pciehp: fix power fault interrupt storm problem

Commit Message

Kenji Kaneshige Nov. 13, 2009, 6:14 a.m. UTC

None

Patch

Index: 20091110/drivers/pci/hotplug/pciehp_ctrl.c
===================================================================
--- 20091110.orig/drivers/pci/hotplug/pciehp_ctrl.c
+++ 20091110/drivers/pci/hotplug/pciehp_ctrl.c
@@ -142,23 +142,9 @@  u8 pciehp_handle_power_fault(struct slot
 
 	/* power fault */
 	ctrl_dbg(ctrl, "Power fault interrupt received\n");
-
-	if (!pciehp_query_power_fault(p_slot)) {
-		/*
-		 * power fault Cleared
-		 */
-		ctrl_info(ctrl, "Power fault cleared on Slot(%s)\n",
-			  slot_name(p_slot));
-		event_type = INT_POWER_FAULT_CLEAR;
-	} else {
-		/*
-		 *   power fault
-		 */
-		ctrl_info(ctrl, "Power fault on Slot(%s)\n", slot_name(p_slot));
-		event_type = INT_POWER_FAULT;
-		ctrl_info(ctrl, "Power fault bit %x set\n", 0);
-	}
-
+	ctrl_err(ctrl, "Power fault on slot %s\n", slot_name(p_slot));
+	event_type = INT_POWER_FAULT;
+	ctrl_info(ctrl, "Power fault bit %x set\n", 0);
 	queue_interrupt_event(p_slot, event_type);
 
 	return 1;
@@ -224,13 +210,12 @@  static int board_added(struct slot *p_sl
 	retval = pciehp_check_link_status(ctrl);
 	if (retval) {
 		ctrl_err(ctrl, "Failed to check link status\n");
-		set_slot_off(ctrl, p_slot);
-		return retval;
+		goto err_exit;
 	}
 
 	/* Check for a power fault */
-	if (pciehp_query_power_fault(p_slot)) {
-		ctrl_dbg(ctrl, "Power fault detected\n");
+	if (ctrl->power_fault_detected || pciehp_query_power_fault(p_slot)) {
+		ctrl_err(ctrl, "Power fault on slot %s\n", slot_name(p_slot));
 		retval = -EIO;
 		goto err_exit;
 	}
Index: 20091110/drivers/pci/hotplug/pciehp_hpc.c
===================================================================
--- 20091110.orig/drivers/pci/hotplug/pciehp_hpc.c
+++ 20091110/drivers/pci/hotplug/pciehp_hpc.c
@@ -511,15 +511,10 @@  int pciehp_power_on_slot(struct slot * s
 			return retval;
 		}
 	}
+	ctrl->power_fault_detected = 0;
 
 	slot_cmd = POWER_ON;
 	cmd_mask = PCI_EXP_SLTCTL_PCC;
-	if (!pciehp_poll_mode) {
-		/* Enable power fault detection turned off at power off time */
-		slot_cmd |= PCI_EXP_SLTCTL_PFDE;
-		cmd_mask |= PCI_EXP_SLTCTL_PFDE;
-	}
-
 	retval = pcie_write_cmd(ctrl, slot_cmd, cmd_mask);
 	if (retval) {
 		ctrl_err(ctrl, "Write %x command failed!\n", slot_cmd);
@@ -528,7 +523,6 @@  int pciehp_power_on_slot(struct slot * s
 	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_cmd);
 
-	ctrl->power_fault_detected = 0;
 	return retval;
 }
 
@@ -541,12 +535,6 @@  int pciehp_power_off_slot(struct slot * 
 
 	slot_cmd = POWER_OFF;
 	cmd_mask = PCI_EXP_SLTCTL_PCC;
-	if (!pciehp_poll_mode) {
-		/* Disable power fault detection */
-		slot_cmd &= ~PCI_EXP_SLTCTL_PFDE;
-		cmd_mask |= PCI_EXP_SLTCTL_PFDE;
-	}
-
 	retval = pcie_write_cmd(ctrl, slot_cmd, cmd_mask);
 	if (retval) {
 		ctrl_err(ctrl, "Write command failed!\n");
@@ -790,11 +778,19 @@  int pcie_enable_notification(struct cont
 {
 	u16 cmd, mask;
 
+	/*
+	 * TBD: Power fault detected software notification support.
+	 *
+	 * Power fault detected software notification is not enabled
+	 * now, because it caused power fault detected interrupt storm
+	 * on some machines. On those machines, power fault detected
+	 * bit in the slot status register was set again immediately
+	 * when it is cleared in the interrupt service routine, and
+	 * next power fault detected interrupt was notified again.
+	 */
 	cmd = PCI_EXP_SLTCTL_PDCE;
 	if (ATTN_BUTTN(ctrl))
 		cmd |= PCI_EXP_SLTCTL_ABPE;
-	if (POWER_CTRL(ctrl))
-		cmd |= PCI_EXP_SLTCTL_PFDE;
 	if (MRL_SENS(ctrl))
 		cmd |= PCI_EXP_SLTCTL_MRLSCE;
 	if (!pciehp_poll_mode)