[POWERPC] EEH: support MMIO enable recovery step
Update to the PowerPC PCI error recovery code.
Add code to enable MMIO if a device driver reports that it is capable
of recovering on its own. One anticipated use of this having a device
driver enable MMIO so that it can take a register dump, which might
then be followed by the device driver requesting a full reset.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/platforms/pseries/eeh_driver.c b/arch/powerpc/platforms/pseries/eeh_driver.c
index 045cd7a..c2bc990 100644
--- a/arch/powerpc/platforms/pseries/eeh_driver.c
+++ b/arch/powerpc/platforms/pseries/eeh_driver.c
@@ -100,14 +100,38 @@
PCI_DN(dn)->eeh_mode |= EEH_MODE_IRQ_DISABLED;
disable_irq_nosync(dev->irq);
}
- if (!driver->err_handler)
- return;
- if (!driver->err_handler->error_detected)
+ if (!driver->err_handler ||
+ !driver->err_handler->error_detected)
return;
rc = driver->err_handler->error_detected (dev, pci_channel_io_frozen);
if (*res == PCI_ERS_RESULT_NONE) *res = rc;
- if (*res == PCI_ERS_RESULT_NEED_RESET) return;
+ if (*res == PCI_ERS_RESULT_DISCONNECT &&
+ rc == PCI_ERS_RESULT_NEED_RESET) *res = rc;
+}
+
+/**
+ * eeh_report_mmio_enabled - tell drivers that MMIO has been enabled
+ *
+ * Report an EEH error to each device driver, collect up and
+ * merge the device driver responses. Cumulative response
+ * passed back in "userdata".
+ */
+
+static void eeh_report_mmio_enabled(struct pci_dev *dev, void *userdata)
+{
+ enum pci_ers_result rc, *res = userdata;
+ struct pci_driver *driver = dev->driver;
+
+ // dev->error_state = pci_channel_mmio_enabled;
+
+ if (!driver ||
+ !driver->err_handler ||
+ !driver->err_handler->mmio_enabled)
+ return;
+
+ rc = driver->err_handler->mmio_enabled (dev);
+ if (*res == PCI_ERS_RESULT_NONE) *res = rc;
if (*res == PCI_ERS_RESULT_DISCONNECT &&
rc == PCI_ERS_RESULT_NEED_RESET) *res = rc;
}
@@ -118,6 +142,7 @@
static void eeh_report_reset(struct pci_dev *dev, void *userdata)
{
+ enum pci_ers_result rc, *res = userdata;
struct pci_driver *driver = dev->driver;
struct device_node *dn = pci_device_to_OF_node(dev);
@@ -128,12 +153,14 @@
PCI_DN(dn)->eeh_mode &= ~EEH_MODE_IRQ_DISABLED;
enable_irq(dev->irq);
}
- if (!driver->err_handler)
- return;
- if (!driver->err_handler->slot_reset)
+ if (!driver->err_handler ||
+ !driver->err_handler->slot_reset)
return;
- driver->err_handler->slot_reset(dev);
+ rc = driver->err_handler->slot_reset(dev);
+ if (*res == PCI_ERS_RESULT_NONE) *res = rc;
+ if (*res == PCI_ERS_RESULT_DISCONNECT &&
+ rc == PCI_ERS_RESULT_NEED_RESET) *res = rc;
}
/**
@@ -362,22 +389,42 @@
goto hard_fail;
}
+ /* If all devices reported they can proceed, then re-enable MMIO */
+ if (result == PCI_ERS_RESULT_CAN_RECOVER) {
+ rc = rtas_pci_enable(frozen_pdn, EEH_THAW_MMIO);
+
+ if (rc) {
+ result = PCI_ERS_RESULT_NEED_RESET;
+ } else {
+ result = PCI_ERS_RESULT_NONE;
+ pci_walk_bus(frozen_bus, eeh_report_mmio_enabled, &result);
+ }
+ }
+
+ /* If all devices reported they can proceed, then re-enable DMA */
+ if (result == PCI_ERS_RESULT_CAN_RECOVER) {
+ rc = rtas_pci_enable(frozen_pdn, EEH_THAW_DMA);
+
+ if (rc)
+ result = PCI_ERS_RESULT_NEED_RESET;
+ }
+
+ /* If any device has a hard failure, then shut off everything. */
+ if (result == PCI_ERS_RESULT_DISCONNECT)
+ goto hard_fail;
+
/* If any device called out for a reset, then reset the slot */
if (result == PCI_ERS_RESULT_NEED_RESET) {
rc = eeh_reset_device(frozen_pdn, NULL);
if (rc)
goto hard_fail;
- pci_walk_bus(frozen_bus, eeh_report_reset, NULL);
+ result = PCI_ERS_RESULT_NONE;
+ pci_walk_bus(frozen_bus, eeh_report_reset, &result);
}
- /* If all devices reported they can proceed, the re-enable PIO */
- if (result == PCI_ERS_RESULT_CAN_RECOVER) {
- /* XXX Not supported; we brute-force reset the device */
- rc = eeh_reset_device(frozen_pdn, NULL);
- if (rc)
- goto hard_fail;
- pci_walk_bus(frozen_bus, eeh_report_reset, NULL);
- }
+ /* All devices should claim they have recovered by now. */
+ if (result != PCI_ERS_RESULT_RECOVERED)
+ goto hard_fail;
/* Tell all device drivers that they can resume operations */
pci_walk_bus(frozen_bus, eeh_report_resume, NULL);