From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 93BA82F2A for ; Wed, 20 Nov 2024 21:07:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732136868; cv=none; b=b26bVp2V4cE0TDZ4JKHiaUKjlKK57yB5Fd0DFBoFiN5bm5jlWLFycWVS26aEdF33TjKV3lmaDCTj88yMYBjZ3UwyFXRbNwV+NteUX58AuZOTVsJtNhRLHM6UJJjuDNLV1jA9ymO+8cJfoPkGnxVJlqSNTJ18k9sp7ny63DprHUg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732136868; c=relaxed/simple; bh=LBbdjy+TYOCJ9t+XX3uYFw4y+bCWX0vGoAICMMzs6eM=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type: Content-Disposition:In-Reply-To; b=q/70sl9tpCg0524KZXZfuu+m4HRphVixWZ3mcB5MBjJiTxOhnzZ8AUJJooNcgRX2oCoTgSZn1S4u+813TW+V8AZ8kGywLJi9k8x1b2Xk6PSmu0PZSkBaZYqWpCwx9dtXqPrTOwaXPHpY/xI1JwF6+6dloAIDVqZrQ4AJcnBaaPs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Vh5Rswhl; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Vh5Rswhl" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E1060C4CECD; Wed, 20 Nov 2024 21:07:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1732136868; bh=LBbdjy+TYOCJ9t+XX3uYFw4y+bCWX0vGoAICMMzs6eM=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=Vh5RswhlQ5CAz7lPYydTwIlBmeRw3kKZhMKM6LAch2wAKGdYHCxieSDYgx5GRxd5q l9ekxI1+hrUpDTaZHJW4I//7GfQPcB0WydjN7KXErDtpwekXZiBED61IKceycB4plj VVwntJpSHDga02HOqweVH9eLPlY1ggX+w1D1gYJG91jcUqPIVmvUY3aT6KCyP+Ivf9 9YfKLulmQz5jUjcpFmhjlZ+e3yfjSpNUO9X5oXmx4uPzt06fuE+3eFs/7fro4Rqbqt h7ykS1bavTZX7eoULH2Wqmh1h7bZEnSuy3KXMXL5tzu1d6MjEdihXbJwE+0uC/zB4C JZSHIprFWEK7w== Date: Wed, 20 Nov 2024 15:07:46 -0600 From: Bjorn Helgaas To: Mariusz Tkaczyk Cc: Szymon Durawa , Bjorn Helgaas , Dan Williams , Lukas Wunner , linux-pci@vger.kernel.org, Nirmal Patel Subject: Re: [PATCH v2 0/8] VMD add second rootbus support Message-ID: <20241120210746.GA2353848@bhelgaas> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20241120101021.00007003@linux.intel.com> On Wed, Nov 20, 2024 at 10:10:21AM +0100, Mariusz Tkaczyk wrote: > On Fri, 15 Nov 2024 11:48:55 -0600 > Bjorn Helgaas wrote: > > > The "BUS0" nomenclature seems heavily embedded in the vmd driver but > > is really a misnomer. Maybe that reflects similar terminology in an > > internal spec? Any hard-wiring of bus numbers reflects a property of > > the way a *Root Port* works, so using the right name will make this > > easier to understand, especially since there are other Root Ports with > > the same hard wiring. > > It is named as BUS_0 and BUS_1 because it refers to kernel's > pci_create_root_bus()`, we simplified it for better code wrapping. > > Looks like it confuses you, do you like ROOT_BUS0 and ROOT_BUS1 better? > > I don't see better fit than "root bus" because we are creating new root buses > accordingly. I was trying to use standard PCIe spec terminology where possible, but I misspoke above, sorry. I think we should pretend I never wrote that paragraph, and also ignore my suggestion about replacing "rootbus" with "Root Port" in the 7/8 commit log (sorry to everybody who never got the patches I was responding to). A "root bus" is the *primary* bus of a Root Port, so the root bus number is determined by the host bridge, which I guess would be considered part of a PCIe Root Complex. > Internally, it is called as "VMD domain" and each VMD Domain is presented as > separate pci root bus. > > The original naming is presented in the sysfs links: > - "domain" -> root bus 0 > = "domain1" -> root bus 1 > > i.e: > domain -> pci10000:e0/pci_bus/10000:e0 > domain1 -> pci10000:e1/pci_bus/10000:e1 That's fine, I'm not suggesting any sysfs change to this. Bjorn