Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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 <niklas.neronin@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://patch.msgid.link/20260402131342.2628648-13-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
authored by
Niklas Neronin
and committed by
Greg Kroah-Hartman
2a70e5dc
951564d2
+35
-24
+2
-2
drivers/usb/host/xhci-mem.c
+2
-2
drivers/usb/host/xhci-mem.c
···
936
936
* that tt_info, then free the child first. Recursive.
937
937
* We can't rely on udev at this point to find child-parent relationships.
938
938
*/
939
-
static void xhci_free_virt_devices_depth_first(struct xhci_hcd *xhci, int slot_id)
939
+
void xhci_free_virt_devices_depth_first(struct xhci_hcd *xhci, int slot_id)
940
940
{
941
941
struct xhci_virt_device *vdev;
942
942
struct list_head *tt_list_head;
···
1905
1905
EXPORT_SYMBOL_GPL(xhci_remove_secondary_interrupter);
1906
1906
1907
1907
/* Cleanup roothub bandwidth data */
1908
-
static void xhci_rh_bw_cleanup(struct xhci_hcd *xhci)
1908
+
void xhci_rh_bw_cleanup(struct xhci_hcd *xhci)
1909
1909
{
1910
1910
struct xhci_root_port_bw_info *rh_bw;
1911
1911
struct xhci_tt_bw_info *tt_info, *tt_next;
+31
-22
drivers/usb/host/xhci.c
+31
-22
drivers/usb/host/xhci.c
···
1082
1082
{
1083
1083
u32 command, temp = 0;
1084
1084
struct usb_hcd *hcd = xhci_to_hcd(xhci);
1085
+
struct xhci_segment *seg;
1085
1086
int retval = 0;
1086
1087
bool pending_portevent = false;
1087
1088
bool suspended_usb3_devs = false;
1089
+
bool reset_registers = false;
1088
1090
1089
1091
if (!hcd->state)
1090
1092
return 0;
···
1105
1103
1106
1104
spin_lock_irq(&xhci->lock);
1107
1105
1108
-
if (xhci->quirks & XHCI_RESET_ON_RESUME || xhci->broken_suspend)
1109
-
power_lost = true;
1110
-
1111
-
if (!power_lost) {
1106
+
if (power_lost || xhci->broken_suspend || xhci->quirks & XHCI_RESET_ON_RESUME) {
1107
+
xhci_dbg(xhci, "HC state lost, performing host controller reset\n");
1108
+
reset_registers = true;
1109
+
} else {
1110
+
xhci_dbg(xhci, "HC state intact, continuing without reset\n");
1112
1111
/*
1113
1112
* Some controllers might lose power during suspend, so wait
1114
1113
* for controller not ready bit to clear, just as in xHC init.
···
1147
1144
temp = readl(&xhci->op_regs->status);
1148
1145
if ((temp & (STS_SRE | STS_HCE)) && !(xhci->xhc_state & XHCI_STATE_REMOVING)) {
1149
1146
xhci_warn(xhci, "xHC error in resume, USBSTS 0x%x, Reinit\n", temp);
1150
-
power_lost = true;
1147
+
reset_registers = true;
1151
1148
}
1152
1149
}
1153
1150
1154
-
if (power_lost) {
1151
+
if (reset_registers) {
1155
1152
if ((xhci->quirks & XHCI_COMP_MODE_QUIRK) &&
1156
1153
!(xhci_all_ports_seen_u0(xhci))) {
1157
1154
timer_delete_sync(&xhci->comp_mode_recovery_timer);
···
1175
1172
if (retval)
1176
1173
return retval;
1177
1174
1178
-
xhci_dbg(xhci, "// Disabling event ring interrupts\n");
1179
-
temp = readl(&xhci->op_regs->status);
1180
-
writel((temp & ~0x1fff) | STS_EINT, &xhci->op_regs->status);
1181
-
xhci_disable_interrupter(xhci, xhci->interrupters[0]);
1175
+
cancel_delayed_work_sync(&xhci->cmd_timer);
1182
1176
1183
-
xhci_dbg(xhci, "cleaning up memory\n");
1184
-
xhci_mem_cleanup(xhci);
1177
+
/* Delete all remaining commands */
1178
+
xhci_cleanup_command_queue(xhci);
1179
+
1180
+
/* Clear data which is re-initilized during runtime */
1181
+
xhci_for_each_ring_seg(xhci->interrupters[0]->event_ring->first_seg, seg)
1182
+
memset(seg->trbs, 0, sizeof(union xhci_trb) * TRBS_PER_SEGMENT);
1183
+
1184
+
for (int i = xhci->max_slots; i > 0; i--)
1185
+
xhci_free_virt_devices_depth_first(xhci, i);
1186
+
1187
+
xhci_rh_bw_cleanup(xhci);
1188
+
1189
+
xhci->cmd_ring_reserved_trbs = 0;
1190
+
xhci_for_each_ring_seg(xhci->cmd_ring->first_seg, seg)
1191
+
memset(seg->trbs, 0, sizeof(union xhci_trb) * TRBS_PER_SEGMENT);
1192
+
1185
1193
xhci_debugfs_exit(xhci);
1186
-
xhci_dbg(xhci, "xhci_stop completed - status = %x\n",
1187
-
readl(&xhci->op_regs->status));
1188
-
1189
-
/* USB core calls the PCI reinit and start functions twice:
1190
-
* first with the primary HCD, and then with the secondary HCD.
1191
-
* If we don't do the same, the host will never be started.
1192
-
*/
1193
-
retval = xhci_mem_init(xhci, GFP_KERNEL);
1194
-
if (retval)
1195
-
return retval;
1196
1194
1197
1195
xhci_init(hcd);
1198
1196
1197
+
/*
1198
+
* USB core calls the PCI reinit and start functions twice:
1199
+
* first with the primary HCD, and then with the secondary HCD.
1200
+
* If we don't do the same, the host will never be started.
1201
+
*/
1199
1202
xhci_dbg(xhci, "Start the primary HCD\n");
1200
1203
retval = xhci_run(hcd);
1201
1204
if (!retval && xhci->shared_hcd) {
+2
drivers/usb/host/xhci.h
+2
drivers/usb/host/xhci.h
···
1793
1793
void xhci_mem_cleanup(struct xhci_hcd *xhci);
1794
1794
int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags);
1795
1795
void xhci_free_virt_device(struct xhci_hcd *xhci, struct xhci_virt_device *dev, int slot_id);
1796
+
void xhci_free_virt_devices_depth_first(struct xhci_hcd *xhci, int slot_id);
1796
1797
int xhci_alloc_virt_device(struct xhci_hcd *xhci, int slot_id, struct usb_device *udev, gfp_t flags);
1797
1798
int xhci_setup_addressable_virt_dev(struct xhci_hcd *xhci, struct usb_device *udev);
1798
1799
void xhci_copy_ep0_dequeue_into_input_ctx(struct xhci_hcd *xhci,
···
1805
1804
struct xhci_virt_device *virt_dev,
1806
1805
int old_active_eps);
1807
1806
void xhci_clear_endpoint_bw_info(struct xhci_bw_info *bw_info);
1807
+
void xhci_rh_bw_cleanup(struct xhci_hcd *xhci);
1808
1808
void xhci_update_bw_info(struct xhci_hcd *xhci,
1809
1809
struct xhci_container_ctx *in_ctx,
1810
1810
struct xhci_input_control_ctx *ctrl_ctx,