xhci: Store information about roothubs and TTs.

For upcoming patches, we need to keep information about the bandwidth
domains under the xHCI host.  Each root port is a separate primary
bandwidth domain, and each high speed hub's TT (and potentially each port
on a multi-TT hub) is a secondary bandwidth domain.

If the table were in text form, it would look a bit like this:

EP Interval	Sum of Number	Largest Max	Max Packet
		of Packets	Packet Size	Overhead
	0	   N		   mps		  overhead
...
	15	   N		   mps		  overhead

Overhead is the maximum packet overhead (for bit stuffing, CRC, protocol
overhead, etc) for all the endpoints in this interval.  Devices with
different speeds have different max packet overhead.  For example, if
there is a low speed and a full speed endpoint that both have an interval
of 3, we would use the higher overhead (the low speed overhead).  Interval
0 is a bit special, since we really just want to know the sum of the max
ESIT payloads instead of the largest max packet size.  That's stored in
the interval0_esit_payload variable.  For root ports, we also need to keep
track of the number of active TTs.

For each root port, and each TT under a root port, store some information
about the bandwidth consumption.  Dynamically allocate an array of root
port bandwidth information for the number of root ports on the xHCI host.
Each root port stores a list of TTs under the root port.  A single TT hub
only has one entry in the list, but a multi-TT hub will have an entry per
port.

When the USB core says that a USB device is a hub, create one or more
entries in the root port TT list for the hub.  When a device is deleted,
and it is a hub, search through the root port TT list and delete all
TT entries for the hub.  Keep track of which TT entry is associated with a
device under a TT.

LS/FS devices attached directly to the root port will have usb_device->tt
set to the roothub.  Ignore that, and treat it like a primary bandwidth
domain, since there isn't really a high speed bus between the roothub and
the host.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 50 insertions, 0 deletions

diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index ec4817003a56..eee47c8a6ee8 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -774,6 +774,26 @@ struct xhci_virt_ep {
         bool                    skip;
 };
 
+enum xhci_overhead_type {
+        LS_OVERHEAD_TYPE = 0,
+        FS_OVERHEAD_TYPE,
+        HS_OVERHEAD_TYPE,
+};
+
+struct xhci_interval_bw {
+        unsigned int            num_packets;
+        /* How many endpoints of each speed are present. */
+        unsigned int            overhead[3];
+};
+
+#define XHCI_MAX_INTERVAL       16
+
+struct xhci_interval_bw_table {
+        unsigned int            interval0_esit_payload;
+        struct xhci_interval_bw interval_bw[XHCI_MAX_INTERVAL];
+};
+
+
 struct xhci_virt_device {
         struct usb_device               *udev;
         /*
@@ -800,6 +820,30 @@ struct xhci_virt_device {
         struct list_head                cmd_list;
         u8                              fake_port;
         u8                              real_port;
+        struct xhci_interval_bw_table   *bw_table;
+        struct xhci_tt_bw_info          *tt_info;
+};
+
+/*
+ * For each roothub, keep track of the bandwidth information for each periodic
+ * interval.
+ *
+ * If a high speed hub is attached to the roothub, each TT associated with that
+ * hub is a separate bandwidth domain.  The interval information for the
+ * endpoints on the devices under that TT will appear in the TT structure.
+ */
+struct xhci_root_port_bw_info {
+        struct list_head                tts;
+        unsigned int                    num_active_tts;
+        struct xhci_interval_bw_table   bw_table;
+};
+
+struct xhci_tt_bw_info {
+        struct list_head                tt_list;
+        int                             slot_id;
+        int                             ttport;
+        struct xhci_interval_bw_table   bw_table;
+        int                             active_eps;
 };
 
 
@@ -1268,6 +1312,8 @@ struct xhci_hcd {
         int slot_id;
         /* Internal mirror of the HW's dcbaa */
         struct xhci_virt_device *devs[MAX_HC_SLOTS];
+        /* For keeping track of bandwidth domains per roothub. */
+        struct xhci_root_port_bw_info   *rh_bw;
 
         /* DMA pools */
         struct dma_pool *device_pool;
@@ -1508,6 +1554,10 @@ irqreturn_t xhci_irq(struct usb_hcd *hcd);
 irqreturn_t xhci_msi_irq(int irq, struct usb_hcd *hcd);
 int xhci_alloc_dev(struct usb_hcd *hcd, struct usb_device *udev);
 void xhci_free_dev(struct usb_hcd *hcd, struct usb_device *udev);
+int xhci_alloc_tt_info(struct xhci_hcd *xhci,
+                struct xhci_virt_device *virt_dev,
+                struct usb_device *hdev,
+                struct usb_tt *tt, gfp_t mem_flags);
 int xhci_alloc_streams(struct usb_hcd *hcd, struct usb_device *udev,
                 struct usb_host_endpoint **eps, unsigned int num_eps,
                 unsigned int num_streams, gfp_t mem_flags);