[SeaBIOS] [PATCH] xhci: Wait for port enable even for USB3 devices

[Kevin O'Connor]

Some USB3 controllers (and/or devices) need additional time after the
device is detected to place the port in an enabled state.  Wait for
the controller to report enabled before proceeding.  This fixes
several reports of devices that showed a "stall" error (cc 4) during
set address.

Signed-off-by: Kevin O'Connor 
---
 src/hw/usb-xhci.c | 43 +++++++++++++++++++++----------------------
 1 file changed, 21 insertions(+), 22 deletions(-)

diff --git a/src/hw/usb-xhci.c b/src/hw/usb-xhci.c
index 945b462..654feba 100644
--- a/src/hw/usb-xhci.c
+++ b/src/hw/usb-xhci.c
@@ -350,42 +350,41 @@ xhci_hub_reset(struct usbhub_s *hub, u32 port)
 {
     struct usb_xhci_s *xhci = container_of(hub->cntl, struct usb_xhci_s, usb);
     u32 portsc = readl(&xhci->pr[port].portsc);
-    int rc;
     if (!(portsc & XHCI_PORTSC_CCS))
         // Device no longer connected?!
         return -1;

switch (xhci_get_field(portsc, XHCI_PORTSC_PLS)) {
     case PLS_U0:
-        // A USB3 port - no reset necessary.
-        rc = speed_from_xhci[xhci_get_field(portsc, XHCI_PORTSC_SPEED)];
+        // A USB3 port - controller automatically performs reset
         break;
     case PLS_POLLING:
-        // A USB2 port - perform device reset and wait for completion
+        // A USB2 port - perform device reset
         xhci_print_port_state(3, __func__, port, portsc);
         writel(&xhci->pr[port].portsc, portsc | XHCI_PORTSC_PR);
-        u32 end = timer_calc(100);
-        for (;;) {
-            portsc = readl(&xhci->pr[port].portsc);
-            if (!(portsc & XHCI_PORTSC_CCS))
-                // Device disconnected during reset
-                return -1;
-            if (portsc & XHCI_PORTSC_PED)
-                // Reset complete
-                break;
-            if (timer_check(end)) {
-                warn_timeout();
-                return -1;
-            }
-            yield();
-        }
-        rc = speed_from_xhci[xhci_get_field(portsc, XHCI_PORTSC_SPEED)];
         break;
     default:
-        rc = -1;
-        break;
+        return -1;
+    }
+
+    // Wait for device to complete reset and be enabled
+    u32 end = timer_calc(100);
+    for (;;) {
+        portsc = readl(&xhci->pr[port].portsc);
+        if (!(portsc & XHCI_PORTSC_CCS))
+            // Device disconnected during reset
+            return -1;
+        if (portsc & XHCI_PORTSC_PED)
+            // Reset complete
+            break;
+        if (timer_check(end)) {
+            warn_timeout();
+            return -1;
+        }
+        yield();
     }

+    int rc = speed_from_xhci[xhci_get_field(portsc, XHCI_PORTSC_SPEED)];
     xhci_print_port_state(1, "XHCI", port, portsc);
     return rc;
 }