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path: root/drivers/usb/musb/musb_host.c
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Diffstat (limited to 'drivers/usb/musb/musb_host.c')
-rw-r--r--drivers/usb/musb/musb_host.c237
1 files changed, 156 insertions, 81 deletions
diff --git a/drivers/usb/musb/musb_host.c b/drivers/usb/musb/musb_host.c
index 99fa6123487..499c431a6d6 100644
--- a/drivers/usb/musb/musb_host.c
+++ b/drivers/usb/musb/musb_host.c
@@ -64,11 +64,8 @@
*
* - DMA (Mentor/OMAP) ...has at least toggle update problems
*
- * - Still no traffic scheduling code to make NAKing for bulk or control
- * transfers unable to starve other requests; or to make efficient use
- * of hardware with periodic transfers. (Note that network drivers
- * commonly post bulk reads that stay pending for a long time; these
- * would make very visible trouble.)
+ * - [23-feb-2009] minimal traffic scheduling to avoid bulk RX packet
+ * starvation ... nothing yet for TX, interrupt, or bulk.
*
* - Not tested with HNP, but some SRP paths seem to behave.
*
@@ -88,11 +85,8 @@
*
* CONTROL transfers all go through ep0. BULK ones go through dedicated IN
* and OUT endpoints ... hardware is dedicated for those "async" queue(s).
- *
* (Yes, bulk _could_ use more of the endpoints than that, and would even
- * benefit from it ... one remote device may easily be NAKing while others
- * need to perform transfers in that same direction. The same thing could
- * be done in software though, assuming dma cooperates.)
+ * benefit from it.)
*
* INTERUPPT and ISOCHRONOUS transfers are scheduled to the other endpoints.
* So far that scheduling is both dumb and optimistic: the endpoint will be
@@ -201,8 +195,9 @@ musb_start_urb(struct musb *musb, int is_in, struct musb_qh *qh)
len = urb->iso_frame_desc[0].length;
break;
default: /* bulk, interrupt */
- buf = urb->transfer_buffer;
- len = urb->transfer_buffer_length;
+ /* actual_length may be nonzero on retry paths */
+ buf = urb->transfer_buffer + urb->actual_length;
+ len = urb->transfer_buffer_length - urb->actual_length;
}
DBG(4, "qh %p urb %p dev%d ep%d%s%s, hw_ep %d, %p/%d\n",
@@ -335,16 +330,11 @@ musb_save_toggle(struct musb_hw_ep *ep, int is_in, struct urb *urb)
static struct musb_qh *
musb_giveback(struct musb_qh *qh, struct urb *urb, int status)
{
- int is_in;
struct musb_hw_ep *ep = qh->hw_ep;
struct musb *musb = ep->musb;
+ int is_in = usb_pipein(urb->pipe);
int ready = qh->is_ready;
- if (ep->is_shared_fifo)
- is_in = 1;
- else
- is_in = usb_pipein(urb->pipe);
-
/* save toggle eagerly, for paranoia */
switch (qh->type) {
case USB_ENDPOINT_XFER_BULK:
@@ -400,7 +390,6 @@ musb_giveback(struct musb_qh *qh, struct urb *urb, int status)
* de-allocated if it's tracked and allocated;
* and where we'd update the schedule tree...
*/
- musb->periodic[ep->epnum] = NULL;
kfree(qh);
qh = NULL;
break;
@@ -432,7 +421,7 @@ musb_advance_schedule(struct musb *musb, struct urb *urb,
else
qh = musb_giveback(qh, urb, urb->status);
- if (qh && qh->is_ready && !list_empty(&qh->hep->urb_list)) {
+ if (qh != NULL && qh->is_ready) {
DBG(4, "... next ep%d %cX urb %p\n",
hw_ep->epnum, is_in ? 'R' : 'T',
next_urb(qh));
@@ -942,8 +931,8 @@ static bool musb_h_ep0_continue(struct musb *musb, u16 len, struct urb *urb)
switch (musb->ep0_stage) {
case MUSB_EP0_IN:
fifo_dest = urb->transfer_buffer + urb->actual_length;
- fifo_count = min(len, ((u16) (urb->transfer_buffer_length
- - urb->actual_length)));
+ fifo_count = min_t(size_t, len, urb->transfer_buffer_length -
+ urb->actual_length);
if (fifo_count < len)
urb->status = -EOVERFLOW;
@@ -976,10 +965,9 @@ static bool musb_h_ep0_continue(struct musb *musb, u16 len, struct urb *urb)
}
/* FALLTHROUGH */
case MUSB_EP0_OUT:
- fifo_count = min(qh->maxpacket, ((u16)
- (urb->transfer_buffer_length
- - urb->actual_length)));
-
+ fifo_count = min_t(size_t, qh->maxpacket,
+ urb->transfer_buffer_length -
+ urb->actual_length);
if (fifo_count) {
fifo_dest = (u8 *) (urb->transfer_buffer
+ urb->actual_length);
@@ -1051,7 +1039,8 @@ irqreturn_t musb_h_ep0_irq(struct musb *musb)
/* NOTE: this code path would be a good place to PAUSE a
* control transfer, if another one is queued, so that
- * ep0 is more likely to stay busy.
