From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vidya Sagar Subject: Re: [PATCH V7 02/15] PCI: Disable MSI for Tegra194 root port Date: Tue, 21 May 2019 22:17:26 +0530 Message-ID: References: <20190517123846.3708-1-vidyas@nvidia.com> <20190517123846.3708-3-vidyas@nvidia.com> <20190521102729.GB29166@ulmo> Mime-Version: 1.0 Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20190521102729.GB29166@ulmo> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Thierry Reding Cc: lorenzo.pieralisi@arm.com, bhelgaas@google.com, robh+dt@kernel.org, mark.rutland@arm.com, jonathanh@nvidia.com, kishon@ti.com, catalin.marinas@arm.com, will.deacon@arm.com, jingoohan1@gmail.com, gustavo.pimentel@synopsys.com, mperttunen@nvidia.com, linux-pci@vger.kernel.org, devicetree@vger.kernel.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kthota@nvidia.com, mmaddireddy@nvidia.com, sagar.tv@gmail.com List-Id: devicetree@vger.kernel.org On 5/21/2019 3:57 PM, Thierry Reding wrote: > On Fri, May 17, 2019 at 06:08:33PM +0530, Vidya Sagar wrote: >> Tegra194 rootports don't generate MSI interrupts for PME events and hence >> MSI needs to be disabled for them to avoid root ports service drivers >> registering their respective ISRs with MSI interrupt. >> >> Signed-off-by: Vidya Sagar >> --- >> Changes since [v6]: >> * This is a new patch >> >> drivers/pci/quirks.c | 14 ++++++++++++++ >> 1 file changed, 14 insertions(+) >> >> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c >> index 0f16acc323c6..28f9a0380df5 100644 >> --- a/drivers/pci/quirks.c >> +++ b/drivers/pci/quirks.c >> @@ -2592,6 +2592,20 @@ DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_NVIDIA, >> PCI_DEVICE_ID_NVIDIA_NVENET_15, >> nvenet_msi_disable); >> >> +/* >> + * Tegra194's PCIe root ports don't generate MSI interrupts for PME events >> + * instead legacy interrupts are generated. Hence, to avoid service drivers >> + * registering their respective ISRs for MSIs, need to disable MSI interrupts >> + * for root ports. >> + */ >> +static void disable_tegra194_rp_msi(struct pci_dev *dev) >> +{ >> + dev->no_msi = 1; >> +} >> +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_NVIDIA, 0x1ad0, disable_tegra194_rp_msi); >> +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_NVIDIA, 0x1ad1, disable_tegra194_rp_msi); >> +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_NVIDIA, 0x1ad2, disable_tegra194_rp_msi); >> + > > Later functions in this file seem to use a more consistent naming > pattern, according to which the name for this would become: > > pci_quirk_nvidia_tegra194_disable_rp_msi > > Might be worth considering making this consistent. > > This could also be moved to the DWC driver to restrict this to where it > is needed. In either case, this seems like a good solution, so: > > Reviewed-by: Thierry Reding > Ok. I'll move it to DWC driver along with name change for the quirk API.