On 10/26/2015 02:15 PM, Wei Yang wrote:
PEs for VFs don't have primary bus. So they have to have their own reset
backend, which is used during EEH recovery. The patch implements the reset
backend for VF's PE by issuing FLR or AF FLR to the VFs, which are contained
in the PE.
[gwshan: changelog and code refactoring]
Signed-off-by: Wei Yang <weiy...@linux.vnet.ibm.com>
Acked-by: Gavin Shan <gws...@linux.vnet.ibm.com>
---
arch/powerpc/include/asm/eeh.h | 1 +
arch/powerpc/platforms/powernv/eeh-powernv.c | 134 ++++++++++++++++++++++++++-
2 files changed, 134 insertions(+), 1 deletion(-)
diff --git a/arch/powerpc/include/asm/eeh.h b/arch/powerpc/include/asm/eeh.h
index ec21f8f..331c856 100644
--- a/arch/powerpc/include/asm/eeh.h
+++ b/arch/powerpc/include/asm/eeh.h
@@ -136,6 +136,7 @@ struct eeh_dev {
int pcix_cap; /* Saved PCIx capability */
int pcie_cap; /* Saved PCIe capability */
int aer_cap; /* Saved AER capability */
+ int af_cap; /* Saved AF capability */
struct eeh_pe *pe; /* Associated PE */
struct list_head list; /* Form link list in the PE */
struct pci_controller *phb; /* Associated PHB */
diff --git a/arch/powerpc/platforms/powernv/eeh-powernv.c
b/arch/powerpc/platforms/powernv/eeh-powernv.c
index cfd55dd..017cd72 100644
--- a/arch/powerpc/platforms/powernv/eeh-powernv.c
+++ b/arch/powerpc/platforms/powernv/eeh-powernv.c
@@ -404,6 +404,7 @@ static void *pnv_eeh_probe(struct pci_dn *pdn, void *data)
edev->pcix_cap = pnv_eeh_find_cap(pdn, PCI_CAP_ID_PCIX);
edev->pcie_cap = pnv_eeh_find_cap(pdn, PCI_CAP_ID_EXP);
edev->aer_cap = pnv_eeh_find_ecap(pdn, PCI_EXT_CAP_ID_ERR);
+ edev->af_cap = pnv_eeh_find_cap(pdn, PCI_CAP_ID_AF);
if ((edev->class_code >> 8) == PCI_CLASS_BRIDGE_PCI) {
edev->mode |= EEH_DEV_BRIDGE;
if (edev->pcie_cap) {
@@ -893,6 +894,127 @@ static int pnv_eeh_bridge_reset(struct pci_dev *dev, int
option)
return 0;
}
+static void pnv_eeh_wait_for_pending(struct pci_dn *pdn, int pos,
+ u16 mask, bool af_flr_rst)
+{
+ struct eeh_dev *edev = pdn_to_eeh_dev(pdn);
+ int status, i;
+
+ /* Wait for Transaction Pending bit to be cleared */
+ for (i = 0; i < 4; i++) {
+ eeh_ops->read_config(pdn, pos, 2, &status);
gcc should have complained on using uninitialized @status here.
+ if (!(status & mask))
+ return;
+
+ msleep((1 << i) * 100);
+ }
+
+ pr_warn("%s: Pending transaction while issuing %s FLR to "
+ "%04x:%02x:%02x.%01x\n",
Do not wrap user-visible strings.
+ __func__, af_flr_rst ? "AF" : "",
+ edev->phb->global_number, pdn->busno,
+ PCI_SLOT(pdn->devfn), PCI_FUNC(pdn->devfn));
+}
+
+static int pnv_eeh_do_flr(struct pci_dn *pdn, int option)
+{
+ struct eeh_dev *edev = pdn_to_eeh_dev(pdn);
+ u32 reg;
+
+ if (!edev->pcie_cap)
+ return -ENOTTY;
Can pnv_eeh_do_flr() be really called on a non PCIe device, can we get that
far? WARN_ON_ONCE() may be?
+
+ eeh_ops->read_config(pdn, edev->pcie_cap + PCI_EXP_DEVCAP, 4, ®);
... and here about uninitialized @reg.
