From patchwork Fri Nov 19 22:07:47 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jim Quinlan X-Patchwork-Id: 12629595 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1561DC433FE for ; Fri, 19 Nov 2021 22:08:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230011AbhKSWLE (ORCPT ); Fri, 19 Nov 2021 17:11:04 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50590 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229675AbhKSWLE (ORCPT ); Fri, 19 Nov 2021 17:11:04 -0500 Received: from mail-pl1-x62f.google.com (mail-pl1-x62f.google.com [IPv6:2607:f8b0:4864:20::62f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 18038C061574; Fri, 19 Nov 2021 14:08:02 -0800 (PST) Received: by mail-pl1-x62f.google.com with SMTP id n8so9162930plf.4; Fri, 19 Nov 2021 14:08:02 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id; bh=oVfWHfQ93NSK7GJnUuUHGV5hxlYSbDYnzx268qbi4wQ=; b=DrMbXeGjsBIOvXymVZJLXz0Ts4VKlFMQ5+D7t0BLGO+nSns99UoImMQ9dQM0V0/ta2 r/sq4+URBIiypx6oehS67YaPhLRyyffvsT0rpxqeSnr2KqoITs3pMhUioRLhKi5lWom3 81D2ZM2EUp2J++43GaGS0+b3uBalOb8gDQPPRgJXYTI4Ct2JPhhS75oc7Wiw26GVm9Wa jny0uMveQ8QfTp8Az1ufaowlqbh74o37KX0QjmhiHhH4tNIDbHcMV3CSOJJZRzdIC5ft lhHmgpwIt6RJbgRxCeUwO8B7qvjoS7AMGB4ihBK+9oXZ9/Gs+HPDtfXO7QvBoLLU0E2/ A4jA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=oVfWHfQ93NSK7GJnUuUHGV5hxlYSbDYnzx268qbi4wQ=; b=S4wUAUKwFEH2mciN7hlhefHr7nnEYRq7q3OWf6Qslujs78i3lSmRbX4r1iZnM96m4A NOUtnJ9lMgklbbXEP8CoF1V/znlBSfMeVGZX70L1oHNY66QRgYgAXyLbgq68ks26XquX Oj+JXwjHEWGehhDFybXDkBr/hMmsb0L+SoPMHJHrOZBo01foEooSUMSKQYJGoiKd2xPm rTBYQuOG0IDHKzfLIauGxySTF7ERC8TazzRHXKFquXd6Tilnln3HkEzej5qxe7cQoy3F mSwZjy3HSz78RZsJRLvVM6lom677IlOz0/xgYh+t2PMO2xH9c68Py6ibNhZ7o4DCk5R0 YTBg== X-Gm-Message-State: AOAM530fx/faRozCgr/Adugpj0rGJ7XFI8KlzMcBmGL7S/swTbipYefd txeM9d1ZX9LfzxQK1O6aPIrItc+yvtvJuw== X-Google-Smtp-Source: ABdhPJy6hljmQzcSBrpyEVHVbSYVTYLUiWYEJ667fFb1TruKTPKZac2o/MSnsjCJGs1XfIEGMWjF2w== X-Received: by 2002:a17:90a:c78f:: with SMTP id gn15mr3814496pjb.54.1637359681068; Fri, 19 Nov 2021 14:08:01 -0800 (PST) Received: from stbsrv-and-01.and.broadcom.net ([192.19.11.250]) by smtp.gmail.com with ESMTPSA id t2sm612940pfd.36.2021.11.19.14.07.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 19 Nov 2021 14:08:00 -0800 (PST) From: Jim Quinlan To: linux-pci@vger.kernel.org, Bjorn Helgaas , Nicolas Saenz Julienne , Rob Herring , Mark Brown , bcm-kernel-feedback-list@broadcom.com, jim2101024@gmail.com, james.quinlan@broadcom.com Cc: devicetree@vger.kernel.org (open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS), =?utf-8?q?Krzysztof_Wilczy=C5=84ski?= , linux-arm-kernel@lists.infradead.org (moderated list:BROADCOM BCM2711/BCM2835 ARM ARCHITECTURE), linux-kernel@vger.kernel.org (open list), linux-rpi-kernel@lists.infradead.org (moderated list:BROADCOM BCM2711/BCM2835 ARM ARCHITECTURE), Saenz Julienne Subject: [PATCH v9 0/7] PCI: brcmstb: root port turns on sub-device power Date: Fri, 19 Nov 2021 17:07:47 -0500 Message-Id: <20211119220756.18628-1-jim2101024@gmail.com> X-Mailer: git-send-email 2.17.1 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org v9 -- Simplify where this mechanism works: instead of looking for regulators below every bridge, just look for them at the bridge under the root bus (root port). Now there is no modification of portdrv_{pci,core}.c in this submission. -- Although Pali is working on support for probing native PCIe controller drivers, this work may take some time to implement and it still might not be able to accomodate our driver's requirements (e.g. vreg suspend/resume control). -- Move regulator suspend/resume control to Brcm RC driver. It must reside there because (a) in order to know when