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=-0.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no 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 7B370C433DB for ; Sat, 30 Jan 2021 01:56:18 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D8D0764E0A for ; Sat, 30 Jan 2021 01:56:17 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D8D0764E0A Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=mail.ee Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:List-Subscribe:List-Help:List-Post:List-Archive:List-Unsubscribe :List-Id:To:Subject:From:Date:Message-ID:MIME-Version:Reply-To:Cc:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:In-Reply-To:References:List-Owner; bh=tJh1EJd8MUZGVAZ4VW0ZRseV8jx2kNnQzqvTlo9/7dU=; b=INqUFFoVLPOef604JSbTkCo2pT Fokx9IRSBl2N2huW7LCLdXdVHMm5rY+CJFqWlIiaQziXPquoUYoIQZLYEt7JQE9p4QPYECg0zNuKR Wwnu4eNbBLdt8N5Z+KkNkmOlsiJtCjdiKOekvKnVx/q4sI21gR1fKjzH0bYdsKLUP7komtQ8jb4WI kZrKm3ZDpMHO+MSOX5p5Fgxpmaa/lJjD4zM2zFhOU7lPSfvmO4tSVIQjM4vxend5f7RNs5WHt0Y3C PEPVJIAnxDFMaecWK4IQMQzadFY19/FQA0Sjw2b3l3RYB71J6WNMwg8fV6OK5mK/faX2Il767kagO n6Uibtrg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1l5fUc-0004n0-TH; Sat, 30 Jan 2021 01:56:06 +0000 Received: from eu-shark1.inbox.eu ([195.216.236.81]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1l5fUZ-0004mR-Vf for linux-mediatek@lists.infradead.org; Sat, 30 Jan 2021 01:56:05 +0000 Received: by eu-shark1.inbox.eu (Postfix, from userid 2004) id 2B2FB6C0074C; Sat, 30 Jan 2021 03:55:58 +0200 (EET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=mail.ee; s=20150108; t=1611971758; bh=qjBuWTSfP8xq+dGVw7irquA1cYBpkKO8XE7q/8a4XoM=; h=Date:From:Subject:To; b=e4743ab+zD3NTJWMRG6qncpPwe/3uHnUx5l8yc0EWAKUSMvGsJTow4buVH6sRfSwH HhanzE8jgNI/xT1WOu89qcXzgsXNNEDH3kG1KZqW+zL7z4a3lKTynt+/Ea24QfBAej oixrnB18j1Nv1IdCM7cVXSr+AQtV1JmeylVUsqSg= Received: from eu-w4.inbox.eu (eu-w4 [127.0.0.1]) by eu-shark1-in.inbox.eu (Postfix) with ESMTP id D951A6C00700 for ; Sat, 30 Jan 2021 03:55:57 +0200 (EET) MIME-Version: 1.0 X-HTTP-USER-AGENT: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/89.0.4346.0 Safari/537.36 Edg/89.0.731.0 Message-ID: <1611971757.6014bcadd6ece@posti.mail.ee> Date: Sat, 30 Jan 2021 03:55:57 +0200 From: "Boris Lysov" Subject: [RFC] Question about contributing mt6577 support but SMP doesn't work To: linux-mediatek@lists.infradead.org User-Agent: Mail.ee Webmail X-ESPOL: +dBm4e9TfTq68yDTPBPAcGMr01Q+UZib54XO3RxclX34OSqAeksRI3S6/XAUPnG5okZr7UE26UBKC2W2QFu3n7jIZlHMuQYc X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210129_205604_253683_7A4B8FF2 X-CRM114-Status: UNSURE ( 7.40 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org Hello! I'm working on bringing the initial support for mt6577 into the mainline kernel. I've got the base set of hardware to work: timers, and few interrupt controllers, and all 4 UARTs, and PL310 cache controller. My test device boots mainline successfully and runs stable! I'm having issues with getting SMP to work. mt6577 is a dual-core SoC, and broken SMP means half of the processing power is unavailable. I tried to use the existing SMP bring-up code located in arch/arm/mach-mediatek/platsmp.c , but it didn't work albeit all specified registers were correct. I also tried porting the SMP init code from the downstream mediatek kernel, but it never worked either. My question is: could I still contribute my device support patches despite literally 50% of the CPU not working? I *strongly* doubt they would be accepted because of it, but on the other hand devices with mt6577 (and other compatible SoCs like mt8317) are still able to boot and run bare mainline kernel on a single core. I ran out of ideas on how to make that pesky 2nd core come up online with my poor knowledge. _______________________________________________ Linux-mediatek mailing list Linux-mediatek@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-mediatek