diff options
| -rw-r--r-- | drivers/usb/host/xhci-hcd.c | 32 | ||||
| -rw-r--r-- | drivers/usb/host/xhci-mem.c | 76 | ||||
| -rw-r--r-- | drivers/usb/host/xhci.h | 4 |
3 files changed, 94 insertions, 18 deletions
diff --git a/drivers/usb/host/xhci-hcd.c b/drivers/usb/host/xhci-hcd.c index 0d5a8564ed1..5e92c72df64 100644 --- a/drivers/usb/host/xhci-hcd.c +++ b/drivers/usb/host/xhci-hcd.c @@ -1262,13 +1262,35 @@ int xhci_check_bandwidth(struct usb_hcd *hcd, struct usb_device *udev) LAST_CTX_TO_EP_NUM(slot_ctx->dev_info)); xhci_zero_in_ctx(xhci, virt_dev); - /* Free any old rings */ + /* Install new rings and free or cache any old rings */ for (i = 1; i < 31; ++i) { - if (virt_dev->eps[i].new_ring) { - xhci_ring_free(xhci, virt_dev->eps[i].ring); - virt_dev->eps[i].ring = virt_dev->eps[i].new_ring; - virt_dev->eps[i].new_ring = NULL; + int rings_cached; + + if (!virt_dev->eps[i].new_ring) + continue; + /* Only cache or free the old ring if it exists. + * It may not if this is the first add of an endpoint. + */ + if (virt_dev->eps[i].ring) { + rings_cached = virt_dev->num_rings_cached; + if (rings_cached < XHCI_MAX_RINGS_CACHED) { + virt_dev->num_rings_cached++; + rings_cached = virt_dev->num_rings_cached; + virt_dev->ring_cache[rings_cached] = + virt_dev->eps[i].ring; + xhci_dbg(xhci, "Cached old ring, " + "%d ring%s cached\n", + rings_cached, + (rings_cached > 1) ? "s" : ""); + } else { + xhci_ring_free(xhci, virt_dev->eps[i].ring); + xhci_dbg(xhci, "Ring cache full (%d rings), " + "freeing ring\n", + virt_dev->num_rings_cached); + } } + virt_dev->eps[i].ring = virt_dev->eps[i].new_ring; + virt_dev->eps[i].new_ring = NULL; } return ret; diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c index 9034721106d..bffcef7a554 100644 --- a/drivers/usb/host/xhci-mem.c +++ b/drivers/usb/host/xhci-mem.c @@ -125,6 +125,23 @@ void xhci_ring_free(struct xhci_hcd *xhci, struct xhci_ring *ring) kfree(ring); } +static void xhci_initialize_ring_info(struct xhci_ring *ring) +{ + /* The ring is empty, so the enqueue pointer == dequeue pointer */ + ring->enqueue = ring->first_seg->trbs; + ring->enq_seg = ring->first_seg; + ring->dequeue = ring->enqueue; + ring->deq_seg = ring->first_seg; + /* The ring is initialized to 0. The producer must write 1 to the cycle + * bit to handover ownership of the TRB, so PCS = 1. The consumer must + * compare CCS to the cycle bit to check ownership, so CCS = 1. + */ + ring->cycle_state = 1; + /* Not necessary for new rings, but needed for re-initialized rings */ + ring->enq_updates = 0; + ring->deq_updates = 0; +} + /** * Create a new ring with zero or more segments. * @@ -173,17 +190,7 @@ static struct xhci_ring *xhci_ring_alloc(struct xhci_hcd *xhci, " segment %p (virtual), 0x%llx (DMA)\n", prev, (unsigned long long)prev->dma); } - /* The ring is empty, so the enqueue pointer == dequeue pointer */ - ring->enqueue = ring->first_seg->trbs; - ring->enq_seg = ring->first_seg; - ring->dequeue = ring->enqueue; - ring->deq_seg = ring->first_seg; - /* The ring is initialized to 0. The producer must write 1 to the cycle - * bit to handover ownership