to initiate linkup during resume and (b) to turn on the regulators before any config-space accesses occur. -- Commit message spelling, word choice (Bjorn, Krzysztof) -- Refactor a small commit that was ignoring a funcs' return values (Bjorn). -- Here is a summary of this mechanism: If: -- PCIe RC driver sets pci_ops {add,remove)_bus to pci_subdev_regulators_{add,remove}_bus during its probe. -- There is a DT node "RB" under the host bridge DT node. -- During the RC driver's pci_host_probe() the add_bus callback is invoked where (bus->parent && pci_is_root_bus(bus->parent) is true Then: -- A struct subdev_regulators structure will be allocated and assigned to bus->dev.driver_data. -- regulator_bulk_{get,enable}() will be invoked on &bus->dev and the former will search for and process any vpcie{12v,3v3,3v3aux}-supply properties that reside in node "RB". -- The regulators will be turned off/on for any unbind/bind operations. -- The regulators will be turned off/on for any suspend/resumes, but only if the RC driver handles this on its own. This will appear in a later commit for the pcie-brcmstb.c driver. v8 -- Only the two binding commits and the "Change brcm_phy_stop()" commit are unchanged. -- The code has been moved to portdrv_pci.c and bus.c. The regulators are placed in bus->dev.driver_data (bus->sysdata is already occupied by the Broadcom PCIe). Two functions, pci_subdev_regulators_{add,remove}_bus() are created to turn the regulators on/off. The pcie_portdriver also sets its pci_driver methods suspend and resume when the conditions are right for this feature. (Robh for suggestions, although I probably erred in following them). -- Have the root complex return 0xffffffff on accesses even when the link is down and the HW doesn't support such accesses (PaliR). -- Just call devm_bulk_regulator_get() on standard supplies; don't bother pre-scanning the DT for them (MarkB). v7 -- RobH suggested putting the "vpcixxx-supply" property under the bridge-node rather than the endpoint device node. Also, he said to use the pci-ops add_bus/remove methods. Doing so simplifies the code greatly and three commits were dropped. Thanks! -- Rob also suggested (I think) having this patchset be a general feature which is activated by an OF property under the bridge node. I tried to do that but realized that our root complex driver controls the regulators with its dev_pm_ops and there is no way to transfer this control when using general mechanism. Note that although the regulator core deals with suspend, our RC driver wants the right to sometimes to preclude this for WOL scenarios. -- One commit was added to change the response to the return value of the pci_ops add_bus() method. Currently, an error causes a WARNING, a dev_err(...), and continues to return the child bus. The modification was, for returning -ENOLINK only, to skip WARNING & dev_err() and return NULL. This is necessary for our RC HW, as if the code continues on it will do a pci_read_config_dword() for the vendor/id, and our HW flags a CPU abort (instead of returning 0xffffffff) when the is no pcie-link established. [NOTE: MarkB, I did not add one of your two "Reviewed-by"s because the commit had a decent amount of change.] v6 -- Dropped the idea of a placeholder regulator property (brcm-ep-a-supply). (MarkB) -- device_initialize() now called once. Two commits were added for this. (GKH) -- In two cases, separated a single function into two or more functions (MarkB) -- "(void)foo();" => "foo()". Note that although foo() returns an int, in this instance it is being invoked within a function returning void, and foo() already executes a dev_err() on error. (MarkB) -- Added a