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-rw-r--r--drivers/usb/host/xhci-pci.c2
-rw-r--r--drivers/usb/host/xhci-ring.c7
-rw-r--r--drivers/usb/host/xhci.c232
-rw-r--r--drivers/usb/host/xhci.h14
4 files changed, 244 insertions, 11 deletions
diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index eafd17f..c408e9f 100644
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -121,6 +121,8 @@ static int xhci_pci_setup(struct usb_hcd *hcd)
if (pdev->vendor == PCI_VENDOR_ID_INTEL &&
pdev->device == PCI_DEVICE_ID_INTEL_PANTHERPOINT_XHCI) {
xhci->quirks |= XHCI_SPURIOUS_SUCCESS;
+ xhci->quirks |= XHCI_EP_LIMIT_QUIRK;
+ xhci->limit_active_eps = 64;
}
/* Make sure the HC is halted. */
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 56f6c58..cc1485b 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -1081,8 +1081,13 @@ static void handle_cmd_completion(struct xhci_hcd *xhci,
complete(&xhci->addr_dev);
break;
case TRB_TYPE(TRB_DISABLE_SLOT):
- if (xhci->devs[slot_id])
+ if (xhci->devs[slot_id]) {
+ if (xhci->quirks & XHCI_EP_LIMIT_QUIRK)
+ /* Delete default control endpoint resources */
+ xhci_free_device_endpoint_resources(xhci,
+ xhci->devs[slot_id], true);
xhci_free_virt_device(xhci, slot_id);
+ }
break;
case TRB_TYPE(TRB_CONFIG_EP):
virt_dev = xhci->devs[slot_id];
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 58183d2..d9660eb 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -1582,6 +1582,113 @@ static int xhci_evaluate_context_result(struct xhci_hcd *xhci,
return ret;
}
+static u32 xhci_count_num_new_endpoints(struct xhci_hcd *xhci,
+ struct xhci_container_ctx *in_ctx)
+{
+ struct xhci_input_control_ctx *ctrl_ctx;
+ u32 valid_add_flags;
+ u32 valid_drop_flags;
+
+ ctrl_ctx = xhci_get_input_control_ctx(xhci, in_ctx);
+ /* Ignore the slot flag (bit 0), and the default control endpoint flag
+ * (bit 1). The default control endpoint is added during the Address
+ * Device command and is never removed until the slot is disabled.
+ */
+ valid_add_flags = ctrl_ctx->add_flags >> 2;
+ valid_drop_flags = ctrl_ctx->drop_flags >> 2;
+
+ /* Use hweight32 to count the number of ones in the add flags, or
+ * number of endpoints added. Don't count endpoints that are changed
+ * (both added and dropped).
+ */
+ return hweight32(valid_add_flags) -
+ hweight32(valid_add_flags & valid_drop_flags);
+}
+
+static unsigned int xhci_count_num_dropped_endpoints(struct xhci_hcd *xhci,
+ struct xhci_container_ctx *in_ctx)
+{
+ struct xhci_input_control_ctx *ctrl_ctx;
+ u32 valid_add_flags;
+ u32 valid_drop_flags;
+
+ ctrl_ctx = xhci_get_input_control_ctx(xhci, in_ctx);
+ valid_add_flags = ctrl_ctx->add_flags >> 2;
+ valid_drop_flags = ctrl_ctx->drop_flags >> 2;
+
+ return hweight32(valid_drop_flags) -
+ hweight32(valid_add_flags & valid_drop_flags);
+}
+
+/*
+ * We need to reserve the new number of endpoints before the configure endpoint
+ * command completes. We can't subtract the dropped endpoints from the number
+ * of active endpoints until the command completes because we can oversubscribe
+ * the host in this case:
+ *
+ * - the first configure endpoint command drops more endpoints than it adds
+ * - a second configure endpoint command that adds more endpoints is queued
+ * - the first configure endpoint command fails, so the config is unchanged
+ * - the second command may succeed, even though there isn't enough resources
+ *
+ * Must be called with xhci->lock held.
