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path: root/drivers/usb/host/xhci-ring.c
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2010-08-23USB: xHCI: update ring dequeue pointer when process missed tdsAndiry Xu
This patch fixes a isoc transfer bug reported by Sander Eikelenboom. When ep->skip is set, endpoint ring dequeue pointer should be updated when processed every missed td. Although ring dequeue pointer will also be updated when ep->skip is clear, leave it intact during missed tds processing may cause two issues: 1). If the very next valid transfer following missed tds is a short transfer, its actual_length will be miscalculated; 2). If there are too many missed tds during transfer, new inserted tds may found the transfer ring full and urb enqueue fails. Reported-by: Sander Eikelenboom <linux@eikelenboom.it> Tested-by: Sander Eikelenboom <linux@eikelenboom.it> Signed-off-by: Andiry Xu <andiry.xu@amd.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-23USB: xhci: Remove buggy assignment in next_trb()John Youn
The code to increment the TRB pointer has a slight ambiguity that could lead to a bug on different compilers. The ANSI C specification does not specify the precedence of the assignment operator over the postfix operator. gcc 4.4 produced the correct code (increment the pointer and assign the value), but a MIPS compiler that one of John's clients used assigned the old (unincremented) value. Remove the unnecessary assignment to make all compilers produce the correct assembly. Signed-off-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-10USB: xhci: Don't flush doorbell writes.Sarah Sharp
To tell the host controller that there are transfers on the endpoint rings, we need to ring the endpoint doorbell. This is a PCI MMIO write, which can be delayed until another register read is queued. The previous code would flush the doorbell write by reading the doorbell register after the write. This may take time, and it's not necessary to force the host controller to know about the transfers right away. Don't flush the doorbell register writes. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-10USB: xhci: Reduce reads and writes of interrupter registers.Sarah Sharp
The interrupter register set includes a register that says whether interrupts are pending for each event ring (the IP bit). Each MSI-X vector will get its own interrupter set with separate IP bits. The status register includes an "Event Interrupt (EINT)" bit that is set when an IP bit is set in any of the interrupters. When PCI interrupts are used, the EINT bit exactly mirrors the IP bit in the single interrupter set, and it is a waste of time to check both registers when trying to figure out if the xHC interrupted or another device on the shared IRQ line interrupted. Only check the IP bit to reduce register reads. The IP bit is automatically cleared by the xHC when MSI or MSI-X is enabled. It doesn't make sense to read that register to check for shared interrupts (since MSI and MSI-X aren't shared). It also doesn't make sense to write to that register to clear the IP bit, since it is cleared by the hardware. We can tell whether MSI or MSI-X is enabled by looking at the irq number in hcd->irq. If it's -1, we know MSI or MSI-X is enabled. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-10USB: xhci: Make xhci_set_hc_event_deq() static.Sarah Sharp
Now that the event handler functions no longer use xhci_set_hc_event_deq() to update the event ring dequeue pointer, that function is not used by anything in xhci-ring.c. Move that function into xhci-mem.c and make it static. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-10USB: xhci: Minimize HW event ring dequeue pointer writes.Sarah Sharp
The xHCI specification suggests that writing the hardware event ring dequeue pointer register too often can be an expensive operation for the xHCI hardware to manage. It suggests minimizing the number of writes to that register. Originally, the driver wrote the event ring dequeue pointer after each event was processed. Depending on how the event ring moderation register is set up and how fast the transfers are completing, there may be several events processed for each interrupt. This patch makes the hardware event ring dequeue pointer be written only once per interrupt. Make the transfer event handler and port status event handler only write the software event ring dequeue pointer. Move the updating of the hardware event ring dequeue pointer into the interrupt function. Move the contents of xhci_set_hc_event_deq() into the interrupt handler. The interrupt handler must clear the event handler busy flag, so it might as well also write the dequeue pointer to the same register. This eliminates two 32-bit PCI reads and two 32-bit PCI writes. Reported-by: Andiry Xu <andiry.xu@amd.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-10USB: xhci: Make xhci_handle_event() static.Sarah Sharp
xhci_handle_event() is now only called from within xhci-ring.c, so make it static. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-10USB: xhci: Remove unnecessary reads of IRQ_PENDING register.Sarah Sharp
