xHCI host controller failure during DMA transfers

[Bora Sahin <bora.sahin@xxxxxxxxxxx>]

Hi all,

We have some problems regarding the use of Freesco Logic FL1009 xhci
controller in our embedded board.

xHCI is connected to the system through PCIe. Our kernel is
linux-2.6.30 so did not have xHCI support. Fresco Logic provided
patches (in the form of file replacements). We applied those patches
and put it into the test. We are using a USB stick (filesystem is
vfat) for this purpose. We can mount the disk without any problem, ls
seems working, however, when we try to read files (60, 70KB) (by using
cat) and/or creating dummy files on it, it crashes. We opened DEBUG
feature and caught some log while this is happening.

# ./filecreate bora 100000 1000 -> This is the application. It creates
a file whose size is ~90M

usb 1-1: ep 0x2 - urb len = 0x1f (31), addr = 0x3472000, num_trbs = 1
xhci_hcd 0000:00:00.0: Endpoint state = 0x1
xhci_hcd 0000:00:00.0: Ring enq = 0x313d430 (DMA)
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 32'h79003004, 32'h4, 4'hf);
xhci_hcd 0000:00:00.0: op reg status = 00000008
xhci_hcd 0000:00:00.0: Event ring dequeue ptr:
xhci_hcd 0000:00:00.0: @313c4d0 0313d420 00000000 01000000 01048000
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 32'h79000084, 32'h8, 4'hf);
xhci_hcd 0000:00:00.0: In xhci_handle_event
xhci_hcd 0000:00:00.0: xhci_handle_event - OS owns TRB
xhci_hcd 0000:00:00.0: xhci_handle_event - calling handle_tx_event
xhci_hcd 0000:00:00.0: handle_tx_event - ep index = 3
xhci_hcd 0000:00:00.0: Successful bulk transfer!

-----------
I suppose the above is okay, and it continues for a while.
-----------

usb 1-1: ep 0x2 - asked for 31 bytes, 0 bytes untransferred
xhci_hcd 0000:00:00.0: Ring deq = 0x313d430 (DMA)
xhci_hcd 0000:00:00.0: Event ring deq = 0x313c4e0 (DMA)
xhci_hcd 0000:00:00.0: Giveback URB 834087c0, len = 31, status = 0
xhci_hcd 0000:00:00.0: xhci_handle_event - returned from handle_tx_event
xhci_hcd 0000:00:00.0: In xhci_handle_event
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 64'h79002038,
64'h313c4e8, 4'hf);
xhci_hcd 0000:00:00.0: count sg list trbs:
xhci_hcd 0000:00:00.0:  sg #0: dma = 0x13d6000, len = 0x1400 (5120),
num_trbs = 1
xhci_hcd 0000:00:00.0:
usb 1-1: ep 0x81 - urb len = 5120, sglist used, num_trbs = 1
xhci_hcd 0000:00:00.0: Endpoint state = 0x1
xhci_hcd 0000:00:00.0: First length to xfer from 1st sglist entry = 5120
xhci_hcd 0000:00:00.0:  sg entry: dma = 0x13d6000, len = 0x1400
(5120), 64KB boundary at 0x13e0000, end dma = 0x13d7400
xhci_hcd 0000:00:00.0: Ring enq = 0x313d0a0 (DMA)
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 32'h79003004, 32'h3, 4'hf);
xhci_hcd 0000:00:00.0: op reg status = 00000008
xhci_hcd 0000:00:00.0: Event ring dequeue ptr:
xhci_hcd 0000:00:00.0: @313c4e0 0313d090 00000000 01000000 01038000
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 32'h79000084, 32'h8, 4'hf);
xhci_hcd 0000:00:00.0: In xhci_handle_event
xhci_hcd 0000:00:00.0: xhci_handle_event - OS owns TRB
xhci_hcd 0000:00:00.0: xhci_handle_event - calling handle_tx_event
xhci_hcd 0000:00:00.0: handle_tx_event - ep index = 2
xhci_hcd 0000:00:00.0: Successful bulk transfer!
usb 1-1: ep 0x81 - asked for 5120 bytes, 0 bytes untransferred
xhci_hcd 0000:00:00.0: Ring deq = 0x313d0a0 (DMA)
xhci_hcd 0000:00:00.0: Event ring deq = 0x313c4f0 (DMA)
xhci_hcd 0000:00:00.0: Giveback URB 834086c0, len = 5120, status = 0
xhci_hcd 0000:00:00.0: xhci_handle_event - returned from handle_tx_event
xhci_hcd 0000:00:00.0: In xhci_handle_event
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 64'h79002038,
64'h313c4f8, 4'hf);
usb 1-1: ep 0x81 - urb len = 0xd (13), addr = 0x3472000, num_trbs = 1
xhci_hcd 0000:00:00.0: Endpoint state = 0x1
xhci_hcd 0000:00:00.0: Ring enq = 0x313d0b0 (DMA)
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 32'h79003004, 32'h3, 4'hf);
xhci_hcd 0000:00:00.0: op reg status = 00000008
xhci_hcd 0000:00:00.0: Event ring dequeue ptr:
xhci_hcd 0000:00:00.0: @313c4f0 0313d0a0 00000000 01000000 01038000
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 32'h79000084, 32'h8, 4'hf);
xhci_hcd 0000:00:00.0: In xhci_handle_event
xhci_hcd 0000:00:00.0: xhci_handle_event - OS owns TRB
xhci_hcd 0000:00:00.0: xhci_handle_event - calling handle_tx_event
xhci_hcd 0000:00:00.0: handle_tx_event - ep index = 2
xhci_hcd 0000:00:00.0: Successful bulk transfer!
usb 1-1: ep 0x81 - asked for 13 bytes, 0 bytes untransferred
xhci_hcd 0000:00:00.0: Ring deq = 0x313d0b0 (DMA)
xhci_hcd 0000:00:00.0: Event ring deq = 0x313c500 (DMA)
xhci_hcd 0000:00:00.0: Giveback URB 834087c0, len = 13, status = 0
xhci_hcd 0000:00:00.0: xhci_handle_event - returned from handle_tx_event
xhci_hcd 0000:00:00.0: In xhci_handle_event
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 64'h79002038,
64'h313c508, 4'hf);
usb 1-1: ep 0x2 - urb len = 0x1f (31), addr = 0x3472000, num_trbs = 1
xhci_hcd 0000:00:00.0: Endpoint state = 0x1
xhci_hcd 0000:00:00.0: Ring enq = 0x313d440 (DMA)
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 32'h79003004, 32'h4, 4'hf);
xhci_hcd 0000:00:00.0: op reg status = 00000008
xhci_hcd 0000:00:00.0: Event ring dequeue ptr:
xhci_hcd 0000:00:00.0: @313c500 0313d430 00000000 01000000 01048000
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 32'h79000084, 32'h8, 4'hf);
xhci_hcd 0000:00:00.0: In xhci_handle_event
xhci_hcd 0000:00:00.0: xhci_handle_event - OS owns TRB
xhci_hcd 0000:00:00.0: xhci_handle_event - calling handle_tx_event
xhci_hcd 0000:00:00.0: handle_tx_event - ep index = 3
xhci_hcd 0000:00:00.0: Successful bulk transfer!
usb 1-1: ep 0x2 - asked for 31 bytes, 0 bytes untransferred
xhci_hcd 0000:00:00.0: Ring deq = 0x313d440 (DMA)
xhci_hcd 0000:00:00.0: Event ring deq = 0x313c510 (DMA)
xhci_hcd 0000:00:00.0: Giveback URB 834087c0, len = 31, status = 0
xhci_hcd 0000:00:00.0: xhci_handle_event - returned from handle_tx_event
xhci_hcd 0000:00:00.0: In xhci_handle_event
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 64'h79002038,
64'h313c518, 4'hf);
xhci_hcd 0000:00:00.0: count sg list trbs:
xhci_hcd 0000:00:00.0:  sg #0: dma = 0x13b7600, len = 0x200 (512), num_trbs = 1
xhci_hcd 0000:00:00.0:
usb 1-1: ep 0x81 - urb len = 512, sglist used, num_trbs = 1
xhci_hcd 0000:00:00.0: Endpoint state = 0x1
xhci_hcd 0000:00:00.0: First length to xfer from 1st sglist entry = 512
xhci_hcd 0000:00:00.0:  sg entry: dma = 0x13b7600, len = 0x200 (512),
64KB boundary at 0x13c0000, end dma = 0x13b7800
xhci_hcd 0000:00:00.0: Ring enq = 0x313d0c0 (DMA)
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 32'h79003004, 32'h3, 4'hf);
xhci_hcd 0000:00:00.0: op reg status = 00000008
xhci_hcd 0000:00:00.0: Event ring dequeue ptr:
xhci_hcd 0000:00:00.0: @313c510 0313d0b0 00000000 01000000 01038000
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 32'h79000084, 32'h8, 4'hf);
xhci_hcd 0000:00:00.0: In xhci_handle_event
xhci_hcd 0000:00:00.0: xhci_handle_event - OS owns TRB
xhci_hcd 0000:00:00.0: xhci_handle_event - calling handle_tx_event
xhci_hcd 0000:00:00.0: handle_tx_event - ep index = 2
xhci_hcd 0000:00:00.0: Successful bulk transfer!
usb 1-1: ep 0x81 - asked for 512 bytes, 0 bytes untransferred
xhci_hcd 0000:00:00.0: Ring deq = 0x313d0c0 (DMA)
xhci_hcd 0000:00:00.0: Event ring deq = 0x313c520 (DMA)
xhci_hcd 0000:00:00.0: Giveback URB 834086c0, len = 512, status = 0
xhci_hcd 0000:00:00.0: xhci_handle_event - returned from handle_tx_event
xhci_hcd 0000:00:00.0: In xhci_handle_event
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 64'h79002038,
64'h313c528, 4'hf);
usb 1-1: ep 0x81 - urb len = 0xd (13), addr = 0x3472000, num_trbs = 1
xhci_hcd 0000:00:00.0: Endpoint state = 0x1
xhci_hcd 0000:00:00.0: Ring enq = 0x313d0d0 (DMA)
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 32'h79003004, 32'h3, 4'hf);
xhci_hcd 0000:00:00.0: op reg status = 00000008
xhci_hcd 0000:00:00.0: Event ring dequeue ptr:
xhci_hcd 0000:00:00.0: @313c520 0313d0c0 00000000 01000000 01038000
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 32'h79000084, 32'h8, 4'hf);
xhci_hcd 0000:00:00.0: In xhci_handle_event
xhci_hcd 0000:00:00.0: xhci_handle_event - OS owns TRB
xhci_hcd 0000:00:00.0: xhci_handle_event - calling handle_tx_event
xhci_hcd 0000:00:00.0: handle_tx_event - ep index = 2
xhci_hcd 0000:00:00.0: Successful bulk transfer!
usb 1-1: ep 0x81 - asked for 13 bytes, 0 bytes untransferred
xhci_hcd 0000:00:00.0: Ring deq = 0x313d0d0 (DMA)
xhci_hcd 0000:00:00.0: Event ring deq = 0x313c530 (DMA)
xhci_hcd 0000:00:00.0: Giveback URB 834087c0, len = 13, status = 0
xhci_hcd 0000:00:00.0: xhci_handle_event - returned from handle_tx_event
xhci_hcd 0000:00:00.0: In xhci_handle_event
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 64'h79002038,
64'h313c538, 4'hf);
usb 1-1: ep 0x2 - urb len = 0x1f (31), addr = 0x3472000, num_trbs = 1
xhci_hcd 0000:00:00.0: Endpoint state = 0x1
xhci_hcd 0000:00:00.0: Ring enq = 0x313d450 (DMA)
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 32'h79003004, 32'h4, 4'hf);
xhci_hcd 0000:00:00.0: op reg status = 00000008
xhci_hcd 0000:00:00.0: Event ring dequeue ptr:
xhci_hcd 0000:00:00.0: @313c530 0313d440 00000000 01000000 01048000
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 32'h79000084, 32'h8, 4'hf);
xhci_hcd 0000:00:00.0: In xhci_handle_event
xhci_hcd 0000:00:00.0: xhci_handle_event - OS owns TRB
xhci_hcd 0000:00:00.0: xhci_handle_event - calling handle_tx_event
xhci_hcd 0000:00:00.0: handle_tx_event - ep index = 3
xhci_hcd 0000:00:00.0: Successful bulk transfer!
usb 1-1: ep 0x2 - asked for 31 bytes, 0 bytes untransferred
xhci_hcd 0000:00:00.0: Ring deq = 0x313d450 (DMA)
xhci_hcd 0000:00:00.0: Event ring deq = 0x313c540 (DMA)
xhci_hcd 0000:00:00.0: Giveback URB 834087c0, len = 31, status = 0
xhci_hcd 0000:00:00.0: xhci_handle_event - returned from handle_tx_event
xhci_hcd 0000:00:00.0: In xhci_handle_event
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 64'h79002038,
64'h313c548, 4'hf);
xhci_hcd 0000:00:00.0: count sg list trbs:
xhci_hcd 0000:00:00.0:  sg #0: dma = 0x13b7800, len = 0x200 (512), num_trbs = 1
xhci_hcd 0000:00:00.0:
usb 1-1: ep 0x81 - urb len = 512, sglist used, num_trbs = 1
xhci_hcd 0000:00:00.0: Endpoint state = 0x1
xhci_hcd 0000:00:00.0: First length to xfer from 1st sglist entry = 512
xhci_hcd 0000:00:00.0:  sg entry: dma = 0x13b7800, len = 0x200 (512),
64KB boundary at 0x13c0000, end dma = 0x13b7a00
xhci_hcd 0000:00:00.0: Ring enq = 0x313d0e0 (DMA)
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 32'h79003004, 32'h3, 4'hf);
xhci_hcd 0000:00:00.0: op reg status = 00000008
xhci_hcd 0000:00:00.0: Event ring dequeue ptr:
xhci_hcd 0000:00:00.0: @313c540 0313d0d0 00000000 01000000 01038000
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 32'h79000084, 32'h8, 4'hf);
xhci_hcd 0000:00:00.0: In xhci_handle_event
xhci_hcd 0000:00:00.0: xhci_handle_event - OS owns TRB
xhci_hcd 0000:00:00.0: xhci_handle_event - calling handle_tx_event
xhci_hcd 0000:00:00.0: handle_tx_event - ep index = 2
xhci_hcd 0000:00:00.0: Successful bulk transfer!
usb 1-1: ep 0x81 - asked for 512 bytes, 0 bytes untransferred
xhci_hcd 0000:00:00.0: Ring deq = 0x313d0e0 (DMA)
xhci_hcd 0000:00:00.0: Event ring deq = 0x313c550 (DMA)
xhci_hcd 0000:00:00.0: Giveback URB 834086c0, len = 512, status = 0
xhci_hcd 0000:00:00.0: xhci_handle_event - returned from handle_tx_event
xhci_hcd 0000:00:00.0: In xhci_handle_event
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 64'h79002038,
64'h313c558, 4'hf);
usb 1-1: ep 0x81 - urb len = 0xd (13), addr = 0x3472000, num_trbs = 1
xhci_hcd 0000:00:00.0: Endpoint state = 0x1
xhci_hcd 0000:00:00.0: Ring enq = 0x313d0f0 (DMA)
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 32'h79003004, 32'h3, 4'hf);
xhci_hcd 0000:00:00.0: op reg status = 00000008
xhci_hcd 0000:00:00.0: Event ring dequeue ptr:
xhci_hcd 0000:00:00.0: @313c550 0313d0e0 00000000 01000000 01038000
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 32'h79000084, 32'h8, 4'hf);
xhci_hcd 0000:00:00.0: In xhci_handle_event
xhci_hcd 0000:00:00.0: xhci_handle_event - OS owns TRB
xhci_hcd 0000:00:00.0: xhci_handle_event - calling handle_tx_event
xhci_hcd 0000:00:00.0: handle_tx_event - ep index = 2
xhci_hcd 0000:00:00.0: Successful bulk transfer!
usb 1-1: ep 0x81 - asked for 13 bytes, 0 bytes untransferred
xhci_hcd 0000:00:00.0: Ring deq = 0x313d0f0 (DMA)
xhci_hcd 0000:00:00.0: Event ring deq = 0x313c560 (DMA)
xhci_hcd 0000:00:00.0: Giveback URB 834087c0, len = 13, status = 0
xhci_hcd 0000:00:00.0: xhci_handle_event - returned from handle_tx_event
xhci_hcd 0000:00:00.0: In xhci_handle_event
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 64'h79002038,
64'h313c568, 4'hf);
usb 1-1: ep 0x2 - urb len = 0x1f (31), addr = 0x3472000, num_trbs = 1
xhci_hcd 0000:00:00.0: Endpoint state = 0x1
xhci_hcd 0000:00:00.0: Ring enq = 0x313d460 (DMA)
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 32'h79003004, 32'h4, 4'hf);
xhci_hcd 0000:00:00.0: op reg status = 00000008
xhci_hcd 0000:00:00.0: Event ring dequeue ptr:
xhci_hcd 0000:00:00.0: @313c560 0313d450 00000000 01000000 01048000
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 32'h79000084, 32'h8, 4'hf);
xhci_hcd 0000:00:00.0: In xhci_handle_event
xhci_hcd 0000:00:00.0: xhci_handle_event - OS owns TRB
xhci_hcd 0000:00:00.0: xhci_handle_event - calling handle_tx_event
xhci_hcd 0000:00:00.0: handle_tx_event - ep index = 3
xhci_hcd 0000:00:00.0: Successful bulk transfer!
usb 1-1: ep 0x2 - asked for 31 bytes, 0 bytes untransferred

-----------
I think all of the above log is okay.

Then things start going bad. Look at the below output:
-----------

xhci_hcd 0000:00:00.0: Ring deq = 0x313d460 (DMA)
xhci_hcd 0000:00:00.0: Event ring deq = 0x313c570 (DMA)
xhci_hcd 0000:00:00.0: Giveback URB 834087c0, len = 31, status = 0
xhci_hcd 0000:00:00.0: xhci_handle_event - returned from handle_tx_event
xhci_hcd 0000:00:00.0: In xhci_handle_event
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 64'h79002038,
64'h313c578, 4'hf);
xhci_hcd 0000:00:00.0: count sg list trbs:
xhci_hcd 0000:00:00.0: sg #0: dma = 0x13b4000, len = 0x2000 (8192), num_trbs = 1
xhci_hcd 0000:00:00.0: sg #1: dma = 0x1384000, len = 0x2000 (8192), num_trbs = 1
xhci_hcd 0000:00:00.0: sg #2: dma = 0x1388000, len = 0x2000 (8192), num_trbs = 1
xhci_hcd 0000:00:00.0: sg #3: dma = 0x138c000, len = 0x2000 (8192), num_trbs = 1
xhci_hcd 0000:00:00.0: sg #4: dma = 0x1390000, len = 0x2000 (8192), num_trbs = 1
xhci_hcd 0000:00:00.0: sg #5: dma = 0x1394000, len = 0x2000 (8192), num_trbs = 1
xhci_hcd 0000:00:00.0: sg #6: dma = 0x1398000, len = 0x2000 (8192), num_trbs = 1
xhci_hcd 0000:00:00.0: sg #7: dma = 0x139c000, len = 0x2000 (8192), num_trbs = 1
xhci_hcd 0000:00:00.0: sg #8: dma = 0x600000, len = 0x2000 (8192), num_trbs = 1
xhci_hcd 0000:00:00.0: sg #9: dma = 0x604000, len = 0x2000 (8192), num_trbs = 1
xhci_hcd 0000:00:00.0: sg #10: dma = 0x608000, len = 0xa000 (40960),
num_trbs = 2
xhci_hcd 0000:00:00.0:
usb 1-1: ep 0x2 - urb len = 122880, sglist used, num_trbs = 12
xhci_hcd 0000:00:00.0: Endpoint state = 0x1
xhci_hcd 0000:00:00.0: First length to xfer from 1st sglist entry = 8192
xhci_hcd 0000:00:00.0: sg entry: dma = 0x13b4000, len = 0x2000 (8192),
64KB boundary at 0x13c0000, end dma = 0x13b6000
xhci_hcd 0000:00:00.0: Ring enq = 0x313d470 (DMA)
xhci_hcd 0000:00:00.0: sg entry: dma = 0x1384000, len = 0x2000 (8192),
64KB boundary at 0x1390000, end dma = 0x1386000
xhci_hcd 0000:00:00.0: Ring enq = 0x313d480 (DMA)
xhci_hcd 0000:00:00.0: sg entry: dma = 0x1388000, len = 0x2000 (8192),
64KB boundary at 0x1390000, end dma = 0x138a000
xhci_hcd 0000:00:00.0: Ring enq = 0x313d490 (DMA)
xhci_hcd 0000:00:00.0: sg entry: dma = 0x138c000, len = 0x2000 (8192),
64KB boundary at 0x1390000, end dma = 0x138e000
xhci_hcd 0000:00:00.0: Ring enq = 0x313d4a0 (DMA)
xhci_hcd 0000:00:00.0: sg entry: dma = 0x1390000, len = 0x2000 (8192),
64KB boundary at 0x13a0000, end dma = 0x1392000
xhci_hcd 0000:00:00.0: Ring enq = 0x313d4b0 (DMA)
xhci_hcd 0000:00:00.0: sg entry: dma = 0x1394000, len = 0x2000 (8192),
64KB boundary at 0x13a0000, end dma = 0x1396000
xhci_hcd 0000:00:00.0: Ring enq = 0x313d4c0 (DMA)
xhci_hcd 0000:00:00.0: sg entry: dma = 0x1398000, len = 0x2000 (8192),
64KB boundary at 0x13a0000, end dma = 0x139a000
xhci_hcd 0000:00:00.0: Ring enq = 0x313d4d0 (DMA)
xhci_hcd 0000:00:00.0: sg entry: dma = 0x139c000, len = 0x2000 (8192),
64KB boundary at 0x13a0000, end dma = 0x139e000
xhci_hcd 0000:00:00.0: Ring enq = 0x313d4e0 (DMA)
xhci_hcd 0000:00:00.0: sg entry: dma = 0x600000, len = 0x2000 (8192),
64KB boundary at 0x610000, end dma = 0x602000
xhci_hcd 0000:00:00.0: Ring enq = 0x313d4f0 (DMA)
xhci_hcd 0000:00:00.0: sg entry: dma = 0x604000, len = 0x2000 (8192),
64KB boundary at 0x610000, end dma = 0x606000
xhci_hcd 0000:00:00.0: Ring enq = 0x313d500 (DMA)
xhci_hcd 0000:00:00.0: sg entry: dma = 0x608000, len = 0x8000 (32768),
64KB boundary at 0x610000, end dma = 0x610000
xhci_hcd 0000:00:00.0: Ring enq = 0x313d510 (DMA)
xhci_hcd 0000:00:00.0: sg entry: dma = 0x610000, len = 0x2000 (8192),
64KB boundary at 0x620000, end dma = 0x612000
xhci_hcd 0000:00:00.0: Ring enq = 0x313d520 (DMA)
xhci_hcd 0000:00:00.0: `MEM_WRITE_DWORD(3'b000, 32'h79003004, 32'h4, 4'hf);
xhci_hcd 0000:00:00.0: Cancel URB 834086c0

After that it prints event_ring, command_ring, endpoint_ring etc. You
can find the details in the log file.

Could you please comment on that?

Regards,

PS: I am not subscribed to the list. Please cc to me.

--
Bora Sahin
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