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WSL2-Linux-Kernel/drivers/usb/host/xhci-ring.c

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/*
* xHCI host controller driver
*
* Copyright (C) 2008 Intel Corp.
*
* Author: Sarah Sharp
* Some code borrowed from the Linux EHCI driver.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/*
* Ring initialization rules:
* 1. Each segment is initialized to zero, except for link TRBs.
* 2. Ring cycle state = 0. This represents Producer Cycle State (PCS) or
* Consumer Cycle State (CCS), depending on ring function.
* 3. Enqueue pointer = dequeue pointer = address of first TRB in the segment.
*
* Ring behavior rules:
* 1. A ring is empty if enqueue == dequeue. This means there will always be at
* least one free TRB in the ring. This is useful if you want to turn that
* into a link TRB and expand the ring.
* 2. When incrementing an enqueue or dequeue pointer, if the next TRB is a
* link TRB, then load the pointer with the address in the link TRB. If the
* link TRB had its toggle bit set, you may need to update the ring cycle
* state (see cycle bit rules). You may have to do this multiple times
* until you reach a non-link TRB.
* 3. A ring is full if enqueue++ (for the definition of increment above)
* equals the dequeue pointer.
*
* Cycle bit rules:
* 1. When a consumer increments a dequeue pointer and encounters a toggle bit
* in a link TRB, it must toggle the ring cycle state.
* 2. When a producer increments an enqueue pointer and encounters a toggle bit
* in a link TRB, it must toggle the ring cycle state.
*
* Producer rules:
* 1. Check if ring is full before you enqueue.
* 2. Write the ring cycle state to the cycle bit in the TRB you're enqueuing.
* Update enqueue pointer between each write (which may update the ring
* cycle state).
* 3. Notify consumer. If SW is producer, it rings the doorbell for command
* and endpoint rings. If HC is the producer for the event ring,
* and it generates an interrupt according to interrupt modulation rules.
*
* Consumer rules:
* 1. Check if TRB belongs to you. If the cycle bit == your ring cycle state,
* the TRB is owned by the consumer.
* 2. Update dequeue pointer (which may update the ring cycle state) and
* continue processing TRBs until you reach a TRB which is not owned by you.
* 3. Notify the producer. SW is the consumer for the event ring, and it
* updates event ring dequeue pointer. HC is the consumer for the command and
* endpoint rings; it generates events on the event ring for these.
*/
#include <linux/scatterlist.h>
#include "xhci.h"
/*
* Returns zero if the TRB isn't in this segment, otherwise it returns the DMA
* address of the TRB.
*/
dma_addr_t xhci_trb_virt_to_dma(struct xhci_segment *seg,
union xhci_trb *trb)
{
unsigned long segment_offset;
if (!seg || !trb || trb < seg->trbs)
return 0;
/* offset in TRBs */
segment_offset = trb - seg->trbs;
if (segment_offset > TRBS_PER_SEGMENT)
return 0;
return seg->dma + (segment_offset * sizeof(*trb));
}
/* Does this link TRB point to the first segment in a ring,
* or was the previous TRB the last TRB on the last segment in the ERST?
*/
static inline bool last_trb_on_last_seg(struct xhci_hcd *xhci, struct xhci_ring *ring,
struct xhci_segment *seg, union xhci_trb *trb)
{
if (ring == xhci->event_ring)
return (trb == &seg->trbs[TRBS_PER_SEGMENT]) &&
(seg->next == xhci->event_ring->first_seg);
else
return trb->link.control & LINK_TOGGLE;
}
/* Is this TRB a link TRB or was the last TRB the last TRB in this event ring
* segment? I.e. would the updated event TRB pointer step off the end of the
* event seg?
*/
static inline int last_trb(struct xhci_hcd *xhci, struct xhci_ring *ring,
struct xhci_segment *seg, union xhci_trb *trb)
{
if (ring == xhci->event_ring)
return trb == &seg->trbs[TRBS_PER_SEGMENT];
else
return (trb->link.control & TRB_TYPE_BITMASK) == TRB_TYPE(TRB_LINK);
}
/* Updates trb to point to the next TRB in the ring, and updates seg if the next
* TRB is in a new segment. This does not skip over link TRBs, and it does not
* effect the ring dequeue or enqueue pointers.
*/
static void next_trb(struct xhci_hcd *xhci,
struct xhci_ring *ring,
struct xhci_segment **seg,
union xhci_trb **trb)
{
if (last_trb(xhci, ring, *seg, *trb)) {
*seg = (*seg)->next;
*trb = ((*seg)->trbs);
} else {
*trb = (*trb)++;
}
}
/*
* See Cycle bit rules. SW is the consumer for the event ring only.
* Don't make a ring full of link TRBs. That would be dumb and this would loop.
*/
static void inc_deq(struct xhci_hcd *xhci, struct xhci_ring *ring, bool consumer)
{
union xhci_trb *next = ++(ring->dequeue);
unsigned long long addr;
ring->deq_updates++;
/* Update the dequeue pointer further if that was a link TRB or we're at
* the end of an event ring segment (which doesn't have link TRBS)
*/
while (last_trb(xhci, ring, ring->deq_seg, next)) {
if (consumer && last_trb_on_last_seg(xhci, ring, ring->deq_seg, next)) {
ring->cycle_state = (ring->cycle_state ? 0 : 1);
if (!in_interrupt())
xhci_dbg(xhci, "Toggle cycle state for ring %p = %i\n",
ring,
(unsigned int) ring->cycle_state);
}
ring->deq_seg = ring->deq_seg->next;
ring->dequeue = ring->deq_seg->trbs;
next = ring->dequeue;
}
addr = (unsigned long long) xhci_trb_virt_to_dma(ring->deq_seg, ring->dequeue);
if (ring == xhci->event_ring)
xhci_dbg(xhci, "Event ring deq = 0x%llx (DMA)\n", addr);
else if (ring == xhci->cmd_ring)
xhci_dbg(xhci, "Command ring deq = 0x%llx (DMA)\n", addr);
else
xhci_dbg(xhci, "Ring deq = 0x%llx (DMA)\n", addr);
}
/*
* See Cycle bit rules. SW is the consumer for the event ring only.
* Don't make a ring full of link TRBs. That would be dumb and this would loop.
*
* If we've just enqueued a TRB that is in the middle of a TD (meaning the
* chain bit is set), then set the chain bit in all the following link TRBs.
* If we've enqueued the last TRB in a TD, make sure the following link TRBs
* have their chain bit cleared (so that each Link TRB is a separate TD).
*
* Section 6.4.4.1 of the 0.95 spec says link TRBs cannot have the chain bit
* set, but other sections talk about dealing with the chain bit set.
* Assume section 6.4.4.1 is wrong, and the chain bit can be set in a Link TRB.
*/
static void inc_enq(struct xhci_hcd *xhci, struct xhci_ring *ring, bool consumer)
{
u32 chain;
union xhci_trb *next;
unsigned long long addr;
chain = ring->enqueue->generic.field[3] & TRB_CHAIN;
next = ++(ring->enqueue);
ring->enq_updates++;
/* Update the dequeue pointer further if that was a link TRB or we're at
* the end of an event ring segment (which doesn't have link TRBS)
*/
while (last_trb(xhci, ring, ring->enq_seg, next)) {
if (!consumer) {
if (ring != xhci->event_ring) {
next->link.control &= ~TRB_CHAIN;
next->link.control |= chain;
/* Give this link TRB to the hardware */
wmb();
if (next->link.control & TRB_CYCLE)
next->link.control &= (u32) ~TRB_CYCLE;
else
next->link.control |= (u32) TRB_CYCLE;
}
/* Toggle the cycle bit after the last ring segment. */
if (last_trb_on_last_seg(xhci, ring, ring->enq_seg, next)) {
ring->cycle_state = (ring->cycle_state ? 0 : 1);
if (!in_interrupt())
xhci_dbg(xhci, "Toggle cycle state for ring %p = %i\n",
ring,
(unsigned int) ring->cycle_state);
}
}
ring->enq_seg = ring->enq_seg->next;
ring->enqueue = ring->enq_seg->trbs;
next = ring->enqueue;
}
addr = (unsigned long long) xhci_trb_virt_to_dma(ring->enq_seg, ring->enqueue);
if (ring == xhci->event_ring)
xhci_dbg(xhci, "Event ring enq = 0x%llx (DMA)\n", addr);
else if (ring == xhci->cmd_ring)
xhci_dbg(xhci, "Command ring enq = 0x%llx (DMA)\n", addr);
else
xhci_dbg(xhci, "Ring enq = 0x%llx (DMA)\n", addr);
}
/*
* Check to see if there's room to enqueue num_trbs on the ring. See rules
* above.
