT_REGS + PT_A3)(a0)
> +		REG_L	a4, (SUSPEND_CONTEXT_REGS + PT_A4)(a0)
> +		REG_L	a5, (SUSPEND_CONTEXT_REGS + PT_A5)(a0)
> +		REG_L	a6, (SUSPEND_CONTEXT_REGS + PT_A6)(a0)
> +		REG_L	a7, (SUSPEND_CONTEXT_REGS + PT_A7)(a0)
> +		REG_L	s2, (SUSPEND_CONTEXT_REGS + PT_S2)(a0)
> +		REG_L	s3, (SUSPEND_CONTEXT_REGS + PT_S3)(a0)
> +		REG_L	s4, (SUSPEND_CONTEXT_REGS + PT_S4)(a0)
> +		REG_L	s5, (SUSPEND_CONTEXT_REGS + PT_S5)(a0)
> +		REG_L	s6, (SUSPEND_CONTEXT_REGS + PT_S6)(a0)
> +		REG_L	s7, (SUSPEND_CONTEXT_REGS + PT_S7)(a0)
> +		REG_L	s8, (SUSPEND_CONTEXT_REGS + PT_S8)(a0)
> +		REG_L	s9, (SUSPEND_CONTEXT_REGS + PT_S9)(a0)
> +		REG_L	s10, (SUSPEND_CONTEXT_REGS + PT_S10)(a0)
> +		REG_L	s11, (SUSPEND_CONTEXT_REGS + PT_S11)(a0)
> +	.endm
> +
> +#endif	/* __ASM_ASSEMBLER_H */


You introduce assembler.h which in the future may contain other assembly 
functions not related to suspend: I'd rename those macros so that we 
know they are suspend related, something like 
suspend_restore_regs/suspend_restore_csrs.

And instead of (SUSPEND_CONTEXT_REGS + PT_XXX) you could introduce 
SUSPEND_CONTEXT_REGS_PT_XXX in asm-offsets.c?


> diff --git a/arch/riscv/kernel/suspend_entry.S b/arch/riscv/kernel/suspend_entry.S
> index aafcca58c19d..74a8fab8e0f6 100644
> --- a/arch/riscv/kernel/suspend_entry.S
> +++ b/arch/riscv/kernel/suspend_entry.S
> @@ -7,6 +7,7 @@
>   #include <linux/linkage.h>
>   #include <asm/asm.h>
>   #include <asm/asm-offsets.h>
> +#include <asm/assembler.h>
>   #include <asm/csr.h>
>   #include <asm/xip_fixup.h>
>   
> @@ -83,39 +84,10 @@ ENTRY(__cpu_resume_enter)
>   	add	a0, a1, zero
>   
>   	/* Restore CSRs */
> -	REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_EPC)(a0)
> -	csrw	CSR_EPC, t0
> -	REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_STATUS)(a0)
> -	csrw	CSR_STATUS, t0
> -	REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_BADADDR)(a0)
> -	csrw	CSR_TVAL, t0
> -	REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_CAUSE)(a0)
> -	csrw	CSR_CAUSE, t0
> +	restore_csr
>   
>   	/* Restore registers (except A0 and T0-T6) */
> -	REG_L	ra, (SUSPEND_CONTEXT_REGS + PT_RA)(a0)
> -	REG_L	sp, (SUSPEND_CONTEXT_REGS + PT_SP)(a0)
> -	REG_L	gp, (SUSPEND_CONTEXT_REGS + PT_GP)(a0)
> -	REG_L	tp, (SUSPEND_CONTEXT_REGS + PT_TP)(a0)
> -	REG_L	s0, (SUSPEND_CONTEXT_REGS + PT_S0)(a0)
> -	REG_L	s1, (SUSPEND_CONTEXT_REGS + PT_S1)(a0)
