From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ryder Lee Subject: Re: [PATCH 1/2] of_pci_irq: add a check to fallback to standard device tree parsing Date: Fri, 16 Mar 2018 08:58:09 +0800 Message-ID: <1521161889.13458.1.camel@mtkswgap22> References: <31c765c53e85e41bfc001d110d69e46c9967f4e7.1516961656.git.ryder.lee@mediatek.com> <20180315174329.GB22176@e107981-ln.cambridge.arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20180315174329.GB22176@e107981-ln.cambridge.arm.com> Sender: linux-kernel-owner@vger.kernel.org To: Lorenzo Pieralisi Cc: Arnd Bergmann , Rob Herring , Bjorn Helgaas , Frank Rowand , Benjamin Herrenschmidt , linux-pci@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org List-Id: devicetree@vger.kernel.org On Thu, 2018-03-15 at 17:43 +0000, Lorenzo Pieralisi wrote: > On Wed, Jan 31, 2018 at 03:41:49PM +0800, Ryder Lee wrote: > > A root complex usually consist of a host bridge and multiple P2P bridges, > > and someone may express that in the form of a root node with many subnodes > > and list all four interrupts for each slot (child node) in the root node > > like this: > > > > pcie-controller { > > ... > > interrupt-map-mask = <0xf800 0 0 7>; > > interrupt-map = <0x0000 0 0 {INTx} &{interrupt parent} ...> > > 0x0800 0 0 {INTx} &{interrupt parent} ...>; > > > > pcie@0,0 { > > reg = <0x0000 0 0 0 0>; > > ... > > }; > > > > pcie@1,0 { > > reg = <0x0800 0 0 0 0>; > > ... > > }; > > }; > > > > As shown above, we'd like to propagate IRQs from a root port to the devices > > in the hierarchy below it in this way. However, it seems that the current > > parser couldn't handle such cases and will get something unexpected below: > > > > pcieport 0000:00:01.0: assign IRQ: got 213 > > igb 0000:01:00.0: assign IRQ: got 212 > > > > There is a device which is connected to 2nd slot, but the port doesn't share > > the same IRQ with its downstream devices. The problem here is that, if the > > loop found a P2P bridge, it wouldn't check whether the reg property exists > > in ppnode or not but just pass the subordinate devfn to of_irq_parse_raw(), > > thus the subsequent flow couldn't correctly resolve them. > > > > Fix this by adding a check to fallback to standard device tree parsing. > > > > Signed-off-by: Ryder Lee > > --- > > Please refer to the previous discussion thread: https://patchwork.ozlabs.org/patch/829108/ > > --- > > drivers/of/of_pci_irq.c | 14 ++++++++++++-- > > 1 file changed, 12 insertions(+), 2 deletions(-) > > Hi Ryder, > > from the thread discussion I gather I can drop this series from the PCI > queue and you will update the DT as agreed with Ben, that looks like > the most reasonable solution to the problem you are facing, please > let me know if there is anything I am missing. > > Thanks, > Lorenzo > Yes, please drop the series. Thanks