* FIXME: this would be simpler and faster if we just kept track of the number
* of free TRBs in a ring.
*/
static int room_on_ring(struct xhci_hcd *xhci, struct xhci_ring *ring,
unsigned int num_trbs)
{
int i;
union xhci_trb *enq = ring->enqueue;
struct xhci_segment *enq_seg = ring->enq_seg;
/* Check if ring is empty */
if (enq == ring->dequeue)
return 1;
/* Make sure there's an extra empty TRB available */
for (i = 0; i <= num_trbs; ++i) {
if (enq == ring->dequeue)
return 0;
enq++;
while (last_trb(xhci, ring, enq_seg, enq)) {
enq_seg = enq_seg->next;
enq = enq_seg->trbs;
}
}
return 1;
}
void xhci_set_hc_event_deq(struct xhci_hcd *xhci)
{
u64 temp;
dma_addr_t deq;
deq = xhci_trb_virt_to_dma(xhci->event_ring->deq_seg,
xhci->event_ring->dequeue);
if (deq == 0 && !in_interrupt())
xhci_warn(xhci, "WARN something wrong with SW event ring "
"dequeue ptr.\n");
/* Update HC event ring dequeue pointer */
temp = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue);
temp &= ERST_PTR_MASK;
/* Don't clear the EHB bit (which is RW1C) because
* there might be more events to service.
*/
temp &= ~ERST_EHB;
xhci_dbg(xhci, "// Write event ring dequeue pointer, preserving EHB bit\n");
xhci_write_64(xhci, ((u64) deq & (u64) ~ERST_PTR_MASK) | temp,
&xhci->ir_set->erst_dequeue);
}
/* Ring the host controller doorbell after placing a command on the ring */
void xhci_ring_cmd_db(struct xhci_hcd *xhci)
{
u32 temp;
xhci_dbg(xhci, "// Ding dong!\n");
temp = xhci_readl(xhci, &xhci->dba->doorbell[0]) & DB_MASK;
xhci_writel(xhci, temp | DB_TARGET_HOST, &xhci->dba->doorbell[0]);
/* Flush PCI posted writes */
xhci_readl(xhci, &xhci->dba->doorbell[0]);
}
static void ring_ep_doorbell(struct xhci_hcd *xhci,
unsigned int slot_id,
unsigned int ep_index)
{
struct xhci_ring *ep_ring;
u32 field;
__u32 __iomem *db_addr = &xhci->dba->doorbell[slot_id];
ep_ring = xhci->devs[slot_id]->ep_rings[ep_index];
/* Don't ring the doorbell for this endpoint if there are pending
* cancellations because the we don't want to interrupt processing.
*/
if (!ep_ring->cancels_pending && !(ep_ring->state & SET_DEQ_PENDING)
&& !(ep_ring->state & EP_HALTED)) {
field = xhci_readl(xhci, db_addr) & DB_MASK;
xhci_writel(xhci, field | EPI_TO_DB(ep_index), db_addr);
/* Flush PCI posted writes - FIXME Matthew Wilcox says this
* isn't time-critical and we shouldn't make the CPU wait for
* the flush.
*/
xhci_readl(xhci, db_addr);
}
}
/*
* Find the segment that trb is in. Start searching in start_seg.
* If we must move past a segment that has a link TRB with a toggle cycle state
* bit set, then we will toggle the value pointed at by cycle_state.
*/
static struct xhci_segment *find_trb_seg(
struct xhci_segment *start_seg,
union xhci_trb *trb, int *cycle_state)
{
struct xhci_segment *cur_seg = start_seg;
struct xhci_generic_trb *generic_trb;
while (cur_seg->trbs > trb ||
&cur_seg->trbs[TRBS_PER_SEGMENT - 1] < trb) {
generic_trb = &cur_seg->trbs[TRBS_PER_SEGMENT - 1].generic;
if (TRB_TYPE(generic_trb->field[3]) == TRB_LINK &&
(generic_trb->field[3] & LINK_TOGGLE))
*cycle_state = ~(*cycle_state) & 0x1;
cur_seg = cur_seg->next;
if (cur_seg == start_seg)
/* Looped over the entire list. Oops! */
return 0;
}
return cur_seg;
}
/*
* Move the xHC's endpoint ring dequeue pointer past cur_td.
* Record the new state of the xHC's endpoint ring dequeue segment,
* dequeue pointer, and new consumer cycle state in state.
* Update our internal representation of the ring's dequeue pointer.
*
* We do this in three jumps:
* - First we update our new ring state to be the same as when the xHC stopped.
* - Then we traverse the ring to find the segment that contains
* the last TRB in the TD. We toggle the xHC's new cycle state when we pass
* any link TRBs with the toggle cycle bit set.
* - Finally we move the dequeue state one TRB further, toggling the cycle bit
* if we've moved it past a link TRB with the toggle cycle bit set.
*/
void xhci_find_new_dequeue_state(struct xhci_hcd *xhci,
unsigned int slot_id, unsigned int ep_index,
struct xhci_td *cur_td, struct xhci_dequeue_state *state)
{
struct xhci_virt_device *dev = xhci->devs[slot_id];
struct xhci_ring *ep_ring = dev->ep_rings[ep_index];
struct xhci_generic_trb *trb;
struct xhci_ep_ctx *ep_ctx;
dma_addr_t addr;
state->new_cycle_state = 0;
xhci_dbg(xhci, "Finding segment containing stopped TRB.\n");
state->new_deq_seg = find_trb_seg(cur_td->start_seg,
ep_ring->stopped_trb,
&state->new_cycle_state);
if (!state->new_deq_seg)
BUG();
/* Dig out the cycle state saved by the xHC during the stop ep cmd */
xhci_dbg(xhci, "Finding endpoint context\n");
ep_ctx = xhci_get_ep_ctx(xhci, dev->out_ctx, ep_index);
state->new_cycle_state = 0x1 & ep_ctx->deq;
state->new_deq_ptr = cur_td->last_trb;
xhci_dbg(xhci, "Finding segment containing last TRB in TD.\n");
state->new_deq_seg = find_trb_seg(state->new_deq_seg,
state->new_deq_ptr,
&state->new_cycle_state);
if (!state->new_deq_seg)
BUG();
trb = &state->new_deq_ptr->generic;
if (TRB_TYPE(trb->field[3]) == TRB_LINK &&
(trb->field[3] & LINK_TOGGLE))
state->new_cycle_state = ~(state->new_cycle_state) & 0x1;
next_trb(xhci, ep_ring, &state->new_deq_seg, &state->new_deq_ptr);
/* Don't update the ring cycle state for the producer (us). */
xhci_dbg(xhci, "New dequeue segment = %p (virtual)\n",
state->new_deq_seg);
addr = xhci_trb_virt_to_dma(state->new_deq_seg, state->new_deq_ptr);
xhci_dbg(xhci, "New dequeue pointer = 0x%llx (DMA)\n",
(unsigned long long) addr);
xhci_dbg(xhci, "Setting dequeue pointer in internal ring state.\n");
ep_ring->dequeue = state->new_deq_ptr;
ep_ring->deq_seg = state->new_deq_seg;
}
static void td_to_noop(struct xhci_hcd *xhci, struct xhci_ring *ep_ring,
struct xhci_td *cur_td)
{
struct xhci_segment *cur_seg;
union xhci_trb *cur_trb;
for (cur_seg = cur_td->start_seg, cur_trb = cur_td->first_trb;
true;
next_trb(xhci, ep_ring, &cur_seg, &cur_trb)) {
if ((cur_trb->generic.field[3] & TRB_TYPE_BITMASK) ==
TRB_TYPE(TRB_LINK)) {
/* Unchain any chained Link TRBs, but
* leave the pointers intact.