> -	REG_L	a1, (SUSPEND_CONTEXT_REGS + PT_A1)(a0)
> -	REG_L	a2, (SUSPEND_CONTEXT_REGS + PT_A2)(a0)
> -	REG_L	a3, (SUSPEND_CONTEXT_REGS + PT_A3)(a0)
> -	REG_L	a4, (SUSPEND_CONTEXT_REGS + PT_A4)(a0)
> -	REG_L	a5, (SUSPEND_CONTEXT_REGS + PT_A5)(a0)
> -	REG_L	a6, (SUSPEND_CONTEXT_REGS + PT_A6)(a0)
> -	REG_L	a7, (SUSPEND_CONTEXT_REGS + PT_A7)(a0)
> -	REG_L	s2, (SUSPEND_CONTEXT_REGS + PT_S2)(a0)
> -	REG_L	s3, (SUSPEND_CONTEXT_REGS + PT_S3)(a0)
> -	REG_L	s4, (SUSPEND_CONTEXT_REGS + PT_S4)(a0)
> -	REG_L	s5, (SUSPEND_CONTEXT_REGS + PT_S5)(a0)
> -	REG_L	s6, (SUSPEND_CONTEXT_REGS + PT_S6)(a0)
> -	REG_L	s7, (SUSPEND_CONTEXT_REGS + PT_S7)(a0)
> -	REG_L	s8, (SUSPEND_CONTEXT_REGS + PT_S8)(a0)
> -	REG_L	s9, (SUSPEND_CONTEXT_REGS + PT_S9)(a0)
> -	REG_L	s10, (SUSPEND_CONTEXT_REGS + PT_S10)(a0)
> -	REG_L	s11, (SUSPEND_CONTEXT_REGS + PT_S11)(a0)
> +	restore_reg
>   
>   	/* Return zero value */
>   	add	a0, zero, zero
  
JeeHeng Sia Feb. 27, 2023, 2:21 a.m. UTC | #4
> -----Original Message-----
> From: Alexandre Ghiti <alex@ghiti.fr>
> Sent: Friday, 24 February, 2023 6:19 PM
> To: JeeHeng Sia <jeeheng.sia@starfivetech.com>; paul.walmsley@sifive.com; palmer@dabbelt.com; aou@eecs.berkeley.edu
> Cc: linux-riscv@lists.infradead.org; linux-kernel@vger.kernel.org; Leyfoon Tan <leyfoon.tan@starfivetech.com>; Mason Huo
> <mason.huo@starfivetech.com>
> Subject: Re: [PATCH v4 2/4] RISC-V: Factor out common code of __cpu_resume_enter()
> 
> Hi Sia,
> 
> On 2/21/23 03:35, Sia Jee Heng wrote:
> > The cpu_resume() function is very similar for the suspend to disk and
> > suspend to ram cases. Factor out the common code into restore_csr macro
> > and restore_reg macro.
> >
> > Signed-off-by: Sia Jee Heng <jeeheng.sia@starfivetech.com>
> > ---
> >   arch/riscv/include/asm/assembler.h | 62 ++++++++++++++++++++++++++++++
> >   arch/riscv/kernel/suspend_entry.S  | 34 ++--------------
> >   2 files changed, 65 insertions(+), 31 deletions(-)
> >   create mode 100644 arch/riscv/include/asm/assembler.h
> >
> > diff --git a/arch/riscv/include/asm/assembler.h b/arch/riscv/include/asm/assembler.h
> > new file mode 100644
> > index 000000000000..727a97735493
> > --- /dev/null
> > +++ b/arch/riscv/include/asm/assembler.h
> > @@ -0,0 +1,62 @@
> > +/* SPDX-License-Identifier: GPL-2.0-only */
> > +/*
> > + * Copyright (C) 2023 StarFive Technology Co., Ltd.
