Messages in this thread | | | Date | Wed, 20 Feb 2013 08:57:27 -0800 | Subject | Re: [PATCH] pci: do not try to assign irq 255 | From | Yinghai Lu <> |
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On Tue, Feb 19, 2013 at 11:58 PM, Hannes Reinecke <hare@suse.de> wrote: >> > Apparently this device is meant to use MSI _only_ so the BIOS developer > didn't feel the need to assign an INTx here. > > According to PCI-3.0, section 6.8 (Message Signalled Interrupts): >> It is recommended that devices implement interrupt pins to >> provide compatibility in systems that do not support MSI >> (devices default to interrupt pins). However, it is expected >> that the need for interrupt pins will diminish over time. >> Devices that do not support interrupt pins due to pin >> constraints (rely on polling for device service) may implement >> messages to increase performance without adding additional pins. > >> Therefore, system configuration software must not assume that a >> message capable device has an interrupt pin. > > Which sounds to me as if the implementation is valid...
it seems you mess pin with interrupt line.
current code: unsigned char irq;
pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq); dev->pin = irq; if (irq) pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq); dev->irq = irq;
so if the device does not have interrupt pin implemented, pin should be zero. and pin and irq in dev should be all 0.
Thanks
Yinghai
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