From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 86534364950; Wed, 27 May 2026 14:46:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779893204; cv=none; b=EsUKjXVdxjdoo79SKcEQCIlAhaOt241/fg0BhPeqA8Kp+pJsbp/HP5oL7C1gJR8KhGKzHqc3zsMU/2bKzNRCBC8Vs0rKlJEvpVXuqGhaOFXwRUbMrhqg8+reVf+QnqlCVdjRpnbV/6uRLpPZZ+8cxyt+A8u3r+jk3DcVkGLGp4Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779893204; c=relaxed/simple; bh=H/Rms+6k759DaPc6FDpjuNlaRYkZn3kPIXxHOVWODS4=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=BP//3RKMYr3nSx8MwZKeAeRcAyaQ+1M9R8s6pxt7Uu7xhAR80DyUfQ7BS0ecq+09ZQbB/1iRbffihcntKn2yxOcB9x+nyYY6LQFJlyzCfZgoznK2I/GtAFjxzc/gPMMu3kHnDiVEZ1AMuD/1iZ1q4yM5iMOekONVk9/N+uhYgnI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=jTf2cAd7; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="jTf2cAd7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CA1871F000E9; Wed, 27 May 2026 14:46:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1779893203; bh=6y6ydWz8U6vpPf9Y84EwbWZmzk5t5YC6HCWXZ30d3Eo=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=jTf2cAd77cfiJqeIaPBBOR5/mlrwDMnNZQziAYpOq2tvw1HF5b/nnK7xI9TJsGjhy qXkAvRDYDkRZxHog+SiL3oS4ohyqpYhWfo7lbHe8brRPZ0+zQHVbG+qnNqfiRhuk03 RYF+BPntsjZKvtLJ/4qL6zf9AtWY0pSNWKVGeW+rmdcwmJ5+WSU1kTRIz8IjMuTWUC epeZACShlFe5ojSY35vwacKnlevca6thmIlFfwoLplmMhm2xvS2pOR/6f1bGc+qN5E rBOMTq5Y0H2ofBMuUnPE+qpOQ+nvNwE042UCvG9k6BFmv1jGVoSJNXgAFc5taCEQJa F1I6XVO1KuRJA== Message-ID: <2ba14e8a-1664-48fe-ba99-c81100de78f4@kernel.org> Date: Wed, 27 May 2026 16:46:38 +0200 Precedence: bulk X-Mailing-List: linux-tegra@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] memory: tegra: add multi-socket support to the memory interconnect To: Sumit Gupta , treding@nvidia.com, jonathanh@nvidia.com, linux-kernel@vger.kernel.org, linux-tegra@vger.kernel.org Cc: bbasu@nvidia.com References: <20260521140546.3023819-1-sumitg@nvidia.com> <2caba07a-511e-453c-8e1e-f2b07b84a096@kernel.org> <58ae92f3-3e6d-4f60-970e-76ee4d7dbd4e@nvidia.com> From: Krzysztof Kozlowski Content-Language: en-US Autocrypt: addr=krzk@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 8bit On 27/05/2026 16:21, Sumit Gupta wrote: > > On 27/05/26 18:25, Krzysztof Kozlowski wrote: >> External email: Use caution opening links or attachments >> >> >> On 21/05/2026 16:05, Sumit Gupta wrote: >>> - err = icc_link_create(node, TEGRA_ICC_MC); >>> + err = tegra_mc_icc_link_create(node, node_id, TEGRA_ICC_MC); >>> if (err) >>> goto remove_nodes; >>> >>> @@ -957,7 +969,13 @@ static int tegra_mc_probe(struct platform_device *pdev) >>> if (IS_ERR(mc->regs)) >>> return PTR_ERR(mc->regs); >>> >>> - mc->debugfs.root = debugfs_create_dir("mc", NULL); >>> + if (!mc_debugfs_root) >> That's a probe path and you created a singletone. Looks like preventing >> async probing for no real reason. >> >> I am very against singletons and debugfs does not look like justified >> exception. > > The singleton was added so multi-socket MC/EMC instances could > share a "mc"/"emc" parent. I'll drop it in v2. > > On single-socket SoCs, the "mc"/"emc" names will be unchanged. > On multi-socket SoCs, each instance will create a top-level debugfs > dir named with dev_name(). Same pattern in tegra186-emc.c. > >   if (dev_to_node(mc->dev) == NUMA_NO_NODE) >       mc->debugfs.root = debugfs_create_dir("mc", NULL); >   else >       mc->debugfs.root = debugfs_create_dir(dev_name(mc->dev), NULL); You assume this is fully synced, so you as well could do a look up and then use what you found or create new dir. If you think that is racy, so is this approach... How are other drivers handling per-device debugfs directories? Do they also create such in the top-level? I think no. Best regards, Krzysztof