> > + *
> > + * Author: Jee Heng Sia <jeeheng.sia@starfivetech.com>
> > + */
> > +
> > +#ifndef __ASSEMBLY__
> > +#error "Only include this from assembly code"
> > +#endif
> > +
> > +#ifndef __ASM_ASSEMBLER_H
> > +#define __ASM_ASSEMBLER_H
> > +
> > +#include <asm/asm.h>
> > +#include <asm/asm-offsets.h>
> > +#include <asm/csr.h>
> > +
> > +/*
> > + * restore_csr - restore hart's CSR value
> > + */
> > +	.macro restore_csr
> > +		REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_EPC)(a0)
> > +		csrw	CSR_EPC, t0
> > +		REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_STATUS)(a0)
> > +		csrw	CSR_STATUS, t0
> > +		REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_BADADDR)(a0)
> > +		csrw	CSR_TVAL, t0
> > +		REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_CAUSE)(a0)
> > +		csrw	CSR_CAUSE, t0
> > +	.endm
> > +
> > +/*
> > + * restore_reg - Restore registers (except A0 and T0-T6)
> > + */
> > +	.macro restore_reg
> > +		REG_L	ra, (SUSPEND_CONTEXT_REGS + PT_RA)(a0)
> > +		REG_L	sp, (SUSPEND_CONTEXT_REGS + PT_SP)(a0)
> > +		REG_L	gp, (SUSPEND_CONTEXT_REGS + PT_GP)(a0)
> > +		REG_L	tp, (SUSPEND_CONTEXT_REGS + PT_TP)(a0)
> > +		REG_L	s0, (SUSPEND_CONTEXT_REGS + PT_S0)(a0)
> > +		REG_L	s1, (SUSPEND_CONTEXT_REGS + PT_S1)(a0)
> > +		REG_L	a1, (SUSPEND_CONTEXT_REGS + PT_A1)(a0)
> > +		REG_L	a2, (SUSPEND_CONTEXT_REGS + PT_A2)(a0)
> > +		REG_L	a3, (SUSPEND_CONTEXT_REGS + PT_A3)(a0)
> > +		REG_L	a4, (SUSPEND_CONTEXT_REGS + PT_A4)(a0)
> > +		REG_L	a5, (SUSPEND_CONTEXT_REGS + PT_A5)(a0)
> > +		REG_L	a6, (SUSPEND_CONTEXT_REGS + PT_A6)(a0)
> > +		REG_L	a7, (SUSPEND_CONTEXT_REGS + PT_A7)(a0)
> > +		REG_L	s2, (SUSPEND_CONTEXT_REGS + PT_S2)(a0)
> > +		REG_L	s3, (SUSPEND_CONTEXT_REGS + PT_S3)(a0)
> > +		REG_L	s4, (SUSPEND_CONTEXT_REGS + PT_S4)(a0)
> > +		REG_L	s5, (SUSPEND_CONTEXT_REGS + PT_S5)(a0)
> > +		REG_L	s6, (SUSPEND_CONTEXT_REGS + PT_S6)(a0)
> > +		REG_L	s7, (SUSPEND_CONTEXT_REGS + PT_S7)(a0)
> > +		REG_L	s8, (SUSPEND_CONTEXT_REGS + PT_S8)(a0)
> > +		REG_L	s9, (SUSPEND_CONTEXT_REGS + PT_S9)(a0)
> > +		REG_L	s10, (SUSPEND_CONTEXT_REGS + PT_S10)(a0)
> > +		REG_L	s11, (SUSPEND_CONTEXT_REGS + PT_S11)(a0)
> > +	.endm
> > +
> > +#endif	/* __ASM_ASSEMBLER_H */
> 
> 
> You introduce assembler.h which in the future may contain other assembly
> functions not related to suspend: I'd rename those macros so that we
> know they are suspend related, something like
> suspend_restore_regs/suspend_restore_csrs.
Sure, these can be done.
> 
> And instead of (SUSPEND_CONTEXT_REGS + PT_XXX) you could introduce
> SUSPEND_CONTEXT_REGS_PT_XXX in asm-offsets.c?
