[U-Boot] [PATCH v3 13/15] usb: xhci: Implement update_hub_device() operation

[Bin Meng]

There is no way to know whether the attached device is a hub or
not in advance before the device's descriptor is fetched. But
once we know it's a high speed hub, per the xHCI spec, we need
to tell xHC it's a hub device by initializing hub-related fields
in the input slot context.

Signed-off-by: Bin Meng <bmeng.cn at gmail.com>
Reviewed-by: Simon Glass <sjg at chromium.org>

---

Changes in v3: None
Changes in v2:
- fix several nits in the commit message
- add a comment for 666 in TT think time

 drivers/usb/host/xhci.c | 59 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 59 insertions(+)

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 336613f..9b82ee5 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -1170,6 +1170,64 @@ static int xhci_alloc_device(struct udevice *dev, struct usb_device *udev)
 	return _xhci_alloc_device(udev);
 }
 
+static int xhci_update_hub_device(struct udevice *dev, struct usb_device *udev)
+{
+	struct xhci_ctrl *ctrl = dev_get_priv(dev);
+	struct usb_hub_device *hub = dev_get_uclass_priv(udev->dev);
+	struct xhci_virt_device *virt_dev;
+	struct xhci_input_control_ctx *ctrl_ctx;
+	struct xhci_container_ctx *out_ctx;
+	struct xhci_container_ctx *in_ctx;
+	struct xhci_slot_ctx *slot_ctx;
+	int slot_id = udev->slot_id;
+	unsigned think_time;
+
+	debug("%s: dev='%s', udev=%p\n", __func__, dev->name, udev);
+
+	/* Ignore root hubs */
+	if (usb_hub_is_root_hub(udev->dev))
+		return 0;
+
+	virt_dev = ctrl->devs[slot_id];
+	BUG_ON(!virt_dev);
+
+	out_ctx = virt_dev->out_ctx;
+	in_ctx = virt_dev->in_ctx;
+
+	ctrl_ctx = xhci_get_input_control_ctx(in_ctx);
+	/* Initialize the input context control */
+	ctrl_ctx->add_flags |= cpu_to_le32(SLOT_FLAG);
+	ctrl_ctx->drop_flags = 0;
+
+	xhci_inval_cache((uintptr_t)out_ctx->bytes, out_ctx->size);
+
+	/* slot context */
+	xhci_slot_copy(ctrl, in_ctx, out_ctx);
+	slot_ctx = xhci_get_slot_ctx(ctrl, in_ctx);
+
+	/* Update hub related fields */
+	slot_ctx->dev_info |= cpu_to_le32(DEV_HUB);
+	if (hub->tt.multi && udev->speed == USB_SPEED_HIGH)
+		slot_ctx->dev_info |= cpu_to_le32(DEV_MTT);
+	slot_ctx->dev_info2 |= cpu_to_le32(XHCI_MAX_PORTS(udev->maxchild));
+	/*
+	 * Set TT think time - convert from ns to FS bit times.
+	 * Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns
+	 *
+	 * 0 =  8 FS bit times, 1 = 16 FS bit times,
+	 * 2 = 24 FS bit times, 3 = 32 FS bit times.
+	 *
+	 * This field shall be 0 if the device is not a high-spped hub.
+	 */
+	think_time = hub->tt.think_time;
+	if (think_time != 0)
+		think_time = (think_time / 666) - 1;
+	if (udev->speed == USB_SPEED_HIGH)
+		slot_ctx->tt_info |= cpu_to_le32(TT_THINK_TIME(think_time));
+
+	return xhci_configure_endpoints(udev, false);
+}
+
 int xhci_register(struct udevice *dev, struct xhci_hccr *hccr,
 		  struct xhci_hcor *hcor)
 {
@@ -1222,6 +1280,7 @@ struct dm_usb_ops xhci_usb_ops = {
 	.bulk = xhci_submit_bulk_msg,
 	.interrupt = xhci_submit_int_msg,
 	.alloc_device = xhci_alloc_device,
+	.update_hub_device = xhci_update_hub_device,
 };
 
 #endif
-- 
2.9.2