*/
cur_trb->generic.field[3] &= ~TRB_CHAIN;
xhci_dbg(xhci, "Cancel (unchain) link TRB\n");
xhci_dbg(xhci, "Address = %p (0x%llx dma); "
"in seg %p (0x%llx dma)\n",
cur_trb,
(unsigned long long)xhci_trb_virt_to_dma(cur_seg, cur_trb),
cur_seg,
(unsigned long long)cur_seg->dma);
} else {
cur_trb->generic.field[0] = 0;
cur_trb->generic.field[1] = 0;
cur_trb->generic.field[2] = 0;
/* Preserve only the cycle bit of this TRB */
cur_trb->generic.field[3] &= TRB_CYCLE;
cur_trb->generic.field[3] |= TRB_TYPE(TRB_TR_NOOP);
xhci_dbg(xhci, "Cancel TRB %p (0x%llx dma) "
"in seg %p (0x%llx dma)\n",
cur_trb,
(unsigned long long)xhci_trb_virt_to_dma(cur_seg, cur_trb),
cur_seg,
(unsigned long long)cur_seg->dma);
}
if (cur_trb == cur_td->last_trb)
break;
}
}
static int queue_set_tr_deq(struct xhci_hcd *xhci, int slot_id,
unsigned int ep_index, struct xhci_segment *deq_seg,
union xhci_trb *deq_ptr, u32 cycle_state);
void xhci_queue_new_dequeue_state(struct xhci_hcd *xhci,
struct xhci_ring *ep_ring, unsigned int slot_id,
unsigned int ep_index, struct xhci_dequeue_state *deq_state)
{
xhci_dbg(xhci, "Set TR Deq Ptr cmd, new deq seg = %p (0x%llx dma), "
"new deq ptr = %p (0x%llx dma), new cycle = %u\n",
deq_state->new_deq_seg,
(unsigned long long)deq_state->new_deq_seg->dma,
deq_state->new_deq_ptr,
(unsigned long long)xhci_trb_virt_to_dma(deq_state->new_deq_seg, deq_state->new_deq_ptr),
deq_state->new_cycle_state);
queue_set_tr_deq(xhci, slot_id, ep_index,
deq_state->new_deq_seg,
deq_state->new_deq_ptr,
(u32) deq_state->new_cycle_state);
/* Stop the TD queueing code from ringing the doorbell until
* this command completes. The HC won't set the dequeue pointer
* if the ring is running, and ringing the doorbell starts the
* ring running.
*/
ep_ring->state |= SET_DEQ_PENDING;
xhci_ring_cmd_db(xhci);
}
/*
* When we get a command completion for a Stop Endpoint Command, we need to
* unlink any cancelled TDs from the ring. There are two ways to do that:
*
* 1. If the HW was in the middle of processing the TD that needs to be
* cancelled, then we must move the ring's dequeue pointer past the last TRB
* in the TD with a Set Dequeue Pointer Command.
* 2. Otherwise, we turn all the TRBs in the TD into No-op TRBs (with the chain
* bit cleared) so that the HW will skip over them.
*/
static void handle_stopped_endpoint(struct xhci_hcd *xhci,
union xhci_trb *trb)
{
unsigned int slot_id;
unsigned int ep_index;
struct xhci_ring *ep_ring;
struct list_head *entry;
struct xhci_td *cur_td = 0;
struct xhci_td *last_unlinked_td;
struct xhci_dequeue_state deq_state;
#ifdef CONFIG_USB_HCD_STAT
ktime_t stop_time = ktime_get();
#endif
memset(&deq_state, 0, sizeof(deq_state));
slot_id = TRB_TO_SLOT_ID(trb->generic.field[3]);
ep_index = TRB_TO_EP_INDEX(trb->generic.field[3]);
ep_ring = xhci->devs[slot_id]->ep_rings[ep_index];
if (list_empty(&ep_ring->cancelled_td_list))
return;
/* Fix up the ep ring first, so HW stops executing cancelled TDs.
* We have the xHCI lock, so nothing can modify this list until we drop
* it. We're also in the event handler, so we can't get re-interrupted
* if another Stop Endpoint command completes
*/
list_for_each(entry, &ep_ring->cancelled_td_list) {
cur_td = list_entry(entry, struct xhci_td, cancelled_td_list);
xhci_dbg(xhci, "Cancelling TD starting at %p, 0x%llx (dma).\n",
cur_td->first_trb,
(unsigned long long)xhci_trb_virt_to_dma(cur_td->start_seg, cur_td->first_trb));
/*
* If we stopped on the TD we need to cancel, then we have to
* move the xHC endpoint ring dequeue pointer past this TD.
*/
if (cur_td == ep_ring->stopped_td)
xhci_find_new_dequeue_state(xhci, slot_id, ep_index, cur_td,
&deq_state);
else
td_to_noop(xhci, ep_ring, cur_td);
/*
* The event handler won't see a completion for this TD anymore,
* so remove it from the endpoint ring's TD list. Keep it in
* the cancelled TD list for URB completion later.
*/
list_del(&cur_td->td_list);
ep_ring->cancels_pending--;
}
last_unlinked_td = cur_td;
/* If necessary, queue a Set Transfer Ring Dequeue Pointer command */
if (deq_state.new_deq_ptr && deq_state.new_deq_seg) {
xhci_queue_new_dequeue_state(xhci, ep_ring,
slot_id, ep_index, &deq_state);
} else {
/* Otherwise just ring the doorbell to restart the ring */
ring_ep_doorbell(xhci, slot_id, ep_index);
}
/*
* Drop the lock and complete the URBs in the cancelled TD list.
* New TDs to be cancelled might be added to the end of the list before
* we can complete all the URBs for the TDs we already unlinked.
* So stop when we've completed the URB for the last TD we unlinked.
*/
do {
cur_td = list_entry(ep_ring->cancelled_td_list.next,
struct xhci_td, cancelled_td_list);
list_del(&cur_td->cancelled_td_list);
/* Clean up the cancelled URB */
#ifdef CONFIG_USB_HCD_STAT
hcd_stat_update(xhci->tp_stat, cur_td->urb->actual_length,
ktime_sub(stop_time, cur_td->start_time));
#endif
cur_td->urb->hcpriv = NULL;
usb_hcd_unlink_urb_from_ep(xhci_to_hcd(xhci), cur_td->urb);
xhci_dbg(xhci, "Giveback cancelled URB %p\n", cur_td->urb);
spin_unlock(&xhci->lock);
/* Doesn't matter what we pass for status, since the core will
* just overwrite it (because the URB has been unlinked).
*/
usb_hcd_giveback_urb(xhci_to_hcd(xhci), cur_td->urb, 0);
kfree(cur_td);
spin_lock(&xhci->lock);
} while (cur_td != last_unlinked_td);
/* Return to the event handler with xhci->lock re-acquired */
}
/*
* When we get a completion for a Set Transfer Ring Dequeue Pointer command,
* we need to clear the set deq pending flag in the endpoint ring state, so that
* the TD queueing code can ring the doorbell again. We also need to ring the
* endpoint doorbell to restart the ring, but only if there aren't more
* cancellations pending.
*/
static void handle_set_deq_completion(struct xhci_hcd *xhci,
struct xhci_event_cmd *event,
union xhci_trb *trb)
{
unsigned int slot_id;
unsigned int ep_index;
struct xhci_ring *ep_ring;
struct xhci_virt_device *dev;
struct xhci_ep_ctx *ep_ctx;
struct xhci_slot_ctx *slot_ctx;
slot_id = TRB_TO_SLOT_ID(trb->generic.field[3]);
ep_index = TRB_TO_EP_INDEX(trb->generic.field[3]);
dev = xhci->devs[slot_id];
ep_ring = dev->ep_rings[ep_index];
ep_ctx = xhci_get_ep_ctx(xhci, dev->out_ctx, ep_index);
slot_ctx = xhci_get_slot_ctx(xhci, dev->out_ctx);
if (GET_COMP_CODE(event->status) != COMP_SUCCESS) {
unsigned int ep_state;
unsigned int slot_state;
switch (GET_COMP_CODE(event->status)) {
case COMP_TRB_ERR:
xhci_warn(xhci, "WARN Set TR Deq Ptr cmd invalid because "
"of stream ID configuration\n");
break;
case COMP_CTX_STATE:
xhci_warn(xhci, "WARN Set TR Deq Ptr cmd failed due "
"to incorrect slot or ep state.\n");
ep_state = ep_ctx->ep_info;
ep_state &= EP_STATE_MASK;
slot_state = slot_ctx->dev_state;
slot_state = GET_SLOT_STATE(slot_state);
xhci_dbg(xhci, "Slot state = %u, EP state = %u\n",
slot_state, ep_state);
break;
case COMP_EBADSLT:
xhci_warn(xhci, "WARN Set TR Deq Ptr cmd failed because "
"slot %u was not enabled.\n", slot_id);
break;
default:
xhci_warn(xhci, "WARN Set TR Deq Ptr cmd with unknown "
"completion code of %u.\n",
GET_COMP_CODE(event->status));
break;
}
/* OK what do we do now? The endpoint state is hosed, and we
* should never get to this point if the synchronization between
* queueing, and endpoint state are correct. This might happen
* if the device gets disconnected after we've finished
* cancelling URBs, which might not be an error...
