From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756654AbcLPSAH (ORCPT ); Fri, 16 Dec 2016 13:00:07 -0500 Received: from mail-lf0-f65.google.com ([209.85.215.65]:34137 "EHLO mail-lf0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756382AbcLPR77 (ORCPT ); Fri, 16 Dec 2016 12:59:59 -0500 From: henrik@austad.us To: linux-kernel@vger.kernel.org Cc: Richard Cochran , henrik@austad.us, Henrik Austad , linux-media@vger.kernel.org, alsa-devel@vger.kernel.org, netdev@vger.kernel.org Subject: [TSN RFC v2 0/9] TSN driver for the kernel Date: Fri, 16 Dec 2016 18:59:04 +0100 Message-Id: <1481911153-549-1-git-send-email-henrik@austad.us> X-Mailer: git-send-email 2.7.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Henrik Austad The driver is directed via ConfigFS as we need userspace to handle stream-reservation (MSRP), discovery and enumeration (IEEE 1722.1) and whatever other management is needed. This also includes running an appropriate PTP daemon (TSN favors gPTP). Once we have all the required attributes, we can create link using mkdir, and use write() to set the attributes. Once ready, specify the 'shim' (basically a thin wrapper between TSN and another subsystem) and we start pushing out frames. The network part: it ties directly into the Rx-handler for receive and writes skb's using dev_queue_xmit(). This could probably be improved. 2 new fields in netdev_ops have been introduced, and the Intel igb-driver has been updated (as this an AVB-capable NIC which is available as a PCI-e card). What remains (tl;dr: a lot) a.k.a "Known problems" or "working on it!" - tie to (g)PTP properly, currently using ktime_get() for presentation time - get time from shim into TSN - let shim create/manage buffer - redo parts of the link-stuff using RCUs, the current setup is a bit clumsy. - The igb-driver does not work properly when compiled with IGB_TSN, some details in setting the register values needs to be figured out. I am working on this, but as it stands, the best bet is to load tsn using in_debug=1 to bypass the capability-check. I have had e1000 and sky2 running for several days without crashing, igb crashes and burns violently. - The ALSA driver does not handle multiple devices very well and is a work in progress. * v2: changes since v1 Changes since v1 - updated to latest upstream kernel (v4.8) - set dedicated enabled-attribute and let shim be stored in own (support future plan for enabling per-shim attributes) - fixed endianess issue in bitfields used in tsn-structs - Updated some of the trace-events to use trace_class - Fix various silly typos - Handle disabling of link from hrtimer a bit more gracefully (that actually works-ish). - use old skb and size of skb when that is set (Reporte by Nikita) - Move PCP-codes to NIC and not in the link itself - Allow TSN-capable card to be loaded even when in debug-mode (and do not enforce TSN behaviour) - Start hooking into ALSA's get_time_info hooks (very much incomplete) - use threads for sending frames, wake from hrtimer-callback. This also queues up awaiting timers if we fail to complete the transmit before another timer arrives, it will immediately execute another iteration, so no events should be lost. That being said, should this happen, it is a clear bug as we really should complete well before the next interval. - Cleanup link-locking and differentiate between Talker and Listener (as Listener grab link-lock from IRQ context) - Change list-lock to spinlock as we may need to take a link-lock whilst holding the master list-lock. - Do a more careful dance holding the spinlocks to regions only doing actual update. Network driver (I210 only) - bring up all Tx-/Rx-queues when igb is in TSN-mode regardless of how many CPUs the system has for I210 - Correctly calculate the idle_slope in I210's configure hook - Update igb-driver with queue-select and return correct queue when sending TSN-frames - add IGB_FLAG_QAV_PRIO flag to igb_adapter (to handle proper config of tx-ring when adapter is brought up. - add TXDCTL logic (part of preparatory work for TSN) to igb-driver - Improve SR(A|B) accountingo ALSA Shim - Allow userspace to grab much smaller chunks of data (down to a single Class A frame for S16_LE 2ch 48kHz). - Create the card with index/id pattern to avoid collision with other cards. * v1 Before reading on - this is not even beta, but I'd really appreciate if people would comment on the overall architecture and perhaps provide some pointers to where I should improve/fix/update - thanks! This is a very early RFC for a TSN-driver in the kernel. It has been floating around in my repo for a while and I would appreciate some feedback on the overall design to avoid doing some major blunders. There are at least one AVB-driver (the AV-part of TSN) in the kernel already. This driver aims to solve a wider scope as TSN can do much more than just audio. A very basic ALSA-driver is added to the end that allows you to play music between 2 machines using aplay in one end and arecord | aplay on the other (some fiddling required) We have plans for doing the same for v4l2 eventually (but there are other fishes to fry first). The same goes for a TSN_SOCK type approach as well. Henrik Austad (9): igb: add missing fields to TXDCTL-register TSN: add documentation TSN: Add the standard formerly known as AVB to the kernel Adding TSN-driver to Intel I210 controller Add TSN header for the driver Add TSN machinery to drive the traffic from a shim over the network Add TSN event-tracing AVB ALSA - Add ALSA shim for TSN MAINTAINERS: add TSN/AVB-entries Documentation/TSN/tsn.txt | 345 ++++++++ MAINTAINERS | 14 + drivers/media/Kconfig | 15 + drivers/media/Makefile | 2 +- drivers/media/avb/Makefile | 5 + drivers/media/avb/avb_alsa.c | 793 +++++++++++++++++ drivers/media/avb/tsn_iec61883.h | 152 ++++ drivers/net/ethernet/intel/Kconfig | 18 + drivers/net/ethernet/intel/igb/Makefile | 2 +- drivers/net/ethernet/intel/igb/e1000_82575.h | 4 + drivers/net/ethernet/intel/igb/igb.h | 26 + drivers/net/ethernet/intel/igb/igb_main.c | 39 +- drivers/net/ethernet/intel/igb/igb_tsn.c | 468 ++++++++++ include/linux/netdevice.h | 44 + include/linux/tsn.h | 952 +++++++++++++++++++++ include/trace/events/tsn.h | 333 ++++++++ net/Kconfig | 1 + net/Makefile | 1 + net/tsn/Kconfig | 32 + net/tsn/Makefile | 6 + net/tsn/tsn_configfs.c | 673 +++++++++++++++ net/tsn/tsn_core.c | 1189 ++++++++++++++++++++++++++ net/tsn/tsn_header.c | 162 ++++ net/tsn/tsn_internal.h | 397 +++++++++ net/tsn/tsn_net.c | 392 +++++++++ 25 files changed, 6061 insertions(+), 4 deletions(-) create mode 100644 Documentation/TSN/tsn.txt create mode 100644 drivers/media/avb/Makefile create mode 100644 drivers/media/avb/avb_alsa.c create mode 100644 drivers/media/avb/tsn_iec61883.h create mode 100644 drivers/net/ethernet/intel/igb/igb_tsn.c create mode 100644 include/linux/tsn.h create mode 100644 include/trace/events/tsn.h create mode 100644 net/tsn/Kconfig create mode 100644 net/tsn/Makefile create mode 100644 net/tsn/tsn_configfs.c create mode 100644 net/tsn/tsn_core.c create mode 100644 net/tsn/tsn_header.c create mode 100644 net/tsn/tsn_internal.h create mode 100644 net/tsn/tsn_net.c -- 2.7.4