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=-11.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=unavailable 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 9D7D0C43612 for ; Wed, 2 Jan 2019 01:28:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6BB3C218A4 for ; Wed, 2 Jan 2019 01:28:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1546392493; bh=hjrUtNXCE4m20teCOVhOxvQ3bn9KxyuOFTRLDwbwEDg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=ZlhAvj6pw+HkREPY3t+SDwNtNGv4cdiDuKZLrDHb2RjvnOcOk2rEvvh7STXrHvqcO PKmbmUNJtvHtfNjGa1u7WOtdNNXNsTgoGlxWUHlTkQ4tMmsWnYz0suDPcQJlexFrDs X5BePOejOOw+ZTsYCsyatRB+9AQTs6uBHiRwm6Nk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728207AbfABB2M (ORCPT ); Tue, 1 Jan 2019 20:28:12 -0500 Received: from mail.kernel.org ([198.145.29.99]:46350 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728162AbfABB2M (ORCPT ); Tue, 1 Jan 2019 20:28:12 -0500 Received: from localhost (unknown [69.71.4.100]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D03C42171F; Wed, 2 Jan 2019 01:28:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1546392491; bh=hjrUtNXCE4m20teCOVhOxvQ3bn9KxyuOFTRLDwbwEDg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=1RGs6CXj2CIrNcJ6qzohel+sWH3k61Xg7ierw69ZZz+aheurP4lorSh0tiHH64j/g 7kuLE+LAKW/sn57ay7ve3yWBitHDI9geR2yesE2TfNYjkD1dKn+R/MLBjtoK/zD3eW TbheBijN1yVfanTY4QdTtgsTIX6vQZDDku4oE/5M= Date: Tue, 1 Jan 2019 19:28:09 -0600 From: Bjorn Helgaas To: Richard Zhu Cc: "lorenzo.pieralisi@arm.com" , "l.stach@pengutronix.de" , "andrew.smirnov@gmail.com" , "TheSven73@googlemail.com" , "linux-pci@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" Subject: Re: [v6] PCI: imx: make msi work without CONFIG_PCIEPORTBUS=y Message-ID: <20190102012809.GB126384@google.com> References: <1545365708-13086-1-git-send-email-hongxing.zhu@nxp.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1545365708-13086-1-git-send-email-hongxing.zhu@nxp.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Dec 21, 2018 at 04:33:38AM +0000, Richard Zhu wrote: > The MSI Enable bit in the MSI Capability (PCIe r4.0, sec 7.7.1.2) > controls whether a Function can request service using MSI. > > i.MX6 Root Ports implement the MSI Capability and may use MSI to > request service for events like PME, hotplug, AER, etc. In > addition, on i.MX6, the MSI Enable bit controls delivery of MSI > interrupts from components below the Root Port. > > Prior to commit f3fdfc4ac3a2 ("PCI: Remove host driver Kconfig selection > of CONFIG_PCIEPORTBUS"), enabling CONFIG_PCI_IMX6 automatically also > enabled CONFIG_PCIEPORTBUS, and when portdrv claimed the Root Ports, > it set the MSI Enable bit so it could use PME, hotplug, AER, etc. > As a side effect, that also enabled delivery of MSI interrupts from > downstream components. > > After f3fdfc4ac3a2, the imx6q-pcie driver can operate without > portdrv, but that means imx6q-pcie must set the MSI Enable bit > itself if downstream components use MSI. > > Fixes: f3fdfc4ac3a2 ("PCI: Remove host driver Kconfig selection of CONFIG_PCIEPORTBUS") > > Signed-off-by: Richard Zhu > Reviewed-by: Lucas Stach > Tested-by: Sven Van Asbroeck > Acked-by: Lorenzo Pieralisi Applied with Trent's tested-by to pci/imx6 for v4.21. > --- > Changes v1 -> v2: > * Assert the MSI_EN unconditionally when MSI is supported. > Changes v2 -> v3: > * Remove the IS_ENABLED(CONFIG_PCI_MSI) since the driver depends on > PCI_MSI_IRQ_DOMAIN > * Extended with a check for pci_msi_enabled() to see if the user > explicitly want legacy IRQs > Changes v3 -> v4: > * Refer to Bjorn's comments, refine the subject and commit log and change > the PCI_MSI_CAP to PCIE_RC_IMX6_MSI_CAP. > Changes v4 -> v5: > * Correct one spell mistake from PCIE_RC_MSI_IMX6_CAP to > PCIE_RC_IMX6_MSI_CAP. > Changes v5 -> v6: > * Update with Bjorn's commit. > * One "commit" added in "Prior to f3fdfc4ac3a2" refer to the complain of > checkpatch.pl. > --- > drivers/pci/controller/dwc/pci-imx6.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c > index e563ca9..73542dd 100644 > --- a/drivers/pci/controller/dwc/pci-imx6.c > +++ b/drivers/pci/controller/dwc/pci-imx6.c > @@ -82,6 +82,7 @@ struct imx6_pcie { > #define PHY_PLL_LOCK_WAIT_USLEEP_MAX 200 > > /* PCIe Root Complex registers (memory-mapped) */ > +#define PCIE_RC_IMX6_MSI_CAP 0x50 > #define PCIE_RC_LCR 0x7c > #define PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN1 0x1 > #define PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN2 0x2 > @@ -999,6 +1000,7 @@ static int imx6_pcie_probe(struct platform_device *pdev) > struct resource *dbi_base; > struct device_node *node = dev->of_node; > int ret; > + u16 val; > > imx6_pcie = devm_kzalloc(dev, sizeof(*imx6_pcie), GFP_KERNEL); > if (!imx6_pcie) > @@ -1149,6 +1151,14 @@ static int imx6_pcie_probe(struct platform_device *pdev) > if (ret < 0) > return ret; > > + if (pci_msi_enabled()) { > + val = dw_pcie_readw_dbi(pci, PCIE_RC_IMX6_MSI_CAP + > + PCI_MSI_FLAGS); > + val |= PCI_MSI_FLAGS_ENABLE; > + dw_pcie_writew_dbi(pci, PCIE_RC_IMX6_MSI_CAP + > + PCI_MSI_FLAGS, val); > + } > + > return 0; > } > > -- > 2.7.4 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel