From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C0EF7C433E0 for ; Mon, 1 Jun 2020 10:15:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 948D2206A4 for ; Mon, 1 Jun 2020 10:15:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725946AbgFAKP7 (ORCPT ); Mon, 1 Jun 2020 06:15:59 -0400 Received: from foss.arm.com ([217.140.110.172]:36018 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725935AbgFAKP5 (ORCPT ); Mon, 1 Jun 2020 06:15:57 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 30B8B1FB; Mon, 1 Jun 2020 03:15:56 -0700 (PDT) Received: from [192.168.2.22] (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 136723F305; Mon, 1 Jun 2020 03:15:54 -0700 (PDT) Subject: Re: [PATCH v3 04/20] arm64: dts: arm: vexpress: Move fixed devices out of bus node From: =?UTF-8?Q?Andr=c3=a9_Przywara?= To: Guenter Roeck , Rob Herring , Sudeep Holla Cc: Liviu Dudau , Lorenzo Pieralisi , Mark Rutland , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org References: <20200513103016.130417-1-andre.przywara@arm.com> <20200513103016.130417-5-andre.przywara@arm.com> <20200528024810.GA232303@roeck-us.net> <48afb8bb-a22a-54df-7751-55b7b84c3c88@arm.com> Autocrypt: addr=andre.przywara@arm.com; prefer-encrypt=mutual; keydata= xsFNBFNPCKMBEAC+6GVcuP9ri8r+gg2fHZDedOmFRZPtcrMMF2Cx6KrTUT0YEISsqPoJTKld tPfEG0KnRL9CWvftyHseWTnU2Gi7hKNwhRkC0oBL5Er2hhNpoi8x4VcsxQ6bHG5/dA7ctvL6 kYvKAZw4X2Y3GTbAZIOLf+leNPiF9175S8pvqMPi0qu67RWZD5H/uT/TfLpvmmOlRzNiXMBm kGvewkBpL3R2clHquv7pB6KLoY3uvjFhZfEedqSqTwBVu/JVZZO7tvYCJPfyY5JG9+BjPmr+ REe2gS6w/4DJ4D8oMWKoY3r6ZpHx3YS2hWZFUYiCYovPxfj5+bOr78sg3JleEd0OB0yYtzTT esiNlQpCo0oOevwHR+jUiaZevM4xCyt23L2G+euzdRsUZcK/M6qYf41Dy6Afqa+PxgMEiDto ITEH3Dv+zfzwdeqCuNU0VOGrQZs/vrKOUmU/QDlYL7G8OIg5Ekheq4N+Ay+3EYCROXkstQnf YYxRn5F1oeVeqoh1LgGH7YN9H9LeIajwBD8OgiZDVsmb67DdF6EQtklH0ycBcVodG1zTCfqM AavYMfhldNMBg4vaLh0cJ/3ZXZNIyDlV372GmxSJJiidxDm7E1PkgdfCnHk+pD8YeITmSNyb 7qeU08Hqqh4ui8SSeUp7+yie9zBhJB5vVBJoO5D0MikZAODIDwARAQABzS1BbmRyZSBQcnp5 d2FyYSAoQVJNKSA8YW5kcmUucHJ6eXdhcmFAYXJtLmNvbT7CwXsEEwECACUCGwMGCwkIBwMC BhUIAgkKCwQWAgMBAh4BAheABQJTWSV8AhkBAAoJEAL1yD+ydue63REP/1tPqTo/f6StS00g NTUpjgVqxgsPWYWwSLkgkaUZn2z9Edv86BLpqTY8OBQZ19EUwfNehcnvR+Olw+7wxNnatyxo D2FG0paTia1SjxaJ8Nx3e85jy6l7N2AQrTCFCtFN9lp8Pc0LVBpSbjmP+Peh5Mi7gtCBNkpz KShEaJE25a/+rnIrIXzJHrsbC2GwcssAF3bd03iU41J1gMTalB6HCtQUwgqSsbG8MsR/IwHW XruOnVp0GQRJwlw07e9T3PKTLj3LWsAPe0LHm5W1Q+euoCLsZfYwr7phQ19HAxSCu8hzp43u zSw0+sEQsO+9wz2nGDgQCGepCcJR1lygVn2zwRTQKbq7Hjs+IWZ0gN2nDajScuR1RsxTE4WR lj0+Ne6VrAmPiW6QqRhliDO+e82riI75ywSWrJb9TQw0+UkIQ2DlNr0u0TwCUTcQNN6aKnru ouVt3qoRlcD5MuRhLH+ttAcmNITMg7GQ6RQajWrSKuKFrt6iuDbjgO2cnaTrLbNBBKPTG4oF D6kX8Zea0KvVBagBsaC1CDTDQQMxYBPDBSlqYCb/b2x7KHTvTAHUBSsBRL6MKz8wwruDodTM 4E4ToV9URl4aE/msBZ4GLTtEmUHBh4/AYwk6ACYByYKyx5r3PDG0iHnJ8bV0OeyQ9ujfgBBP B2t4oASNnIOeGEEcQ2rjzsFNBFNPCKMBEACm7Xqafb1Dp1nDl06aw/3O9ixWsGMv1Uhfd2B6 it6wh1HDCn9HpekgouR2HLMvdd3Y//GG89irEasjzENZPsK82PS0bvkxxIHRFm0pikF4ljIb 6tca2sxFr/H7CCtWYZjZzPgnOPtnagN0qVVyEM7L5f7KjGb1/o5EDkVR2SVSSjrlmNdTL2Rd zaPqrBoxuR/y/n856deWqS1ZssOpqwKhxT1IVlF6S47CjFJ3+fiHNjkljLfxzDyQXwXCNoZn