+ */
+static int xhci_reserve_host_resources(struct xhci_hcd *xhci,
+ struct xhci_container_ctx *in_ctx)
+{
+ u32 added_eps;
+
+ added_eps = xhci_count_num_new_endpoints(xhci, in_ctx);
+ if (xhci->num_active_eps + added_eps > xhci->limit_active_eps) {
+ xhci_dbg(xhci, "Not enough ep ctxs: "
+ "%u active, need to add %u, limit is %u.\n",
+ xhci->num_active_eps, added_eps,
+ xhci->limit_active_eps);
+ return -ENOMEM;
+ }
+ xhci->num_active_eps += added_eps;
+ xhci_dbg(xhci, "Adding %u ep ctxs, %u now active.\n", added_eps,
+ xhci->num_active_eps);
+ return 0;
+}
+
+/*
+ * The configure endpoint was failed by the xHC for some other reason, so we
+ * need to revert the resources that failed configuration would have used.
+ *
+ * Must be called with xhci->lock held.
+ */
+static void xhci_free_host_resources(struct xhci_hcd *xhci,
+ struct xhci_container_ctx *in_ctx)
+{
+ u32 num_failed_eps;
+
+ num_failed_eps = xhci_count_num_new_endpoints(xhci, in_ctx);
+ xhci->num_active_eps -= num_failed_eps;
+ xhci_dbg(xhci, "Removing %u failed ep ctxs, %u now active.\n",
+ num_failed_eps,
+ xhci->num_active_eps);
+}
+
+/*
+ * Now that the command has completed, clean up the active endpoint count by
+ * subtracting out the endpoints that were dropped (but not changed).
+ *
+ * Must be called with xhci->lock held.
+ */
+static void xhci_finish_resource_reservation(struct xhci_hcd *xhci,
+ struct xhci_container_ctx *in_ctx)
+{
+ u32 num_dropped_eps;
+
+ num_dropped_eps = xhci_count_num_dropped_endpoints(xhci, in_ctx);
+ xhci->num_active_eps -= num_dropped_eps;
+ if (num_dropped_eps)
+ xhci_dbg(xhci, "Removing %u dropped ep ctxs, %u now active.\n",
+ num_dropped_eps,
+ xhci->num_active_eps);
+}
+
/* Issue a configure endpoint command or evaluate context command
* and wait for it to finish.
*/
@@ -1602,6 +1709,15 @@ static int xhci_configure_endpoint(struct xhci_hcd *xhci,
virt_dev = xhci->devs[udev->slot_id];
if (command) {
in_ctx = command->in_ctx;
+ if ((xhci->quirks & XHCI_EP_LIMIT_QUIRK) &&
+ xhci_reserve_host_resources(xhci, in_ctx)) {
+ spin_unlock_irqrestore(&xhci->lock, flags);
+ xhci_warn(xhci, "Not enough host resources, "
+ "active endpoint contexts = %u\n",
+ xhci->num_active_eps);
+ return -ENOMEM;
+ }
+
cmd_completion = command->completion;
cmd_status = &command->status;
command->command_trb = xhci->cmd_ring->enqueue;
@@ -1617,6 +1733,14 @@ static int xhci_configure_endpoint(struct xhci_hcd *xhci,
list_add_tail(&command->cmd_list, &virt_dev->cmd_list);
} else {
in_ctx = virt_dev->in_ctx;
+ if ((xhci->quirks & XHCI_EP_LIMIT_QUIRK) &&
+ xhci_reserve_host_resources(xhci, in_ctx)) {
+ spin_unlock_irqrestore(&xhci->lock, flags);
+ xhci_warn(xhci, "Not enough host resources, "
+ "active endpoint contexts = %u\n",
+ xhci->num_active_eps);
+ return -ENOMEM;
+ }
cmd_completion = &virt_dev->cmd_completion;
cmd_status = &virt_dev->cmd_status;
}
@@ -1631,6 +1755,8 @@ static int xhci_configure_endpoint(struct xhci_hcd *xhci,
if (ret < 0) {
if (command)
list_del(&command->cmd_list);
+ if ((xhci->quirks & XHCI_EP_LIMIT_QUIRK))
+ xhci_free_host_resources(xhci, in_ctx);
spin_unlock_irqrestore(&xhci->lock, flags);
xhci_dbg(xhci, "FIXME allocate a new ring segment\n");
return -ENOMEM;
@@ -1653,8 +1779,22 @@ static int xhci_configure_endpoint(struct xhci_hcd *xhci,
}
if (!ctx_change)
- return xhci_configure_endpoint_result(xhci, udev, cmd_status);
- return xhci_evaluate_context_result(xhci, udev, cmd_status);
+ ret = xhci_configure_endpoint_result(xhci, udev, cmd_status);
+ else
+ ret = xhci_evaluate_context_result(xhci, udev, cmd_status);
+
+ if ((xhci->quirks & XHCI_EP_LIMIT_QUIRK)) {
+ spin_lock_irqsave(&xhci->lock, flags);
+ /* If the command failed, remove the reserved resources.
