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 CB7B01DE4D5; Fri, 21 Feb 2025 15:53:58 +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=1740153238; cv=none; b=oM7PhGQfL/4ax9i+1fNueHCWeoU4svv4dqdsrdwVwDaHnIcJ8o7wKgOLdCO70dlxYZ2sunie+w9PZQuAaLHdrXgYMtwoB8Wyzy5LI/b9+BBMANwmsx+bjPLp4uzlx9Lxf5WpWQxwhvukiWLBz4Fz0ogk6bKtadYh6sydOQaJDzU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740153238; c=relaxed/simple; bh=PE0mUF1LBVVFVnCNM9w16uhviJ1kUZEN7P9yj/uxKuE=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=gtmU9SHBDeNcRE7epEiNoFiPe8KhGBmHJBouMsCBhHkg+S7hs3M35DamhSgcel2fUKq5JVXN9xyh3tYE+fwSAh1vodAiEVVBBhMrI6xPIVztYuOfqfHJN6BrmqcdaqwlYN2qZ5m1QdTFVyEXH3b0+bsEvWzBUUodvp8RkJOkoeE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=frCVHTpj; 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="frCVHTpj" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 106DDC4CED6; Fri, 21 Feb 2025 15:53:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1740153238; bh=PE0mUF1LBVVFVnCNM9w16uhviJ1kUZEN7P9yj/uxKuE=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=frCVHTpj23uJeJovj8cgXfHA5bIObJ2tSBfABOIJDKzPYNWgf/3OACabEqrHAAH17 sRyUVQbUZgA6wDff9xtSf7/HDK8v9tQGt01BDl+IDy6qZqk3qIrrHA7Y5u8Ylp215V Kw1CZFR+Hl83AIdU7zzphxAXoePJd7NYP58BsgoFzvRcSwhf7qUpiaDZO8pF+BDU4R fDUlI+ETMleS5y5r1Lm7R5b+9o2lgW0Xf1utO2aODFIyQLz4qmVBFy0X3leqwS4nrA ST715VXNReZhQieHhLqchSCY3jKwpdiGl93MNDtPfP7aID2vY3VFMcAbK1dHOTi555 iqg152qm8Tvjg== X-Mailer: emacs 29.4 (via feedmail 11-beta-1 I) From: Aneesh Kumar K.V To: Dan Williams , Dan Williams , linux-coco@lists.linux.dev Cc: Bjorn Helgaas , Lukas Wunner , Samuel Ortiz , Alexey Kardashevskiy , Xu Yilun , linux-pci@vger.kernel.org, gregkh@linuxfoundation.org Subject: Re: [PATCH 08/11] PCI/IDE: Add IDE establishment helpers In-Reply-To: <67b6a3fa7ffb4_2d2c2947f@dwillia2-xfh.jf.intel.com.notmuch> References: <173343739517.1074769.13134786548545925484.stgit@dwillia2-xfh.jf.intel.com> <173343744264.1074769.10935494914881159519.stgit@dwillia2-xfh.jf.intel.com> <67b6a3fa7ffb4_2d2c2947f@dwillia2-xfh.jf.intel.com.notmuch> Date: Fri, 21 Feb 2025 21:23:50 +0530 Message-ID: Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Dan Williams writes: > Aneesh Kumar K.V wrote: > [..] >> >> Also wondering should the stream id be unique at the rootport level? ie >> for a config like below >> >> # pwd >> /sys/devices/platform/40000000.pci/pci0000:00 >> # ls >> 0000:00:01.0 available_secure_streams power >> 0000:00:02.0 pci_bus uevent >> # lspci >> 00:01.0 PCI bridge: ARM Device 0def >> 00:02.0 PCI bridge: ARM Device 0def >> 01:00.0 Unassigned class [ff00]: ARM Device ff80 >> 02:00.0 SATA controller: Device 0abc:aced (rev 01) >> # >> # lspci -t >> -[0000:00]-+-01.0-[01]----00.0 >> \-02.0-[02]----00.0 >> # >> >> >> I should be able to use the same stream id to program both the rootports? > > For all the IDE capable platforms I know of the stream id allocation > pool is segmented per host-bridge. Do you have a use case where root > ports that share a host-bridge each have access to a distinct pool of > IDE stream ids? I am using FVP simulator for my development. Hence no real device. The spec= states: " All IDE TLPs must be associated with an IDE Stream, identified via an IDE S= tream ID. =E2=97=A6 Software must assign IDE Stream IDs such that two Partner Ports u= se the same value for a given IDE Stream. =E2=97=A6 Software must assign IDE Stream IDs such that every enabled IDE S= tream associated with a given terminal Port is assigned a unique Stream ID value at that Port =E2=97=A6 It is permitted for a platform to further restrict the assignment= of Stream IDs. " If I understand correctly, the stream ID allocation pool per host bridge qualifies as an additional platform restriction? If so, why is Linux enforcing it? Wouldn=E2=80=99t it be more appropriate for the platform code= to handle this instead? -aneesh