On 16.12.2022 23.32, Ladislav Michl wrote:
On Fri, Dec 16, 2022 at 12:13:23PM +0200, Mathias Nyman wrote:
On 15.12.2022 18.12, Ladislav Michl wrote:
+Cc Mathias as he last touched this code path and may know more :)
On Tue, Dec 06, 2022 at 02:17:08PM +0100, Ladislav Michl wrote:
On Mon, Dec 05, 2022 at 10:27:57PM +0100, Ladislav Michl wrote:
I'm running current linux.git on custom Marvell OCTEON III CN7020
based board. USB devices like FTDI (idVendor=0403, idProduct=6001,
bcdDevice= 6.00) Realtek WiFi dongle (idVendor=0bda, idProduct=8179,
bcdDevice= 0.00) works without issues, while Ralink WiFi dongle
(idVendor=148f, idProduct=5370, bcdDevice= 1.01) kills the host on
disconnect:
xhci-hcd xhci-hcd.0.auto: xHCI host not responding to stop endpoint command
xhci-hcd xhci-hcd.0.auto: xHCI host controller not responding, assume dead
xhci-hcd xhci-hcd.0.auto: HC died; cleaning up
Unfortunately I do not have a datasheet for CN7020 SoC, so it is hard
to tell if there is any errata :/ In case anyone see a clue in debug
logs bellow, I'll happily give it a try.
So I do have datasheet now. As a wild guess I tried to use dlmc_ref_clk0
instead of dlmc_ref_clk1 as a refclk-type-ss and it fixed unplug death.
I have no clue why, but anyway - sorry for the noise :) Perhaps Octeon's
clock init is worth to be verified...
After all whenever xhci dies with "xHCI host not responding to stop endpoint
command" depends also on temperature, so there seems to be race somewhere.
As a quick and dirty verification, whenever xhci really died, following patch
was tested and it fixed issue. It just treats ep as if stop endpoint command
succeeded. Any clues? I'll happily provide more traces.
It's possible the controller did complete the stop endpoint command but driver
didn't get the interrupt for the event for some reason.
Looks like controller didn't complete the stop endpoint command.
Event for last completed command (before cycle bit change "c" -> "C") was:
0x00000000028f55a0: TRB 00000000035e81a0 status 'Success' len 0 slot 1 ep 0 type 'Command Completion Event' flags e:c,
This was for command at 35e81a0, which in the command ring was:
0x00000000035e81a0: Reset Endpoint Command: ctx 0000000000000000 slot 1 ep 3 flags T:c
The stop endpoint command was the next command queued, at 35e81b0:
0x00000000035e81b0: Stop Ring Command: slot 1 sp 0 ep 3 flags c
There were a lot of URBs queued for this device, and they are cancelled one by one after disconnect.
Was this the only device connected? If so does connecting another usb device to another root port help?
Just to test if the host for some reason partially stops a while after last device disconnect?
Another thing is that the stop endpoint command fails after three soft reset tries,
does disabling soft reset help?
Either add somwehere:
xhci->quirks |= XHCI_NO_SOFT_RETRY;
or:
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index b07d3740f554..aa1c92a72916 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -2515,7 +2515,7 @@ static int process_bulk_intr_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
remaining = 0;
break;
case COMP_USB_TRANSACTION_ERROR:
- if (xhci->quirks & XHCI_NO_SOFT_RETRY ||
+ if (1 || xhci->quirks & XHCI_NO_SOFT_RETRY ||
(ep_ring->err_count++ > MAX_SOFT_RETRY) ||
le32_to_cpu(slot_ctx->tt_info) & TT_SLOT)
break;
Just for reference, the last events and commands:
# cat /sys/kernel/debug/usb/xhci/xhci-hcd.0.auto/event-ring/trbs
0x00000000028f5520: TRB 00000000036c9ce0 status 'Success' len 0 slot 1 ep 1 type 'Transfer Event' flags e:c
0x00000000028f5530: TRB 00000000036c9d10 status 'Success' len 0 slot 1 ep 1 type 'Transfer Event' flags e:c
0x00000000028f5540: TRB 00000000030fa9a0 status 'USB Transaction Error' len 3860 slot 1 ep 3 type 'Transfer Event' flags e:c
0x00000000028f5550: TRB 00000000035e8180 status 'Success' len 0 slot 1 ep 0 type 'Command Completion Event' flags e:c
0x00000000028f5560: TRB 0000000001000000 status 'Success' len 0 slot 0 ep 0 type 'Port Status Change Event' flags e:c
0x00000000028f5570: TRB 00000000030fa9a0 status 'USB Transaction Error' len 3860 slot 1 ep 3 type 'Transfer Event' flags e:c
0x00000000028f5580: TRB 00000000035e8190 status 'Success' len 0 slot 1 ep 0 type 'Command Completion Event' flags e:c
0x00000000028f5590: TRB 00000000030fa9a0 status 'USB Transaction Error' len 3860 slot 1 ep 3 type 'Transfer Event' flags e:c
0x00000000028f55a0: TRB 00000000035e81a0 status 'Success' len 0 slot 1 ep 0 type 'Command Completion Event' flags e:c
# cat /sys/kernel/debug/usb/xhci/xhci-hcd.0.auto/command-ring/trbs
0x00000000035e8120: Stop Ring Command: slot 1 sp 0 ep 3 flags c
0x00000000035e8130: Set TR Dequeue Pointer Command: deq 00000000030fa891 stream 0 slot 1 ep 3 flags c
0x00000000035e8140: Stop Ring Command: slot 1 sp 0 ep 3 flags c
0x00000000035e8150: Set TR Dequeue Pointer Command: deq 00000000030fa8a1 stream 0 slot 1 ep 3 flags c
0x00000000035e8160: Stop Ring Command: slot 1 sp 0 ep 3 flags c
0x00000000035e8170: Set TR Dequeue Pointer Command: deq 00000000030fa8b1 stream 0 slot 1 ep 3 flags c
0x00000000035e8180: Reset Endpoint Command: ctx 0000000000000000 slot 1 ep 3 flags T:c
0x00000000035e8190: Reset Endpoint Command: ctx 0000000000000000 slot 1 ep 3 flags T:c
0x00000000035e81a0: Reset Endpoint Command: ctx 0000000000000000 slot 1 ep 3 flags T:c
0x00000000035e81b0: Stop Ring Command: slot 1 sp 0 ep 3 flags c
-Mathias