+ * Otherwise, clean up the estimate to include dropped eps.
+ */
+ if (ret)
+ xhci_free_host_resources(xhci, in_ctx);
+ else
+ xhci_finish_resource_reservation(xhci, in_ctx);
+ spin_unlock_irqrestore(&xhci->lock, flags);
+ }
+ return ret;
}
/* Called after one or more calls to xhci_add_endpoint() or
@@ -2272,6 +2412,34 @@ int xhci_free_streams(struct usb_hcd *hcd, struct usb_device *udev,
}
/*
+ * Deletes endpoint resources for endpoints that were active before a Reset
+ * Device command, or a Disable Slot command. The Reset Device command leaves
+ * the control endpoint intact, whereas the Disable Slot command deletes it.
+ *
+ * Must be called with xhci->lock held.
+ */
+void xhci_free_device_endpoint_resources(struct xhci_hcd *xhci,
+ struct xhci_virt_device *virt_dev, bool drop_control_ep)
+{
+ int i;
+ unsigned int num_dropped_eps = 0;
+ unsigned int drop_flags = 0;
+
+ for (i = (drop_control_ep ? 0 : 1); i < 31; i++) {
+ if (virt_dev->eps[i].ring) {
+ drop_flags |= 1 << i;
+ num_dropped_eps++;
+ }
+ }
+ xhci->num_active_eps -= num_dropped_eps;
+ if (num_dropped_eps)
+ xhci_dbg(xhci, "Dropped %u ep ctxs, flags = 0x%x, "
+ "%u now active.\n",
+ num_dropped_eps, drop_flags,
+ xhci->num_active_eps);
+}
+
+/*
* This submits a Reset Device Command, which will set the device state to 0,
* set the device address to 0, and disable all the endpoints except the default
* control endpoint. The USB core should come back and call
@@ -2412,6 +2580,14 @@ int xhci_discover_or_reset_device(struct usb_hcd *hcd, struct usb_device *udev)
goto command_cleanup;
}
+ /* Free up host controller endpoint resources */
+ if ((xhci->quirks & XHCI_EP_LIMIT_QUIRK)) {
+ spin_lock_irqsave(&xhci->lock, flags);
+ /* Don't delete the default control endpoint resources */
+ xhci_free_device_endpoint_resources(xhci, virt_dev, false);
+ spin_unlock_irqrestore(&xhci->lock, flags);
+ }
+
/* Everything but endpoint 0 is disabled, so free or cache the rings. */
last_freed_endpoint = 1;
for (i = 1; i < 31; ++i) {
@@ -2485,6 +2661,27 @@ void xhci_free_dev(struct usb_hcd *hcd, struct usb_device *udev)
}
/*
+ * Checks if we have enough host controller resources for the default control
+ * endpoint.
+ *
+ * Must be called with xhci->lock held.
+ */
+static int xhci_reserve_host_control_ep_resources(struct xhci_hcd *xhci)
+{
+ if (xhci->num_active_eps + 1 > xhci->limit_active_eps) {
+ xhci_dbg(xhci, "Not enough ep ctxs: "
+ "%u active, need to add 1, limit is %u.\n",
+ xhci->num_active_eps, xhci->limit_active_eps);
+ return -ENOMEM;
+ }
+ xhci->num_active_eps += 1;
+ xhci_dbg(xhci, "Adding 1 ep ctx, %u now active.\n",
+ xhci->num_active_eps);
+ return 0;
+}
+
+
+/*
* Returns 0 if the xHC ran out of device slots, the Enable Slot command
* timed out, or allocating memory failed. Returns 1 on success.
