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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id B0F79CAC5A7 for ; Mon, 22 Sep 2025 10:50:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=9FyE/0N1K3w7nr3vxYWKDBXg7DtluS3ho5RrT5Eoduw=; b=yOcHQIl2DskpNApuEYwSzQpThA uQ80bsFf44tWU2isdfSKcn+9lM9hw9wtUQ5KS30HOUyRdrfMUi9QjqwDjP/prZbQgMFTwiByxDlkS jRY8AoP+5il6aOP1H4iUPTueX5Iy834jp8Xkj2/o5mkjVxf4regg/XosZXB6se+jJXVfA4YClQAvb 60GYdqOmAg7lOcjLwgo0vI2UqO56TxML8TnM8/wT6UD5zlnMM6Lqv6hscPrUcwl2s95GKCTJLpsM+ iEB1D9PDPI0njoQljCn/1+l+xXqxA+6hCYtBwHNHAb0B3TfMKN7J51mA+xaFKL249hE2bIXy67VIK dcT29FBg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1v0e7O-0000000A7gJ-4AfR; Mon, 22 Sep 2025 10:50:02 +0000 Received: from sea.source.kernel.org ([2600:3c0a:e001:78e:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1v0e7M-0000000A7fI-41EG for linux-arm-kernel@lists.infradead.org; Mon, 22 Sep 2025 10:50:02 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id E87C244C43; Mon, 22 Sep 2025 10:49:58 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CACBFC4CEF0; Mon, 22 Sep 2025 10:49:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1758538198; bh=niid4/G+12MRj1IFs6hp4sxeglXjyvGTGDPW0mtxjKo=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=qn15K+BDQCMdtm8fPWDiC0Citf1LHeyLNl9kXRi5WJvwj2/1hIuCpVvsRxGMiSXBP X1RnlBTgKC6NFyFOYs4Ht4cTAKrG289MkmevTZU02K+unBfSI+7zLjm+dY9XGQsONM 7lfD8Fs5lCSaRp7iG/bLU3B9HB7R1UByh08z+VA/wlsghF52gImFrpJpqb4RfsYH6z ovVNgbPNhwvW+PRUn4J+Jhqq8YIvSn3QU6DmZ6Z3BDmodPCTMWLjh/1wNOI0WJbnIJ kTbDqYeC8arkwbeOcl8N4TP51f0ZjiM8O7wsFZv7XPtqlYd5qmvoh3IQU0LEZjc/fB yAne/WZgkp6yw== Date: Mon, 22 Sep 2025 12:49:53 +0200 From: Lorenzo Pieralisi To: Rob Herring Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, Sascha Bischoff , Marc Zyngier Subject: Re: [PATCH] of/irq: Add msi-parent check to of_msi_xlate() Message-ID: References: <20250916091858.257868-1-lpieralisi@kernel.org> <20250918135555.GA1540012-robh@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250918135555.GA1540012-robh@kernel.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250922_035001_039940_DB61D07F X-CRM114-Status: GOOD ( 41.06 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, Sep 18, 2025 at 08:55:55AM -0500, Rob Herring wrote: > On Tue, Sep 16, 2025 at 11:18:58AM +0200, Lorenzo Pieralisi wrote: > > In some legacy platforms the MSI controller for a PCI host > > bridge is identified by an msi-parent property whose phandle > > points at an MSI controller node with no #msi-cells property, > > that implicitly means #msi-cells == 0. > > > > For such platforms, mapping a device ID and retrieving the > > MSI controller node becomes simply a matter of checking > > whether in the device hierarchy there is an msi-parent property > > pointing at an MSI controller node with such characteristics. > > > > Add a helper function to of_msi_xlate() to check the msi-parent > > property in addition to msi-map and retrieve the MSI controller > > node (with a 1:1 ID deviceID-IN<->deviceID-OUT mapping) to > > provide support for deviceID mapping and MSI controller node > > retrieval for such platforms. > > Your line wrapping is a bit short. > > I had a look at who is parsing "msi-parent" themselves as that's > typically a recipe for doing it incorrectly ('interrupt-map' anyone). > Can