This is a note to let you know that I've just added the patch titled usb: dwc3: host: Set XHCI_SG_TRB_CACHE_SIZE_QUIRK to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: usb-dwc3-host-set-xhci_sg_trb_cache_size_quirk.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 817349b6d26aadd8b38283a05ce0bab106b4c765 Mon Sep 17 00:00:00 2001 From: Prashanth K <quic_prashk@xxxxxxxxxxx> Date: Tue, 16 Jan 2024 11:28:15 +0530 Subject: usb: dwc3: host: Set XHCI_SG_TRB_CACHE_SIZE_QUIRK From: Prashanth K <quic_prashk@xxxxxxxxxxx> commit 817349b6d26aadd8b38283a05ce0bab106b4c765 upstream. Upstream commit bac1ec551434 ("usb: xhci: Set quirk for XHCI_SG_TRB_CACHE_SIZE_QUIRK") introduced a new quirk in XHCI which fixes XHC timeout, which was seen on synopsys XHCs while using SG buffers. But the support for this quirk isn't present in the DWC3 layer. We will encounter this XHCI timeout/hung issue if we run iperf loopback tests using RTL8156 ethernet adaptor on DWC3 targets with scatter-gather enabled. This gets resolved after enabling the XHCI_SG_TRB_CACHE_SIZE_QUIRK. This patch enables it using the xhci device property since its needed for DWC3 controller. In Synopsys DWC3 databook, Table 9-3: xHCI Debug Capability Limitations Chained TRBs greater than TRB cache size: The debug capability driver must not create a multi-TRB TD that describes smaller than a 1K packet that spreads across 8 or more TRBs on either the IN TR or the OUT TR. Cc: stable@xxxxxxxxxxxxxxx #5.11 Signed-off-by: Prashanth K <quic_prashk@xxxxxxxxxxx> Acked-by: Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx> Link: https://lore.kernel.org/r/20240116055816.1169821-2-quic_prashk@xxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/dwc3/host.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/usb/dwc3/host.c +++ b/drivers/usb/dwc3/host.c @@ -44,7 +44,7 @@ out: int dwc3_host_init(struct dwc3 *dwc) { - struct property_entry props[4]; + struct property_entry props[5]; struct platform_device *xhci; int ret, irq; struct resource *res; @@ -89,6 +89,8 @@ int dwc3_host_init(struct dwc3 *dwc) memset(props, 0, sizeof(struct property_entry) * ARRAY_SIZE(props)); + props[prop_idx++] = PROPERTY_ENTRY_BOOL("xhci-sg-trb-cache-size-quirk"); + if (dwc->usb3_lpm_capable) props[prop_idx++] = PROPERTY_ENTRY_BOOL("usb3-lpm-capable"); Patches currently in stable-queue which might be from quic_prashk@xxxxxxxxxxx are queue-5.15/usb-host-xhci-plat-add-support-for-xhci_sg_trb_cache_size_quirk.patch queue-5.15/usb-dwc3-host-set-xhci_sg_trb_cache_size_quirk.patch