Received-SPF: pass (google.com: domain of linux-kernel+bounces-204139-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.199.223 as permitted sender) client-ip=147.75.199.223;
Message-ID: <99d19104-875c-4214-b4a4-4c228cc08b66@collabora.com>
Date: Thu, 6 Jun 2024 12:50:56 +0200
Precedence: bulk
MIME-Version: 1.0
User-Agent: Mozilla Thunderbird
Subject: Re: [PATCH] remoteproc: mediatek: Don't print error when optional scp
 handle is missing
To: =?UTF-8?B?TsOtY29sYXMgRi4gUi4gQS4gUHJhZG8=?= <nfraprado@collabora.com>,
 Bjorn Andersson <andersson@kernel.org>,
 Mathieu Poirier <mathieu.poirier@linaro.org>,
 Matthias Brugger <matthias.bgg@gmail.com>
Cc: kernel@collabora.com, linux-remoteproc@vger.kernel.org,
 linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
 linux-mediatek@lists.infradead.org
References: <20240605-mt8195-dma-scp-node-err-v1-1-f2cb42f24d6e@collabora.com>
From: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Content-Language: en-US
In-Reply-To: <20240605-mt8195-dma-scp-node-err-v1-1-f2cb42f24d6e@collabora.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 8bit

Il 05/06/24 21:35, Nícolas F. R. A. Prado ha scritto:
> The scp_get() helper has two users: the mtk-vcodec and the mtk-mdp3
> drivers. mdp3 considers the mediatek,scp phandle optional, and when it's
> missing mdp3 will directly look for the scp node based on compatible.
> 
> For that reason printing an error in the helper when the handle is
> missing is wrong, as it's not always an actual error. Besides, the other
> user, vcodec, already prints an error message on its own when the helper
> fails so this message doesn't add that much information.
> 
> Remove the error message from the helper. This gets rid of the deceptive
> error on MT8195-Tomato:
> 
>    mtk-mdp3 14001000.dma-controller: can't get SCP node

I'm way more for giving it a SCP handle instead of silencing this print... the
SCP handle way *is* the correct one and I prefer it, as that'd also be the only
way to support Dual-Core SCP in MDP3.

I really want to see hardcoded stuff disappear and I really really *really* want
to see more consistency across DT nodes in MediaTek platforms.

So, still a one-line change, but do it on the devicetree instead of here please.

Cheers,
Angelo

> 
> Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
> ---
>   drivers/remoteproc/mtk_scp.c | 4 +---
>   1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/drivers/remoteproc/mtk_scp.c b/drivers/remoteproc/mtk_scp.c
> index b885a9a041e4..f813117b6312 100644
> --- a/drivers/remoteproc/mtk_scp.c
> +++ b/drivers/remoteproc/mtk_scp.c
> @@ -37,10 +37,8 @@ struct mtk_scp *scp_get(struct platform_device *pdev)
>   	struct platform_device *scp_pdev;
>   
>   	scp_node = of_parse_phandle(dev->of_node, "mediatek,scp", 0);
> -	if (!scp_node) {
> -		dev_err(dev, "can't get SCP node\n");
> +	if (!scp_node)
>   		return NULL;
> -	}
>   
>   	scp_pdev = of_find_device_by_node(scp_node);
>   	of_node_put(scp_node);
> 
> ---
> base-commit: d97496ca23a2d4ee80b7302849404859d9058bcd
> change-id: 20240605-mt8195-dma-scp-node-err-6a8dea26d4f5
> 
> Best regards,