powerpc/pseries: fix EEH recovery of some IOV devices

EEH recovery currently fails on pSeries for some IOV capable PCI
devices, if CONFIG_PCI_IOV is on and the hypervisor doesn't provide
certain device tree properties for the device. (Found on an IOV
capable device using the ipr driver.)

Recovery fails in pci_enable_resources() at the check on r->parent,
because r->flags is set and r->parent is not.  This state is due to
sriov_init() setting the start, end and flags members of the IOV BARs
but the parent not being set later in
pseries_pci_fixup_iov_resources(), because the
"ibm,open-sriov-vf-bar-info" property is missing.

Correct this by zeroing the resource flags for IOV BARs when they
can't be configured (this is the same method used by sriov_init() and
__pci_read_base()).

VFs cleared this way can't be enabled later, because that requires
another device tree property, "ibm,number-of-configurable-vfs" as well
as support for the RTAS function "ibm_map_pes". These are all part of
hypervisor support for IOV and it seems unlikely that a hypervisor
would ever partially, but not fully, support it. (None are currently
provided by QEMU/KVM.)

Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Reviewed-by: Bryant G. Ly <bryantly@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Sam Bobroff 2018-07-30 11:59:14 +10:00 committed by Michael Ellerman
parent e0da99123f
commit b87b9cf493
1 changed files with 17 additions and 8 deletions

View File

@ -647,6 +647,15 @@ void of_pci_parse_iov_addrs(struct pci_dev *dev, const int *indexes)
}
}
static void pseries_disable_sriov_resources(struct pci_dev *pdev)
{
int i;
pci_warn(pdev, "No hypervisor support for SR-IOV on this device, IOV BARs disabled.\n");
for (i = 0; i < PCI_SRIOV_NUM_BARS; i++)
pdev->resource[i + PCI_IOV_RESOURCES].flags = 0;
}
static void pseries_pci_fixup_resources(struct pci_dev *pdev)
{
const int *indexes;
@ -654,10 +663,10 @@ static void pseries_pci_fixup_resources(struct pci_dev *pdev)
/*Firmware must support open sriov otherwise dont configure*/
indexes = of_get_property(dn, "ibm,open-sriov-vf-bar-info", NULL);
if (!indexes)
return;
/* Assign the addresses from device tree*/
of_pci_set_vf_bar_size(pdev, indexes);
if (indexes)
of_pci_set_vf_bar_size(pdev, indexes);
else
pseries_disable_sriov_resources(pdev);
}
static void pseries_pci_fixup_iov_resources(struct pci_dev *pdev)
@ -669,10 +678,10 @@ static void pseries_pci_fixup_iov_resources(struct pci_dev *pdev)
return;
/*Firmware must support open sriov otherwise dont configure*/
indexes = of_get_property(dn, "ibm,open-sriov-vf-bar-info", NULL);
if (!indexes)
return;
/* Assign the addresses from device tree*/
of_pci_parse_iov_addrs(pdev, indexes);
if (indexes)
of_pci_parse_iov_addrs(pdev, indexes);
else
pseries_disable_sriov_resources(pdev);
}
static resource_size_t pseries_pci_iov_resource_alignment(struct pci_dev *pdev,