of the TRB, so PCS = 1. The consumer must - * compare CCS to the cycle bit to check ownership, so CCS = 1. - */ - ring->cycle_state = 1; - + xhci_initialize_ring_info(ring); return ring; fail: @@ -191,6 +198,27 @@ fail: return 0; } +/* Zero an endpoint ring (except for link TRBs) and move the enqueue and dequeue + * pointers to the beginning of the ring. + */ +static void xhci_reinit_cached_ring(struct xhci_hcd *xhci, + struct xhci_ring *ring) +{ + struct xhci_segment *seg = ring->first_seg; + do { + memset(seg->trbs, 0, + sizeof(union xhci_trb)*TRBS_PER_SEGMENT); + /* All endpoint rings have link TRBs */ + xhci_link_segments(xhci, seg, seg->next, 1); + seg = seg->next; + } while (seg != ring->first_seg); + xhci_initialize_ring_info(ring); + /* td list should be empty since all URBs have been cancelled, + * but just in case... + */ + INIT_LIST_HEAD(&ring->td_list); +} + #define CTX_SIZE(_hcc) (HCC_64BYTE_CONTEXT(_hcc) ? 64 : 32) struct xhci_container_ctx *xhci_alloc_container_ctx(struct xhci_hcd *xhci, @@ -276,6 +304,12 @@ void xhci_free_virt_device(struct xhci_hcd *xhci, int slot_id) if (dev->eps[i].ring) xhci_ring_free(xhci, dev->eps[i].ring); + if (dev->ring_cache) { + for (i = 0; i < dev->num_rings_cached; i++) + xhci_ring_free(xhci, dev->ring_cache[i]); + kfree(dev->ring_cache); + } + if (dev->in_ctx) xhci_free_container_ctx(xhci, dev->in_ctx); if (dev->out_ctx) @@ -329,6 +363,14 @@ int xhci_alloc_virt_device(struct xhci_hcd *xhci, int slot_id, if (!dev->eps[0].ring) goto fail; + /* Allocate pointers to the ring cache */ + dev->ring_cache = kzalloc( + sizeof(struct xhci_ring *)*XHCI_MAX_RINGS_CACHED, + flags); + if (!dev->ring_cache) + goto fail; + dev->num_rings_cached = 0; + init_completion(&dev->cmd_completion); INIT_LIST_HEAD(&dev->cmd_list); @@ -555,8 +597,16 @@ int xhci_endpoint_init(struct xhci_hcd *xhci, /* Set up the endpoint ring */ virt_dev->eps[ep_index].new_ring = xhci_ring_alloc(xhci, 1, true, mem_flags); - if (!virt_dev->eps[ep_index].new_ring) - return -ENOMEM; + if (!virt_dev->eps[ep_index].new_ring) { + /* Attempt to use the ring cache */ + if (virt_dev->num_rings_cached == 0) + return -ENOMEM; + virt_dev->eps[ep_index].new_ring = + virt_dev->ring_cache[virt_dev->num_rings_cached]; + virt_dev->ring_cache[virt_dev->num_rings_cached] = NULL; + virt_dev->num_rings_cached--; + xhci_reinit_cached_ring(xhci, virt_dev->eps[ep_index].new_ring); + } ep_ring = virt_dev->eps[ep_index].new_ring; ep_ctx->deq = ep_ring->first_seg->dma | ep_ring->cycle_state; diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h index bb8e6656cca..877813505ef 100644 --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -677,6 +677,10 @@ struct xhci_virt_device { struct xhci_container_ctx *out_ctx; /* Used for addressing devices and configuration changes */ struct xhci_container_ctx *in_ctx; + /* Rings saved to ensure old alt settings can be re-instated */ + struct xhci_ring **ring_cache; + int num_rings_cached; +#define XHCI_MAX_RINGS_CACHED 31 struct xhci_virt_ep eps[31]; struct completion cmd_completion; /* Status of the last command issued for this device */ |