Messages in this thread | | | Date | Thu, 5 Jan 2023 11:29:11 +0800 | Subject | Re: [PATCH] usb: dwc3: Clear DWC3_EVENT_PENDING when count is 0 | From | Linyu Yuan <> |
| |
On 1/2/2023 1:08 PM, JaeHun Jung wrote: > Sometimes very rarely, The count is 0 and the DWC3 flag is set has status. > It must not have these status. Because, It can make happen interrupt storming > status.
could you help explain without clear the flag, how interrupt storming happen ?
as your change didn't touch any hardware register, i don't know how it fix storming.
storming from software layer ?
> So, It have to clean up DWC3_EVENT_PENDING flags set when count is 0. > It means "There are no interrupts to handle.". > > (struct dwc3_event_buffer *) ev_buf = 0xFFFFFF883DBF1180 ( > (void *) buf = 0xFFFFFFC00DBDD000 = end+0x337D000, > (void *) cache = 0xFFFFFF8839F54080, > (unsigned int) length = 0x1000, > (unsigned int) lpos = 0x0, > (unsigned int) count = 0x0, > (unsigned int) flags = 0x00000001, > (dma_addr_t) dma = 0x00000008BD7D7000, > (struct dwc3 *) dwc = 0xFFFFFF8839CBC880, > (u64) android_kabi_reserved1 = 0x0), > > (time = 47557628930999, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1), > (time = 47557628931268, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3), > (time = 47557628932383, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1), > (time = 47557628932652, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3), > (time = 47557628933768, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1), > (time = 47557628934037, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3), > (time = 47557628935152, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1), > (time = 47557628935460, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3), > (time = 47557628936575, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1), > (time = 47557628936845, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3), > (time = 47557628937960, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1), > (time = 47557628938229, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3), > (time = 47557628939345, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1), > (time = 47557628939652, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3), > (time = 47557628940768, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1), > (time = 47557628941037, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3), > (time = 47557628942152, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1), > (time = 47557628942422, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3), > (time = 47557628943537, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1), > (time = 47557628943806, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3), > (time = 47557628944922, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1), > (time = 47557628945229, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3), > (time = 47557628946345, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1), > (time = 47557628946614, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3), > (time = 47557628947729, irq = 165, fn = dwc3_interrupt, latency = 0, en = 1), > (time = 47557628947999, irq = 165, fn = dwc3_interrupt, latency = 0, en = 3), > > Signed-off-by: JaeHun Jung <jh0801.jung@samsung.com> > --- > drivers/usb/dwc3/gadget.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c > index 789976567f9f..5d2d5a9b9915 100644 > --- a/drivers/usb/dwc3/gadget.c > +++ b/drivers/usb/dwc3/gadget.c > @@ -4355,8 +4355,11 @@ static irqreturn_t dwc3_check_event_buf(struct dwc3_event_buffer *evt) > * irq event handler completes before caching new event to prevent > * losing events. > */ > - if (evt->flags & DWC3_EVENT_PENDING) > + if (evt->flags & DWC3_EVENT_PENDING) { > + if (!evt->count) > + evt->flags &= ~DWC3_EVENT_PENDING; > return IRQ_HANDLED; > + } > > count = dwc3_readl(dwc->regs, DWC3_GEVNTCOUNT(0)); > count &= DWC3_GEVNTCOUNT_MASK;
how about below change ?
count = dwc3_readl(dwc->regs, DWC3_GEVNTCOUNT(0)); count &= DWC3_GEVNTCOUNT_MASK; - if (!count) + if (!count) { + evt->flags &= ~DWC3_EVENT_PENDING; return IRQ_NONE; + }
evt->count = count; evt->flags |= DWC3_EVENT_PENDING;
| |