Commit 30a03849 authored by David Brownell's avatar David Brownell Committed by Greg Kroah-Hartman

[PATCH] ehci, qtd submit and completions

This ought to address a number of the problems with the
recent "dummy td" update as well as some older ones:

    - Slims down the qh_append_tds() to remove two pairs
      of "should be duplicate" logic so that
        * qh_make() only creates and initializes;
        * qh_append_tds() calls it earlier;
        * always appends with dummy, no routine qh updates.

    - Reworked qh_completions() ... simpler, better.
       * two notable FIXMEs gone, and a bug related to
         how they interacted with scatterlist i/o
       * fixed bugs (including one oops) exposed by
         using dummies more.

Passes basic testing:  most 'usbtest' cases, usb2 hub
with keyboard and CF adapter, storage enumeration.
So it seems less troublesome, though it's still not
as happy as I've seen it.

However, "testusb -at12" (running 'write unlink' tests)
still fails for me, and usb-storage gets unhappy when
it decides (why?  and unsuccessfully) to reset high speed
devices.  I'm still chasing those problems, which seem
to come from higher up in the stack.
parent 8725a007
......@@ -58,7 +58,7 @@ static void ehci_hcd_free (struct usb_hcd *hcd)
/* Allocate the key transfer structures from the previously allocated pool */
static void ehci_qtd_init (struct ehci_qtd *qtd, dma_addr_t dma)
static inline void ehci_qtd_init (struct ehci_qtd *qtd, dma_addr_t dma)
{
memset (qtd, 0, sizeof *qtd);
qtd->qtd_dma = dma;
......
......@@ -80,7 +80,7 @@ qtd_fill (struct ehci_qtd *qtd, dma_addr_t buf, size_t len, int token)
/* update halted (but potentially linked) qh */
static void
static inline void
qh_update (struct ehci_hcd *ehci, struct ehci_qh *qh, struct ehci_qtd *qtd)
{
qh->hw_current = 0;
......@@ -94,6 +94,8 @@ qh_update (struct ehci_hcd *ehci, struct ehci_qh *qh, struct ehci_qtd *qtd)
/*-------------------------------------------------------------------------*/
#define IS_SHORT_READ(token) (QTD_LENGTH (token) != 0 && QTD_PID (token) == 1)
static inline void qtd_copy_status (
struct ehci_hcd *ehci,
struct urb *urb,
......@@ -106,7 +108,15 @@ static inline void qtd_copy_status (
urb->actual_length += length - QTD_LENGTH (token);
/* don't modify error codes */
if (unlikely (urb->status == -EINPROGRESS && (token & QTD_STS_HALT))) {
if (unlikely (urb->status != -EINPROGRESS))
return;
/* force cleanup after short read; not always an error */
if (unlikely (IS_SHORT_READ (token)))
urb->status = -EREMOTEIO;
/* serious "can't proceed" faults reported by the hardware */
if (token & QTD_STS_HALT) {
if (token & QTD_STS_BABBLE) {
/* FIXME "must" disable babbling device's port too */
urb->status = -EOVERFLOW;
......@@ -158,13 +168,6 @@ static inline void qtd_copy_status (
}
}
}
/* force cleanup after short read; not necessarily an error */
if (unlikely (urb->status == -EINPROGRESS
&& QTD_LENGTH (token) != 0
&& QTD_PID (token) == 1)) {
urb->status = -EREMOTEIO;
}
}
static void
......@@ -215,26 +218,31 @@ ehci_urb_done (struct ehci_hcd *ehci, struct urb *urb, struct pt_regs *regs)
* Chases up to qh->hw_current. Returns number of completions called,
* indicating how much "real" work we did.
*/
#define HALT_BIT cpu_to_le32(QTD_STS_HALT)
static unsigned
qh_completions (struct ehci_hcd *ehci, struct ehci_qh *qh, struct pt_regs *regs)
{
struct ehci_qtd *qtd, *last;
struct list_head *next, *qtd_list = &qh->qtd_list;
int unlink = 0, stopped = 0;
struct ehci_qtd *last = 0;
struct list_head *entry, *tmp;
int stopped = 0;
unsigned count = 0;
if (unlikely (list_empty (&qh->qtd_list)))
return count;
/* scan QTDs till end of list, or we reach an active one */
for (qtd = list_entry (qtd_list->next, struct ehci_qtd, qtd_list),
last = 0, next = 0;
next != qtd_list;
last = qtd, qtd = list_entry (next,
struct ehci_qtd, qtd_list)) {
struct urb *urb = qtd->urb;
/* remove de-activated QTDs from front of queue.
* after faults (including short reads), cleanup this urb
