summary refs log tree commit diff
path: root/drivers/pci
diff options
context:
space:
mode:
authorKenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>2011-07-11 10:15:45 +0900
committerJesse Barnes <jbarnes@virtuousgeek.org>2011-07-22 09:06:41 -0700
commit0cab0841dc1400f633a7e1ac1e448518692f927a (patch)
tree2b4ba002d6d4ee69ad351a2bcf7f9c484f696d2f /drivers/pci
parent9b373ed18f745bddf4288f1ec4a51fe822b8610a (diff)
downloadlinux-0cab0841dc1400f633a7e1ac1e448518692f927a.tar.gz
PCI: pciehp: change wait time for valid configuration access
Naoki Yanagimoto reported that configuration read on some hot-added
PCIe device returns invalid value. This patch fixes this problem.

According to the PCIe spec, software must wait for at least 1 second
to judge if the hot-added device is broken after Data Link Layer State
Changed Event. This patch changes pciehp driver to wait for 1 second
after the Data Link Layer State Changed Event is detected before
initiating a configuration access instead of 100 ms.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Tested-by: Naoki Yanagimoto <yanagimoto@np.css.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Diffstat (limited to 'drivers/pci')
-rw-r--r--drivers/pci/hotplug/pciehp_ctrl.c3
-rw-r--r--drivers/pci/hotplug/pciehp_hpc.c11
2 files changed, 5 insertions, 9 deletions
diff --git a/drivers/pci/hotplug/pciehp_ctrl.c b/drivers/pci/hotplug/pciehp_ctrl.c
index 085dbb5fc168..1e9c9aacc3a6 100644
--- a/drivers/pci/hotplug/pciehp_ctrl.c
+++ b/drivers/pci/hotplug/pciehp_ctrl.c
@@ -213,6 +213,9 @@ static int board_added(struct slot *p_slot)
 		goto err_exit;
 	}
 
+	/* Wait for 1 second after checking link training status */
+	msleep(1000);
+
 	/* Check for a power fault */
 	if (ctrl->power_fault_detected || pciehp_query_power_fault(p_slot)) {
 		ctrl_err(ctrl, "Power fault on slot %s\n", slot_name(p_slot));
diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index 50a23da5d24d..96dc4734e4af 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -275,16 +275,9 @@ int pciehp_check_link_status(struct controller *ctrl)
          * hot-plug capable downstream port. But old controller might
          * not implement it. In this case, we wait for 1000 ms.
          */
-        if (ctrl->link_active_reporting){
-                /* Wait for Data Link Layer Link Active bit to be set */
+        if (ctrl->link_active_reporting)
                 pcie_wait_link_active(ctrl);
-                /*
-                 * We must wait for 100 ms after the Data Link Layer
-                 * Link Active bit reads 1b before initiating a
-                 * configuration access to the hot added device.
-                 */
-                msleep(100);
-        } else
+        else
                 msleep(1000);
 
 	retval = pciehp_readw(ctrl, PCI_EXP_LNKSTA, &lnk_status);