Remove a duplicate register read of the interrupt pending register from xhci_irq(). Also, remove waiting on the posted write of that register. The host will see it eventually. It will probably read the register itself before deciding whether to interrupt the system again, forcing the posted write to complete. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-10USB: xhci: Performance - move xhci_work() into xhci_irq()Sarah Sharp
When we move xhci_work() into xhci_irq(), we don't need to read the operational register status field twice. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-10USB: xhci: Performance - move interrupt handlers into xhci-ring.cSarah Sharp
Most of the work for interrupt handling is done in xhci-ring.c, so it makes sense to move the functions that are first called when an interrupt happens (xhci_irq() or xhci_msi_irq()) into xhci-ring.c, so that the compiler can better optimize them. Shorten some lines to make it pass checkpatch. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-10USB: xhci: Performance - move functions that find ep ring.Sarah Sharp
I've been using perf to measure the top symbols while transferring 1GB of data on a USB 3.0 drive with dd. This is using the raw disk with /dev/sdb, with a block size of 1K. During performance testing, the top symbol was xhci_triad_to_transfer_ring(), a function that should return immediately if streams are not enabled for an endpoint. It turned out that the functions to find the endpoint ring was defined in xhci-mem.c and used in xhci-ring.c and xhci-hcd.c. I moved a copy of xhci_triad_to_transfer_ring() and xhci_urb_to_transfer_ring() into xhci-ring.c and declared them static. I also made a static version of xhci_urb_to_transfer_ring() in xhci.c. This improved throughput on a 1GB read of the raw disk with dd from 186MB/s to 195MB/s, and perf reported sampling the xhci_triad_to_transfer_ring() 0.06% of the time, rather than 9.26% of the time. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-10USB: xHCI: Isochronous transfer implementationAndiry Xu
This patch implements isochronous urb enqueue and interrupt handler part. When an isochronous urb is passed to xHCI driver, first check the transfer ring to guarantee there is enough room for the whole urb. Then update the start_frame and interval field of the urb. Always assume URB_ISO_ASAP is set, and never use urb->start_frame as input. The number of isoc TDs is equal to urb->number_of_packets. One isoc TD is consumed every Interval. Each isoc TD consists of an Isoch TRB chained to zero or more Normal TRBs. Call prepare_transfer for each TD to do initialization; then calculate the number of TRBs needed for each TD. If the data required by an isoc TD is physically contiguous (not crosses a page boundary), then only one isoc TRB is needed; otherwise one or more additional normal TRB shall be chained to the isoc TRB by the host. Set TRB_IOC to the last TRB of each isoc TD. Do not ring endpoint doorbell to start xHC procession until all the TDs are inserted to the endpoint transer ring. In irq handler, update urb status and actual_length, increase urb_priv->td_cnt. When all the TDs are completed(td_cnt is equal to urb_priv->length), giveback the urb to usbcore. Signed-off-by: Andiry Xu <andiry.xu@amd.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-10USB: xHCI: Introduce urb_priv structureAndiry Xu
Add urb_priv data structure to xHCI driver. This structure allows multiple xhci TDs to be linked to one urb, which is essential for isochronous transfer. For non-isochronous urb, only one TD is needed for one urb; for isochronous urb, the TD number for the urb is equal to urb->number_of_packets. The length field of urb_priv indicates the number of TDs in the urb. The td_cnt field indicates the number of TDs already processed by xHC. When td_cnt matches length, the urb can be given back to usbcore. When an urb is dequeued or cancelled, add all the unprocessed TDs to the endpoint's cancelled_td_list. When process a cancelled TD, increase td_cnt field. When td_cnt equals urb_priv->length, giveback the cancelled urb. Signed-off-by: Andiry Xu <andiry.xu@amd.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-10USB: xHCI: Missed Service Error Event processAndiry Xu
This patch adds mechanism to process Missed Service Error Event. Sometimes the xHC is unable to process the isoc TDs in time, it will generate Missed Service Error Event. In this case some TDs on the ring are not processed and missed. When encounter a Missed Servce Error Event, set the skip flag of the ep, and process the missed TDs until reach the next processed TD, then clear the skip flag. Signed-off-by: Andiry Xu <andiry.xu@amd.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-10USB: xHCI: adds new cases to trb_comp_code switchAndiry Xu
This patch adds new cases to trb_comp_code switch, and moves the switch judgment ahead of fetching td. Signed-off-by: Andiry Xu <andiry.xu@amd.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-10USB: xHCI: remove redundant print messagesAndiry Xu
Remove redundant print messages in the interrupt context. Signed-off-by: Andiry Xu <andiry.xu@amd.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-10USB xHCI: handle_tx_event() refactor: process_bulk_intr_tdAndiry Xu