*/
} else {
xhci_dbg(xhci, "Successful Set TR Deq Ptr cmd, deq = @%08llx\n",
ep_ctx->deq);
}
ep_ring->state &= ~SET_DEQ_PENDING;
ring_ep_doorbell(xhci, slot_id, ep_index);
}
static void handle_reset_ep_completion(struct xhci_hcd *xhci,
struct xhci_event_cmd *event,
union xhci_trb *trb)
{
int slot_id;
unsigned int ep_index;
slot_id = TRB_TO_SLOT_ID(trb->generic.field[3]);
ep_index = TRB_TO_EP_INDEX(trb->generic.field[3]);
/* This command will only fail if the endpoint wasn't halted,
* but we don't care.
*/
xhci_dbg(xhci, "Ignoring reset ep completion code of %u\n",
(unsigned int) GET_COMP_CODE(event->status));
/* Clear our internal halted state and restart the ring */
xhci->devs[slot_id]->ep_rings[ep_index]->state &= ~EP_HALTED;
ring_ep_doorbell(xhci, slot_id, ep_index);
}
static void handle_cmd_completion(struct xhci_hcd *xhci,
struct xhci_event_cmd *event)
{
int slot_id = TRB_TO_SLOT_ID(event->flags);
u64 cmd_dma;
dma_addr_t cmd_dequeue_dma;
cmd_dma = event->cmd_trb;
cmd_dequeue_dma = xhci_trb_virt_to_dma(xhci->cmd_ring->deq_seg,
xhci->cmd_ring->dequeue);
/* Is the command ring deq ptr out of sync with the deq seg ptr? */
if (cmd_dequeue_dma == 0) {
xhci->error_bitmask |= 1 << 4;
return;
}
/* Does the DMA address match our internal dequeue pointer address? */
if (cmd_dma != (u64) cmd_dequeue_dma) {
xhci->error_bitmask |= 1 << 5;
return;
}
switch (xhci->cmd_ring->dequeue->generic.field[3] & TRB_TYPE_BITMASK) {
case TRB_TYPE(TRB_ENABLE_SLOT):
if (GET_COMP_CODE(event->status) == COMP_SUCCESS)
xhci->slot_id = slot_id;
else
xhci->slot_id = 0;
complete(&xhci->addr_dev);
break;
case TRB_TYPE(TRB_DISABLE_SLOT):
if (xhci->devs[slot_id])
xhci_free_virt_device(xhci, slot_id);
break;
case TRB_TYPE(TRB_CONFIG_EP):
xhci->devs[slot_id]->cmd_status = GET_COMP_CODE(event->status);
complete(&xhci->devs[slot_id]->cmd_completion);
break;
case TRB_TYPE(TRB_ADDR_DEV):
xhci->devs[slot_id]->cmd_status = GET_COMP_CODE(event->status);
complete(&xhci->addr_dev);
break;
case TRB_TYPE(TRB_STOP_RING):
handle_stopped_endpoint(xhci, xhci->cmd_ring->dequeue);
break;
case TRB_TYPE(TRB_SET_DEQ):
handle_set_deq_completion(xhci, event, xhci->cmd_ring->dequeue);
break;
case TRB_TYPE(TRB_CMD_NOOP):
++xhci->noops_handled;
break;
case TRB_TYPE(TRB_RESET_EP):
handle_reset_ep_completion(xhci, event, xhci->cmd_ring->dequeue);
break;
default:
/* Skip over unknown commands on the event ring */
xhci->error_bitmask |= 1 << 6;
break;
}
inc_deq(xhci, xhci->cmd_ring, false);
}
static void handle_port_status(struct xhci_hcd *xhci,
union xhci_trb *event)
{
u32 port_id;
/* Port status change events always have a successful completion code */
if (GET_COMP_CODE(event->generic.field[2]) != COMP_SUCCESS) {
xhci_warn(xhci, "WARN: xHC returned failed port status event\n");
xhci->error_bitmask |= 1 << 8;
}
/* FIXME: core doesn't care about all port link state changes yet */
port_id = GET_PORT_ID(event->generic.field[0]);
xhci_dbg(xhci, "Port Status Change Event for port %d\n", port_id);
/* Update event ring dequeue pointer before dropping the lock */
inc_deq(xhci, xhci->event_ring, true);
xhci_set_hc_event_deq(xhci);
spin_unlock(&xhci->lock);
/* Pass this up to the core */
usb_hcd_poll_rh_status(xhci_to_hcd(xhci));
spin_lock(&xhci->lock);
}
/*
* This TD is defined by the TRBs starting at start_trb in start_seg and ending
* at end_trb, which may be in another segment. If the suspect DMA address is a
* TRB in this TD, this function returns that TRB's segment. Otherwise it
* returns 0.
*/
static struct xhci_segment *trb_in_td(
struct xhci_segment *start_seg,
union xhci_trb *start_trb,
union xhci_trb *end_trb,
dma_addr_t suspect_dma)
{
dma_addr_t start_dma;
dma_addr_t end_seg_dma;
dma_addr_t end_trb_dma;
struct xhci_segment *cur_seg;
start_dma = xhci_trb_virt_to_dma(start_seg, start_trb);
cur_seg = start_seg;
do {
/* We may get an event for a Link TRB in the middle of a TD */
end_seg_dma = xhci_trb_virt_to_dma(cur_seg,
&start_seg->trbs[TRBS_PER_SEGMENT - 1]);
/* If the end TRB isn't in this segment, this is set to 0 */
end_trb_dma = xhci_trb_virt_to_dma(cur_seg, end_trb);
if (end_trb_dma > 0) {
/* The end TRB is in this segment, so suspect should be here */
if (start_dma <= end_trb_dma) {
if (suspect_dma >= start_dma && suspect_dma <= end_trb_dma)
return cur_seg;
} else {
/* Case for one segment with
* a TD wrapped around to the top
*/
if ((suspect_dma >= start_dma &&
suspect_dma <= end_seg_dma) ||
(suspect_dma >= cur_seg->dma &&
suspect_dma <= end_trb_dma))
return cur_seg;
}
return 0;
} else {
/* Might still be somewhere in this segment */
if (suspect_dma >= start_dma && suspect_dma <= end_seg_dma)
return cur_seg;
}
cur_seg = cur_seg->next;
start_dma = xhci_trb_virt_to_dma(cur_seg, &cur_seg->trbs[0]);
} while (1);
}
/*
* If this function returns an error condition, it means it got a Transfer
* event with a corrupted Slot ID, Endpoint ID, or TRB DMA address.
* At this point, the host controller is probably hosed and should be reset.
*/
static int handle_tx_event(struct xhci_hcd *xhci,
struct xhci_transfer_event *event)
{
struct xhci_virt_device *xdev;
struct xhci_ring *ep_ring;
int ep_index;
struct xhci_td *td = 0;
dma_addr_t event_dma;
struct xhci_segment *event_seg;
union xhci_trb *event_trb;
struct urb *urb = 0;
int status = -EINPROGRESS;
struct xhci_ep_ctx *ep_ctx;
xhci_dbg(xhci, "In %s\n", __func__);
xdev = xhci->devs[TRB_TO_SLOT_ID(event->flags)];
if (!xdev) {
xhci_err(xhci, "ERROR Transfer event pointed to bad slot\n");
return -ENODEV;
}
/* Endpoint ID is 1 based, our index is zero based */
ep_index = TRB_TO_EP_ID(event->flags) - 1;
xhci_dbg(xhci, "%s - ep index = %d\n", __func__, ep_index);
ep_ring = xdev->ep_rings[ep_index];
ep_ctx = xhci_get_ep_ctx(xhci, xdev->out_ctx, ep_index);
if (!ep_ring || (ep_ctx->ep_info & EP_STATE_MASK) == EP_STATE_DISABLED) {
xhci_err(xhci, "ERROR Transfer event pointed to disabled endpoint\n");
return -ENODEV;
}
event_dma = event->buffer;
/* This TRB should be in the TD at the head of this ring's TD list */
xhci_dbg(xhci, "%s - checking for list empty\n", __func__);
if (list_empty(&ep_ring->td_list)) {
xhci_warn(xhci, "WARN Event TRB for slot %d ep %d with no TDs queued?\n",
TRB_TO_SLOT_ID(event->flags), ep_index);
xhci_dbg(xhci, "Event TRB with TRB type ID %u\n",
(unsigned int) (event->flags & TRB_TYPE_BITMASK)>>10);
xhci_print_trb_offsets(xhci, (union xhci_trb *) event);
urb = NULL;
goto cleanup;
}
xhci_dbg(xhci, "%s - getting list entry\n", __func__);
td = list_entry(ep_ring->td_list.next, struct xhci_td, td_list);
/* Is this a TRB in the currently executing TD? */
xhci_dbg(xhci, "%s - looking for TD\n", __func__);
event_seg = trb_in_td(ep_ring->deq_seg, ep_ring->dequeue,
td->last_trb, event_dma);
xhci_dbg(xhci, "%s - found event_seg = %p\n", __func__, event_seg);
if (!event_seg) {
/* HC is busted, give up! */
xhci_err(xhci, "ERROR Transfer event TRB DMA ptr not part of current TD\n");
return -ESHUTDOWN;
}
event_trb = &event_seg->trbs[(event_dma - event_seg->dma) / sizeof(*event_trb)];
xhci_dbg(xhci, "Event TRB with TRB type ID %u\n",
(unsigned int) (event->flags & TRB_TYPE_BITMASK)>>10);
xhci_dbg(xhci, "Offset 0x00 (buffer lo) = 0x%x\n",
lower_32_bits(event->buffer));
xhci_dbg(xhci, "Offset 0x04 (buffer hi) = 0x%x\n",
upper_32_bits(event->buffer));
xhci_dbg(xhci, "Offset 0x08 (transfer length) = 0x%x\n",
(unsigned int) event->transfer_len);
xhci_dbg(xhci, "Offset 0x0C (flags) = 0x%x\n",
(unsigned int) event->flags);
/* Look for common error cases */
switch (GET_COMP_CODE(event->transfer_len)) {
/* Skip codes that require special handling depending on
* transfer type
*/
case COMP_SUCCESS:
case COMP_SHORT_TX:
break;
case COMP_STOP:
xhci_dbg(xhci, "Stopped on Transfer TRB\n");
break;
case COMP_STOP_INVAL:
xhci_dbg(xhci, "Stopped on No-op or Link TRB\n");
break;
case COMP_STALL:
xhci_warn(xhci, "WARN: Stalled endpoint\n");
ep_ring->state |= EP_HALTED;
status = -EPIPE;
break;
case COMP_TRB_ERR:
xhci_warn(xhci, "WARN: TRB error on endpoint\n");
status = -EILSEQ;
break;
case COMP_TX_ERR:
xhci_warn(xhci, "WARN: transfer error on endpoint\n");
status = -EPROTO;
break;
case COMP_BABBLE:
xhci_warn(xhci, "WARN: babble error on endpoint\n");
status = -EOVERFLOW;
break;
case COMP_DB_ERR:
xhci_warn(xhci, "WARN: HC couldn't access mem fast enough\n");
status = -ENOSR;
break;
default:
xhci_warn(xhci, "ERROR Unknown event condition, HC probably busted\n");
urb = NULL;
goto cleanup;
}
/* Now update the urb's actual_length and give back to the core */
/* Was this a control transfer? */
if (usb_endpoint_xfer_control(&td->urb->ep->desc)) {
xhci_debug_trb(xhci, xhci->event_ring->dequeue);
switch (GET_COMP_CODE(event->transfer_len)) {
case COMP_SUCCESS:
if (event_trb == ep_ring->dequeue) {
xhci_warn(xhci, "WARN: Success on ctrl setup TRB without IOC set??\n");
status = -ESHUTDOWN;
} else if (event_trb != td->last_trb) {
xhci_warn(xhci, "WARN: Success on ctrl data TRB without IOC set??\n");
status = -ESHUTDOWN;
} else {
xhci_dbg(xhci, "Successful control transfer!\n");
status = 0;
}
break;
case COMP_SHORT_TX:
xhci_warn(xhci, "WARN: short transfer on control ep\n");
status = -EREMOTEIO;
break;
default:
/* Others already handled above */
break;
}
/*
* Did we transfer any data, despite the errors that might have
* happened? I.e. did we get past the setup stage?
*/
if (event_trb != ep_ring->dequeue) {
/* The event was for the status stage */
if (event_trb == td->last_trb) {
if (td->urb->actual_length != 0) {
/* Don't overwrite a previously set error code */
if (status == -EINPROGRESS || status == 0)
/* Did we already see a short data stage? */
status = -EREMOTEIO;
} else {
td->urb->actual_length =
td->urb->transfer_buffer_length;
}
} else {
/* Maybe the event was for the data stage? */
if (GET_COMP_CODE(event->transfer_len) != COMP_STOP_INVAL) {
/* We didn't stop on a link TRB in the middle */
td->urb->actual_length =
td->urb->transfer_buffer_length -
TRB_LEN(event->transfer_len);
xhci_dbg(xhci, "Waiting for status stage event\n");
urb = NULL;
goto cleanup;
}
}
}
} else {
switch (GET_COMP_CODE(event->transfer_len)) {
case COMP_SUCCESS:
/* Double check that the HW transferred everything. */
if (event_trb != td->last_trb) {
xhci_warn(xhci, "WARN Successful completion "
"on short TX\n");
if (td->urb->transfer_flags & URB_SHORT_NOT_OK)
status = -EREMOTEIO;
else
status = 0;
} else {
xhci_dbg(xhci, "Successful bulk transfer!\n");
status = 0;
}
break;
case COMP_SHORT_TX:
if (td->urb->transfer_flags & URB_SHORT_NOT_OK)
status = -EREMOTEIO;
else
status = 0;
break;
default:
/* Others already handled above */
break;
}
dev_dbg(&td->urb->dev->dev,
"ep %#x - asked for %d bytes, "
"%d bytes untransferred\n",
td->urb->ep->desc.bEndpointAddress,
td->urb->transfer_buffer_length,
TRB_LEN(event->transfer_len));
/* Fast path - was this the last TRB in the TD for this URB? */
if (event_trb == td->last_trb) {
if (TRB_LEN(event->transfer_len) != 0) {
td->urb->actual_length =
td->urb->transfer_buffer_length -
TRB_LEN(event->transfer_len);
if (td->urb->actual_length < 0) {
xhci_warn(xhci, "HC gave bad length "
"of %d bytes left\n",
TRB_LEN(event->transfer_len));
td->urb->actual_length = 0;
}
/* Don't overwrite a previously set error code */
if (status == -EINPROGRESS) {
if (td->urb->transfer_flags & URB_SHORT_NOT_OK)
status = -EREMOTEIO;
else
status = 0;
}
} else {
td->urb->actual_length = td->urb->transfer_buffer_length;
/* Ignore a short packet completion if the
* untransferred length was zero.
*/
if (status == -EREMOTEIO)
status = 0;
}
} else {
/* Slow path - walk the list, starting from the dequeue
* pointer, to get the actual length transferred.
*/
union xhci_trb *cur_trb;
struct xhci_segment *cur_seg;
td->urb->actual_length = 0;
for (cur_trb = ep_ring->dequeue, cur_seg = ep_ring->deq_seg;
cur_trb != event_trb;
next_trb(xhci, ep_ring, &cur_seg, &cur_trb)) {
if (TRB_TYPE(cur_trb->generic.field[3]) != TRB_TR_NOOP &&
TRB_TYPE(cur_trb->generic.field[3]) != TRB_LINK)
td->urb->actual_length +=
TRB_LEN(cur_trb->generic.field[2]);
}
/* If the ring didn't stop on a Link or No-op TRB, add
* in the actual bytes transferred from the Normal TRB
*/
if (GET_COMP_CODE(event->transfer_len) != COMP_STOP_INVAL)
td->urb->actual_length +=
TRB_LEN(cur_trb->generic.field[2]) -
TRB_LEN(event->transfer_len);
}
}
if (GET_COMP_CODE(event->transfer_len) == COMP_STOP_INVAL ||
GET_COMP_CODE(event->transfer_len) == COMP_STOP) {
/* The Endpoint Stop Command completion will take care of any
* stopped TDs. A stopped TD may be restarted, so don't update
* the ring dequeue pointer or take this TD off any lists yet.
*/
ep_ring->stopped_td = td;
ep_ring->stopped_trb = event_trb;
} else {
if (GET_COMP_CODE(event->transfer_len) == COMP_STALL) {
/* The transfer is completed from the driver's
* perspective, but we need to issue a set dequeue
* command for this stalled endpoint to move the dequeue
* pointer past the TD. We can't do that here because
* the halt condition must be cleared first.
*/
ep_ring->stopped_td = td;
ep_ring->stopped_trb = event_trb;
} else {
/* Update ring dequeue pointer */
while (ep_ring->dequeue != td->last_trb)
inc_deq(xhci, ep_ring, false);
inc_deq(xhci, ep_ring, false);
}
/* Clean up the endpoint's TD list */
urb = td->urb;
list_del(&td->td_list);
/* Was this TD slated to be cancelled but completed anyway? */
if (!list_empty(&td->cancelled_td_list)) {
list_del(&td->cancelled_td_list);
ep_ring->cancels_pending--;
}
/* Leave the TD around for the reset endpoint function to use */
if (GET_COMP_CODE(event->transfer_len) != COMP_STALL) {
kfree(td);
}
urb->hcpriv = NULL;
}
cleanup:
inc_deq(xhci, xhci->event_ring, true);
xhci_set_hc_event_deq(xhci);
/* FIXME for multi-TD URBs (who have buffers bigger than 64MB) */
if (urb) {
usb_hcd_unlink_urb_from_ep(xhci_to_hcd(xhci), urb);
xhci_dbg(xhci, "Giveback URB %p, len = %d, status = %d\n",
urb, td->urb->actual_length, status);
spin_unlock(&xhci->lock);
usb_hcd_giveback_urb(xhci_to_hcd(xhci), urb, status);
spin_lock(&xhci->lock);
}
return 0;
}
/*
* This function handles all OS-owned events on the event ring. It may drop
* xhci->lock between event processing (e.g. to pass up port status changes).
*/
void xhci_handle_event(struct xhci_hcd *xhci)
{
union xhci_trb *event;
int update_ptrs = 1;
int ret;
xhci_dbg(xhci, "In %s\n", __func__);
if (!xhci->event_ring || !xhci->event_ring->dequeue) {
xhci->error_bitmask |= 1 << 1;
return;
}
event = xhci->event_ring->dequeue;
/* Does the HC or OS own the TRB? */
if ((event->event_cmd.flags & TRB_CYCLE) !=
xhci->event_ring->cycle_state) {
xhci->error_bitmask |= 1 << 2;
return;
}
xhci_dbg(xhci, "%s - OS owns TRB\n", __func__);
/* FIXME: Handle more event types. */
switch ((event->event_cmd.flags & TRB_TYPE_BITMASK)) {
case TRB_TYPE(TRB_COMPLETION):
xhci_dbg(xhci, "%s - calling handle_cmd_completion\n", __func__);
handle_cmd_completion(xhci, &event->event_cmd);
xhci_dbg(xhci, "%s - returned from handle_cmd_completion\n", __func__);
break;
case TRB_TYPE(TRB_PORT_STATUS):
xhci_dbg(xhci, "%s - calling handle_port_status\n", __func__);
handle_port_status(xhci, event);
xhci_dbg(xhci, "%s - returned from handle_port_status\n", __func__);
update_ptrs = 0;
break;
case TRB_TYPE(TRB_TRANSFER):
xhci_dbg(xhci, "%s - calling handle_tx_event\n", __func__);
ret = handle_tx_event(xhci, &event->trans_event);
xhci_dbg(xhci, "%s - returned from handle_tx_event\n", __func__);
if (ret < 0)
xhci->error_bitmask |= 1 << 9;
else
update_ptrs = 0;
break;
default:
xhci->error_bitmask |= 1 << 3;
}
if (update_ptrs) {
/* Update SW and HC event ring dequeue pointer */
inc_deq(xhci, xhci->event_ring, true);
xhci_set_hc_event_deq(xhci);
}
/* Are there more items on the event ring? */
xhci_handle_event(xhci);
}
/**** Endpoint Ring Operations ****/
/*
* Generic function for queueing a TRB on a ring.
* The caller must have checked to make sure there's room on the ring.
*/
static void queue_trb(struct xhci_hcd *xhci, struct xhci_ring *ring,
bool consumer,
u32 field1, u32 field2, u32 field3, u32 field4)
{
struct xhci_generic_trb *trb;
trb = &ring->enqueue->generic;
trb->field[0] = field1;
trb->field[1] = field2;
trb->field[2] = field3;
trb->field[3] = field4;
inc_enq(xhci, ring, consumer);
}
/*
* Does various checks on the endpoint ring, and makes it ready to queue num_trbs.
* FIXME allocate segments if the ring is full.
*/
static int prepare_ring(struct xhci_hcd *xhci, struct xhci_ring *ep_ring,
u32 ep_state, unsigned int num_trbs, gfp_t mem_flags)
{
/* Make sure the endpoint has been added to xHC schedule */
xhci_dbg(xhci, "Endpoint state = 0x%x\n", ep_state);
switch (ep_state) {
case EP_STATE_DISABLED:
/*
* USB core changed config/interfaces without notifying us,
* or hardware is reporting the wrong state.
*/
xhci_warn(xhci, "WARN urb submitted to disabled ep\n");
return -ENOENT;
case EP_STATE_ERROR:
xhci_warn(xhci, "WARN waiting for error on ep to be cleared\n");
/* FIXME event handling code for error needs to clear it */
/* XXX not sure if this should be -ENOENT or not */
return -EINVAL;
case EP_STATE_HALTED:
xhci_dbg(xhci, "WARN halted endpoint, queueing URB anyway.\n");
case EP_STATE_STOPPED:
case EP_STATE_RUNNING:
break;
default:
xhci_err(xhci, "ERROR unknown endpoint state for ep\n");
/*
* FIXME issue Configure Endpoint command to try to get the HC
* back into a known state.
*/
return -EINVAL;
}
if (!room_on_ring(xhci, ep_ring, num_trbs)) {
/* FIXME allocate more room */
xhci_err(xhci, "ERROR no room on ep ring\n");
return -ENOMEM;
}
return 0;
}
static int prepare_transfer(struct xhci_hcd *xhci,
struct xhci_virt_device *xdev,
unsigned int ep_index,
unsigned int num_trbs,
struct urb *urb,
struct xhci_td **td,
gfp_t mem_flags)
{
int ret;
struct xhci_ep_ctx *ep_ctx = xhci_get_ep_ctx(xhci, xdev->out_ctx, ep_index);
ret = prepare_ring(xhci, xdev->ep_rings[ep_index],
ep_ctx->ep_info & EP_STATE_MASK,
num_trbs, mem_flags);
if (ret)
return ret;
*td = kzalloc(sizeof(struct xhci_td), mem_flags);
if (!*td)
return -ENOMEM;
INIT_LIST_HEAD(&(*td)->td_list);
INIT_LIST_HEAD(&(*td)->cancelled_td_list);
ret = usb_hcd_link_urb_to_ep(xhci_to_hcd(xhci), urb);
if (unlikely(ret)) {
kfree(*td);
return ret;
}
(*td)->urb = urb;
urb->hcpriv = (void *) (*td);
/* Add this TD to the tail of the endpoint ring's TD list */
list_add_tail(&(*td)->td_list, &xdev->ep_rings[ep_index]->td_list);
(*td)->start_seg = xdev->ep_rings[ep_index]->enq_seg;
(*td)->first_trb = xdev->ep_rings[ep_index]->enqueue;
return 0;
}
static unsigned int count_sg_trbs_needed(struct xhci_hcd *xhci, struct urb *urb)
{
int num_sgs, num_trbs, running_total, temp, i;
struct scatterlist *sg;
sg = NULL;
num_sgs = urb->num_sgs;
temp = urb->transfer_buffer_length;
xhci_dbg(xhci, "count sg list trbs: \n");
num_trbs = 0;
for_each_sg(urb->sg->sg, sg, num_sgs, i) {
unsigned int previous_total_trbs = num_trbs;
unsigned int len = sg_dma_len(sg);
/* Scatter gather list entries may cross 64KB boundaries */
running_total = TRB_MAX_BUFF_SIZE -
(sg_dma_address(sg) & ((1 << TRB_MAX_BUFF_SHIFT) - 1));
if (running_total != 0)
num_trbs++;
/* How many more 64KB chunks to transfer, how many more TRBs? */
while (running_total < sg_dma_len(sg)) {
num_trbs++;
running_total += TRB_MAX_BUFF_SIZE;
}
xhci_dbg(xhci, " sg #%d: dma = %#llx, len = %#x (%d), num_trbs = %d\n",
i, (unsigned long long)sg_dma_address(sg),
len, len, num_trbs - previous_total_trbs);
len = min_t(int, len, temp);
temp -= len;
if (temp == 0)
break;
}
xhci_dbg(xhci, "\n");
if (!in_interrupt())
dev_dbg(&urb->dev->dev, "ep %#x - urb len = %d, sglist used, num_trbs = %d\n",
urb->ep->desc.bEndpointAddress,
urb->transfer_buffer_length,
num_trbs);
return num_trbs;
}
static void check_trb_math(struct urb *urb, int num_trbs, int running_total)
{
if (num_trbs != 0)
dev_dbg(&urb->dev->dev, "%s - ep %#x - Miscalculated number of "
"TRBs, %d left\n", __func__,
urb->ep->desc.bEndpointAddress, num_trbs);
if (running_total != urb->transfer_buffer_length)
dev_dbg(&urb->dev->dev, "%s - ep %#x - Miscalculated tx length, "
"queued %#x (%d), asked for %#x (%d)\n",
__func__,
urb->ep->desc.bEndpointAddress,
running_total, running_total,
urb->transfer_buffer_length,
urb->transfer_buffer_length);
}
static void giveback_first_trb(struct xhci_hcd *xhci, int slot_id,
unsigned int ep_index, int start_cycle,
struct xhci_generic_trb *start_trb, struct xhci_td *td)
{
/*
* Pass all the TRBs to the hardware at once and make sure this write
* isn't reordered.
