Messages in this thread | | | Date | Sat, 4 Jun 2005 03:23:48 -0400 | From | Dave Jones <> | Subject | Re: pci_enable_msi() for everyone? |
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On Sat, Jun 04, 2005 at 12:18:03AM -0700, Greg KH wrote: > On Sat, Jun 04, 2005 at 01:05:37AM -0600, Grant Grundler wrote: > > On Fri, Jun 03, 2005 at 11:48:21PM -0700, Greg KH wrote: > > > > One complication is some drivers will want to register a different > > > > IRQ handler depending on if MSI is enabled or not. > > > > > > That's fine, they can always check the device capabilities and do that. > > > > Can you be more specific? > > Maybe a short chunk of psuedo code? > > Hm, here's a possible function to do it (typed into my email client, not > compiled, no warranties, etc...): > > /* returns 1 if device is in MSI mode, 0 otherwise */ > int pci_in_msi_mode(struct pci_dev *dev) > { > int pos; > u16 control; > > pos = pci_find_capability(dev, PCI_CAP_ID_MSI); > if (!pos) > return 0; > pci_read_config_word(dev, msi_control_reg(pos), &control); > if (control & PCI_MSI_FLAGS_ENABLE); > return 1; > return 0; > }
What if MSI support has been disabled in the bridge due to some quirk (like the recent AMD 8111 quirk) ? Maybe the above function should check pci_msi_enable as well ?
Dave
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