commit to correct PCIe interrupts in YAML. -- Removed "device_type = "pci";" for the EP node in the YAML example. -- Updated the URL related to the voltage regulator names on GitHub. Note that I added vpciev3v3aux. v5 [NOTE: It has been a while since v4. Sorry] -- See "PCI: allow for callback to prepare nascent subdev" commit message for the cornerstone of this patchset and the reasons behind it. This is a new commit. -- The RC driver now looks into its DT children and turns on regulators for a sub-device, and this occurs prior to PCIe link as it must. -- Dropped commits not related to the focus of this patchset. v4 [NOTE: I'm not sure this fixes RobH and MarkB constraints but I'd like to use this pullreq as a basis for future discussion.] [Commit: Add bindings for ...] -- Fix syntax error in YAML bindings example (RobH) -- {vpcie12v,vpcie3v3}-supply props are back in root complex DT node (I believe RobH said this was okay) [Commit: Add control of ..] -- Do not do global search for regulator; now we look specifically for the property {vpcie12v,vpcie3v3}-supply in the root complex DT node and then call devm_regulator_bulk_get() (MarkB) -- Use devm_regulator_bulk_get() (Bjorn) -- s/EP/slot0 device/ (Bjorn) -- Spelling, capitalization (Bjorn) -- Have brcm_phy_stop() return a void (Bjorn) [Commit: Do not turn off ...] -- Capitalization (Bjorn) [Commit: Check return value ...] -- Commit message content (Bjorn) -- Move 6/6 hunk to 2/6 where it belongs (Bjorn) -- Move the rest of 6/6 before all other commits (Bjorn) v3 -- Driver now searches for EP DT subnode for any regulators to turn on. If present, these regulators have the property names "vpcie12v-supply" and "vpcie3v3-supply". The existence of these regulators in the EP subnode are currently pending as a pullreq in pci-bus.yaml at https://github.com/devicetree-org/dt-schema/pull/54 (MarkB, RobH). -- Check return of brcm_set_regulators() (Florian) -- Specify one regulator string per line for easier update (Florian) -- Author/Committer/Signoff email changed from that of V2 from 'james.quinlan@broadcom.com' to 'jim2101024@gmail.com'. v2 -- Use regulator bulk API rather than multiple calls (MarkB). v1 -- Bindings are added for fixed regulators that may power the EP device. -- The brcmstb RC driver is modified to control these regulators during probe, suspend, and resume. -- 7216 type SOCs have additional error reporting HW and a panic handler is added to dump its info. -- A missing return value check is added. Jim Quinlan (7): PCI: brcmstb: Fix function return value handling dt-bindings: PCI: Correct brcmstb interrupts, interrupt-map. dt-bindings: PCI: Add bindings for Brcmstb EP voltage regulators PCI: Add mechanism to turn on subdev regulators PCI: brcmstb: Split brcm_pcie_setup() into two funcs PCI: brcmstb: Add control of subdevice voltage regulators PCI: brcmstb: Do not turn off WOL regulators on suspend .../bindings/pci/brcm,stb-pcie.yaml | 31 ++- drivers/pci/bus.c | 67 ++++++ drivers/pci/controller/pcie-brcmstb.c | 209 +++++++++++++++--- drivers/pci/pci.h | 8 + 4 files changed, 277 insertions(+), 38 deletions(-) base-commit: ee1703cda8dc777e937dec172da55beaf1a74919 prerequisite-patch-id: 0905430e81a95900a1366916fe2940b848317a7c prerequisite-patch-id: 710896210c50354d87f6025fe0bd1b89981138eb prerequisite-patch-id: 97d3886cb911cb12ef3d514fdfff2a0ab11e8570 prerequisite-patch-id: 241f1e1878fc177d941f4982ca12779a29feb62b prerequisite-patch-id: d856608825e2294297db5d7f88f8c180f3e5a1f2 prerequisite-patch-id: 92bcbc9772fb4d248157bcf35e799ac37be8ee45 prerequisite-patch-id: 6f4b1aac459bb54523ade0e87c04e9d6c45bd9f5 prerequisite-patch-id: 090ee7a3112a4ecb03805b23ed10e2c96b3b34ed