+ * ep0 is more likely to stay busy. That's already done
+ * for bulk RX transfers.
*
* if (qh->ring.next != &musb->control), then
* we have a candidate... NAKing is *NOT* an error
@@ -1161,7 +1150,8 @@ void musb_host_tx(struct musb *musb, u8 epnum)
struct urb *urb;
struct musb_hw_ep *hw_ep = musb->endpoints + epnum;
void __iomem *epio = hw_ep->regs;
- struct musb_qh *qh = hw_ep->out_qh;
+ struct musb_qh *qh = hw_ep->is_shared_fifo ? hw_ep->in_qh
+ : hw_ep->out_qh;
u32 status = 0;
void __iomem *mbase = musb->mregs;
struct dma_channel *dma;
@@ -1202,6 +1192,7 @@ void musb_host_tx(struct musb *musb, u8 epnum)
/* NOTE: this code path would be a good place to PAUSE a
* transfer, if there's some other (nonperiodic) tx urb
* that could use this fifo. (dma complicates it...)
+ * That's already done for bulk RX transfers.
*
* if (bulk && qh->ring.next != &musb->out_bulk), then
* we have a candidate... NAKing is *NOT* an error
@@ -1308,7 +1299,8 @@ void musb_host_tx(struct musb *musb, u8 epnum)
* packets before updating TXCSR ... other docs disagree ...
*/
/* PIO: start next packet in this URB */
- wLength = min(qh->maxpacket, (u16) wLength);
+ if (wLength > qh->maxpacket)
+ wLength = qh->maxpacket;
musb_write_fifo(hw_ep, wLength, buf);
qh->segsize = wLength;
@@ -1362,6 +1354,50 @@ finish:
#endif
+/* Schedule next QH from musb->in_bulk and move the current qh to
+ * the end; avoids starvation for other endpoints.
+ */
+static void musb_bulk_rx_nak_timeout(struct musb *musb, struct musb_hw_ep *ep)
+{
+ struct dma_channel *dma;
+ struct urb *urb;
+ void __iomem *mbase = musb->mregs;
+ void __iomem *epio = ep->regs;
+ struct musb_qh *cur_qh, *next_qh;
+ u16 rx_csr;
+
+ musb_ep_select(mbase, ep->epnum);
+ dma = is_dma_capable() ? ep->rx_channel : NULL;
+
+ /* clear nak timeout bit */
+ rx_csr = musb_readw(epio, MUSB_RXCSR);
+ rx_csr |= MUSB_RXCSR_H_WZC_BITS;
+ rx_csr &= ~MUSB_RXCSR_DATAERROR;
+ musb_writew(epio, MUSB_RXCSR, rx_csr);
+
+ cur_qh = first_qh(&musb->in_bulk);
+ if (cur_qh) {
+ urb = next_urb(cur_qh);
+ if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
+ dma->status = MUSB_DMA_STATUS_CORE_ABORT;
+ musb->dma_controller->channel_abort(dma);
+ urb->actual_length += dma->actual_len;
+ dma->actual_len = 0L;
+ }
+ musb_save_toggle(ep, 1, urb);
+
+ /* move cur_qh to end of queue */
+ list_move_tail(&cur_qh->ring, &musb->in_bulk);
+
+ /* get the next qh from musb->in_bulk */
+ next_qh = first_qh(&musb->in_bulk);
+
+ /* set rx_reinit and schedule the next qh */
+ ep->rx_reinit = 1;
+ musb_start_urb(musb, 1, next_qh);
+ }
+}
+
/*
* Service an RX interrupt for the given IN endpoint; docs cover bulk, iso,
* and high-bandwidth IN transfer cases.
@@ -1425,18 +1461,26 @@ void musb_host_rx(struct musb *musb, u8 epnum)
} else if (rx_csr & MUSB_RXCSR_DATAERROR) {
if (USB_ENDPOINT_XFER_ISOC != qh->type) {
- /* NOTE this code path would be a good place to PAUSE a
- * transfer, if there's some other (nonperiodic) rx urb
- * that could use this fifo. (dma complicates it...)
