This is a note to let you know that I've just added the patch titled xhci: move event processing for one interrupter to a separate function to the 6.8-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: xhci-move-event-processing-for-one-interrupter-to-a-.patch and it can be found in the queue-6.8 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit a48cb7d64ed88bb3eacb9bd5485e7e432d173896 Author: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx> Date: Fri Feb 16 16:09:32 2024 -0800 xhci: move event processing for one interrupter to a separate function [ Upstream commit 84ac5e4fa517f5d1da0054547a82ce905678dc08 ] Split the main XHCI interrupt handler into a different API, so that other potential interrupters can utilize similar event ring handling. A scenario would be if a secondary interrupter required to skip pending events in the event ring, which would warrant a similar set of operations. Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx> Signed-off-by: Wesley Cheng <quic_wcheng@xxxxxxxxxxx> Link: https://lore.kernel.org/r/20240217001017.29969-7-quic_wcheng@xxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Stable-dep-of: 5bfc311dd6c3 ("usb: xhci: correct return value in case of STS_HCE") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index 61bd29dd71a2f..2306a95d6251a 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -3075,6 +3075,46 @@ static void xhci_clear_interrupt_pending(struct xhci_hcd *xhci, } } +static int xhci_handle_events(struct xhci_hcd *xhci, struct xhci_interrupter *ir) +{ + int event_loop = 0; + u64 temp; + + xhci_clear_interrupt_pending(xhci, ir); + + if (xhci->xhc_state & XHCI_STATE_DYING || + xhci->xhc_state & XHCI_STATE_HALTED) { + xhci_dbg(xhci, "xHCI dying, ignoring interrupt. Shouldn't IRQs be disabled?\n"); + + /* Clear the event handler busy flag (RW1C) */ + temp = xhci_read_64(xhci, &ir->ir_set->erst_dequeue); + xhci_write_64(xhci, temp | ERST_EHB, &ir->ir_set->erst_dequeue); + return -ENODEV; + } + + while (xhci_handle_event(xhci, ir) > 0) { + /* + * If half a segment of events have been handled in one go then + * update ERDP, and force isoc trbs to interrupt more often + */ + if (event_loop++ > TRBS_PER_SEGMENT / 2) { + xhci_update_erst_dequeue(xhci, ir, false); + + if (ir->isoc_bei_interval > AVOID_BEI_INTERVAL_MIN) + ir->isoc_bei_interval = ir->isoc_bei_interval / 2; + + event_loop = 0; + } + + /* Update SW event ring dequeue pointer */ + inc_deq(xhci, ir->event_ring); + } + + xhci_update_erst_dequeue(xhci, ir, true); + + return 0; +} + /* * xHCI spec says we can get an interrupt, and if the HC has an error condition, * we might get bad data out of the event ring. Section 4.10.2.7 has a list of @@ -3083,11 +3123,8 @@ static void xhci_clear_interrupt_pending(struct xhci_hcd *xhci, irqreturn_t xhci_irq(struct usb_hcd *hcd) { struct xhci_hcd *xhci = hcd_to_xhci(hcd); - struct xhci_interrupter *ir; irqreturn_t ret = IRQ_NONE; - u64 temp_64; u32 status; - int event_loop = 0; spin_lock(&xhci->lock); /* Check if the xHC generated the interrupt, or the irq is shared */ @@ -3120,50 +3157,10 @@ irqreturn_t xhci_irq(struct usb_hcd *hcd) */ status |= STS_EINT; writel(status, &xhci->op_regs->status); - - /* This is the handler of the primary interrupter */ - ir = xhci->interrupters[0]; - - xhci_clear_interrupt_pending(xhci, ir); - - if (xhci->xhc_state & XHCI_STATE_DYING || - xhci->xhc_state & XHCI_STATE_HALTED) { - xhci_dbg(xhci, "xHCI dying, ignoring interrupt. " - "Shouldn't IRQs be disabled?\n"); - /* Clear the event handler busy flag (RW1C); - * the event ring should be empty. - */ - temp_64 = xhci_read_64(xhci, &ir->ir_set->erst_dequeue); - xhci_write_64(xhci, temp_64 | ERST_EHB, - &ir->ir_set->erst_dequeue); - ret = IRQ_HANDLED; - goto out; - } - - /* FIXME this should be a delayed service routine - * that clears the EHB. - */ - while (xhci_handle_event(xhci, ir) > 0) { - /* - * If half a segment of events have been handled in one go then - * update ERDP, and force isoc trbs to interrupt more often - */ - if (event_loop++ > TRBS_PER_SEGMENT / 2) { - xhci_update_erst_dequeue(xhci, ir, false); - - if (ir->isoc_bei_interval > AVOID_BEI_INTERVAL_MIN) - ir->isoc_bei_interval = ir->isoc_bei_interval / 2; - - event_loop = 0; - } - - /* Update SW event ring dequeue pointer */ - inc_deq(xhci, ir->event_ring); - } - - xhci_update_erst_dequeue(xhci, ir, true); ret = IRQ_HANDLED; + /* This is the handler of the primary interrupter */ + xhci_handle_events(xhci, xhci->interrupters[0]); out: spin_unlock(&xhci->lock);