* then let the queue advance.
* if queue is stopped, handles unlinks.
*/
list_for_each_safe (entry, tmp, &qh->qtd_list) {
struct ehci_qtd *qtd;
struct urb *urb;
u32 token = 0;
qtd = list_entry (entry, struct ehci_qtd, qtd_list);
urb = qtd->urb;
/* clean up any state from previous QTD ...*/
if (last) {
if (likely (last->urb != urb)) {
......@@ -244,74 +252,59 @@ qh_completions (struct ehci_hcd *ehci, struct ehci_qh *qh, struct pt_regs *regs)
ehci_qtd_free (ehci, last);
last = 0;
}
next = qtd->qtd_list.next;
/* QTDs at tail may be active if QH+HC are running,
* or when unlinking some urbs queued to this QH
*/
/* hardware copies qtd out of qh overlay */
rmb ();
token = le32_to_cpu (qtd->hw_token);
stopped = stopped
|| (qh->qh_state == QH_STATE_IDLE)
|| (__constant_cpu_to_le32 (QTD_STS_HALT)
& qh->hw_token) != 0
|| (ehci->hcd.state == USB_STATE_HALT)
|| (qh->hw_current == ehci->async->hw_alt_next);
// FIXME Remove the automagic unlink mode.
// Drivers can now clean up safely; it's their job.
//
// FIXME Removing it should fix the short read scenarios
// with "huge" urb data (more than one 16+KByte td) with
// the short read someplace other than the last data TD.
// Except the control case: 'retrigger' status ACKs.
/* fault: unlink the rest, since this qtd saw an error? */
if (unlikely ((token & QTD_STS_HALT) != 0)) {
unlink = 1;
/* status copied below */
/* QH halts only because of fault (above) or unlink (here). */
} else if (unlikely (stopped != 0)) {
/* unlinking everything because of HC shutdown? */
if (ehci->hcd.state == USB_STATE_HALT) {
unlink = 1;
/* explicit unlink, maybe starting here? */
} else if (qh->qh_state == QH_STATE_IDLE
&& (urb->status == -ECONNRESET
|| urb->status == -ESHUTDOWN
|| urb->status == -ENOENT)) {
unlink = 1;
/* QH halted to unlink urbs _after_ this? */
} else if (!unlink && (token & QTD_STS_ACTIVE) != 0) {
qtd = 0;
continue;
}
|| (HALT_BIT & qh->hw_token) != 0
|| (ehci->hcd.state == USB_STATE_HALT);
/* unlink the rest? once we start unlinking, after
* a fault or explicit unlink, we unlink all later
* urbs. usb spec requires that for faults...
*/
if (unlink && urb->status == -EINPROGRESS)
urb->status = -ECONNRESET;
/* always clean up qtds the hc de-activated */
if ((token & QTD_STS_ACTIVE) == 0) {
/* Else QH is active, so we must not modify QTDs
* that HC may be working on. No more qtds to check.
*/
} else if (unlikely ((token & QTD_STS_ACTIVE) != 0)) {
next = qtd_list;
qtd = 0;
continue;
}
/* magic dummy for short reads; won't advance */
if (IS_SHORT_READ (token)
&& ehci->async->hw_alt_next
== qh->hw_current)
goto halt;
/* stop scanning when we reach qtds the hc is using */
} else if (likely (!stopped)) {
last = 0;
break;
} else {
/* ignore active qtds unless some previous qtd
* for the urb faulted (including short read) or
* its urb was canceled. we may patch qh or qtds.
*/
if ((token & QTD_STS_ACTIVE)
&& urb->status == -EINPROGRESS) {
last = 0;
continue;
}
if ((HALT_BIT & qh->hw_token) == 0) {
halt:
qh->hw_token |= HALT_BIT;
wmb ();
stopped = 1;
}
}
/* remove it from the queue */
spin_lock (&urb->lock);
qtd_copy_status (ehci, urb, qtd->length, token);
spin_unlock (&urb->lock);
if (stopped && qtd->qtd_list.prev != &qh->qtd_list) {
last = list_entry (qtd->qtd_list.prev,
struct ehci_qtd, qtd_list);
last->hw_next = qtd->hw_next;
}
list_del (&qtd->qtd_list);
last = qtd;
}
/* last urb's completion might still need calling */
......@@ -321,14 +314,18 @@ qh_completions (struct ehci_hcd *ehci, struct ehci_qh *qh, struct pt_regs *regs)
ehci_qtd_free (ehci, last);
}
/* reactivate queue after error and driver's cleanup */
if (unlikely (stopped && !list_empty (&qh->qtd_list))) {
qh_update (ehci, qh, list_entry (qh->qtd_list.next,
struct ehci_qtd, qtd_list));
/* update qh after fault cleanup */
if (unlikely ((HALT_BIT & qh->hw_token) != 0)) {
qh_update (ehci, qh,
list_empty (&qh->qtd_list)
? qh->dummy
: list_entry (qh->qtd_list.next,
struct ehci_qtd, qtd_list));
}
return count;