+ DBG(6, "RX end %d NAK timeout\n", epnum);
+
+ /* NOTE: NAKing is *NOT* an error, so we want to
+ * continue. Except ... if there's a request for
+ * another QH, use that instead of starving it.
*
- * if (bulk && qh->ring.next != &musb->in_bulk), then
- * we have a candidate... NAKing is *NOT* an error
+ * Devices like Ethernet and serial adapters keep
+ * reads posted at all times, which will starve
+ * other devices without this logic.
*/
- DBG(6, "RX end %d NAK timeout\n", epnum);
+ if (usb_pipebulk(urb->pipe)
+ && qh->mux == 1
+ && !list_is_singular(&musb->in_bulk)) {
+ musb_bulk_rx_nak_timeout(musb, hw_ep);
+ return;
+ }
musb_ep_select(mbase, epnum);
- musb_writew(epio, MUSB_RXCSR,
- MUSB_RXCSR_H_WZC_BITS
- | MUSB_RXCSR_H_REQPKT);
+ rx_csr |= MUSB_RXCSR_H_WZC_BITS;
+ rx_csr &= ~MUSB_RXCSR_DATAERROR;
+ musb_writew(epio, MUSB_RXCSR, rx_csr);
goto finish;
} else {
@@ -1715,31 +1759,27 @@ static int musb_schedule(
/* else, periodic transfers get muxed to other endpoints */
- /* FIXME this doesn't consider direction, so it can only
- * work for one half of the endpoint hardware, and assumes
- * the previous cases handled all non-shared endpoints...
- */
-
- /* we know this qh hasn't been scheduled, so all we need to do
+ /*
+ * We know this qh hasn't been scheduled, so all we need to do
* is choose which hardware endpoint to put it on ...
*
* REVISIT what we really want here is a regular schedule tree
- * like e.g. OHCI uses, but for now musb->periodic is just an
- * array of the _single_ logical endpoint associated with a
- * given physical one (identity mapping logical->physical).
- *
- * that simplistic approach makes TT scheduling a lot simpler;
- * there is none, and thus none of its complexity...
+ * like e.g. OHCI uses.
*/
best_diff = 4096;
best_end = -1;
- for (epnum = 1; epnum < musb->nr_endpoints; epnum++) {
+ for (epnum = 1, hw_ep = musb->endpoints + 1;
+ epnum < musb->nr_endpoints;
+ epnum++, hw_ep++) {
int diff;
- if (musb->periodic[epnum])
+ if (is_in || hw_ep->is_shared_fifo) {
+ if (hw_ep->in_qh != NULL)
+ continue;
+ } else if (hw_ep->out_qh != NULL)
continue;
- hw_ep = &musb->endpoints[epnum];
+
if (hw_ep == musb->bulk_ep)
continue;
@@ -1760,6 +1800,17 @@ static int musb_schedule(
head = &musb->in_bulk;
else
head = &musb->out_bulk;
+
+ /* Enable bulk RX NAK timeout scheme when bulk requests are
+ * multiplexed. This scheme doen't work in high speed to full
+ * speed scenario as NAK interrupts are not coming from a
+ * full speed device connected to a high speed device.
+ * NAK timeout interval is 8 (128 uframe or 16ms) for HS and
+ * 4 (8 frame or 8ms) for FS device.
+ */
+ if (is_in && qh->dev)
+ qh->intv_reg =
+ (USB_SPEED_HIGH == qh->dev->speed) ? 8 : 4;
goto success;
} else if (best_end < 0) {
return -ENOSPC;
@@ -1768,7 +1819,6 @@ static int musb_schedule(
idle = 1;
qh->mux = 0;
hw_ep = musb->endpoints + best_end;
- musb->periodic[best_end] = qh;
DBG(4, "qh %p periodic slot %d\n", qh, best_end);
success:
if (head) {
@@ -1847,8 +1897,8 @@ static int musb_urb_enqueue(
goto done;
}
- qh->epnum = epd->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;
- qh->type = epd->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK;
+ qh->epnum = usb_endpoint_num(epd);
+ qh->type = usb_endpoint_type(epd);
/* NOTE: urb->dev->devnum is wrong during SET_ADDRESS */
qh->addr_reg = (u8) usb_pipedevice(urb->pipe);
@@ -1867,19 +1917,21 @@ static int musb_urb_enqueue(
}
qh->type_reg = type_reg;
- /* precompute rxinterval/txinterval register */
- interval = min((u8)16, epd->bInterval); /* log encoding */
+ /* Precompute RXINTERVAL/TXINTERVAL register */
switch (qh->type) {
case USB_ENDPOINT_XFER_INT:
- /* fullspeed uses linear encoding */
- if (USB_SPEED_FULL == urb->dev->speed) {
- interval = epd->bInterval;
- if (!interval)
- interval = 1;
+ /*
+ * Full/low speeds use the linear encoding,
+ * high speed uses the logarithmic encoding.
