[PATCH] drm/amd/pm: Send message when resp status is 0xFC

[Lazar, Lijo]

[AMD Official Use Only]

> That is the caller can perform something like issuing the same message again without prerequisites check on PMFW busy 

This patch expects this method. Caller may try to resend message again. As part of message sending, driver first checks response register. Current logic blocks sending any message if it sees 0xFC in response register, this patch is to address that. 

Thanks,
Lijo

-----Original Message-----
From: Quan, Evan <Evan.Quan at amd.com> 
Sent: Friday, February 25, 2022 11:07 AM
To: Lazar, Lijo <Lijo.Lazar at amd.com>; amd-gfx at lists.freedesktop.org
Cc: Zhang, Hawking <Hawking.Zhang at amd.com>; Deucher, Alexander <Alexander.Deucher at amd.com>; Wang, Yang(Kevin) <KevinYang.Wang at amd.com>
Subject: RE: [PATCH] drm/amd/pm: Send message when resp status is 0xFC

[AMD Official Use Only]

This may introduce some problems for two callers scenarios. That is the 2nd one will still proceed even if the 1st one was already blocked.
Maybe the logics here should be performed by the caller. That is the caller can perform something like issuing the same message again without prerequisites check on PMFW busy.
Or we can just update the smu_cmn_send_smc_msg APIs to give it another try on PMFW busy.

BR
Evan
> -----Original Message-----
> From: Lazar, Lijo <Lijo.Lazar at amd.com>
> Sent: Friday, February 25, 2022 12:22 PM
> To: amd-gfx at lists.freedesktop.org
> Cc: Zhang, Hawking <Hawking.Zhang at amd.com>; Deucher, Alexander 
> <Alexander.Deucher at amd.com>; Wang, Yang(Kevin) 
> <KevinYang.Wang at amd.com>; Quan, Evan <Evan.Quan at amd.com>
> Subject: [PATCH] drm/amd/pm: Send message when resp status is 0xFC
> 
> When PMFW is really busy, it will respond with 0xFC. However, it 
> doesn't change the response register state when it becomes free. 
> Driver should retry and proceed to send message if the response status is 0xFC.
> 
> Signed-off-by: Lijo Lazar <lijo.lazar at amd.com>
> ---
>  drivers/gpu/drm/amd/pm/swsmu/smu_cmn.c | 2 --
>  1 file changed, 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/pm/swsmu/smu_cmn.c
> b/drivers/gpu/drm/amd/pm/swsmu/smu_cmn.c
> index 590a6ed12d54..92161b9d8c1a 100644
> --- a/drivers/gpu/drm/amd/pm/swsmu/smu_cmn.c
> +++ b/drivers/gpu/drm/amd/pm/swsmu/smu_cmn.c
> @@ -297,7 +297,6 @@ int smu_cmn_send_msg_without_waiting(struct
> smu_context *smu,
>  	reg = __smu_cmn_poll_stat(smu);
>  	res = __smu_cmn_reg2errno(smu, reg);
>  	if (reg == SMU_RESP_NONE ||
> -	    reg == SMU_RESP_BUSY_OTHER ||
>  	    res == -EREMOTEIO)
>  		goto Out;
>  	__smu_cmn_send_msg(smu, msg_index, param); @@ -391,7 +390,6 @@ int 
> smu_cmn_send_smc_msg_with_param(struct
> smu_context *smu,
>  	reg = __smu_cmn_poll_stat(smu);
>  	res = __smu_cmn_reg2errno(smu, reg);
>  	if (reg == SMU_RESP_NONE ||
> -	    reg == SMU_RESP_BUSY_OTHER ||
>  	    res == -EREMOTEIO) {
>  		__smu_cmn_reg_print_error(smu, reg, index, param, msg);
>  		goto Out;
> --
> 2.25.1