we make iproc_pcie_msi_enable() use this? It's quite ugly reaching > into the GICv3 node... > > And perhaps irq-gic-its-msi-parent.c could use this? > > And looks like pcie-layerscape-gen4 is leaking a node reference... Hi Rob, given where we are in the development cycle and that technically this is a GICv5 fix I would send a patch to fix the issue in GICv5 MSI parent code in drivers/irqchip (yes, it is more code handling the msi-parent property scattered around) and then will resume this thread for v6.19 - starting the clean-up. This patch affects more platforms than GICv5 and I am not sure it is safe to rush it in. Thanks, Lorenzo > > > > Signed-off-by: Lorenzo Pieralisi > > Cc: Sascha Bischoff > > Cc: Rob Herring > > Cc: Marc Zyngier > > --- > > drivers/of/irq.c | 38 +++++++++++++++++++++++++++++++++++--- > > 1 file changed, 35 insertions(+), 3 deletions(-) > > > > diff --git a/drivers/of/irq.c b/drivers/of/irq.c > > index e7c12abd10ab..d0e2dfd0ee28 100644 > > --- a/drivers/of/irq.c > > +++ b/drivers/of/irq.c > > @@ -670,6 +670,35 @@ void __init of_irq_init(const struct of_device_id *matches) > > } > > } > > > > +static int of_check_msi_parent(struct device_node *dev_node, struct device_node **msi_node) > > +{ > > + struct of_phandle_args msi_spec; > > + int ret; > > + > > + /* > > + * An msi-parent phandle with a missing or == 0 #msi-cells > > + * property identifies a 1:1 ID translation mapping. > > + * > > + * Set the msi controller node if the firmware matches this > > + * condition. > > + */ > > + ret = of_parse_phandle_with_optional_args(dev_node, "msi-parent", "#msi-cells", > > + 0, &msi_spec); > > + if (!ret) { > > + if ((*msi_node && *msi_node != msi_spec.np) || msi_spec.args_count != 0) > > + ret = -EINVAL; > > + > > + if (!ret) { > > + /* Return with a node reference held */ > > + *msi_node = msi_spec.np; > > + return 0; > > + } > > + of_node_put(msi_spec.np); > > + } > > + > > + return ret; > > +} > > + > > /** > > * of_msi_xlate - map a MSI ID and find relevant MSI controller node > > * @dev: device for which the mapping is to be done. > > @@ -677,7 +706,7 @@ void __init of_irq_init(const struct of_device_id *matches) > > * @id_in: Device ID. > > * > > * Walk up the device hierarchy looking for devices with a "msi-map" > > - * property. If found, apply the mapping to @id_in. > > + * or "msi-parent" property. If found, apply the mapping to @id_in. > > * If @msi_np points to a non-NULL device node pointer, only entries targeting > > * that node will be matched; if it points to a NULL value, it will receive the > > * device node of the first matching target phandle, with a reference held. > > @@ -691,12 +720,15 @@ u32 of_msi_xlate(struct device *dev, struct device_node **msi_np, u32 id_in) > > > > /* > > * Walk up the device parent links looking for one with a > > - * "msi-map" property. > > + * "msi-map" or an "msi-parent" property. > > */ > > - for (parent_dev = dev; parent_dev; parent_dev = parent_dev->parent) > > + for (parent_dev = dev; parent_dev; parent_dev = parent_dev->parent) { > > if (!of_map_id(parent_dev->of_node, id_in, "msi-map", > > "msi-map-mask", msi_np, &id_out)) > > break; > > + if (!of_check_msi_parent(parent_dev->of_node, msi_np)) > > + break; > > + } > > return id_out; > > } > > > > -- > > 2.48.0 > >