From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3D86927FD6E; Thu, 18 Sep 2025 15:21:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758208885; cv=none; b=QeMifoZM9aiH8Kdq5whgYaRSEAjNKburzp9ME+NwJOPgWuxAdQ1KrSRBhFL0ln2J1JhfykJvWvUTdf9XSN1iaQzl+wc0C1kQfDp9Eh1eq6nKOdML+BtdKUbCqSZCVUVXYhVjmItFefOpSqsDj+eJDnh/eh710cSg1kW3DPWgjd4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758208885; c=relaxed/simple; bh=7/PcDCApIZDlkgzvsXPVNcvnV9qW0ZVXMY2lmhDLV2g=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=QJxuWU0D8CriKJANo2nB3zBSP5Po74f8vBBQUM+L5791mUagBAztv23N4FXE65BdE49VvdA79NMCZjBd5sppbQ0vWOrkSmynobnvrlONXhPbB2mJXfvZiy4IdkwY9isNsdY58kDmNOLDlm4DP0cStJUgNqsX8xJFFmX2j6IJ3Mc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=PtvKWjPe; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="PtvKWjPe" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4786BC4CEE7; Thu, 18 Sep 2025 15:21:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1758208885; bh=7/PcDCApIZDlkgzvsXPVNcvnV9qW0ZVXMY2lmhDLV2g=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=PtvKWjPeuOqZewrc1jvLPZENqzSs3NQI9uGuhxJy8CL9PFwJ2F9KXKAh4WLxaxByF TbwKpbHP5xZiC+a90zgvrkrk41BXYnPdF8zsIzW9iTNK6srHz4gnJlM93aN49AFT6P LYKxXLxIpe1VJxD5feXdvZvPQDfmHd+dErzpsGnqyDyEgUiJIoAOPErwri6cswMZx0 JmKEHYoiTXdOre5XfoqXJuAvFpA4ScNpoGft8cnVPC4EIBBlAIu6jVXOVrO8vrTtFV Ipace+FhpGJ7cQZNu19SL1v+EZFOWZrxcYNsNd2u0KXYYxoZL5xGif0ObfGTfFp1d0 DwnV7lyBBiy+Q== Date: Thu, 18 Sep 2025 17:21:20 +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> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250918135555.GA1540012-robh@kernel.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... I am not sure I get what you mean here. Possibly iproc_pcie_msi_enable() can reuse this patch's code if I extend it and make it a global function, yes and somehow use that function to carry out the check for an msi-parent property with no #msi-cells property or an #msi-cells == 0. Don't get what GICv3 node has to do with that though, sorry. > And perhaps irq-gic-its-msi-parent.c could use this? Yes and I have to fix leaks there too (and there are other of_phandle_with_args() calls in the kernel that don't put the args.np pointer on success - though not to retrieve msi-parent). > > And looks like pcie-layerscape-gen4 is leaking a node reference... It looks like it is in good company I am afraid :( 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 > >