| Message ID | 20240726135903.1255825-1-s-vadapalli@ti.com (mailing list archive) |
|---|---|
| State | Under Review |
| Delegated to: | Manivannan Sadhasivam |
| Headers | show |
| Series | [v2] PCI: j721e: Disable INTx mapping and swizzling | expand |
On Fri, Jul 26, 2024 at 07:29:03PM +0530, Siddharth Vadapalli wrote: > Since the configuration of INTx (Legacy Interrupt) is not supported, set > the .map_irq and .swizzle_irq callbacks to NULL. This fixes the error: > of_irq_parse_pci: failed with rc=-22 > when the pcieport driver attempts to setup INTx for the Host Bridge via > "pci_assign_irq()". The device-tree node of the Host Bridge doesn't > contain Legacy Interrupts. As a result, Legacy Interrupts are searched for > in the MSI Interrupt Parent of the Host Bridge with the help of > "of_irq_parse_raw()". Since the MSI Interrupt Parent of the Host Bridge > uses 3 interrupt cells while Legacy Interrupts only use 1, the search > for Legacy Interrupts is terminated prematurely by the "of_irq_parse_raw()" > function with the -EINVAL error code (rc=-22). > > Fixes: f3e25911a430 ("PCI: j721e: Add TI J721E PCIe driver") > Cc: stable@vger.kernel.org > Reported-by: Andrew Halaney <ahalaney@redhat.com> > Tested-by: Andrew Halaney <ahalaney@redhat.com> > Signed-off-by: Siddharth Vadapalli <s-vadapalli@ti.com> TBH, I'm not comfortable with this change. Because, the INTx compatibility _should_ come from the platform description (in this case DT) and not the driver. The default map_irq() function is supposed to check the existence of INTx and correctly report it. In this case the issue is, the platform is not supporting INTx, but of_irq_parse_pci() reports a dubious error: 'of_irq_parse_pci: failed with rc=-22' instead of the actual error: `of_irq_parse_pci: no interrupt-map found, INTx interrupts not available' So I would say that the fix is in of_irq_parse_pci() implementation. of_irq_parse_pci() is supposed to find whether the PCIe controller is supporting INTx or not by parsing the 'interrupt-{map/extended}' properties till host bridge/controller node. But this API along with of_irq_parse_raw(), just walks up the tree till the top level interrupt controller and checks for INTx, which just feels wrong (that's why you are getting -EINVAL because of #interrupt-cells mismatch). I looked into the implementation over the weekend, but I'm not quite sure how to fix it though. Rob, perhaps you have any idea? - Mani > --- > > Hello, > > This patch is based on commit > 1722389b0d86 Merge tag 'net-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net > of Mainline Linux. > > v1: > https://lore.kernel.org/r/20240724065048.285838-1-s-vadapalli@ti.com > Changes since v1: > - Added "Cc: stable@vger.kernel.org" in the commit message. > - Based on Bjorn's feedback at: > https://lore.kernel.org/r/20240724162304.GA802428@bhelgaas/ > the $subject and commit message have been updated. Additionally, the > comment in the driver has also been updated to specify "INTx" instead of > "Legacy Interrupts". > - Collected Tested-by tag from Andrew Halaney <ahalaney@redhat.com>: > https://lore.kernel.org/r/vj6vtjphpmqv6hcblaalr2m4bwjujjwvom6ca4bjdzcmgazyaa@436unrb2lav7/ > > Patch has been tested on J721e-EVM and J784S4-EVM. > > Regards, > Siddharth. > > drivers/pci/controller/cadence/pci-j721e.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/pci/controller/cadence/pci-j721e.c b/drivers/pci/controller/cadence/pci-j721e.c > index 85718246016b..eaa6cfeb03c7 100644 > --- a/drivers/pci/controller/cadence/pci-j721e.c > +++ b/drivers/pci/controller/cadence/pci-j721e.c > @@ -417,6 +417,10 @@ static int j721e_pcie_probe(struct platform_device *pdev) > if (!bridge) > return -ENOMEM; > > + /* INTx is not supported */ > + bridge->map_irq = NULL; > + bridge->swizzle_irq = NULL; > + > if (!data->byte_access_allowed) > bridge->ops = &cdns_ti_pcie_host_ops; > rc = pci_host_bridge_priv(bridge); > -- > 2.40.1 >
diff --git a/drivers/pci/controller/cadence/pci-j721e.c b/drivers/pci/controller/cadence/pci-j721e.c index 85718246016b..eaa6cfeb03c7 100644 --- a/drivers/pci/controller/cadence/pci-j721e.c +++ b/drivers/pci/controller/cadence/pci-j721e.c @@ -417,6 +417,10 @@ static int j721e_pcie_probe(struct platform_device *pdev) if (!bridge) return -ENOMEM; + /* INTx is not supported */ + bridge->map_irq = NULL; + bridge->swizzle_irq = NULL; + if (!data->byte_access_allowed) bridge->ops = &cdns_ti_pcie_host_ops; rc = pci_host_bridge_priv(bridge);
Since the configuration of INTx (Legacy Interrupt) is not supported, set the .map_irq and .swizzle_irq callbacks to NULL. This fixes the error: of_irq_parse_pci: failed with rc=-22 when the pcieport driver attempts to setup INTx for the Host Bridge via "pci_assign_irq()". The device-tree node of the Host Bridge doesn't contain Legacy Interrupts. As a result, Legacy Interrupts are searched for in the MSI Interrupt Parent of the Host Bridge with the help of "of_irq_parse_raw()". Since the MSI Interrupt Parent of the Host Bridge uses 3 interrupt cells while Legacy Interrupts only use 1, the search for Legacy Interrupts is terminated prematurely by the "of_irq_parse_raw()" function with the -EINVAL error code (rc=-22). Fixes: f3e25911a430 ("PCI: j721e: Add TI J721E PCIe driver") Cc: stable@vger.kernel.org Reported-by: Andrew Halaney <ahalaney@redhat.com> Tested-by: Andrew Halaney <ahalaney@redhat.com> Signed-off-by: Siddharth Vadapalli <s-vadapalli@ti.com> --- Hello, This patch is based on commit 1722389b0d86 Merge tag 'net-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net of Mainline Linux. v1: https://lore.kernel.org/r/20240724065048.285838-1-s-vadapalli@ti.com Changes since v1: - Added "Cc: stable@vger.kernel.org" in the commit message. - Based on Bjorn's feedback at: https://lore.kernel.org/r/20240724162304.GA802428@bhelgaas/ the $subject and commit message have been updated. Additionally, the comment in the driver has also been updated to specify "INTx" instead of "Legacy Interrupts". - Collected Tested-by tag from Andrew Halaney <ahalaney@redhat.com>: https://lore.kernel.org/r/vj6vtjphpmqv6hcblaalr2m4bwjujjwvom6ca4bjdzcmgazyaa@436unrb2lav7/ Patch has been tested on J721e-EVM and J784S4-EVM. Regards, Siddharth. drivers/pci/controller/cadence/pci-j721e.c | 4 ++++ 1 file changed, 4 insertions(+)