*/
wmb();
start_trb->field[3] |= start_cycle;
ring_ep_doorbell(xhci, slot_id, ep_index);
}
static int queue_bulk_sg_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
struct urb *urb, int slot_id, unsigned int ep_index)
{
struct xhci_ring *ep_ring;
unsigned int num_trbs;
struct xhci_td *td;
struct scatterlist *sg;
int num_sgs;
int trb_buff_len, this_sg_len, running_total;
bool first_trb;
u64 addr;
struct xhci_generic_trb *start_trb;
int start_cycle;
ep_ring = xhci->devs[slot_id]->ep_rings[ep_index];
num_trbs = count_sg_trbs_needed(xhci, urb);
num_sgs = urb->num_sgs;
trb_buff_len = prepare_transfer(xhci, xhci->devs[slot_id],
ep_index, num_trbs, urb, &td, mem_flags);
if (trb_buff_len < 0)
return trb_buff_len;
/*
* Don't give the first TRB to the hardware (by toggling the cycle bit)
* until we've finished creating all the other TRBs. The ring's cycle
* state may change as we enqueue the other TRBs, so save it too.
*/
start_trb = &ep_ring->enqueue->generic;
start_cycle = ep_ring->cycle_state;
running_total = 0;
/*
* How much data is in the first TRB?
*
* There are three forces at work for TRB buffer pointers and lengths:
* 1. We don't want to walk off the end of this sg-list entry buffer.
* 2. The transfer length that the driver requested may be smaller than
* the amount of memory allocated for this scatter-gather list.
* 3. TRBs buffers can't cross 64KB boundaries.
*/
sg = urb->sg->sg;
addr = (u64) sg_dma_address(sg);
this_sg_len = sg_dma_len(sg);
trb_buff_len = TRB_MAX_BUFF_SIZE -
(addr & ((1 << TRB_MAX_BUFF_SHIFT) - 1));
trb_buff_len = min_t(int, trb_buff_len, this_sg_len);
if (trb_buff_len > urb->transfer_buffer_length)
trb_buff_len = urb->transfer_buffer_length;
xhci_dbg(xhci, "First length to xfer from 1st sglist entry = %u\n",
trb_buff_len);
first_trb = true;
/* Queue the first TRB, even if it's zero-length */
do {
u32 field = 0;
u32 length_field = 0;
/* Don't change the cycle bit of the first TRB until later */
if (first_trb)
first_trb = false;
else
field |= ep_ring->cycle_state;
/* Chain all the TRBs together; clear the chain bit in the last
* TRB to indicate it's the last TRB in the chain.
*/
if (num_trbs > 1) {
field |= TRB_CHAIN;
} else {
/* FIXME - add check for ZERO_PACKET flag before this */
td->last_trb = ep_ring->enqueue;
field |= TRB_IOC;
}
xhci_dbg(xhci, " sg entry: dma = %#x, len = %#x (%d), "
"64KB boundary at %#x, end dma = %#x\n",
(unsigned int) addr, trb_buff_len, trb_buff_len,
(unsigned int) (addr + TRB_MAX_BUFF_SIZE) & ~(TRB_MAX_BUFF_SIZE - 1),
(unsigned int) addr + trb_buff_len);
if (TRB_MAX_BUFF_SIZE -
(addr & ((1 << TRB_MAX_BUFF_SHIFT) - 1)) < trb_buff_len) {
xhci_warn(xhci, "WARN: sg dma xfer crosses 64KB boundaries!\n");
xhci_dbg(xhci, "Next boundary at %#x, end dma = %#x\n",
(unsigned int) (addr + TRB_MAX_BUFF_SIZE) & ~(TRB_MAX_BUFF_SIZE - 1),
(unsigned int) addr + trb_buff_len);
}
length_field = TRB_LEN(trb_buff_len) |
TD_REMAINDER(urb->transfer_buffer_length - running_total) |
TRB_INTR_TARGET(0);
queue_trb(xhci, ep_ring, false,
lower_32_bits(addr),
upper_32_bits(addr),
length_field,
/* We always want to know if the TRB was short,
* or we won't get an event when it completes.
* (Unless we use event data TRBs, which are a
* waste of space and HC resources.)
*/
field | TRB_ISP | TRB_TYPE(TRB_NORMAL));
--num_trbs;
running_total += trb_buff_len;
/* Calculate length for next transfer --
* Are we done queueing all the TRBs for this sg entry?
*/
this_sg_len -= trb_buff_len;
if (this_sg_len == 0) {
--num_sgs;
if (num_sgs == 0)
break;
sg = sg_next(sg);
addr = (u64) sg_dma_address(sg);
this_sg_len = sg_dma_len(sg);
} else {
addr += trb_buff_len;
}
trb_buff_len = TRB_MAX_BUFF_SIZE -
(addr & ((1 << TRB_MAX_BUFF_SHIFT) - 1));
trb_buff_len = min_t(int, trb_buff_len, this_sg_len);
if (running_total + trb_buff_len > urb->transfer_buffer_length)
trb_buff_len =
urb->transfer_buffer_length - running_total;
} while (running_total < urb->transfer_buffer_length);
check_trb_math(urb, num_trbs, running_total);
giveback_first_trb(xhci, slot_id, ep_index, start_cycle, start_trb, td);
return 0;
}
/* This is very similar to what ehci-q.c qtd_fill() does */
int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
struct urb *urb, int slot_id, unsigned int ep_index)
{
struct xhci_ring *ep_ring;
struct xhci_td *td;
int num_trbs;
struct xhci_generic_trb *start_trb;
bool first_trb;
int start_cycle;
u32 field, length_field;
int running_total, trb_buff_len, ret;
u64 addr;
if (urb->sg)
return queue_bulk_sg_tx(xhci, mem_flags, urb, slot_id, ep_index);
ep_ring = xhci->devs[slot_id]->ep_rings[ep_index];
num_trbs = 0;
/* How much data is (potentially) left before the 64KB boundary? */
running_total = TRB_MAX_BUFF_SIZE -
(urb->transfer_dma & ((1 << TRB_MAX_BUFF_SHIFT) - 1));
/* If there's some data on this 64KB chunk, or we have to send a
* zero-length transfer, we need at least one TRB
*/
if (running_total != 0 || urb->transfer_buffer_length == 0)
num_trbs++;
/* How many more 64KB chunks to transfer, how many more TRBs? */
while (running_total < urb->transfer_buffer_length) {
num_trbs++;
running_total += TRB_MAX_BUFF_SIZE;
}
/* FIXME: this doesn't deal with URB_ZERO_PACKET - need one more */
if (!in_interrupt())
dev_dbg(&urb->dev->dev, "ep %#x - urb len = %#x (%d), addr = %#llx, num_trbs = %d\n",
urb->ep->desc.bEndpointAddress,
urb->transfer_buffer_length,
urb->transfer_buffer_length,
(unsigned long long)urb->transfer_dma,
num_trbs);
ret = prepare_transfer(xhci, xhci->devs[slot_id], ep_index,
num_trbs, urb, &td, mem_flags);
if (ret < 0)
return ret;
/*
* Don't give the first TRB to the hardware (by toggling the cycle bit)
* until we've finished creating all the other TRBs. The ring's cycle
* state may change as we enqueue the other TRBs, so save it too.
*/
start_trb = &ep_ring->enqueue->generic;
start_cycle = ep_ring->cycle_state;
running_total = 0;
/* How much data is in the first TRB? */
addr = (u64) urb->transfer_dma;
trb_buff_len = TRB_MAX_BUFF_SIZE -
(urb->transfer_dma & ((1 << TRB_MAX_BUFF_SHIFT) - 1));
if (urb->transfer_buffer_length < trb_buff_len)
trb_buff_len = urb->transfer_buffer_length;
first_trb = true;
/* Queue the first TRB, even if it's zero-length */
do {
field = 0;
/* Don't change the cycle bit of the first TRB until later */
if (first_trb)
first_trb = false;
else
field |= ep_ring->cycle_state;
/* Chain all the TRBs together; clear the chain bit in the last
* TRB to indicate it's the last TRB in the chain.
*/
if (num_trbs > 1) {
field |= TRB_CHAIN;
} else {
/* FIXME - add check for ZERO_PACKET flag before this */
td->last_trb = ep_ring->enqueue;
field |= TRB_IOC;
}
length_field = TRB_LEN(trb_buff_len) |
TD_REMAINDER(urb->transfer_buffer_length - running_total) |
TRB_INTR_TARGET(0);
queue_trb(xhci, ep_ring, false,
lower_32_bits(addr),
upper_32_bits(addr),
length_field,
/* We always want to know if the TRB was short,
* or we won't get an event when it completes.
