From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Mon, 20 May 2019 15:37:31 -0500 From: Bjorn Helgaas Subject: Re: [PATCH V4 20/28] PCI: tegra: Use legacy IRQ for port service drivers Message-ID: <20190520203731.GA54609@google.com> References: <20190516055307.25737-1-mmaddireddy@nvidia.com> <20190516055307.25737-21-mmaddireddy@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190516055307.25737-21-mmaddireddy@nvidia.com> To: Manikanta Maddireddy Cc: thierry.reding@gmail.com, robh+dt@kernel.org, mark.rutland@arm.com, jonathanh@nvidia.com, lorenzo.pieralisi@arm.com, vidyas@nvidia.com, linux-tegra@vger.kernel.org, linux-pci@vger.kernel.org, devicetree@vger.kernel.org List-ID: On Thu, May 16, 2019 at 11:22:59AM +0530, Manikanta Maddireddy wrote: > Tegra signals PCIe services like AER, PME, etc. over legacy IRQ line. > By default, service drivers register interrupt routine over MSI IRQ line. > Use pcie_pme_disable_msi() function to disable MSI for service drivers. I think this device is not quite spec-compliant: https://lore.kernel.org/linux-pci/20190520175729.GC49425@google.com/ and you should work around this with a quirk that sets pdev->no_msi so we don't use MSI for it at all. > PME and AER interrupts registered to MSI without this change, > cat /proc/interrupts | grep -i pci > 36: 21 0 0 0 0 0 GICv2 104 Level PCIE > 37: 35 0 0 0 0 0 GICv2 105 Level Tegra PCIe MSI > 76: 0 0 0 0 0 0 Tegra PCIe MSI 0 Edge PCIe PME, aerdrv, PCIe BW notif > > PME and AER interrupts registered to legacy IRQ with this change, > cat /proc/interrupts | grep -i pci > 36: 33 0 0 0 0 0 GICv2 104 Level PCIE, PCIe PME, aerdrv, PCIe BW notif > 37: 52 0 0 0 0 0 GICv2 105 Level Tegra PCIe MSI > > Signed-off-by: Manikanta Maddireddy > Acked-by: Thierry Reding > --- > V4: No change > > V3: Corrected typo in commit log > > V2: No change > > drivers/pci/controller/pci-tegra.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/pci/controller/pci-tegra.c b/drivers/pci/controller/pci-tegra.c > index ac57c5badd9b..0024bc42b400 100644 > --- a/drivers/pci/controller/pci-tegra.c > +++ b/drivers/pci/controller/pci-tegra.c > @@ -41,6 +41,7 @@ > #include > > #include "../pci.h" > +#include "../pcie/portdrv.h" > > #define INT_PCI_MSI_NR (8 * 32) > > @@ -2725,6 +2726,9 @@ static int tegra_pcie_probe(struct platform_device *pdev) > goto put_resources; > } > > + /* Switch to legacy IRQ for PCIe services like AER, PME*/ > + pcie_pme_disable_msi(); > + > pm_runtime_enable(pcie->dev); > err = pm_runtime_get_sync(pcie->dev); > if (err) { > -- > 2.17.1 >