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 7CB752DF68 for ; Wed, 14 May 2025 00:31:40 +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=1747182700; cv=none; b=aYV3BSVeMONsaZTHGdDYT8ElCyj7hKBTR2oFj36UlsYnQB8bYhBPKCrXEB9fPp3A7wOCU4j706oNMmsBTXiEkxcjMEVM69Ieu5E+mFo50NFVBL0Mp/cgITrAcqvIjihmr8EKO5eUAozVg5ulmSr1JjSq+RCQHxWz7/VFbtXHV7E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747182700; c=relaxed/simple; bh=JsECoFxdH2WSSQjwVZ3sfrsREVyyl6kTU30w/228gj0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=GpxZlWdPOMzr8xN/7RysJb9FQxGoe4tlf5JszasRUXYuW1ogw0meodBiG09kVRKgqNCFpAfnfyhhdLao+iec0OdgHlKdJHLoBymJs1aMcTKqiLeanpqQmh48vCKGZ0sHJXvwMAUQ/zKns1QAgExQUbJU23nyWYqOnUfyw29QgMY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id D6DC9C4CEE4; Wed, 14 May 2025 00:31:39 +0000 (UTC) From: Dave Jiang To: linux-cxl@vger.kernel.org Cc: dave@stgolabs.net, jonathan.cameron@huawei.com, alison.schofield@intel.com, vishal.l.verma@intel.com, ira.weiny@intel.com, dan.j.williams@intel.com, gourry@gourry.net Subject: [PATCH 3/4] cxl: docs/platform/acpi/srat Add generic target documentation Date: Tue, 13 May 2025 17:31:32 -0700 Message-ID: <20250514003133.584401-4-dave.jiang@intel.com> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250514003133.584401-1-dave.jiang@intel.com> References: <20250514003133.584401-1-dave.jiang@intel.com> Precedence: bulk X-Mailing-List: linux-cxl@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Add description in the SRAT document to descript the Generic Port Affinity sub-table. Signed-off-by: Dave Jiang --- .../driver-api/cxl/platform/acpi/srat.rst | 21 +++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/Documentation/driver-api/cxl/platform/acpi/srat.rst b/Documentation/driver-api/cxl/platform/acpi/srat.rst index cc7687645de7..500413b96e70 100644 --- a/Documentation/driver-api/cxl/platform/acpi/srat.rst +++ b/Documentation/driver-api/cxl/platform/acpi/srat.rst @@ -42,3 +42,24 @@ Example :: Enabled : 1 Hot Pluggable : 1 Non-Volatile : 0 + + +Generic Port Affinity +===================== +The Generic Port Affinity subtable provides an association between a proximity +domain and a device handle representing a Generic Port such as a CXL host +bridge. With the association, latency and bandwidth numbers can be retrieved +from the SRAT for the path between CPU(s) (initiator) and the Generic Port. +This helps with constructing the performance coordinates for CXL devices that +are hot-plugged and not able to be enumerated by the platform firmware. + +Example :: + + Subtable Type : 06 [Generic Port Affinity] + Length : 20 <- 32d, length of table + Reserved : 00 + Device Handle Type : 00 <- 0 - ACPI, 1 - PCI + Proximity Domain : 00000001 + Device Handle : ACPI0016:01 + Flags : 00000001 <- Bit 0 (Enabled) + Reserved : 00000000 -- 2.49.0