This patch moves the bulk and interrupt td processing part in handle_tx_event() into a separate function process_bulk_intr_td(). Signed-off-by: Andiry Xu <andiry.xu@amd.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-10USB: xHCI: handle_tx_event() refactor: process_ctrl_tdAndiry Xu
This patch moves the ctrl td processing part in handle_tx_event() into a separate function process_ctrl_td(). Signed-off-by: Andiry Xu <andiry.xu@amd.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-10USB: xHCI: handle_tx_event() refactor: finish_tdAndiry Xu
This patch moves the td universal processing part in handle_tx_event() into a separate function finish_td(). if finish_td() returns 1, it indicates the urb can be given back. Signed-off-by: Andiry Xu <andiry.xu@amd.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-07-26USB: xHCI: Fix another bug in link TRB activation change.Sarah Sharp
Commit 6c12db90f19727c76990e7f4801c67a148b30111 also seems to have introduced a bug that is triggered when the command ring is about to wrap. The inc_enq() function will not have moved the enqueue pointer past the link TRB. It is supposed to be moved past the link TRB in prepare_ring(), which should be called before a TD is enqueued. However, the queue_command() function never calls the prepare_ring() function because prepare_ring() is only supposed to be used for endpoint rings. That means the enqueue pointer will not be moved past the link TRB, and will get overwritten. The fix is to make queue_command() call prepare_ring() with a fake endpoint status (set to running). Then the enqueue pointer will get moved past the link TRB. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-06-30USB: xHCI: Fix bug in link TRB activation change.Sarah Sharp
Commit 6c12db90f19727c76990e7f4801c67a148b30111 introduced a bug for control transfers. The patch was supposed to change when the link TRBs at the end of each ring segment were given to the hardware. If a transfer descriptor (TD) ended just before the link TRB, the code wouldn't give back the link TRB to the hardware; instead it would be given back in prepare_ring() just before the next TD was enqueued at the top of the ring. Unfortunately, the code relied on checking the chain bit of the TRB to determine whether the TD ended just before the link TRB. It assumed that the ring enqueuing code would call prepare_ring() before enqueuing the next TD. However, control transfers are made of multiple TDs, and prepare_ring() is only called once before enqueuing two or three TDs. If the first or second TD of the control transfer ended just before the link TRB, then the code in inc_enq() would not move the enqueue pointer past the link TRB, and the link TRB would get overwritten. This would cause the xHCI driver to start writing to memory past the ring segment, and eventually the system would crash or hang. The fix is to add a flag to inc_enq() that says whether the caller will enqueue more TDs before calling prepare_ring(). If the chain bit is cleared (meaning this is the last TRB in a TD), and the caller will not enqueue more TDs, then we defer giving back the link TRB. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-06-04USB: xhci: Print NEC firmware version.Sarah Sharp
The NEC xHCI host controller firmware version can be found by putting a vendor-specific command on the command ring and extracting the BCD encoded-version out of the vendor-specific event TRB. The firmware version debug line in dmesg will look like: xhci_hcd 0000:05:00.0: NEC firmware version 30.21 (NEC merged with Renesas Technologies and became Renesas Electronics on April 1, 2010. I have their OK to merge this vendor-specific code.) Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Cc: Satoshi Otani <satoshi.otani.xm@renesas.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-20USB: xhci: fix compiler warning.Greg Kroah-Hartman
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-20USB: xHCI: Fix wrong usage of macro TRB_TYPEAndiry Xu
Macro TRB_TYPE is misused in some places. Fix the wrong usage. Signed-off-by: Andiry Xu <andiry.xu@amd.com> Cc: stable <stable@kernel.org> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-20USB: xhci: Transfer ring link TRB activation change.John Youn
Change transfer ring behavior to not follow/activate link TRBs until active TRBs are queued after it. This change affects the behavior when a TD ends just before a link TRB. Signed-off-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-20USB: xhci: Set stream ID to 0 after cleaning up stalls.Sarah Sharp
After using state stored in xhci_virt_ep to clean up a stalled endpoint, be sure to set the stalled stream ID back to 0. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-20USB: Change the scatterlist type in struct urbMatthew Wilcox
Change the type of the URB's 'sg' pointer from a usb_sg_request to a scatterlist. This allows drivers to submit scatter-gather lists without using the usb_sg_wait() interface. It has the added benefit of removing the typecasts that were added as part of patch as1368 (and slightly decreasing the number of pointer dereferences). Signed-off-by: Matthew Wilcox <willy@linux.intel.com> Reviewed-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-20USB: clean up some host controller sparse warningsRandy Dunlap
Fix usb sparse warnings: drivers/usb/host/isp1362-hcd.c:2220:50: warning: Using plain integer as NULL pointer drivers/usb/host/xhci-mem.c:43:24: warning: Using plain integer as NULL pointer drivers/usb/host/xhci-mem.c:49:24: warning: Using plain integer as NULL pointer drivers/usb/host/xhci-mem.c:161:24: warning: Using plain integer as NULL pointer drivers/usb/host/xhci-mem.c:198:16: warning: Using plain integer as NULL pointer drivers/usb/host/xhci-mem.c:319:31: warning: Using plain integer as NULL pointer drivers/usb/host/xhci-mem.c:1231:33: warning: Using plain integer as NULL pointer drivers/usb/host/xhci-pci.c:177:23: warning: non-ANSI function declaration of function 'xhci_register_pci' drivers/usb/host/xhci-pci.c:182:26: warning: non-ANSI function declaration of function 'xhci_unregister_pci' drivers/usb/host/xhci-ring.c:342:32: warning: Using plain integer as NULL pointer drivers/usb/host/xhci-ring.c:525:34: warning: Using plain integer as NULL pointer drivers/usb/host/xhci-ring.c:1009:32: warning: Using plain integer as NULL pointer drivers/usb/host/xhci-ring.c:1031:32: warning: Using plain integer as NULL pointer drivers/usb/host/xhci-ring.c:1041:16: warning: Using plain integer as NULL pointer drivers/usb/host/xhci-ring.c:1096:30: warning: Using plain integer as NULL pointer drivers/usb/host/xhci-ring.c:1100:27: warning: Using plain integer as NULL pointer drivers/usb/host/xhci-mem.c:224:27: warning: symbol 'xhci_alloc_container_ctx' was not declared. Should it be static? drivers/usb/host/xhci-mem.c:242:6: warning: symbol 'xhci_free_container_ctx' was not declared. Should it be static? Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Lothar Wassmann <LW@KARO-electronics.de> Signed-off By: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-20USB: xhci: Correct assumptions about number of rings per endpoint.Sarah Sharp
Much of the xHCI driver code assumes that endpoints only have one ring. Now an endpoint can have one ring per enabled stream ID, so correct that assumption. Use functions that translate the stream_id field in the URB or the DMA address of a TRB into the correct stream ring. Correct the polling loop to print out all enabled stream rings. Make the URB cancellation routine find the correct stream ring if the URB has stream_id set. Make sure the URB enqueueing routine does the same. Also correct the code that handles stalled/halted endpoints. Check that commands and registers that can take stream IDs handle them properly. That includes ringing an endpoint doorbell, resetting a stalled/halted endpoint, and setting a transfer ring dequeue pointer (since that command can set the dequeue pointer in a stream context or an endpoint context). Correct the transfer event handler to translate a TRB DMA address into the stream ring it was enqueued to. Make the code to allocate and prepare TD structures adds the TD to the right td_list for the stream ring. Make sure the code to give the first TRB in a TD to the hardware manipulates the correct stream ring. When an endpoint stalls, store the stream ID of the stream ring that stalled in the xhci_virt_ep structure. Use that instead of the stream ID in the URB, since an URB may be re-used after it is given back after a non-control endpoint stall. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-20USB: xhci: Add memory allocation for USB3 bulk streams.Sarah Sharp
Add support for allocating streams for USB 3.0 bulk endpoints. See Documentation/usb/bulk-streams.txt for more information about how and why you would use streams. When an endpoint has streams enabled, instead of having one ring where all transfers are enqueued to the hardware, it has several rings. The ring dequeue pointer in the endpoint context is changed to point to a "Stream Context Array". This is basically an array of pointers to transfer rings, one for each stream ID that the driver wants to use. The Stream Context Array size must be a power of two, and host controllers can place a limit on the size of the array (4 to 2^16 entries). These two facts make calculating the size of the Stream Context Array and the number of entries actually used by the driver a bit tricky. Besides the Stream Context Array and rings for all the stream IDs, we need one more data structure. The xHCI hardware will not tell us which stream ID a transfer event was for, but it will give us the slot ID, endpoint index, and physical address for the TRB that caused the event. For every endpoint on a device, add a radix tree to map physical TRB addresses to virtual segments within a stream ring. Keep track of whether an endpoint is transitioning to using streams, and don't enqueue any URBs while that's taking place. Refuse to transition an endpoint to streams if there are already URBs enqueued for that endpoint. We need to make sure that freeing streams does not fail, since a driver's disconnect() function may attempt to do this, and it cannot fail. Pre-allocate the command structure used to issue the Configure Endpoint command, and reserve space on the command ring for each stream endpoint. This may be a bit overkill, but it is permissible for the driver to allocate all streams in one call and free them in multiple calls. (It is not advised, however, since it is a waste of resources and time.) Even with the memory and ring room pre-allocated, freeing streams can still fail because the xHC rejects the configure endpoint command. It is valid (by the xHCI 0.96 spec) to return a "Bandwidth Error" or a "Resource Error" for a configure endpoint command. We should never see a Bandwidth Error, since bulk endpoints do not effect the reserved bandwidth. The host controller can still return a Resource Error, but it's improbable since the xHC would be going from a more resource-intensive configuration (streams) to a less resource-intensive configuration (no streams). If the xHC returns a Resource Error, the endpoint will be stuck with streams and will be unusable for drivers. It's an unavoidable consequence of broken host controller hardware. Includes bug fixes from the original patch, contributed by John Youn <John.Youn@synopsys.com> and Andy Green <AGreen@PLXTech.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-20USB: fix usbmon and DMA mapping for scatter-gather URBsAlan Stern
This patch (as1368) fixes a rather obscure bug in usbmon: When tracing URBs sent by the scatter-gather library, it accesses the data buffers while they are still mapped for DMA. The solution is to move the mapping and unmapping out of the s-g library and into the usual place in hcd.c. This requires the addition of new URB flag bits to describe the kind of mapping needed, since we have to call dma_map_sg() if the HCD supports native scatter-gather operation and dma_map_page() if it doesn't. The nice thing about having the new flags is that they simplify the testing for unmapping. The patch removes the only caller of usb_buffer_[un]map_sg(), so those functions are #if'ed out. A later patch will remove them entirely. As a result of this change, urb->sg will be set in situations where it wasn't set previously. Hence the xhci and whci drivers are adjusted to test urb->num_sgs instead, which retains its original meaning and is nonzero only when the HCD has to handle a scatterlist. Finally, even when a submission error occurs we don't want to hand URBs to usbmon before they are unmapped. The submission path is rearranged so that map_urb_for_dma() is called only for non-root-hub URBs and unmap_urb_for_dma() is called immediately after a submission error. This simplifies the error handling. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> CC: <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-20USB: xhci: Fix check for room on the ring.Sarah Sharp
The length of the scatter gather list a driver can enqueue is limited by the bus' sg_tablesize to 62 entries. Each entry will be described by at least one transfer request block (TRB). If the entry's buffer crosses a 64KB boundary, then that entry will have to be described by two or more TRBs. So even if the USB device driver respects sg_tablesize, the whole scatter list may take more than 62 TRBs to describe, and won't fit on the ring. Don't assume that an empty ring means there is enough room on the transfer ring. The old code would unconditionally queue this too-large transfer, and over write the beginning of the transfer. This would mean the cycle bit was unchanged in those overwritten transfers, causing the hardware to think it didn't own the TRBs, and the host would seem to hang. Now drivers may see submit_urb() fail with -ENOMEM if the transfers are too big to fit on the ring. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-20USB: xhci: Fix issue with set interface after stall.Sarah Sharp
When the USB core installs a new interface, it unconditionally clears the halts on all the endpoints on the new interface. Usually the xHCI host needs to know when an endpoint is reset, so it can change its internal endpoint state. In this case, it doesn't care, because the endpoints were never halted in the first place. To avoid issuing a redundant Reset Endpoint command, the xHCI driver looks at xhci_virt_ep->stopped_td to determine if the endpoint was actually halted. However, the functions that handle the stall never set that variable to NULL after it dealt with the stall. So if an endpoint stalled and a Reset Endpoint command completed, and then the class driver tried to install a new alternate setting, the xHCI driver would access the old xhci_virt_ep->stopped_td pointer. A similar problem occurs if the endpoint has been stopped to cancel a transfer. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-02USB: xhci: Notify the xHC when a device is reset.Sarah Sharp
When a USB device is reset, the xHCI hardware must know, in order to match the device state and disable all endpoints except control endpoint 0. Issue a Reset Device command after a USB device is successfully reset. Wait on the command to finish, and then cache or free the disabled endpoint rings. There are four different USB device states that the xHCI hardware tracks: - disabled/enabled - device connection has just been detected, - default - the device has been reset and has an address of 0, - addressed - the device has a non-zero address but no configuration has been set, - configured - a set configuration succeeded. The USB core may issue a port reset when a device is in any state, but the Reset Device command will fail for a 0.96 xHC if the device is not in the addressed or configured state. Don't consider this failure as an error, but don't free any endpoint rings if this command fails. A storage driver may request that the USB device be reset during error handling, so use GPF_NOIO instead of GPF_KERNEL while allocating memory for the Reset Device command. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-02USB: xhci: Refactor test for vendor-specific completion codes.Sarah Sharp
All commands that can be issued to the xHCI hardware can come back with vendor-specific "informational" completion codes. These are to be treated like a successful completion code. Refactor out the code to test for the range of these codes and print debugging messages. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-12-11USB: xhci: Fix command completion after a drop endpoint.Sarah Sharp
The xHCI driver issues a Configure Endpoint command for two reasons: - a new configuration or alternate interface setting is selected - a quirky Fresco Logic prototype requires the command after a Reset Endpoint command. The xHCI driver only waits on the command in the first case. When a configure endpoint command completes, the driver needs to know why the command was generated. When the driver only supported selecting an initial configuration, the check was simple. Unfortunately that check doesn't work now that the driver supports alternate interfaces. If an endpoint must be dropped (because it's not in the new alternate setting) and no new endpoints are added, the math involving xhci_last_valid_endpoint() will assign -1 to an unsigned integer and cause an out-of-bounds array access. Move the check for the quirky hardware sooner and avoid the bad array access. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-12-11USB: xhci: Handle errors that cause endpoint halts.Sarah Sharp
The xHCI 0.95 and 0.96 specification defines several transfer buffer request completion codes that indicate a USB transaction error occurred. When a stall, babble, transaction, or split transaction error completion code is set, the xHCI has halted that endpoint ring. Software must issue a Reset Endpoint command and a Set Transfer Ring Dequeue Pointer command to clean up the halted ring. The USB device driver is supposed to call into usb_reset_endpoint() when an endpoint stalls. That calls into the xHCI driver to issue the proper commands. However, drivers don't call that function for the other errors that cause the xHC to halt the endpoint ring. If a babble, transaction, or split transaction error occurs, check if the endpoint context reports a halted condition, and clean up the endpoint ring if it does. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-12-11USB: xhci: Return success for vendor-specific info codes.Sarah Sharp
An xHCI host controller manufacturer can choose to implement several vendor-specific informational completion codes. These are all to be treated like a successful transfer completion. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-12-11USB: xhci: Return -EPROTO on a split transaction error.Sarah Sharp
When the xHCI hardware says a transfer completed with a split transaction error, set the URB status to -EPROTO. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-12-11USB: xhci: Set transfer descriptor size field correctly.Sarah Sharp
The transfer descriptor (TD) is a series of transfer request buffers (TRBs) that describe the buffer pointer, length, and other characteristics. The xHCI controllers want to know an estimate of how long the TD is, for caching reasons. In each TRB, there is a "TD size" field that provides a rough estimate of the remaining buffers to be transmitted, including the buffer pointed to by that TRB. The TD size is 5 bits long, and contains the remaining size in bytes, right shifted by 10 bits. So a remaining TD size less than 1024 would get a zero in the TD size field, and a remaining size greater than 32767 would get 31 in the field. This patches fixes a bug in the TD_REMAINDER macro that is triggered when the URB has a scatter gather list with a size bigger than 32767 bytes. Not all host controllers pay attention to the TD size field, so the bug will not appear on all USB 3.0 hosts. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-12-11USB: xhci: Add tests for TRB address translation.Sarah Sharp
It's not surprising that the transfer request buffer (TRB) physical to virtual address translation function has bugs in it, since I wrote most of it at 4am last October. Add a test suite to check the TRB math. This runs at memory initialization time, and causes the driver to fail to load if the TRB math fails. Please excuse the excessively long lines in the test vectors; they can't really be made shorter and still be readable. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-12-11USB: xhci: Remove unused HCD statistics code.Sarah Sharp
CONFIG_USB_HCD_STAT was used in an abandoned patch to track host controller throughput statistics. Since CONFIG_USB_HCD_STAT will never be defined, remove code that can never run. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-12-11USB: xhci: Add watchdog timer for URB cancellation.Sarah Sharp
In order to giveback a canceled URB, we must ensure that the xHCI hardware will not access the buffer in an URB. We can't modify the buffer pointers on endpoint rings without issuing and waiting for a stop endpoint command. Since URBs can be canceled in interrupt context, we can't wait on that command. The old code trusted that the host controller would respond to the command, and would giveback the URBs in the event handler. If the hardware never responds to the stop endpoint command, the URBs will never be completed, and we might hang the USB subsystem. Implement a watchdog timer that is spawned whenever a stop endpoint command is queued. If a stop endpoint command event is found on the event ring during an interrupt, we need to stop the watchdog timer with del_timer(). Since del_timer() can fail if the timer is running and waiting on the xHCI lock, we need a way to signal to the timer that everything is fine and it should exit. If we simply clear EP_HALT_PENDING, a new stop endpoint command could sneak in and set it before the watchdog timer can grab the lock. Instead we use a combination of the EP_HALT_PENDING flag and a counter for the number of pending stop endpoint commands (xhci_virt_ep->stop_cmds_pending). If we need to cancel the watchdog timer and del_timer() succeeds, we decrement the number of pending stop endpoint commands. If del_timer() fails, we leave the number of pending stop endpoint commands alone. In either case, we clear the EP_HALT_PENDING flag. The timer will decrement the number of pending stop endpoint commands once it obtains the lock. If the timer is the tail end of the last stop endpoint command (xhci_virt_ep->stop_cmds_pending == 0), and the endpoint's command is still pending (EP_HALT_PENDING is set), we assume the host is dying. The watchdog timer will set XHCI_STATE_DYING, try to halt the xHCI host, and give back all pending URBs. Various other places in the driver need to check whether the xHCI host is dying. If the interrupt handler ever notices, it should immediately stop processing events. The URB enqueue function should also return -ESHUTDOWN. The URB dequeue function should simply return the value of usb_hcd_check_unlink_urb() and the watchdog timer will take care of giving the URB back. When a device is disconnected, the xHCI hardware structures should be freed without issuing a disable slot command (since the hardware probably won't respond to it anyway). The debugging polling loop should stop polling if the host is dying. When a device is disconnected, any pending watchdog timers are killed with del_timer_sync(). It must be synchronous so that the watchdog timer doesn't attempt to access the freed endpoint structures. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-12-11USB: xhci: Handle URB cancel, complete and resubmit race.Sarah Sharp
In the old code, there was a race condition between the stop endpoint command and the URB submission process. When the stop endpoint command is handled by the event handler, the endpoint ring is assumed to be stopped. When a stop endpoint command is queued, URB submissions are to not ring the doorbell. The old code would check the number of pending URBs to be canceled, and would not ring the doorbell if it was non-zero. However, the following race condition could occur with the old code: 1. Cancel an URB, add it to the list of URBs to be canceled, queue the stop endpoint command, and increment ep->cancels_pending to 1. 2. The URB finishes on the HW, and an event is enqueued to the event ring (at the same time as 1). 3. The stop endpoint command finishes, and the endpoint is halted. An event is queued to the event ring. 4. The event handler sees the finished URB, notices it was to be canceled, decrements ep->cancels_pending to 0, and removes it from the to be canceled list. 5. The event handler drops the lock and gives back the URB. The completion handler requeues the URB (or a different driver enqueues a new URB). This causes the endpoint's doorbell to be rung, since ep->cancels_pending == 0. The endpoint is now running. 6. A second URB is canceled, and it's added to the canceled list. Since ep->cancels_pending == 0, a new stop endpoint command is queued, and ep->cancels_pending is incremented to 1. 7. The event handler then sees the completed stop endpoint command. The handler assumes the endpoint is stopped, but it isn't. It attempts to move the dequeue pointer or change TDs to cancel the second URB, while the hardware is actively accessing the endpoint ring. To eliminate this race condition, a new endpoint state bit is introduced, EP_HALT_PENDING. When this bit is set, a stop endpoint command has been queued, and the command handler has not begun to process the URB cancellation list yet. The endpoint doorbell should not be rung when this is set. Set this when a stop endpoint command is queued, clear it when the handler for that command runs, and check if it's set before ringing a doorbell. ep->cancels_pending is eliminated, because it is no longer used. Make sure to ring the doorbell for an endpoint when the stop endpoint command handler runs, even if the canceled URB list is empty. All canceled URBs could have completed and new URBs could have been enqueued without the doorbell being rung before the command was handled. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-11-17USB: xhci: Fix TRB physical to virtual address translation.Sarah Sharp
The trb_in_td() function in the xHCI driver is supposed to translate a physical transfer buffer request (TRB) into a virtual pointer to the ring segment that TRB is in. Unfortunately, a mistake in this function may cause endless loops as the driver searches through the linked list of ring segments over and over again. Fix a couple bugs that may lead to loops or bad output: 1. Bail out if we get a NULL pointer when translating the segment's private structure and the starting DMA address of the segment chunk. If this happens, we've been handed a starting TRB pointer from a different ring. 2. Make sure the function works when there's multiple segments in the ring. In the while loop to search through the ring segments, use the current segment variable (cur_seg), rather than the starting segment variable (start_seg) that is passed in. 3. Stop searching the ring if we've run through all the segments in the ring. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-09-23USB: xhci: Support USB hubs.Sarah Sharp
For a USB hub to work under an xHCI host controller, the xHC's internal scheduler must be made aware of the hub's characteristics. Add an xHCI hook that the USB core will call after it fetches the hub descriptor. This hook will add hub information to the slot context for that device, including whether it has multiple TTs or a single TT, the number of ports on the hub, and TT think time. Setting up the slot context for the device is different for 0.95 and 0.96 xHCI host controllers. Some of the slot context reserved fields in the 0.95 specification were changed into hub fields in the 0.96 specification. Don't set the TT think time or number of ports for a hub if we're dealing with a 0.95-compliant xHCI host controller. The 0.95 xHCI specification says that to modify the hub flag, we need to issue an evaluate context command. The 0.96 specification says that flag can be set with a configure endpoint command. Issue the correct command based on the version reported by the hardware. This patch does not add support for multi-TT hubs. Multi-TT hubs expose a single TT on alt setting 0, and multi-TT on alt setting 1. The xHCI driver can't handle setting alternate interfaces yet. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-09-23USB: xhci: Fix command wait list handling.Sarah Sharp
In the xHCI driver, configure endpoint commands that are submitted to the hardware may involve one of two data structures. If the configure endpoint command is setting up a new configuration or modifying max packet sizes, the data structures and completions are statically allocated in the xhci_virt_device structure. If the command is being used to set up streams or add hub information, then the data structures are dynamically allocated, and placed on a device command waiting list. Break out the code to check whether a completed command is in the device command waiting list. Fix a subtle bug in the old code: continue processing the command if the command isn't in the wait list. In the old code, if there was a command in the wait list, but it didn't match the completed command, the completed command event would be dropped. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-09-23USB: xhci: Change how xHCI commands are handled.Sarah Sharp
Some commands to the xHCI hardware cannot be allowed to fail due to out of memory issues or the command ring being full. Add a way to reserve a TRB on the command ring, and make all command queueing functions indicate whether they are using a reserved TRB. Add a way to pre-allocate all the memory a command might need. A command needs an input context, a variable to store the status, and (optionally) a completion for the caller to wait on. Change all code that assumes the input device context, status, and completion for a command is stored in the xhci virtual USB device structure (xhci_virt_device). Store pending completions in a FIFO in xhci_virt_device. Make the event handler for a configure endpoint command check to see whether a pending command in the list has completed. We need to use separate input device contexts for some configure endpoint commands, since multiple drivers can submit requests at the same time that require a configure endpoint command. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-09-23USB: xhci: Endpoint representation refactoring.Sarah Sharp
The xhci_ring structure contained information that is really related to an endpoint, not a ring. This will cause problems later when endpoint streams are supported and there are multiple rings per endpoint. Move the endpoint state and cancellation information into a new virtual endpoint structure, xhci_virt_ep. The list of TRBs to be cancelled should be per endpoint, not per ring, for easy access. There can be only one TRB that the endpoint stopped on after a stop endpoint command (even with streams enabled); move the stopped TRB information into the new virtual endpoint structure. Also move the 31 endpoint rings and temporary ring storage from the virtual device structure (xhci_virt_device) into the virtual endpoint structure (xhci_virt_ep). Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>