[PATCH] firware: optimize the exception exit code

[Anup Patel]

> -----Original Message-----
> From: wxjstz at 126.com <wxjstz at 126.com>
> Sent: 30 March 2021 17:38
> To: opensbi at lists.infradead.org
> Cc: Anup Patel <Anup.Patel at wdc.com>; Xiang W <wxjstz at 126.com>
> Subject: [PATCH] firware: optimize the exception exit code
> 
> From: Xiang W <wxjstz at 126.com>
> 
> There are two copies of the same abnormal exit code, this patch deletes one
> 
> Signed-off-by: Xiang W <wxjstz at 126.com>

Looks good to me.

Reviewed-by: Anup Patel <anup.patel at wdc.com>

Regards,
Anup

> ---
>  firmware/fw_base.S     | 24 ++----------------------
>  include/sbi/sbi_trap.h |  2 +-
>  lib/sbi/sbi_trap.c     |  5 +++--
>  3 files changed, 6 insertions(+), 25 deletions(-)
> 
> diff --git a/firmware/fw_base.S b/firmware/fw_base.S index
> 2ce3851..c897ed0 100644
> --- a/firmware/fw_base.S
> +++ b/firmware/fw_base.S
> @@ -711,6 +711,7 @@ fw_platform_init:
>  	.section .entry, "ax", %progbits
>  	.align 3
>  	.globl _trap_handler
> +	.globl _trap_exit
>  _trap_handler:
>  	TRAP_SAVE_AND_SETUP_SP_T0
> 
> @@ -720,17 +721,6 @@ _trap_handler:
> 
>  	TRAP_CALL_C_ROUTINE
> 
> -	TRAP_RESTORE_GENERAL_REGS_EXCEPT_SP_T0
> -
> -	TRAP_RESTORE_MEPC_MSTATUS 0
> -
> -	TRAP_RESTORE_SP_T0
> -
> -	mret
> -
> -	.section .entry, "ax", %progbits
> -	.align 3
> -	.globl _trap_exit
>  _trap_exit:
>  	add	sp, a0, zero
> 
> @@ -746,6 +736,7 @@ _trap_exit:
>  	.section .entry, "ax", %progbits
>  	.align 3
>  	.globl _trap_handler_rv32_hyp
> +	.globl _trap_exit_rv32_hyp
>  _trap_handler_rv32_hyp:
>  	TRAP_SAVE_AND_SETUP_SP_T0
> 
> @@ -755,17 +746,6 @@ _trap_handler_rv32_hyp:
> 
>  	TRAP_CALL_C_ROUTINE
> 
> -	TRAP_RESTORE_GENERAL_REGS_EXCEPT_SP_T0
> -
> -	TRAP_RESTORE_MEPC_MSTATUS 1
> -
> -	TRAP_RESTORE_SP_T0
> -
> -	mret
> -
> -	.section .entry, "ax", %progbits
> -	.align 3
> -	.globl _trap_exit_rv32_hyp
>  _trap_exit_rv32_hyp:
>  	add	sp, a0, zero
> 
> diff --git a/include/sbi/sbi_trap.h b/include/sbi/sbi_trap.h index
> 070d000..0ed10df 100644
> --- a/include/sbi/sbi_trap.h
> +++ b/include/sbi/sbi_trap.h
> @@ -205,7 +205,7 @@ struct sbi_trap_info {  int sbi_trap_redirect(struct
> sbi_trap_regs *regs,
>  		      struct sbi_trap_info *trap);
> 
> -void sbi_trap_handler(struct sbi_trap_regs *regs);
> +struct sbi_trap_regs* sbi_trap_handler(struct sbi_trap_regs *regs);
> 
>  void __noreturn sbi_trap_exit(const struct sbi_trap_regs *regs);
> 
> diff --git a/lib/sbi/sbi_trap.c b/lib/sbi/sbi_trap.c index b7349d2..07d5acb
> 100644
> --- a/lib/sbi/sbi_trap.c
> +++ b/lib/sbi/sbi_trap.c
> @@ -210,7 +210,7 @@ int sbi_trap_redirect(struct sbi_trap_regs *regs,
>   *
>   * @param regs pointer to register state
>   */
> -void sbi_trap_handler(struct sbi_trap_regs *regs)
> +struct sbi_trap_regs* sbi_trap_handler(struct sbi_trap_regs *regs)
>  {
>  	int rc = SBI_ENOTSUPP;
>  	const char *msg = "trap handler failed"; @@ -236,7 +236,7 @@ void
> sbi_trap_handler(struct sbi_trap_regs *regs)
>  			msg = "unhandled external interrupt";
>  			goto trap_error;
>  		};
> -		return;
> +		return regs;
>  	}
> 
>  	switch (mcause) {
> @@ -271,6 +271,7 @@ void sbi_trap_handler(struct sbi_trap_regs *regs)
>  trap_error:
>  	if (rc)
>  		sbi_trap_error(msg, rc, mcause, mtval, mtval2, mtinst, regs);
> +	return regs;
>  }
> 
>  typedef void (*trap_exit_t)(const struct sbi_trap_regs *regs);
> --
> 2.20.1