Re: [git patch] improve INTx toggle for PCI MSI

[Andrew Morton <akpm@osdl.org>]

On Thu, 7 Dec 2006 17:58:12 -0500
Jeff Garzik <jeff@garzik.org> wrote:

> 
> "it boots" on ICH7 at least.

That's a rave review ;)

> Please pull from 'intx' branch of
> master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/misc-2.6.git intx
> 
> to receive the following updates:
> 
>  drivers/pci/msi.c |   12 ++++--------
>  1 files changed, 4 insertions(+), 8 deletions(-)
> 
> Jeff Garzik:
>       PCI MSI: always toggle legacy-INTx-enable bit upon MSI entry/exit

Why?

> diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
> index 9fc9a34..c2828a3 100644
> --- a/drivers/pci/msi.c
> +++ b/drivers/pci/msi.c
> @@ -255,10 +255,8 @@ static void enable_msi_mode(struct pci_d
>  		pci_write_config_word(dev, msi_control_reg(pos), control);
>  		dev->msix_enabled = 1;
>  	}
> -    	if (pci_find_capability(dev, PCI_CAP_ID_EXP)) {
> -		/* PCI Express Endpoint device detected */
> -		pci_intx(dev, 0);  /* disable intx */
> -	}
> +
> +	pci_intx(dev, 0);  /* disable intx */
>  }
>  
>  void disable_msi_mode(struct pci_dev *dev, int pos, int type)
> @@ -276,10 +274,8 @@ void disable_msi_mode(struct pci_dev *de
>  		pci_write_config_word(dev, msi_control_reg(pos), control);
>  		dev->msix_enabled = 0;
>  	}
> -    	if (pci_find_capability(dev, PCI_CAP_ID_EXP)) {
> -		/* PCI Express Endpoint device detected */
> -		pci_intx(dev, 1);  /* enable intx */
> -	}
> +
> +	pci_intx(dev, 1);  /* enable intx */
>  }
>  
>  static int msi_lookup_irq(struct pci_dev *dev, int type)