BKcW9PvAMf6W1DGASoXtsMg4HHzZ5fW+vnjzvWiC4pXrcP7Ivfxx5pB+nGiOfOY+/VSUlW/9 GdzPlOIc1bGyKc6tGREH5lErmeoJZ5k7E9cMJx+xzuDItvnZbf6RuH5fg3QsljQy8jLlr4S6 8YwxlObySJ5K+suPRzZOG2+kq77RJVqAgZXp3Zdvdaov4a5J3H8pxzjj0yZ2JZlndM4X7Msr P5tfxy1WvV4Km6QeFAsjcF5gM+wWl+mf2qrlp3dRwniG1vkLsnQugQ4oNUrx0ahwOSm9p6kM CIiTITo+W7O9KEE9XCb4vV0ejmLlgdDV8ASVUekeTJkmRIBnz0fa4pa1vbtZoi6/LlIdAEEt PY6p3hgkLLtr2GRodOW/Y3vPRd9+rJHq/tLIfwc58ZhQKmRcgrhtlnuTGTmyUqGSiMNfpwAR AQABwsFfBBgBAgAJBQJTTwijAhsMAAoJEAL1yD+ydue64BgP/33QKczgAvSdj9XTC14wZCGE U8ygZwkkyNf021iNMj+o0dpLU48PIhHIMTXlM2aiiZlPWgKVlDRjlYuc9EZqGgbOOuR/pNYA JX9vaqszyE34JzXBL9DBKUuAui8z8GcxRcz49/xtzzP0kH3OQbBIqZWuMRxKEpRptRT0wzBL O31ygf4FRxs68jvPCuZjTGKELIo656/Hmk17cmjoBAJK7JHfqdGkDXk5tneeHCkB411p9WJU vMO2EqsHjobjuFm89hI0pSxlUoiTL0Nuk9Edemjw70W4anGNyaQtBq+qu1RdjUPBvoJec7y/ EXJtoGxq9Y+tmm22xwApSiIOyMwUi9A1iLjQLmngLeUdsHyrEWTbEYHd2sAM2sqKoZRyBDSv ejRvZD6zwkY/9nRqXt02H1quVOP42xlkwOQU6gxm93o/bxd7S5tEA359Sli5gZRaucpNQkwd KLQdCvFdksD270r4jU/rwR2R/Ubi+txfy0dk2wGBjl1xpSf0Lbl/KMR5TQntELfLR4etizLq Xpd2byn96Ivi8C8u9zJruXTueHH8vt7gJ1oax3yKRGU5o2eipCRiKZ0s/T7fvkdq+8beg9ku fDO4SAgJMIl6H5awliCY2zQvLHysS/Wb8QuB09hmhLZ4AifdHyF1J5qeePEhgTA+BaUbiUZf i4aIXCH3Wv6K Organization: ARM Ltd. Message-ID: <22687572-becf-7b4e-9759-cfba44677a1d@arm.com> Date: Mon, 1 Jun 2020 11:14:59 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 MIME-Version: 1.0 In-Reply-To: <48afb8bb-a22a-54df-7751-55b7b84c3c88@arm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On 28/05/2020 14:30, André Przywara wrote: Hi, > On 28/05/2020 03:48, Guenter Roeck wrote: > > Hi Guenter, > >> On Wed, May 13, 2020 at 11:30:00AM +0100, Andre Przywara wrote: >>> The devicetree compiler complains when DT nodes without a reg property >>> live inside a (simple) bus node: >>> Warning (simple_bus_reg): Node /bus@8000000/motherboard-bus/refclk32khz >>> missing or empty reg/ranges property >>> >>> Move the fixed clocks, the fixed regulator, the leds and the config bus >>> subtree to the root node, since they do not depend on any busses. >>> >>> Signed-off-by: Andre Przywara >> >> This patch results in tracebacks when booting the vexpress-a15 machine >> with vexpress-v2p-ca15-tc1 devicetree file in qemu. Reverting it as well >> as the subsequent patches affecting the same file (to avoid revert >> conflicts) fixes the problem. > > Many thanks for the heads up! I was able to reproduce it here. On the > first glance it looks like the UART is probed before the clocks now, > because the traversal of the changed DT leads to a different probe > order. I will look into how to fix this. Turned out to be a bit more complicated: The arm,vexpress,config-bus driver walks up the device tree to find a arm,vexpress,site property [1]. With this patch the first parent node with that property it finds is now the root node, with the wrong site ID (0xf instead of 0x0). So it queries the wrong clocks (those IDs are actually reserved there), and QEMU reports back "0", consequently [2]. Finding a clock frequency in the range of [0, 0] won't get very far. Possible solutions are: 1) Just keep the mcc and its children at where it is in mainline right now, so *partly* reverting this patch. This has the problem of still producing a dtc warning, so kind of defeats the purpose of this patch. 