Re: [PATCH 3/4]: [PCI]: Add quirk for devices which disable MSIwhen INTX_DISABLE is set.

From: Michael Ellerman
Date: Wed Oct 24 2007 - 01:30:37 EST


On Tue, 2007-10-23 at 19:53 -0700, David Miller wrote:
> A reasonably common problem with some devices is that they will
> disable MSI generation when the INTX_DISABLE bit is set in the
> PCI_COMMAND register.
>
> Quirk this explicitly, guarding the pci_intx() calls in msi.c with
> this quirk indication.
>
> The first entries for this quirk are for 5714 and 5780 Tigon3 chips,
> and thus we can remove the workaround code from the tg3.c driver.
>
> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>

> diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
> index 87e0161..a8dd18c 100644
> --- a/drivers/pci/msi.c
> +++ b/drivers/pci/msi.c
> @@ -237,7 +237,8 @@ static void __pci_restore_msi_state(struct pci_dev *dev)
> entry = get_irq_msi(dev->irq);
> pos = entry->msi_attrib.pos;
>
> - pci_intx(dev, 0); /* disable intx */
> + if (!(dev->dev_flags & PCI_DEV_FLAGS_MSI_INTX_DISABLE_BUG))
> + pci_intx(dev, 0); /* disable intx */
> msi_set_enable(dev, 0);
> write_msi_msg(dev->irq, &entry->msg);
> if (entry->msi_attrib.maskbit)
> @@ -260,7 +261,8 @@ static void __pci_restore_msix_state(struct pci_dev *dev)
> return;
>
> /* route the table */
> - pci_intx(dev, 0); /* disable intx */
> + if (!(dev->dev_flags & PCI_DEV_FLAGS_MSI_INTX_DISABLE_BUG))
> + pci_intx(dev, 0); /* disable intx */
> msix_set_enable(dev, 0);
>
> list_for_each_entry(entry, &dev->msi_list, list) {
> @@ -343,7 +345,8 @@ static int msi_capability_init(struct pci_dev *dev)
> }
>
> /* Set MSI enabled bits */
> - pci_intx(dev, 0); /* disable intx */
> + if (!(dev->dev_flags & PCI_DEV_FLAGS_MSI_INTX_DISABLE_BUG))
> + pci_intx(dev, 0); /* disable intx */
> msi_set_enable(dev, 1);
> dev->msi_enabled = 1;
>
> @@ -433,7 +436,8 @@ static int msix_capability_init(struct pci_dev *dev,
> i++;
> }
> /* Set MSI-X enabled bits */
> - pci_intx(dev, 0); /* disable intx */
> + if (!(dev->dev_flags & PCI_DEV_FLAGS_MSI_INTX_DISABLE_BUG))
> + pci_intx(dev, 0); /* disable intx */
> msix_set_enable(dev, 1);
> dev->msix_enabled = 1;
>
> @@ -528,7 +532,8 @@ void pci_disable_msi(struct pci_dev* dev)
> return;
>
> msi_set_enable(dev, 0);
> - pci_intx(dev, 1); /* enable intx */
> + if (!(dev->dev_flags & PCI_DEV_FLAGS_MSI_INTX_DISABLE_BUG))
> + pci_intx(dev, 1); /* enable intx */
> dev->msi_enabled = 0;
>
> BUG_ON(list_empty(&dev->msi_list));
> @@ -640,7 +645,8 @@ void pci_disable_msix(struct pci_dev* dev)
> return;
>
> msix_set_enable(dev, 0);
> - pci_intx(dev, 1); /* enable intx */
> + if (!(dev->dev_flags & PCI_DEV_FLAGS_MSI_INTX_DISABLE_BUG))
> + pci_intx(dev, 1); /* enable intx */
> dev->msix_enabled = 0;
>
> msix_free_all_irqs(dev);


That looks like 6 hunks doing exactly the same thing? What about
creating a pci_intx_quirked() (or something) that checks the flag and
then does/or does not call pci_intx().

cheers

--
Michael Ellerman
OzLabs, IBM Australia Development Lab

wwweb: http://michael.ellerman.id.au
phone: +61 2 6212 1183 (tie line 70 21183)

We do not inherit the earth from our ancestors,
we borrow it from our children. - S.M.A.R.T Person

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