* (Unless we use event data TRBs, which are a
* waste of space and HC resources.)
*/
field | TRB_ISP | TRB_TYPE(TRB_NORMAL));
--num_trbs;
running_total += trb_buff_len;
/* Calculate length for next transfer */
addr += trb_buff_len;
trb_buff_len = urb->transfer_buffer_length - running_total;
if (trb_buff_len > TRB_MAX_BUFF_SIZE)
trb_buff_len = TRB_MAX_BUFF_SIZE;
} while (running_total < urb->transfer_buffer_length);
check_trb_math(urb, num_trbs, running_total);
giveback_first_trb(xhci, slot_id, ep_index, start_cycle, start_trb, td);
return 0;
}
/* Caller must have locked xhci->lock */
int xhci_queue_ctrl_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
struct urb *urb, int slot_id, unsigned int ep_index)
{
struct xhci_ring *ep_ring;
int num_trbs;
int ret;
struct usb_ctrlrequest *setup;
struct xhci_generic_trb *start_trb;
int start_cycle;
u32 field, length_field;
struct xhci_td *td;
ep_ring = xhci->devs[slot_id]->ep_rings[ep_index];
/*
* Need to copy setup packet into setup TRB, so we can't use the setup
* DMA address.
*/
if (!urb->setup_packet)
return -EINVAL;
if (!in_interrupt())
xhci_dbg(xhci, "Queueing ctrl tx for slot id %d, ep %d\n",
slot_id, ep_index);
/* 1 TRB for setup, 1 for status */
num_trbs = 2;
/*
* Don't need to check if we need additional event data and normal TRBs,
* since data in control transfers will never get bigger than 16MB
* XXX: can we get a buffer that crosses 64KB boundaries?
*/
if (urb->transfer_buffer_length > 0)
num_trbs++;
ret = prepare_transfer(xhci, xhci->devs[slot_id], ep_index, num_trbs,
urb, &td, mem_flags);
if (ret < 0)
return ret;
/*
* Don't give the first TRB to the hardware (by toggling the cycle bit)
* until we've finished creating all the other TRBs. The ring's cycle
* state may change as we enqueue the other TRBs, so save it too.
*/
start_trb = &ep_ring->enqueue->generic;
start_cycle = ep_ring->cycle_state;
/* Queue setup TRB - see section 6.4.1.2.1 */
/* FIXME better way to translate setup_packet into two u32 fields? */
setup = (struct usb_ctrlrequest *) urb->setup_packet;
queue_trb(xhci, ep_ring, false,
/* FIXME endianness is probably going to bite my ass here. */
setup->bRequestType | setup->bRequest << 8 | setup->wValue << 16,
setup->wIndex | setup->wLength << 16,
TRB_LEN(8) | TRB_INTR_TARGET(0),
/* Immediate data in pointer */
TRB_IDT | TRB_TYPE(TRB_SETUP));
/* If there's data, queue data TRBs */
field = 0;
length_field = TRB_LEN(urb->transfer_buffer_length) |
TD_REMAINDER(urb->transfer_buffer_length) |
TRB_INTR_TARGET(0);
if (urb->transfer_buffer_length > 0) {
if (setup->bRequestType & USB_DIR_IN)
field |= TRB_DIR_IN;
queue_trb(xhci, ep_ring, false,
lower_32_bits(urb->transfer_dma),
upper_32_bits(urb->transfer_dma),
length_field,
/* Event on short tx */
field | TRB_ISP | TRB_TYPE(TRB_DATA) | ep_ring->cycle_state);
}
/* Save the DMA address of the last TRB in the TD */
td->last_trb = ep_ring->enqueue;
/* Queue status TRB - see Table 7 and sections 4.11.2.2 and 6.4.1.2.3 */
/* If the device sent data, the status stage is an OUT transfer */
if (urb->transfer_buffer_length > 0 && setup->bRequestType & USB_DIR_IN)
field = 0;
else
field = TRB_DIR_IN;
queue_trb(xhci, ep_ring, false,
0,
0,
TRB_INTR_TARGET(0),
/* Event on completion */
field | TRB_IOC | TRB_TYPE(TRB_STATUS) | ep_ring->cycle_state);
giveback_first_trb(xhci, slot_id, ep_index, start_cycle, start_trb, td);
return 0;
}
/**** Command Ring Operations ****/
/* Generic function for queueing a command TRB on the command ring */
static int queue_command(struct xhci_hcd *xhci, u32 field1, u32 field2, u32 field3, u32 field4)
{
if (!room_on_ring(xhci, xhci->cmd_ring, 1)) {
if (!in_interrupt())
xhci_err(xhci, "ERR: No room for command on command ring\n");
return -ENOMEM;
}
queue_trb(xhci, xhci->cmd_ring, false, field1, field2, field3,
field4 | xhci->cmd_ring->cycle_state);
return 0;
}
/* Queue a no-op command on the command ring */
static int queue_cmd_noop(struct xhci_hcd *xhci)
{
return queue_command(xhci, 0, 0, 0, TRB_TYPE(TRB_CMD_NOOP));
}
/*
* Place a no-op command on the command ring to test the command and
* event ring.
*/
void *xhci_setup_one_noop(struct xhci_hcd *xhci)
{
if (queue_cmd_noop(xhci) < 0)
return NULL;
xhci->noops_submitted++;
return xhci_ring_cmd_db;
}
/* Queue a slot enable or disable request on the command ring */
int xhci_queue_slot_control(struct xhci_hcd *xhci, u32 trb_type, u32 slot_id)
{
return queue_command(xhci, 0, 0, 0,
TRB_TYPE(trb_type) | SLOT_ID_FOR_TRB(slot_id));
}
/* Queue an address device command TRB */
int xhci_queue_address_device(struct xhci_hcd *xhci, dma_addr_t in_ctx_ptr,
u32 slot_id)
{
return queue_command(xhci, lower_32_bits(in_ctx_ptr),
upper_32_bits(in_ctx_ptr), 0,
TRB_TYPE(TRB_ADDR_DEV) | SLOT_ID_FOR_TRB(slot_id));
}
/* Queue a configure endpoint command TRB */
int xhci_queue_configure_endpoint(struct xhci_hcd *xhci, dma_addr_t in_ctx_ptr,
u32 slot_id)
{
return queue_command(xhci, lower_32_bits(in_ctx_ptr),
upper_32_bits(in_ctx_ptr), 0,
TRB_TYPE(TRB_CONFIG_EP) | SLOT_ID_FOR_TRB(slot_id));
}
int xhci_queue_stop_endpoint(struct xhci_hcd *xhci, int slot_id,
unsigned int ep_index)
{
u32 trb_slot_id = SLOT_ID_FOR_TRB(slot_id);
u32 trb_ep_index = EP_ID_FOR_TRB(ep_index);
u32 type = TRB_TYPE(TRB_STOP_RING);
return queue_command(xhci, 0, 0, 0,
trb_slot_id | trb_ep_index | type);
}
/* Set Transfer Ring Dequeue Pointer command.
* This should not be used for endpoints that have streams enabled.
*/
static int queue_set_tr_deq(struct xhci_hcd *xhci, int slot_id,
unsigned int ep_index, struct xhci_segment *deq_seg,
union xhci_trb *deq_ptr, u32 cycle_state)
{
dma_addr_t addr;
u32 trb_slot_id = SLOT_ID_FOR_TRB(slot_id);
u32 trb_ep_index = EP_ID_FOR_TRB(ep_index);
u32 type = TRB_TYPE(TRB_SET_DEQ);
addr = xhci_trb_virt_to_dma(deq_seg, deq_ptr);
if (addr == 0) {
xhci_warn(xhci, "WARN Cannot submit Set TR Deq Ptr\n");
xhci_warn(xhci, "WARN deq seg = %p, deq pt = %p\n",
deq_seg, deq_ptr);
return 0;
}
return queue_command(xhci, lower_32_bits(addr) | cycle_state,
upper_32_bits(addr), 0,
trb_slot_id | trb_ep_index | type);
}
int xhci_queue_reset_ep(struct xhci_hcd *xhci, int slot_id,
unsigned int ep_index)
{
u32 trb_slot_id = SLOT_ID_FOR_TRB(slot_id);
u32 trb_ep_index = EP_ID_FOR_TRB(ep_index);
u32 type = TRB_TYPE(TRB_RESET_EP);
return queue_command(xhci, 0, 0, 0, trb_slot_id | trb_ep_index | type);
}
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