Hi,
I've not fully implemented and tested this yet, I just wanted to make sure I was on the right track as far as what to modify in the xhci_hcd module to limit bInterval for super speed endpoints.
With the TI USB3 host controllers we have found that there is an intermittent enumeration issue with devices whose interrupt EP binterval >7. As a result the xHCI Driver should program binterval = 7 for any device reporting binterval > 7 on the interrupt EP.
I'm putting the clamping of bInterval in xhci_endpoint_init, but am not sure if this is the correct location.
Patch follows.
Sincerely,
Dwight Schauer
Texas Instruments, Inc.
#### Start Patch
diff -wubr host.0/xhci.h host/xhci.h
--- host.0/xhci.h 2011-06-23 17:06:00.000000000 -0500
+++ host/xhci.h 2011-06-29 17:27:50.968159616 -0500
@@ -1287,6 +1287,7 @@
#define XHCI_NEC_HOST (1 << 2)
#define XHCI_AMD_PLL_FIX (1 << 3)
#define XHCI_BROKEN_MSI (1 << 6)
+#define XHCI_TI_HOST (1 << 7)
/* There are two roothubs to keep track of bus suspend info for */
struct xhci_bus_state bus_state[2];
/* Is each xHCI roothub port a USB 3.0, USB 2.0, or USB 1.1 port? */
diff -wubr host.0/xhci-mem.c host/xhci-mem.c
--- host.0/xhci-mem.c 2011-06-30 09:01:38.137040233 -0500
+++ host/xhci-mem.c 2011-06-30 09:02:50.903555788 -0500
@@ -1195,6 +1195,11 @@
ep_ctx->deq = ep_ring->first_seg->dma | ep_ring->cycle_state;
ep_ctx->ep_info = xhci_get_endpoint_interval(udev, ep);
+
+ if ((udev->speed == USB_SPEED_SUPER) && (xhci->quirks & XHCI_TI_HOST)) {
+ ep_ctx->ep_info = clamp_val (ep_ctx->ep_info, 1, 7);
+ }
+
ep_ctx->ep_info |= EP_MULT(xhci_get_endpoint_mult(udev, ep));
/* FIXME dig Mult and streams info out of ep companion desc */
diff -wubr host.0/xhci-pci.c host/xhci-pci.c
--- host.0/xhci-pci.c 2011-06-23 17:06:00.000000000 -0500
+++ host/xhci-pci.c 2011-06-29 17:28:47.494708634 -0500
@@ -124,6 +124,9 @@
if (pdev->vendor == PCI_VENDOR_ID_NEC)
xhci->quirks |= XHCI_NEC_HOST;
+ if (pdev->vendor == PCI_VENDOR_ID_TI)
+ xhci->quirks |= XHCI_TI_HOST;
+
/* AMD PLL quirk */
if (pdev->vendor == PCI_VENDOR_ID_AMD && usb_amd_find_chipset_info())
xhci->quirks |= XHCI_AMD_PLL_FIX;
#### End Patch
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