}
#undef HALT_BIT
/*-------------------------------------------------------------------------*/
......@@ -536,10 +533,9 @@ clear_toggle (struct usb_device *udev, int ep, int is_out, struct ehci_qh *qh)
* there are additional complications: c-mask, maybe FSTNs.
*/
static struct ehci_qh *
ehci_qh_make (
qh_make (
struct ehci_hcd *ehci,
struct urb *urb,
struct list_head *qtd_list,
int flags
) {
struct ehci_qh *qh = ehci_qh_alloc (ehci, flags);
......@@ -649,27 +645,13 @@ ehci_qh_make (
/* NOTE: if (PIPE_INTERRUPT) { scheduler sets s-mask } */
/* init as halted, toggle clear, advance to dummy */
qh->qh_state = QH_STATE_IDLE;
qh->hw_info1 = cpu_to_le32 (info1);
qh->hw_info2 = cpu_to_le32 (info2);
/* initialize sw and hw queues with these qtds */
if (!list_empty (qtd_list)) {
struct ehci_qtd *qtd;
/* hc's list view ends with dummy td; we might update it */
qtd = list_entry (qtd_list->prev, struct ehci_qtd, qtd_list);
qtd->hw_next = QTD_NEXT (qh->dummy->qtd_dma);
list_splice (qtd_list, &qh->qtd_list);
qtd = list_entry (qtd_list->next, struct ehci_qtd, qtd_list);
qh_update (ehci, qh, qtd);
} else {
qh->hw_qtd_next = qh->hw_alt_next = EHCI_LIST_END;
}
/* initialize data toggle state */
clear_toggle (urb->dev, usb_pipeendpoint (urb->pipe), !is_input, qh);
qh_update (ehci, qh, qh->dummy);
qh->hw_token = cpu_to_le32 (QTD_STS_HALT);
usb_settoggle (urb->dev, usb_pipeendpoint (urb->pipe), !is_input, 1);
return qh;
}
#undef hb_mult
......@@ -736,6 +718,11 @@ static struct ehci_qh *qh_append_tds (
struct ehci_qh *qh = 0;
qh = (struct ehci_qh *) *ptr;
if (unlikely (qh == 0)) {
/* can't sleep here, we have ehci->lock... */
qh = qh_make (ehci, urb, SLAB_ATOMIC);
*ptr = qh;
}
if (likely (qh != 0)) {
struct ehci_qtd *qtd;
......@@ -766,8 +753,34 @@ static struct ehci_qh *qh_append_tds (
}
}
/* append to tds already queued to this qh? */
if (unlikely (!list_empty (&qh->qtd_list) && qtd)) {
/* FIXME: changing config or interface setting is not
* supported yet. preferred fix is for usbcore to tell
* us to clear out each endpoint's state, but...
*/
/* usb_clear_halt() means qh data toggle gets reset */
if (unlikely (!usb_gettoggle (urb->dev,
(epnum & 0x0f), !(epnum & 0x10)))
&& !usb_pipecontrol (urb->pipe)) {
/* "never happens": drivers do stall cleanup right */
if (qh->qh_state != QH_STATE_IDLE
&& (cpu_to_le32 (QTD_STS_HALT)
& qh->hw_token) == 0)
ehci_warn (ehci, "clear toggle dev%d "
"ep%d%s: not idle\n",
usb_pipedevice (urb->pipe),
epnum & 0x0f,
usb_pipein (urb->pipe)
? "in" : "out");
/* else we know this overlay write is safe */
clear_toggle (urb->dev,
epnum & 0x0f, !(epnum & 0x10), qh);
}
/* just one way to queue requests: swap with the dummy qtd.
* only hc or qh_completions() usually modify the overlay.
*/
if (likely (qtd != 0)) {
struct ehci_qtd *dummy;
dma_addr_t dma;
u32 token;
......@@ -785,8 +798,10 @@ static struct ehci_qh *qh_append_tds (
dma = dummy->qtd_dma;
*dummy = *qtd;
dummy->qtd_dma = dma;
list_del (&qtd->qtd_list);
list_add (&dummy->qtd_list, qtd_list);
__list_splice (qtd_list, qh->qtd_list.prev);
ehci_qtd_init (qtd, qtd->qtd_dma);
qtd->hw_alt_next = ehci->async->hw_alt_next;
......@@ -802,36 +817,9 @@ static struct ehci_qh *qh_append_tds (
wmb ();
dummy->hw_token = token;
/* no URB queued */
} else {
/* usb_clear_halt() means qh data toggle gets reset */
if (unlikely (!usb_gettoggle (urb->dev,
(epnum & 0x0f),
!(epnum & 0x10)))) {
clear_toggle (urb->dev,
epnum & 0x0f, !(epnum & 0x10), qh);
}
/* make sure hc sees current dummy at the end */
if (qtd) {
struct ehci_qtd *last_qtd;
last_qtd = list_entry (qtd_list->prev,
struct ehci_qtd, qtd_list);
last_qtd->hw_next = QTD_NEXT (
qh->dummy->qtd_dma);
qh_update (ehci, qh, qtd);
}
urb->hcpriv = qh_get (qh);
}
list_splice (qtd_list, qh->qtd_list.prev);
} else {
/* can't sleep here, we have ehci->lock... */
qh = ehci_qh_make (ehci, urb, qtd_list, SLAB_ATOMIC);
*ptr = qh;
}
if (qh)
urb->hcpriv = qh_get (qh);
return qh;
}
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment