From: Niklas Neronin Date: Thu, 2 Apr 2026 13:13:29 +0000 (+0300) Subject: usb: xhci: optimize resuming from S4 (suspend-to-disk) X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2a70e5dc0301ad961b198f086a39e2479f6b8933;p=thirdparty%2Flinux.git usb: xhci: optimize resuming from S4 (suspend-to-disk) On resume from S4 (power loss after suspend/hibernation), the xHCI driver previously freed, reallocated, and fully reinitialized all data structures. Most of this is unnecessary because the data is restored from a saved image; only the xHCI registers lose their values. This patch optimizes S4 resume by performing only a host controller reset, which includes: * Freeing or clearing runtime-created data. * Rewriting xHCI registers. Signed-off-by: Niklas Neronin Signed-off-by: Mathias Nyman Link: https://patch.msgid.link/20260402131342.2628648-13-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c index f1b4f06d4b8b..4156822eb000 100644 --- a/drivers/usb/host/xhci-mem.c +++ b/drivers/usb/host/xhci-mem.c @@ -936,7 +936,7 @@ void xhci_free_virt_device(struct xhci_hcd *xhci, struct xhci_virt_device *dev, * that tt_info, then free the child first. Recursive. * We can't rely on udev at this point to find child-parent relationships. */ -static void xhci_free_virt_devices_depth_first(struct xhci_hcd *xhci, int slot_id) +void xhci_free_virt_devices_depth_first(struct xhci_hcd *xhci, int slot_id) { struct xhci_virt_device *vdev; struct list_head *tt_list_head; @@ -1905,7 +1905,7 @@ void xhci_remove_secondary_interrupter(struct usb_hcd *hcd, struct xhci_interrup EXPORT_SYMBOL_GPL(xhci_remove_secondary_interrupter); /* Cleanup roothub bandwidth data */ -static void xhci_rh_bw_cleanup(struct xhci_hcd *xhci) +void xhci_rh_bw_cleanup(struct xhci_hcd *xhci) { struct xhci_root_port_bw_info *rh_bw; struct xhci_tt_bw_info *tt_info, *tt_next; diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 2c573aad4464..ece3ff7916ff 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -1082,9 +1082,11 @@ int xhci_resume(struct xhci_hcd *xhci, bool power_lost, bool is_auto_resume) { u32 command, temp = 0; struct usb_hcd *hcd = xhci_to_hcd(xhci); + struct xhci_segment *seg; int retval = 0; bool pending_portevent = false; bool suspended_usb3_devs = false; + bool reset_registers = false; if (!hcd->state) return 0; @@ -1103,10 +1105,11 @@ int xhci_resume(struct xhci_hcd *xhci, bool power_lost, bool is_auto_resume) spin_lock_irq(&xhci->lock); - if (xhci->quirks & XHCI_RESET_ON_RESUME || xhci->broken_suspend) - power_lost = true; - - if (!power_lost) { + if (power_lost || xhci->broken_suspend || xhci->quirks & XHCI_RESET_ON_RESUME) { + xhci_dbg(xhci, "HC state lost, performing host controller reset\n"); + reset_registers = true; + } else { + xhci_dbg(xhci, "HC state intact, continuing without reset\n"); /* * Some controllers might lose power during suspend, so wait * for controller not ready bit to clear, just as in xHC init. @@ -1144,11 +1147,11 @@ int xhci_resume(struct xhci_hcd *xhci, bool power_lost, bool is_auto_resume) temp = readl(&xhci->op_regs->status); if ((temp & (STS_SRE | STS_HCE)) && !(xhci->xhc_state & XHCI_STATE_REMOVING)) { xhci_warn(xhci, "xHC error in resume, USBSTS 0x%x, Reinit\n", temp); - power_lost = true; + reset_registers = true; } } - if (power_lost) { + if (reset_registers) { if ((xhci->quirks & XHCI_COMP_MODE_QUIRK) && !(xhci_all_ports_seen_u0(xhci))) { timer_delete_sync(&xhci->comp_mode_recovery_timer); @@ -1172,27 +1175,33 @@ int xhci_resume(struct xhci_hcd *xhci, bool power_lost, bool is_auto_resume) if (retval) return retval; - xhci_dbg(xhci, "// Disabling event ring interrupts\n"); - temp = readl(&xhci->op_regs->status); - writel((temp & ~0x1fff) | STS_EINT, &xhci->op_regs->status); - xhci_disable_interrupter(xhci, xhci->interrupters[0]); + cancel_delayed_work_sync(&xhci->cmd_timer); + + /* Delete all remaining commands */ + xhci_cleanup_command_queue(xhci); + + /* Clear data which is re-initilized during runtime */ + xhci_for_each_ring_seg(xhci->interrupters[0]->event_ring->first_seg, seg) + memset(seg->trbs, 0, sizeof(union xhci_trb) * TRBS_PER_SEGMENT); + + for (int i = xhci->max_slots; i > 0; i--) + xhci_free_virt_devices_depth_first(xhci, i); + + xhci_rh_bw_cleanup(xhci); + + xhci->cmd_ring_reserved_trbs = 0; + xhci_for_each_ring_seg(xhci->cmd_ring->first_seg, seg) + memset(seg->trbs, 0, sizeof(union xhci_trb) * TRBS_PER_SEGMENT); - xhci_dbg(xhci, "cleaning up memory\n"); - xhci_mem_cleanup(xhci); xhci_debugfs_exit(xhci); - xhci_dbg(xhci, "xhci_stop completed - status = %x\n", - readl(&xhci->op_regs->status)); - /* USB core calls the PCI reinit and start functions twice: + xhci_init(hcd); + + /* + * USB core calls the PCI reinit and start functions twice: * first with the primary HCD, and then with the secondary HCD. * If we don't do the same, the host will never be started. */ - retval = xhci_mem_init(xhci, GFP_KERNEL); - if (retval) - return retval; - - xhci_init(hcd); - xhci_dbg(xhci, "Start the primary HCD\n"); retval = xhci_run(hcd); if (!retval && xhci->shared_hcd) { diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h index 06f6da4d982f..aeecd301f207 100644 --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -1793,6 +1793,7 @@ void xhci_dbg_trace(struct xhci_hcd *xhci, void (*trace)(struct va_format *), void xhci_mem_cleanup(struct xhci_hcd *xhci); int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags); void xhci_free_virt_device(struct xhci_hcd *xhci, struct xhci_virt_device *dev, int slot_id); +void xhci_free_virt_devices_depth_first(struct xhci_hcd *xhci, int slot_id); int xhci_alloc_virt_device(struct xhci_hcd *xhci, int slot_id, struct usb_device *udev, gfp_t flags); int xhci_setup_addressable_virt_dev(struct xhci_hcd *xhci, struct usb_device *udev); void xhci_copy_ep0_dequeue_into_input_ctx(struct xhci_hcd *xhci, @@ -1804,6 +1805,7 @@ void xhci_update_tt_active_eps(struct xhci_hcd *xhci, struct xhci_virt_device *virt_dev, int old_active_eps); void xhci_clear_endpoint_bw_info(struct xhci_bw_info *bw_info); +void xhci_rh_bw_cleanup(struct xhci_hcd *xhci); void xhci_update_bw_info(struct xhci_hcd *xhci, struct xhci_container_ctx *in_ctx, struct xhci_input_control_ctx *ctrl_ctx,