2) Add a "arm,vexpress,site = <0>;" line to the "mcc" node itself. Works, but looks somewhat dodgy, as the mcc node should really be a child of the motherboard node, and we should not hack around this. 3) Dig deeper and fix the DT in a way that makes dtc happy. Might involve (dummy?) ranges or reg properties. My gut feeling is that arm,vexpress-sysreg,func should really have been "reg" in the first place, but that's too late to change now, anyway. I will post 2) as a fix if 3) turns out to be not feasible. Cheers, Andre [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/bus/vexpress-config.c#n46 [2] https://git.qemu.org/?p=qemu.git;a=blob;f=hw/arm/vexpress.c;hb=HEAD#l404 > > Cheers, > Andre > >> >> Guenter >> >> --- >> [ 12.744248] ------------[ cut here ]------------ >> [ 12.744562] WARNING: CPU: 0 PID: 20 at drivers/tty/serial/serial_core.c:471 uart_get_baud_rate+0x100/0x154 >> [ 12.744607] Modules linked in: >> [ 12.744785] CPU: 0 PID: 20 Comm: kworker/0:1 Not tainted 5.7.0-rc7-next-20200526 #1 >> [ 12.744818] Hardware name: ARM-Versatile Express >> [ 12.745021] Workqueue: events amba_deferred_retry_func >> [ 12.745155] [] (unwind_backtrace) from [] (show_stack+0x10/0x14) >> [ 12.745206] [] (show_stack) from [] (dump_stack+0xc8/0xdc) >> [ 12.745239] [] (dump_stack) from [] (__warn+0xdc/0xf4) >> [ 12.745270] [] (__warn) from [] (warn_slowpath_fmt+0xb0/0xb8) >> [ 12.745302] [] (warn_slowpath_fmt) from [] (uart_get_baud_rate+0x100/0x154) >> [ 12.745336] [] (uart_get_baud_rate) from [] (pl011_set_termios+0x48/0x32c) >> [ 12.745367] [] (pl011_set_termios) from [] (uart_set_options+0x124/0x164) >> [ 12.745404] [] (uart_set_options) from [] (pl011_console_setup+0x214/0x230) >> [ 12.745438] [] (pl011_console_setup) from [] (try_enable_new_console+0x98/0x138) >> [ 12.745469] [] (try_enable_new_console) from [] (register_console+0xe8/0x304) >> [ 12.745499] [] (register_console) from [] (uart_add_one_port+0x4c0/0x504) >> [ 12.745529] [] (uart_add_one_port) from [] (pl011_register_port+0x5c/0xac) >> [ 12.745568] [] (pl011_register_port) from [] (amba_probe+0x9c/0x110) >> [ 12.745602] [] (amba_probe) from [] (really_probe+0x218/0x348) >> [ 12.745632] [] (really_probe) from [] (driver_probe_device+0x5c/0xb4) >> [ 12.745662] [] (driver_probe_device) from [] (bus_for_each_drv+0x58/0xb8) >> [ 12.745692] [] (bus_for_each_drv) from [] (__device_attach+0xd4/0x140) >> [ 12.745721] [] (__device_attach) from [] (bus_probe_device+0x88/0x90) >> [ 12.745751] [] (bus_probe_device) from [] (device_add+0x3d4/0x6e8) >> [ 12.745782] [] (device_add) from [] (amba_device_try_add+0x50/0x2d4) >> [ 12.745812] [] (amba_device_try_add) from [] (amba_deferred_retry+0x3c/0x98) >> [ 12.745847] [] (amba_deferred_retry) from [] (amba_deferred_retry_func+0x8/0x40) >> [ 12.745881] [] (amba_deferred_retry_func) from [] (process_one_work+0x2b8/0x6e8) >> [ 12.745912] [] (process_one_work) from [] (worker_thread+0x44/0x540) >> [ 12.745942] [] (worker_thread) from [] (kthread+0x16c/0x178) >> [ 12.745973] [] (kthread) from [] (ret_from_fork+0x14/0x2c) >> [ 12.746041] Exception stack(0xc73abfb0 to 0xc73abff8) >> [ 12.746181] bfa0: 00000000 00000000 00000000 00000000 >> [ 12.746302] bfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 >> [ 12.746397] bfe0: 00000000 00000000 00000000 00000000 00000013 00000000 >> [ 12.746651] ---[ end trace 2a3f61da56bd8a49 ]--- >> >> --- >> # bad: [b0523c7b1c9d0edcd6c0fe6d2cb558a9ad5c60a8] Add linux-next specific files for 20200526 >> # good: [9cb1fd0efd195590b828b9b865421ad345a4a145] Linux 5.7-rc7 >> git bisect start 'next-20200526' 'v5.7-rc7' >> # bad: [0c7351ad83670964e48cb9a098ad732c1ecbf804] Merge remote-tracking branch 'crypto/master' >> git bisect bad 0c7351ad83670964e48cb9a098ad732c1ecbf804 >> # bad: [42e11d9b4682229fa7187d129758b8c382f8cd5d] Merge remote-tracking branch 'jc_docs/docs-next' >> git bisect bad 42e11d9b4682229fa7187d129758b8c382f8cd5d >> # bad: [ab6f501559e9efa687c711a781243cf6651a82d3] Merge remote-tracking branch 'm68k/for-next' >> git bisect bad ab6f501559e9efa687c711a781243cf6651a82d3 >> # bad: [44aaa516ca63b3ab2da8ae81e9c6a58656e6acb5] Merge branch 'arm/drivers' into for-next >> git bisect bad 44aaa516ca63b3ab2da8ae81e9c6a58656e6acb5 >> # good: [1cb00f8c3b36e6ae026fb58d1cd2ccd78b81aa9f] Merge tag 'qcom-arm64-for-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/qcom/linux into arm/dt >> git bisect good 1cb00f8c3b36e6ae026fb58d1cd2ccd78b81aa9f >> # bad: [ed0c25932fbfafdfe37e9633dee21770d3c5a306] Merge branch 'arm/defconfig' into for-next >> git bisect bad ed0c25932fbfafdfe37e9633dee21770d3c5a306 >> # bad: [9eddc06a3bc79402f50176703237ed045ae77b16] Merge branch 'mmp/fixes' into arm/dt >> git bisect bad 9eddc06a3bc79402f50176703237ed045ae77b16 >> # bad: [87b990ab62722a8a3cb0691107971ab1bd7bddb5] Merge tag 'mvebu-dt64-5.8-1' of git://git.infradead.org/linux-mvebu into arm/dt >> git bisect bad 87b990ab62722a8a3cb0691107971ab1bd7bddb5 >> # bad: [94cc3f1baabac5e5c4dcc6c2f070353f8315d0ee] arm64: dts: juno: Fix SCPI shared mem node name >> git bisect bad 94cc3f1baabac5e5c4dcc6c2f070353f8315d0ee >> # bad: [a78aee9e434932a500db36cc6d88daeff3745e9f] arm64: dts: juno: Fix GIC child nodes >> git bisect bad a78aee9e434932a500db36cc6d88daeff3745e9f >> # bad: [feebdc3f7950d7e44e914e821f6c04e58e292c74] arm64: dts: fvp: Move fixed clocks out of bus node >> git bisect bad feebdc3f7950d7e44e914e821f6c04e58e292c74 >> # good: [849bfc3dfc13cde6ec04fbcf32af553ded9f7ec3] arm64: dts: fvp: Move fixed devices out of bus node >> git bisect good 849bfc3dfc13cde6ec04fbcf32af553ded9f7ec3 >> # bad: [d9258898ad49cbb46caffe23af0d4f0b766e67a2] arm64: dts: vexpress: Move fixed devices out of bus node >> git bisect bad d9258898ad49cbb46caffe23af0d4f0b766e67a2 >> # first bad commit: [d9258898ad49cbb46caffe23af0d4f0b766e67a2] arm64: dts: vexpress: Move fixed devices out of bus node >> >