*/
@@ -2519,24 +2716,39 @@ int xhci_alloc_dev(struct usb_hcd *hcd, struct usb_device *udev)
xhci_err(xhci, "Error while assigning device slot ID\n");
return 0;
}
- /* xhci_alloc_virt_device() does not touch rings; no need to lock.
- * Use GFP_NOIO, since this function can be called from
+
+ if ((xhci->quirks & XHCI_EP_LIMIT_QUIRK)) {
+ spin_lock_irqsave(&xhci->lock, flags);
+ ret = xhci_reserve_host_control_ep_resources(xhci);
+ if (ret) {
+ spin_unlock_irqrestore(&xhci->lock, flags);
+ xhci_warn(xhci, "Not enough host resources, "
+ "active endpoint contexts = %u\n",
+ xhci->num_active_eps);
+ goto disable_slot;
+ }
+ spin_unlock_irqrestore(&xhci->lock, flags);
+ }
+ /* Use GFP_NOIO, since this function can be called from
* xhci_discover_or_reset_device(), which may be called as part of
* mass storage driver error handling.
*/
if (!xhci_alloc_virt_device(xhci, xhci->slot_id, udev, GFP_NOIO)) {
- /* Disable slot, if we can do it without mem alloc */
xhci_warn(xhci, "Could not allocate xHCI USB device data structures\n");
- spin_lock_irqsave(&xhci->lock, flags);
- if (!xhci_queue_slot_control(xhci, TRB_DISABLE_SLOT, udev->slot_id))
- xhci_ring_cmd_db(xhci);
- spin_unlock_irqrestore(&xhci->lock, flags);
- return 0;
+ goto disable_slot;
}
udev->slot_id = xhci->slot_id;
/* Is this a LS or FS device under a HS hub? */
/* Hub or peripherial? */
return 1;
+
+disable_slot:
+ /* Disable slot, if we can do it without mem alloc */
+ spin_lock_irqsave(&xhci->lock, flags);
+ if (!xhci_queue_slot_control(xhci, TRB_DISABLE_SLOT, udev->slot_id))
+ xhci_ring_cmd_db(xhci);
+ spin_unlock_irqrestore(&xhci->lock, flags);
+ return 0;
}
/*
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 5cfeb86..ac0196e 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1292,6 +1292,18 @@ struct xhci_hcd {
#define XHCI_NEC_HOST (1 << 2)
#define XHCI_AMD_PLL_FIX (1 << 3)
#define XHCI_SPURIOUS_SUCCESS (1 << 4)
+/*
+ * Certain Intel host controllers have a limit to the number of endpoint
+ * contexts they can handle. Ideally, they would signal that they can't handle
+ * anymore endpoint contexts by returning a Resource Error for the Configure
+ * Endpoint command, but they don't. Instead they expect software to keep track
+ * of the number of active endpoints for them, across configure endpoint
+ * commands, reset device commands, disable slot commands, and address device
+ * commands.
+ */
+#define XHCI_EP_LIMIT_QUIRK (1 << 5)
+ unsigned int num_active_eps;
+ unsigned int limit_active_eps;
/* There are two roothubs to keep track of bus suspend info for */
struct xhci_bus_state bus_state[2];
/* Is each xHCI roothub port a USB 3.0, USB 2.0, or USB 1.1 port? */
@@ -1435,6 +1447,8 @@ void xhci_setup_streams_ep_input_ctx(struct xhci_hcd *xhci,
void xhci_setup_no_streams_ep_input_ctx(struct xhci_hcd *xhci,
struct xhci_ep_ctx *ep_ctx,
struct xhci_virt_ep *ep);
+void xhci_free_device_endpoint_resources(struct xhci_hcd *xhci,
+ struct xhci_virt_device *virt_dev, bool drop_control_ep);
struct xhci_ring *xhci_dma_to_transfer_ring(
struct xhci_virt_ep *ep,
u64 address);