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 A2DB4C43334 for ; Tue, 21 Jun 2022 21:24:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1356250AbiFUVYo (ORCPT ); Tue, 21 Jun 2022 17:24:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37852 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1356266AbiFUVYW (ORCPT ); Tue, 21 Jun 2022 17:24:22 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5DFA13335F; Tue, 21 Jun 2022 14:16:08 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 93D9AB817F3; Tue, 21 Jun 2022 21:16:07 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id F2DEFC3411C; Tue, 21 Jun 2022 21:16:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1655846166; bh=uxyToZbWIGGW5FOK4A4PzHLsSHFLbJnwMxvPmTsgLfM=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=Zz1jDoAXuMUMYOtpnPZ70gkon3l2BKsmAl7BkI0xy0TZ4JAOKVKWrcDioplrJBtHZ 30zXxnvwvcr+r4R/T++MrzBk0UHrfmtx27WlCKsnV2lSsuNXRIvP0t0SF1Lk9pGp+D 1VET9V9pUoPy7BuxtoFm3m8vMBwwFUZeOgubDE3oUdGBXg7YLhOwKRPgAqaJTKvEGS GRRyGcHcG3/zrKRC6bogLoyfT6w80VgsdthBJ33Te+eeQgMynyVmQw5rhpLpb4VmmL 8g155SbpShYgGUxgNIU/Kz2SasLrinrDv4xpDh17PapgxixUpyN25Pc7uDP0ZW5/db 9MRuijoR3Ue7A== Date: Tue, 21 Jun 2022 16:16:04 -0500 From: Bjorn Helgaas To: Dmitry Baryshkov Cc: Robert Marko , svarbanov@mm-sol.com, agross@kernel.org, bjorn.andersson@linaro.org, lpieralisi@kernel.org, robh@kernel.org, kw@linux.com, bhelgaas@google.com, p.zabel@pengutronix.de, jingoohan1@gmail.com, linux-pci@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, johan+linaro@kernel.org Subject: Re: [PATCH v2] PCI: qcom: fix IPQ8074 Gen2 support Message-ID: <20220621211604.GA1334281@bhelgaas> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Tue, Jun 21, 2022 at 11:45:12PM +0300, Dmitry Baryshkov wrote: > On Tue, 21 Jun 2022 at 23:32, Bjorn Helgaas wrote: > > On Tue, Jun 21, 2022 at 01:23:30PM +0200, Robert Marko wrote: > > > IPQ8074 has one Gen2 and one Gen3 port, currently the Gen2 port will > > > cause the system to hang as its using DBI registers in the .init > > > and those are only accesible after phy_power_on(). > > > > Is the fact that IPQ8074 has both a Gen2 and a Gen3 port relevant to > > this patch? I don't see the connection. > > > > I see that qcom_pcie_host_init() does: > > > > qcom_pcie_host_init > > pcie->cfg->ops->init(pcie) > > phy_power_on(pcie->phy) > > pcie->cfg->ops->post_init(pcie) > > > > and that you're moving DBI register accesses from > > qcom_pcie_init_2_3_3() to qcom_pcie_post_init_2_3_3(). > > > > But I also see DBI register accesses in other .init() functions: > > > > qcom_pcie_init_2_1_0 > > qcom_pcie_init_1_0_0 (oddly out of order) > > qcom_pcie_init_2_3_2 > > qcom_pcie_init_2_4_0 > > > > Why do these accesses not need to be moved? I assume it's because > > pcie->phy is an optional PHY and phy_power_on() does nothing on those > > controllers? > > > > Whatever the reason, I think the DBI accesses should be done > > consistently in .post_init(). I see that Dmitry's previous patches > > removed all those .post_init() functions, but I think the consistency > > is worth having. > > > > Perhaps we could reorder the patches so this patch comes first, moves > > the DBI accesses into .post_init(), then Dmitry's patches could be > > rebased on top to drop the clock handling? > > I don't think there is a need to reorder patches. My patches do not > remove support for post_init(), they drop the callbacks code. Thus one > can reinstate necessary code back. There's not a *need* to reorder them, but I think it would make the patches smaller and more readable because we wouldn't be removing and then re-adding the functions.