Commit afd24ece authored by Ram Pai's avatar Ram Pai Committed by Jesse Barnes
Browse files

PCI: delay configuration of SRIOV capability 



The SRIOV capability, namely page size and total_vfs of a device are
configured during enumeration phase of the device.  This can potentially
interfere with the PCI operations of the platform, if the IOV capability
of the device is not enabled.

The following patch postpones the configuration of the IOV capability of
the device to a later point, when the IOV capability is explicitly
enabled by the device driver.

The patch is tested on x86 and power platform.

Tested-by: default avatarDonald Dutile <ddutile@redhat.com>
Signed-off-by: default avatarRam Pai <linuxram@us.ibm.com>
Signed-off-by: default avatarJesse Barnes <jbarnes@virtuousgeek.org>
parent 79cc9601

drivers/pci/iov.c

+2 −2
Original line number Diff line number Diff line
@@ -347,6 +347,8 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn) 
			return rc;

	}



	pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz);



	iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE;

	pci_cfg_access_lock(dev);

	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
@@ -452,7 +454,6 @@ static int sriov_init(struct pci_dev *dev, int pos) 


found:

	pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, ctrl);

	pci_write_config_word(dev, pos + PCI_SRIOV_NUM_VF, total);

	pci_read_config_word(dev, pos + PCI_SRIOV_VF_OFFSET, &offset);

	pci_read_config_word(dev, pos + PCI_SRIOV_VF_STRIDE, &stride);

	if (!offset || (total > 1 && !stride))
@@ -465,7 +466,6 @@ found: 
		return -EIO;



	pgsz &= ~(pgsz - 1);

	pci_write_config_dword(dev, pos + PCI_SRIOV_SYS_PGSIZE, pgsz);



	nres = 0;

	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {

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