+ if (!(reg & PCI_EXP_DEVCAP_FLR))
+ return -ENOTTY;
+
+ switch (option) {
+ case EEH_RESET_HOT:
+ case EEH_RESET_FUNDAMENTAL:
+ pnv_eeh_wait_for_pending(pdn, edev->pcie_cap + PCI_EXP_DEVSTA,
+ PCI_EXP_DEVSTA_TRPND, false);
+ eeh_ops->read_config(pdn, edev->pcie_cap + PCI_EXP_DEVCTL,
+ 4, ®);
+ reg |= PCI_EXP_DEVCTL_BCR_FLR;
+ eeh_ops->write_config(pdn, edev->pcie_cap + PCI_EXP_DEVCTL,
+ 4, reg);
+ msleep(EEH_PE_RST_HOLD_TIME);
+ break;
+ case EEH_RESET_DEACTIVATE:
+ eeh_ops->read_config(pdn, edev->pcie_cap + PCI_EXP_DEVCTL,
+ 4, ®);
+ reg &= ~PCI_EXP_DEVCTL_BCR_FLR;
+ eeh_ops->write_config(pdn, edev->pcie_cap + PCI_EXP_DEVCTL,
+ 4, reg);
+ msleep(EEH_PE_RST_SETTLE_TIME);
+ break;
+ }
+
+ return 0;
+}
+
+static int pnv_eeh_do_af_flr(struct pci_dn *pdn, int option)
+{
+ struct eeh_dev *edev = pdn_to_eeh_dev(pdn);
+ u32 cap;
+
+ if (!edev->af_cap)
+ return -ENOTTY;
+
+ eeh_ops->read_config(pdn, edev->af_cap + PCI_AF_CAP, 1, &cap);
... and here about @cap.
+ if (!(cap & PCI_AF_CAP_TP) || !(cap & PCI_AF_CAP_FLR))
+ return -ENOTTY;
+
+ switch (option) {
+ case EEH_RESET_HOT:
+ case EEH_RESET_FUNDAMENTAL:
+ /*
+ * Wait for Transaction Pending bit to clear. A word-aligned
+ * test is used, so we use the conrol offset rather than status
+ * and shift the test bit to match.
Why word-aligned (not byte or double word)?
+ */
+ pnv_eeh_wait_for_pending(pdn, edev->af_cap + PCI_AF_CTRL,
+ PCI_AF_STATUS_TP << 8, true);
+ eeh_ops->write_config(pdn, edev->af_cap + PCI_AF_CTRL,
+ 1, PCI_AF_CTRL_FLR);
+ msleep(EEH_PE_RST_HOLD_TIME);
+ break;
+ case EEH_RESET_DEACTIVATE:
+ eeh_ops->write_config(pdn, edev->af_cap + PCI_AF_CTRL, 1, 0);
+ msleep(EEH_PE_RST_SETTLE_TIME);
btw there is an unrelated issue with EEH_PE_RST_SETTLE_TIME which is
defined as 1800 which is A LOT (+250ms from EEH_PE_RST_HOLD_TIME and for
some reason this is actually doubled so there is another reset somewhere).
Booting a guest with 63 VFs takes 6 minutes or so, is there a good reason
for such a huge timeout?
+ break;
+ }
+
+ return 0;
+}
+
+static int pnv_eeh_reset_vf(struct pci_dn *pdn, int option)
+{
+ int ret;
+
+ ret = pnv_eeh_do_flr(pdn, option);
+ if (ret != -ENOTTY)
+ return ret;
+
+ return pnv_eeh_do_af_flr(pdn, option);
+}
+
+static int pnv_eeh_vf_pe_reset(struct eeh_pe *pe, int option)
+{
+ struct eeh_dev *edev, *tmp;
+ struct pci_dn *pdn;
+ int ret;
+
+ eeh_pe_for_each_dev(pe, edev, tmp) {
+ pdn = eeh_dev_to_pdn(edev);
+ ret = pnv_eeh_reset_vf(pdn, option);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
void pnv_pci_reset_secondary_bus(struct pci_dev *dev)
{
struct pci_controller *hose;
@@ -968,7 +1090,9 @@ static int pnv_eeh_reset(struct eeh_pe *pe, int option)
}
bus = eeh_pe_bus_get(pe);
- if (pci_is_root_bus(bus) ||
+ if (pe->type & EEH_PE_VF)
+ ret = pnv_eeh_vf_pe_reset(pe, option);
+ else if (pci_is_root_bus(bus) ||
pci_is_root_bus(bus->parent))
ret = pnv_eeh_root_reset(hose, option);
else
@@ -1108,6 +1232,14 @@ static inline bool pnv_eeh_cfg_blocked(struct pci_dn
*pdn)
if (!edev || !edev->pe)
return false;
+ /*
+ * We will issue FLR or AF FLR to all VFs, which are contained
+ * in VF PE. It relies on the EEH PCI config accessors. So we
+ * can't block them during the window.
+ */
+ if ((edev->physfn) && (edev->pe->state & EEH_PE_RESET))
Extra braces around edev->physfn.
+ return false;
+
if (edev->pe->state & EEH_PE_CFG_BLOCKED)
return true;
--
Alexey
_______________________________________________
Linuxppc-dev mailing list
Linuxppc-dev@lists.ozlabs.org
https://lists.ozlabs.org/listinfo/linuxppc-dev