There are already PT_XXX defined in the asm-offset.c, we should not create another set of SUSPEND_CONTEXT_REGS_PT_XXX because we can just re-use the definition instead of duplicate another set of offset which are doing the same thing. So, I would rather stick with the current definition.
	DEFINE(PT_SIZE, sizeof(struct pt_regs));
	OFFSET(PT_EPC, pt_regs, epc);
	OFFSET(PT_RA, pt_regs, ra);
	OFFSET(PT_FP, pt_regs, s0);
	OFFSET(PT_S0, pt_regs, s0);
	OFFSET(PT_S1, pt_regs, s1);
	OFFSET(PT_S2, pt_regs, s2);
> 
> 
> > diff --git a/arch/riscv/kernel/suspend_entry.S b/arch/riscv/kernel/suspend_entry.S
> > index aafcca58c19d..74a8fab8e0f6 100644
> > --- a/arch/riscv/kernel/suspend_entry.S
> > +++ b/arch/riscv/kernel/suspend_entry.S
> > @@ -7,6 +7,7 @@
> >   #include <linux/linkage.h>
> >   #include <asm/asm.h>
> >   #include <asm/asm-offsets.h>
> > +#include <asm/assembler.h>
> >   #include <asm/csr.h>
> >   #include <asm/xip_fixup.h>
> >
> > @@ -83,39 +84,10 @@ ENTRY(__cpu_resume_enter)
> >   	add	a0, a1, zero
> >
> >   	/* Restore CSRs */
> > -	REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_EPC)(a0)
> > -	csrw	CSR_EPC, t0
> > -	REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_STATUS)(a0)
> > -	csrw	CSR_STATUS, t0
> > -	REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_BADADDR)(a0)
> > -	csrw	CSR_TVAL, t0
> > -	REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_CAUSE)(a0)
> > -	csrw	CSR_CAUSE, t0
> > +	restore_csr
> >
> >   	/* Restore registers (except A0 and T0-T6) */
> > -	REG_L	ra, (SUSPEND_CONTEXT_REGS + PT_RA)(a0)
> > -	REG_L	sp, (SUSPEND_CONTEXT_REGS + PT_SP)(a0)
> > -	REG_L	gp, (SUSPEND_CONTEXT_REGS + PT_GP)(a0)
> > -	REG_L	tp, (SUSPEND_CONTEXT_REGS + PT_TP)(a0)
> > -	REG_L	s0, (SUSPEND_CONTEXT_REGS + PT_S0)(a0)
> > -	REG_L	s1, (SUSPEND_CONTEXT_REGS + PT_S1)(a0)
> > -	REG_L	a1, (SUSPEND_CONTEXT_REGS + PT_A1)(a0)
> > -	REG_L	a2, (SUSPEND_CONTEXT_REGS + PT_A2)(a0)
> > -	REG_L	a3, (SUSPEND_CONTEXT_REGS + PT_A3)(a0)
> > -	REG_L	a4, (SUSPEND_CONTEXT_REGS + PT_A4)(a0)
> > -	REG_L	a5, (SUSPEND_CONTEXT_REGS + PT_A5)(a0)
> > -	REG_L	a6, (SUSPEND_CONTEXT_REGS + PT_A6)(a0)
> > -	REG_L	a7, (SUSPEND_CONTEXT_REGS + PT_A7)(a0)
> > -	REG_L	s2, (SUSPEND_CONTEXT_REGS + PT_S2)(a0)
> > -	REG_L	s3, (SUSPEND_CONTEXT_REGS + PT_S3)(a0)
> > -	REG_L	s4, (SUSPEND_CONTEXT_REGS + PT_S4)(a0)
> > -	REG_L	s5, (SUSPEND_CONTEXT_REGS + PT_S5)(a0)
> > -	REG_L	s6, (SUSPEND_CONTEXT_REGS + PT_S6)(a0)
> > -	REG_L	s7, (SUSPEND_CONTEXT_REGS + PT_S7)(a0)
> > -	REG_L	s8, (SUSPEND_CONTEXT_REGS + PT_S8)(a0)
> > -	REG_L	s9, (SUSPEND_CONTEXT_REGS + PT_S9)(a0)
> > -	REG_L	s10, (SUSPEND_CONTEXT_REGS + PT_S10)(a0)
> > -	REG_L	s11, (SUSPEND_CONTEXT_REGS + PT_S11)(a0)
> > +	restore_reg
> >
> >   	/* Return zero value */
> >   	add	a0, zero, zero
  

Patch

diff --git a/arch/riscv/include/asm/assembler.h b/arch/riscv/include/asm/assembler.h
new file mode 100644
index 000000000000..727a97735493
--- /dev/null
+++ b/arch/riscv/include/asm/assembler.h
@@ -0,0 +1,62 @@ 
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2023 StarFive Technology Co., Ltd.
