Re: [PATCH v8 37/45] powerpc/powernv: Use firmware PCI slot reset infrastructure
From: Alexey Kardashevskiy <hidden>
Date: 2016-04-19 09:34:55
Also in:
linux-devicetree, linux-pci
On 02/17/2016 02:44 PM, Gavin Shan wrote:
quoted hunk ↗ jump to hunk
The skiboot firmware might provide the PCI slot reset capability which is identified by property "ibm,reset-by-firmware" on the PCI slot associated device node. This checks the property. If it exists, the reset request is routed to firmware. Otherwise, the reset is done by kernel as before. Signed-off-by: Gavin Shan <redacted> --- arch/powerpc/platforms/powernv/eeh-powernv.c | 41 +++++++++++++++++++++++++++- 1 file changed, 40 insertions(+), 1 deletion(-)diff --git a/arch/powerpc/platforms/powernv/eeh-powernv.c b/arch/powerpc/platforms/powernv/eeh-powernv.c index e23b063..c8a5217 100644 --- a/arch/powerpc/platforms/powernv/eeh-powernv.c +++ b/arch/powerpc/platforms/powernv/eeh-powernv.c@@ -789,7 +789,7 @@ static int pnv_eeh_root_reset(struct pci_controller *hose, int option) return ret; } -static int pnv_eeh_bridge_reset(struct pci_dev *dev, int option) +static int __pnv_eeh_bridge_reset(struct pci_dev *dev, int option) { struct pci_dn *pdn = pci_get_pdn_by_devfn(dev->bus, dev->devfn); struct eeh_dev *edev = pdn_to_eeh_dev(pdn);@@ -840,6 +840,45 @@ static int pnv_eeh_bridge_reset(struct pci_dev *dev, int option) return 0; } +static int pnv_eeh_bridge_reset(struct pci_dev *pdev, int option) +{ + struct pci_controller *hose; + struct pnv_phb *phb; + struct device_node *dn = pdev ? pci_device_to_OF_node(pdev) : NULL; + uint64_t id = (0x1ul << 60);
What is this 1<<60 for?
+ uint8_t scope;
+ int64_t rc;
+
+ /*
+ * If the firmware can't handle it, we will issue hot reset
+ * on the secondary bus despite the requested reset type.
+ */
+ if (!dn || !of_get_property(dn, "ibm,reset-by-firmware", NULL))
+ return __pnv_eeh_bridge_reset(pdev, option);
+
+ /* The firmware can handle the request */
+ switch (option) {
+ case EEH_RESET_HOT:
+ scope = OPAL_RESET_PCI_HOT;
+ break;
+ case EEH_RESET_FUNDAMENTAL:
+ scope = OPAL_RESET_PCI_FUNDAMENTAL;
+ break;
+ case EEH_RESET_DEACTIVATE:
+ return 0;
+ default:
+ dev_warn(&pdev->dev, "%s: Unsupported reset %d\n",
+ __func__, option);Can the userspace trigger this case (via VFIO-EEH) and flood dmesg?
+ return -EINVAL;
+ }
+
+ hose = pci_bus_to_host(pdev->bus);
+ phb = hose->private_data;
+ id |= (pdev->bus->number << 24) | (pdev->devfn << 16) | phb->opal_id;
+ rc = opal_pci_reset(id, scope, OPAL_ASSERT_RESET);
+ return pnv_pci_poll(id, rc, NULL);
+}
+
static int pnv_pci_dev_reset_type(struct pci_dev *pdev, void *data)
{
int *freset = data;-- Alexey