On 4 November 2016 at 07:41, Janusz Dziedzic <janusz.dziedzic@xxxxxxxxx> wrote: > On 4 November 2016 at 02:31, John Youn <johnyoun@xxxxxxxxxxxx> wrote: >> >> Since we are saving the event count and handling the events in the >> threaded interrupt handler, we can write and clear out the eventcount in >> the hard interrupt handler itself. >> >> This behavior will be required for IP 3.00a cores that need to use >> interrupt moderation as a workaround for an RTL issue were the interrupt >> line cannot be masked between the hard/soft interrupt handler. >> >> Signed-off-by: John Youn <johnyoun@xxxxxxxxxxxx> >> --- >> drivers/usb/dwc3/gadget.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c >> index a9c1d75..ac9eb39 100644 >> --- a/drivers/usb/dwc3/gadget.c >> +++ b/drivers/usb/dwc3/gadget.c >> @@ -2877,8 +2877,6 @@ static irqreturn_t dwc3_process_event_buf(struct dwc3_event_buffer *evt) >> */ >> evt->lpos = (evt->lpos + 4) % DWC3_EVENT_BUFFERS_SIZE; >> left -= 4; >> - >> - dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(0), 4); >> } >> >> evt->count = 0; >> @@ -2928,6 +2926,8 @@ static irqreturn_t dwc3_check_event_buf(struct dwc3_event_buffer *evt) >> evt->count = count; >> evt->flags |= DWC3_EVENT_PENDING; >> Shouldn't you cache (somewhere): u32 events[evt->buf + evt->lpos .... evt->buf + evt->lpos + count] before you will giveback this to HW (to be sure HW will not overwrite this in case lot of events)? >> + dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(0), count); >> + After that evt->buf[lpos, lpos + count] seems goes back to HW, so thread should not rely on this? Or I miss something? >> /* Mask interrupt */ >> reg = dwc3_readl(dwc->regs, DWC3_GEVNTSIZ(0)); >> reg |= DWC3_GEVNTSIZ_INTMASK; >> -- > > Hello, > > Are we sure this will work fine with 2.60a? > > Some time ago I have similar code (introduce event_pop) and move > dwc3_write(dwc->regs, DWC3_GEVNTCOUNT(0), 4) > before > dwc3_process_event_entry() > > And have some issues ... > Didn't work correctly in my case. > > BR > Janusz -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
