From patchwork Tue Aug 15 12:40:37 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukas Wunner X-Patchwork-Id: 714004 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 00F49C001B0 for ; Tue, 15 Aug 2023 12:41:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235048AbjHOMlV (ORCPT ); Tue, 15 Aug 2023 08:41:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56356 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237279AbjHOMlF (ORCPT ); Tue, 15 Aug 2023 08:41:05 -0400 Received: from bmailout3.hostsharing.net (bmailout3.hostsharing.net [176.9.242.62]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CCDC2F7 for ; Tue, 15 Aug 2023 05:40:42 -0700 (PDT) Received: from h08.hostsharing.net (h08.hostsharing.net [83.223.95.28]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "*.hostsharing.net", Issuer "RapidSSL Global TLS RSA4096 SHA256 2022 CA1" (verified OK)) by bmailout3.hostsharing.net (Postfix) with ESMTPS id E001D100D943A; Tue, 15 Aug 2023 14:40:40 +0200 (CEST) Received: by h08.hostsharing.net (Postfix, from userid 100393) id B4F282ED5CA; Tue, 15 Aug 2023 14:40:40 +0200 (CEST) Message-Id: From: Lukas Wunner Date: Tue, 15 Aug 2023 14:40:37 +0200 Subject: [PATCH 0/2] Multi-segment Event Ring support for XHCI To: Mathias Nyman , Greg Kroah-Hartman Cc: linux-usb@vger.kernel.org, Jonathan Bell , Phil Elwell , Nicolas Saenz Julienne , Stefan Wahren , Philipp Rosenberger , Lino Sanfilippo Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Enlarge the XHCI Event Ring to cope with high load situations by allowing more than one segment (patch [2/2]). The patch is lifted from the Raspberry Pi kernel, it has been in use there for 4 years. I've taken the liberty to slightly edit the commit message and the patch itself for upstream. As a prerequisite for the patch, ensure that the DESI bits in the ERDP register are set correctly (patch [1/2]). Incorrect DESI bits cause an interrupt storm on Renesas uPD720201 host controllers. Jonathan Bell (1): xhci: Use more than one Event Ring segment Lukas Wunner (1): xhci: Set DESI bits in ERDP register correctly drivers/usb/host/xhci-mem.c | 35 ++++++++++++++++++----------------- drivers/usb/host/xhci-ring.c | 2 +- drivers/usb/host/xhci.h | 6 ++++-- 3 files changed, 23 insertions(+), 20 deletions(-)