+ */
+ if (urb->dev->speed <= USB_SPEED_FULL) {
+ interval = max_t(u8, epd->bInterval, 1);
+ break;
}
/* FALLTHROUGH */
case USB_ENDPOINT_XFER_ISOC:
- /* iso always uses log encoding */
+ /* ISO always uses logarithmic encoding */
+ interval = min_t(u8, epd->bInterval, 16);
break;
default:
/* REVISIT we actually want to use NAK limits, hinting to the
@@ -1890,13 +1942,11 @@ static int musb_urb_enqueue(
*
* The downside of disabling this is that transfer scheduling
* gets VERY unfair for nonperiodic transfers; a misbehaving
- * peripheral could make that hurt. Or for reads, one that's
- * perfectly normal: network and other drivers keep reads
- * posted at all times, having one pending for a week should
- * be perfectly safe.
+ * peripheral could make that hurt. That's perfectly normal
+ * for reads from network or serial adapters ... so we have
+ * partial NAKlimit support for bulk RX.
*
- * The upside of disabling it is avoidng transfer scheduling
- * code to put this aside for while.
+ * The upside of disabling it is simpler transfer scheduling.
*/
interval = 0;
}
@@ -2037,9 +2087,9 @@ static int musb_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
goto done;
/* Any URB not actively programmed into endpoint hardware can be
- * immediately given back. Such an URB must be at the head of its
+ * immediately given back; that's any URB not at the head of an
* endpoint queue, unless someday we get real DMA queues. And even
- * then, it might not be known to the hardware...
+ * if it's at the head, it might not be known to the hardware...
*
* Otherwise abort current transfer, pending dma, etc.; urb->status
* has already been updated. This is a synchronous abort; it'd be
@@ -2078,6 +2128,15 @@ static int musb_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
qh->is_ready = 0;
__musb_giveback(musb, urb, 0);
qh->is_ready = ready;
+
+ /* If nothing else (usually musb_giveback) is using it
+ * and its URB list has emptied, recycle this qh.
+ */
+ if (ready && list_empty(&qh->hep->urb_list)) {
+ qh->hep->hcpriv = NULL;
+ list_del(&qh->ring);
+ kfree(qh);
+ }
} else
ret = musb_cleanup_urb(urb, qh, urb->pipe & USB_DIR_IN);
done:
@@ -2093,15 +2152,16 @@ musb_h_disable(struct usb_hcd *hcd, struct usb_host_endpoint *hep)
unsigned long flags;
struct musb *musb = hcd_to_musb(hcd);
u8 is_in = epnum & USB_DIR_IN;
- struct musb_qh *qh = hep->hcpriv;
- struct urb *urb, *tmp;
+ struct musb_qh *qh;
+ struct urb *urb;
struct list_head *sched;
- if (!qh)
- return;
-
spin_lock_irqsave(&musb->lock, flags);
+ qh = hep->hcpriv;
+ if (qh == NULL)
+ goto exit;
+
switch (qh->type) {
case USB_ENDPOINT_XFER_CONTROL:
sched = &musb->control;
@@ -2135,13 +2195,28 @@ musb_h_disable(struct usb_hcd *hcd, struct usb_host_endpoint *hep)
/* cleanup */
musb_cleanup_urb(urb, qh, urb->pipe & USB_DIR_IN);
- } else
- urb = NULL;
- /* then just nuke all the others */
- list_for_each_entry_safe_from(urb, tmp, &hep->urb_list, urb_list)
- musb_giveback(qh, urb, -ESHUTDOWN);
+ /* Then nuke all the others ... and advance the
+ * queue on hw_ep (e.g. bulk ring) when we're done.
+ */
+ while (!list_empty(&hep->urb_list)) {
+ urb = next_urb(qh);
+ urb->status = -ESHUTDOWN;
+ musb_advance_schedule(musb, urb, qh->hw_ep, is_in);
+ }
+ } else {
+ /* Just empty the queue; the hardware is busy with
+ * other transfers, and since !qh->is_ready nothing
+ * will activate any of these as it advances.
+ */
+ while (!list_empty(&hep->urb_list))
+ __musb_giveback(musb, next_urb(qh), -ESHUTDOWN);
+ hep->hcpriv = NULL;
+ list_del(&qh->ring);
+ kfree(qh);
+ }
+exit:
spin_unlock_irqrestore(&musb->lock, flags);
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-27 11:41:36 +0000