On 3/17/22 23:05, qianfan wrote:
[ ... ]
So I think it's a bug of MUSB, not caused by dev_WARN_ONCE. But I can't check which stop hrtimer.
Correct. Look at the code:
static void musb_h_tx_flush_fifo(struct musb_hw_ep *ep)
{
...
int retries = 1000;
...
while (csr & MUSB_TXCSR_FIFONOTEMPTY) {
...
if (dev_WARN_ONCE(musb->controller, retries-- < 1,
"Could not flush host TX%d fifo: csr: %04x\n",
ep->epnum, csr))
return;
mdelay(1);
}
This is where the one second comes from. The function is called from
musb_urb_dequeue() which disables interrupts. This forces a hard stall
of the kernel for a full second.
There is nothing we can do about that in the watchdog driver.
Guenter
