[openib-general] [patch 02/45] IB/mthca: restore missing PCI registers after reset

[Adrian Bunk]

It seems this patch should also be included in the 2.6.16.x branch, or 
do I miss anything?

TIA
Adrian


On Mon, Jul 17, 2006 at 09:25:31AM -0700, Greg KH wrote:
> -stable review patch.  If anyone has any objections, please let us know.
> 
> ------------------
> mthca does not restore the following PCI-X/PCI Express registers after reset:
>   PCI-X device: PCI-X command register
>   PCI-X bridge: upstream and downstream split transaction registers
>   PCI Express : PCI Express device control and link control registers
> 
> This causes instability and/or bad performance on systems where one of
> these registers is set to a non-default value by BIOS.
> 
> Signed-off-by: Michael S. Tsirkin <mst at mellanox.co.il>
> Signed-off-by: Chris Wright <chrisw at sous-sol.org>
> Signed-off-by: Greg Kroah-Hartman <gregkh at suse.de>
> 
> ---
>  drivers/infiniband/hw/mthca/mthca_reset.c |   59 ++++++++++++++++++++++++++++++
>  1 file changed, 59 insertions(+)
> 
> --- linux-2.6.17.2.orig/drivers/infiniband/hw/mthca/mthca_reset.c
> +++ linux-2.6.17.2/drivers/infiniband/hw/mthca/mthca_reset.c
> @@ -49,6 +49,12 @@ int mthca_reset(struct mthca_dev *mdev)
>  	u32 *hca_header    = NULL;
>  	u32 *bridge_header = NULL;
>  	struct pci_dev *bridge = NULL;
> +	int bridge_pcix_cap = 0;
> +	int hca_pcie_cap = 0;
> +	int hca_pcix_cap = 0;
> +
> +	u16 devctl;
> +	u16 linkctl;
>  
>  #define MTHCA_RESET_OFFSET 0xf0010
>  #define MTHCA_RESET_VALUE  swab32(1)
> @@ -110,6 +116,9 @@ int mthca_reset(struct mthca_dev *mdev)
>  		}
>  	}
>  
> +	hca_pcix_cap = pci_find_capability(mdev->pdev, PCI_CAP_ID_PCIX);
> +	hca_pcie_cap = pci_find_capability(mdev->pdev, PCI_CAP_ID_EXP);
> +
>  	if (bridge) {
>  		bridge_header = kmalloc(256, GFP_KERNEL);
>  		if (!bridge_header) {
> @@ -129,6 +138,13 @@ int mthca_reset(struct mthca_dev *mdev)
>  				goto out;
>  			}
>  		}
> +		bridge_pcix_cap = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
> +		if (!bridge_pcix_cap) {
> +				err = -ENODEV;
> +				mthca_err(mdev, "Couldn't locate HCA bridge "
> +					  "PCI-X capability, aborting.\n");
> +				goto out;
> +		}
>  	}
>  
>  	/* actually hit reset */
> @@ -178,6 +194,20 @@ int mthca_reset(struct mthca_dev *mdev)
>  good:
>  	/* Now restore the PCI headers */
>  	if (bridge) {
> +		if (pci_write_config_dword(bridge, bridge_pcix_cap + 0x8,
> +				 bridge_header[(bridge_pcix_cap + 0x8) / 4])) {
> +			err = -ENODEV;
> +			mthca_err(mdev, "Couldn't restore HCA bridge Upstream "
> +				  "split transaction control, aborting.\n");
> +			goto out;
> +		}
> +		if (pci_write_config_dword(bridge, bridge_pcix_cap + 0xc,
> +				 bridge_header[(bridge_pcix_cap + 0xc) / 4])) {
> +			err = -ENODEV;
> +			mthca_err(mdev, "Couldn't restore HCA bridge Downstream "
> +				  "split transaction control, aborting.\n");
> +			goto out;
> +		}
>  		/*
>  		 * Bridge control register is at 0x3e, so we'll
>  		 * naturally restore it last in this loop.
> @@ -203,6 +233,35 @@ good:
>  		}
>  	}
>  
> +	if (hca_pcix_cap) {
> +		if (pci_write_config_dword(mdev->pdev, hca_pcix_cap,
> +				 hca_header[hca_pcix_cap / 4])) {
> +			err = -ENODEV;
> +			mthca_err(mdev, "Couldn't restore HCA PCI-X "
> +				  "command register, aborting.\n");
> +			goto out;
> +		}
> +	}
> +
> +	if (hca_pcie_cap) {
> +		devctl = hca_header[(hca_pcie_cap + PCI_EXP_DEVCTL) / 4];
> +		if (pci_write_config_word(mdev->pdev, hca_pcie_cap + PCI_EXP_DEVCTL,
> +					   devctl)) {
> +			err = -ENODEV;
> +			mthca_err(mdev, "Couldn't restore HCA PCI Express "
> +				  "Device Control register, aborting.\n");
> +			goto out;
> +		}
> +		linkctl = hca_header[(hca_pcie_cap + PCI_EXP_LNKCTL) / 4];
> +		if (pci_write_config_word(mdev->pdev, hca_pcie_cap + PCI_EXP_LNKCTL,
> +					   linkctl)) {
> +			err = -ENODEV;
> +			mthca_err(mdev, "Couldn't restore HCA PCI Express "
> +				  "Link control register, aborting.\n");
> +			goto out;
> +		}
> +	}
> +
>  	for (i = 0; i < 16; ++i) {
>  		if (i * 4 == PCI_COMMAND)
>  			continue;
> 
> --
> -
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo at vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/