[xhci] Increase link state settling delay to 100ms

Experimentation shows that the existing 20ms delay is insufficient,
and often results in device detection being deferred until after iPXE
has completed startup.

Fix by increasing the delay to 100ms.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

diff --git a/src/drivers/usb/xhci.h b/src/drivers/usb/xhci.h
index 83bf71e7e37791d2f347e90ab7c31427ce3adb65..e996363eac24920e268ca62464fd23e9ecbf9b4a 100644 (file)
--- a/src/drivers/usb/xhci.h
+++ b/src/drivers/usb/xhci.h
@@ -243,7 +243,7 @@ enum xhci_default_psi_value {
 #define XHCI_PORTSC_LWS 0x00010000UL
 
 /** Time to delay after writing the port link state */
-#define XHCI_LINK_STATE_DELAY_MS 20
+#define XHCI_LINK_STATE_DELAY_MS 100
 
 /** Connect status change */
 #define XHCI_PORTSC_CSC 0x00020000UL