Merge branch 'perf/core' into perf/uprobes

Merge in latest upstream (and the latest perf development tree),
to prepare for tooling changes, and also to pick up v3.4 MM
changes that the uprobes code needs to take care of.

Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 109 insertions, 24 deletions

diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index bcdbb164362..a960faec102 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -241,34 +241,79 @@ static int pcie_write_cmd(struct controller *ctrl, u16 cmd, u16 mask)
 	return retval;
 }
 
-static inline int check_link_active(struct controller *ctrl)
+static bool check_link_active(struct controller *ctrl)
 {
-	u16 link_status;
+	bool ret = false;
+	u16 lnk_status;
 
-	if (pciehp_readw(ctrl, PCI_EXP_LNKSTA, &link_status))
-		return 0;
-	return !!(link_status & PCI_EXP_LNKSTA_DLLLA);
+	if (pciehp_readw(ctrl, PCI_EXP_LNKSTA, &lnk_status))
+		return ret;
+
+	ret = !!(lnk_status & PCI_EXP_LNKSTA_DLLLA);
+
+	if (ret)
+		ctrl_dbg(ctrl, "%s: lnk_status = %x\n", __func__, lnk_status);
+
+	return ret;
 }
 
-static void pcie_wait_link_active(struct controller *ctrl)
+static void __pcie_wait_link_active(struct controller *ctrl, bool active)
 {
 	int timeout = 1000;
 
-	if (check_link_active(ctrl))
+	if (check_link_active(ctrl) == active)
 		return;
 	while (timeout > 0) {
 		msleep(10);
 		timeout -= 10;
-		if (check_link_active(ctrl))
+		if (check_link_active(ctrl) == active)
 			return;
 	}
-	ctrl_dbg(ctrl, "Data Link Layer Link Active not set in 1000 msec\n");
+	ctrl_dbg(ctrl, "Data Link Layer Link Active not %s in 1000 msec\n",
+			active ? "set" : "cleared");
+}
+
+static void pcie_wait_link_active(struct controller *ctrl)
+{
+	__pcie_wait_link_active(ctrl, true);
+}
+
+static void pcie_wait_link_not_active(struct controller *ctrl)
+{
+	__pcie_wait_link_active(ctrl, false);
+}
+
+static bool pci_bus_check_dev(struct pci_bus *bus, int devfn)
+{
+	u32 l;
+	int count = 0;
+	int delay = 1000, step = 20;
+	bool found = false;
+
+	do {
+		found = pci_bus_read_dev_vendor_id(bus, devfn, &l, 0);
+		count++;
+
+		if (found)
+			break;
+
+		msleep(step);
+		delay -= step;
+	} while (delay > 0);
+
+	if (count > 1 && pciehp_debug)
+		printk(KERN_DEBUG "pci %04x:%02x:%02x.%d id reading try %d times with interval %d ms to get %08x\n",
+			pci_domain_nr(bus), bus->number, PCI_SLOT(devfn),
+			PCI_FUNC(devfn), count, step, l);
+
+	return found;
 }
 
 int pciehp_check_link_status(struct controller *ctrl)
 {
 	u16 lnk_status;
 	int retval = 0;
+	bool found = false;
 
         /*
          * Data Link Layer Link Active Reporting must be capable for
@@ -280,13 +325,10 @@ int pciehp_check_link_status(struct controller *ctrl)
         else
                 msleep(1000);
 
-	/*
-	 * Need to wait for 1000 ms after Data Link Layer Link Active
-	 * (DLLLA) bit reads 1b before sending configuration request.
-	 * We need it before checking Link Training (LT) bit becuase
-	 * LT is still set even after DLLLA bit is set on some platform.
-	 */
-	msleep(1000);
+	/* wait 100ms before read pci conf, and try in 1s */
+	msleep(100);
+	found = pci_bus_check_dev(ctrl->pcie->port->subordinate,
+					PCI_DEVFN(0, 0));
 
 	retval = pciehp_readw(ctrl, PCI_EXP_LNKSTA, &lnk_status);
 	if (retval) {
@@ -302,19 +344,50 @@ int pciehp_check_link_status(struct controller *ctrl)
 		return retval;
 	}
 
-	/*
-	 * If the port supports Link speeds greater than 5.0 GT/s, we
-	 * must wait for 100 ms after Link training completes before
-	 * sending configuration request.
-	 */
-	if (ctrl->pcie->port->subordinate->max_bus_speed > PCIE_SPEED_5_0GT)
-		msleep(100);
-
 	pcie_update_link_speed(ctrl->pcie->port->subordinate, lnk_status);
 
+	if (!found && !retval)
+		retval = -1;
+
 	return retval;
 }
 
+static int __pciehp_link_set(struct controller *ctrl, bool enable)
+{
+	u16 lnk_ctrl;
+	int retval = 0;
+
+	retval = pciehp_readw(ctrl, PCI_EXP_LNKCTL, &lnk_ctrl);
+	if (retval) {
+		ctrl_err(ctrl, "Cannot read LNKCTRL register\n");
+		return retval;
+	}
+
+	if (enable)
+		lnk_ctrl &= ~PCI_EXP_LNKCTL_LD;
+	else
+		lnk_ctrl |= PCI_EXP_LNKCTL_LD;
+
+	retval = pciehp_writew(ctrl, PCI_EXP_LNKCTL, lnk_ctrl);
+	if (retval) {
+		ctrl_err(ctrl, "Cannot write LNKCTRL register\n");
+		return retval;
+	}
+	ctrl_dbg(ctrl, "%s: lnk_ctrl = %x\n", __func__, lnk_ctrl);
+
+	return retval;
+}
+
+static int pciehp_link_enable(struct controller *ctrl)
+{
+	return __pciehp_link_set(ctrl, true);
+}
+
+static int pciehp_link_disable(struct controller *ctrl)
+{
+	return __pciehp_link_set(ctrl, false);
+}
+
 int pciehp_get_attention_status(struct slot *slot, u8 *status)
 {
 	struct controller *ctrl = slot->ctrl;
@@ -533,6 +606,10 @@ int pciehp_power_on_slot(struct slot * slot)
 	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_cmd);
 
+	retval = pciehp_link_enable(ctrl);
+	if (retval)
+		ctrl_err(ctrl, "%s: Can not enable the link!\n", __func__);
+
 	return retval;
 }
 
@@ -543,6 +620,14 @@ int pciehp_power_off_slot(struct slot * slot)
 	u16 cmd_mask;
 	int retval;
 
+	/* Disable the link at first */
+	pciehp_link_disable(ctrl);
+	/* wait the link is down */
+	if (ctrl->link_active_reporting)
+		pcie_wait_link_not_active(ctrl);
+	else
+		msleep(1000);
+
 	slot_cmd = POWER_OFF;
 	cmd_mask = PCI_EXP_SLTCTL_PCC;
 	retval = pcie_write_cmd(ctrl, slot_cmd, cmd_mask);