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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EEF3BC4167B for ; Mon, 27 Nov 2023 19:01:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232695AbjK0TBW (ORCPT ); Mon, 27 Nov 2023 14:01:22 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33680 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229531AbjK0TBU (ORCPT ); Mon, 27 Nov 2023 14:01:20 -0500 Received: from mx01.omp.ru (mx01.omp.ru [90.154.21.10]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C3B35D4D; Mon, 27 Nov 2023 11:01:25 -0800 (PST) Received: from [192.168.1.103] (31.173.82.188) by msexch01.omp.ru (10.188.4.12) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.2.1258.12; Mon, 27 Nov 2023 22:01:17 +0300 Subject: Re: [PATCH 13/13] net: ravb: Add runtime PM support To: Geert Uytterhoeven , claudiu beznea CC: , , , , , , , , , , , , , , , Claudiu Beznea References: <20231120084606.4083194-1-claudiu.beznea.uj@bp.renesas.com> <20231120084606.4083194-14-claudiu.beznea.uj@bp.renesas.com> <04cb07fe-cccc-774a-f14d-763ce7ae7b07@omp.ru> <9af21eb9-6fe1-de3a-f2eb-4493778ebb32@omp.ru> From: Sergey Shtylyov Organization: Open Mobile Platform Message-ID: Date: Mon, 27 Nov 2023 22:01:16 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [31.173.82.188] X-ClientProxiedBy: msexch01.omp.ru (10.188.4.12) To msexch01.omp.ru (10.188.4.12) X-KSE-ServerInfo: msexch01.omp.ru, 9 X-KSE-AntiSpam-Interceptor-Info: scan successful X-KSE-AntiSpam-Version: 6.0.0, Database issued on: 11/27/2023 18:45:24 X-KSE-AntiSpam-Status: KAS_STATUS_NOT_DETECTED X-KSE-AntiSpam-Method: none X-KSE-AntiSpam-Rate: 59 X-KSE-AntiSpam-Info: Lua profiles 181629 [Nov 27 2023] X-KSE-AntiSpam-Info: Version: 6.0.0.2 X-KSE-AntiSpam-Info: Envelope from: s.shtylyov@omp.ru X-KSE-AntiSpam-Info: LuaCore: 5 0.3.5 98d108ddd984cca1d7e65e595eac546a62b0144b X-KSE-AntiSpam-Info: {rep_avail} X-KSE-AntiSpam-Info: {Tracking_all_Bitcoin, text} X-KSE-AntiSpam-Info: {Tracking_from_domain_doesnt_match_to} X-KSE-AntiSpam-Info: {relay has no DNS name} X-KSE-AntiSpam-Info: {SMTP from is not routable} X-KSE-AntiSpam-Info: {Found in DNSBL: 31.173.82.188 in (user) b.barracudacentral.org} X-KSE-AntiSpam-Info: omp.ru:7.1.1;d41d8cd98f00b204e9800998ecf8427e.com:7.1.1;127.0.0.199:7.1.2 X-KSE-AntiSpam-Info: ApMailHostAddress: 31.173.82.188 X-KSE-AntiSpam-Info: {DNS response errors} X-KSE-AntiSpam-Info: Rate: 59 X-KSE-AntiSpam-Info: Status: not_detected X-KSE-AntiSpam-Info: Method: none X-KSE-AntiSpam-Info: Auth:dmarc=temperror header.from=omp.ru;spf=temperror smtp.mailfrom=omp.ru;dkim=none X-KSE-Antiphishing-Info: Clean X-KSE-Antiphishing-ScanningType: Heuristic X-KSE-Antiphishing-Method: None X-KSE-Antiphishing-Bases: 11/27/2023 18:53:00 X-KSE-Antivirus-Interceptor-Info: scan successful X-KSE-Antivirus-Info: Clean, bases: 11/27/2023 4:12:00 PM X-KSE-Attachment-Filter-Triggered-Rules: Clean X-KSE-Attachment-Filter-Triggered-Filters: Clean X-KSE-BulkMessagesFiltering-Scan-Result: InTheLimit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/27/23 5:05 PM, Geert Uytterhoeven wrote: [...] >>>>>> From: Claudiu Beznea >>>>> >>>>>> RZ/G3S supports enabling/disabling clocks for its modules (including >>>>>> Ethernet module). For this commit adds runtime PM support which >>>>>> relies on PM domain to enable/disable Ethernet clocks. >>>>> >>>>> That's not exactly something new in RZ/G3S. The ravb driver has unconditional >>>>> RPM calls already in the probe() and remove() methods... >>>>> And the sh_eth driver >>>>> has RPM support since 2009... >>>>> >>>>>> At the end of probe ravb_pm_runtime_put() is called which will turn >>>>> >>>>> I'd suggest a shorter name, like ravb_rpm_put() but (looking at this function) >>>>>> off the Ethernet clocks (if no other request arrives at the driver). >>>>>> After that if the interface is brought up (though ravb_open()) then >>>>>> the clocks remain enabled until interface is brought down (operation >>>>>> done though ravb_close()). >>>>>> >>>>>> If any request arrives to the driver while the interface is down the >>>>>> clocks are enabled to serve the request and then disabled. >>>>>> >>>>>> Signed-off-by: Claudiu Beznea [...] > Sergey: does sh_eth.c really reinitialize the hardware completely after > pm_runtime_get_sync()? Well, even with the original Magnus' commit that added the RPM support (bcd5149ded6b2edbf3732fa1483600a716b1cba6) it wasn't so -- sh_eth_open() indeed seemed to re-init everything (but not TSU!) but sh_eth_get_stats() surely didn't (the RPM calls there have been removed since); other RPM "wrappers" have been added to the driver methods since -- which also don't init anything... thus the comment in sh_eth_runtime_nop(() seems to be wrong from the very start... [...] > Gr{oetje,eeting}s, > > Geert MBR, Sergey