+ *
+ * Author: Jee Heng Sia <jeeheng.sia@starfivetech.com>
+ */
+
+#ifndef __ASSEMBLY__
+#error "Only include this from assembly code"
+#endif
+
+#ifndef __ASM_ASSEMBLER_H
+#define __ASM_ASSEMBLER_H
+
+#include <asm/asm.h>
+#include <asm/asm-offsets.h>
+#include <asm/csr.h>
+
+/*
+ * restore_csr - restore hart's CSR value
+ */
+	.macro restore_csr
+		REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_EPC)(a0)
+		csrw	CSR_EPC, t0
+		REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_STATUS)(a0)
+		csrw	CSR_STATUS, t0
+		REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_BADADDR)(a0)
+		csrw	CSR_TVAL, t0
+		REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_CAUSE)(a0)
+		csrw	CSR_CAUSE, t0
+	.endm
+
+/*
+ * restore_reg - Restore registers (except A0 and T0-T6)
+ */
+	.macro restore_reg
+		REG_L	ra, (SUSPEND_CONTEXT_REGS + PT_RA)(a0)
+		REG_L	sp, (SUSPEND_CONTEXT_REGS + PT_SP)(a0)
+		REG_L	gp, (SUSPEND_CONTEXT_REGS + PT_GP)(a0)
+		REG_L	tp, (SUSPEND_CONTEXT_REGS + PT_TP)(a0)
+		REG_L	s0, (SUSPEND_CONTEXT_REGS + PT_S0)(a0)
+		REG_L	s1, (SUSPEND_CONTEXT_REGS + PT_S1)(a0)
+		REG_L	a1, (SUSPEND_CONTEXT_REGS + PT_A1)(a0)
+		REG_L	a2, (SUSPEND_CONTEXT_REGS + PT_A2)(a0)
+		REG_L	a3, (SUSPEND_CONTEXT_REGS + PT_A3)(a0)
+		REG_L	a4, (SUSPEND_CONTEXT_REGS + PT_A4)(a0)
+		REG_L	a5, (SUSPEND_CONTEXT_REGS + PT_A5)(a0)
+		REG_L	a6, (SUSPEND_CONTEXT_REGS + PT_A6)(a0)
+		REG_L	a7, (SUSPEND_CONTEXT_REGS + PT_A7)(a0)
+		REG_L	s2, (SUSPEND_CONTEXT_REGS + PT_S2)(a0)
+		REG_L	s3, (SUSPEND_CONTEXT_REGS + PT_S3)(a0)
+		REG_L	s4, (SUSPEND_CONTEXT_REGS + PT_S4)(a0)
+		REG_L	s5, (SUSPEND_CONTEXT_REGS + PT_S5)(a0)
+		REG_L	s6, (SUSPEND_CONTEXT_REGS + PT_S6)(a0)
+		REG_L	s7, (SUSPEND_CONTEXT_REGS + PT_S7)(a0)
+		REG_L	s8, (SUSPEND_CONTEXT_REGS + PT_S8)(a0)
+		REG_L	s9, (SUSPEND_CONTEXT_REGS + PT_S9)(a0)
+		REG_L	s10, (SUSPEND_CONTEXT_REGS + PT_S10)(a0)
+		REG_L	s11, (SUSPEND_CONTEXT_REGS + PT_S11)(a0)
+	.endm
+
+#endif	/* __ASM_ASSEMBLER_H */
diff --git a/arch/riscv/kernel/suspend_entry.S b/arch/riscv/kernel/suspend_entry.S
index aafcca58c19d..74a8fab8e0f6 100644
--- a/arch/riscv/kernel/suspend_entry.S
+++ b/arch/riscv/kernel/suspend_entry.S
@@ -7,6 +7,7 @@ 
 #include <linux/linkage.h>
 #include <asm/asm.h>
 #include <asm/asm-offsets.h>
+#include <asm/assembler.h>
 #include <asm/csr.h>
 #include <asm/xip_fixup.h>
 
@@ -83,39 +84,10 @@  ENTRY(__cpu_resume_enter)
 	add	a0, a1, zero
 
 	/* Restore CSRs */
-	REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_EPC)(a0)
-	csrw	CSR_EPC, t0
-	REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_STATUS)(a0)
-	csrw	CSR_STATUS, t0
-	REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_BADADDR)(a0)
-	csrw	CSR_TVAL, t0
-	REG_L	t0, (SUSPEND_CONTEXT_REGS + PT_CAUSE)(a0)
-	csrw	CSR_CAUSE, t0
+	restore_csr
 
 	/* Restore registers (except A0 and T0-T6) */
-	REG_L	ra, (SUSPEND_CONTEXT_REGS + PT_RA)(a0)
-	REG_L	sp, (SUSPEND_CONTEXT_REGS + PT_SP)(a0)
-	REG_L	gp, (SUSPEND_CONTEXT_REGS + PT_GP)(a0)
-	REG_L	tp, (SUSPEND_CONTEXT_REGS + PT_TP)(a0)
-	REG_L	s0, (SUSPEND_CONTEXT_REGS + PT_S0)(a0)
-	REG_L	s1, (SUSPEND_CONTEXT_REGS + PT_S1)(a0)
-	REG_L	a1, (SUSPEND_CONTEXT_REGS + PT_A1)(a0)
-	REG_L	a2, (SUSPEND_CONTEXT_REGS + PT_A2)(a0)
-	REG_L	a3, (SUSPEND_CONTEXT_REGS + PT_A3)(a0)
-	REG_L	a4, (SUSPEND_CONTEXT_REGS + PT_A4)(a0)
-	REG_L	a5, (SUSPEND_CONTEXT_REGS + PT_A5)(a0)
-	REG_L	a6, (SUSPEND_CONTEXT_REGS + PT_A6)(a0)
-	REG_L	a7, (SUSPEND_CONTEXT_REGS + PT_A7)(a0)
-	REG_L	s2, (SUSPEND_CONTEXT_REGS + PT_S2)(a0)
-	REG_L	s3, (SUSPEND_CONTEXT_REGS + PT_S3)(a0)
-	REG_L	s4, (SUSPEND_CONTEXT_REGS + PT_S4)(a0)
-	REG_L	s5, (SUSPEND_CONTEXT_REGS + PT_S5)(a0)
-	REG_L	s6, (SUSPEND_CONTEXT_REGS + PT_S6)(a0)
-	REG_L	s7, (SUSPEND_CONTEXT_REGS + PT_S7)(a0)
-	REG_L	s8, (SUSPEND_CONTEXT_REGS + PT_S8)(a0)
-	REG_L	s9, (SUSPEND_CONTEXT_REGS + PT_S9)(a0)
-	REG_L	s10, (SUSPEND_CONTEXT_REGS + PT_S10)(a0)
-	REG_L	s11, (SUSPEND_CONTEXT_REGS + PT_S11)(a0)
+	restore_reg
 
 	/* Return zero value */
 	add	a0, zero, zero