From patchwork Thu May 15 18:52:26 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roy Luo X-Patchwork-Id: 890865 Received: from mail-ua1-f74.google.com (mail-ua1-f74.google.com [209.85.222.74]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 23BAB26982D for ; Thu, 15 May 2025 18:52:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.222.74 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747335164; cv=none; b=Baac6qG1jrWLf8d44VLH9mZSvo86oCuB4FEpLNp4IDixgX7T5VPXr51P6kFObhmS5o7jwlUby1w1y5wvjaqWKEK9OA+lbgb2qKr51jS9sk/qh9SLL6Znv8e4pnnOxQSqhhqOGG/AvfakE3TR94ZE/H7YHvPkUCihqZdVQ/rVn4I= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747335164; c=relaxed/simple; bh=K63IL0wd/AKdNf65nemBDPL4UNxLf79dzeti/LRO/dc=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=N7I+l6IKnznrvY1WuMzwZTzY1GAQlDq4loBZ+8qOx+ttUeh2BFV1GID4vQ95gV6ZwkyrfCJKW9IF8n8/Io/X1VdUywfzxFnHS7X3xhIhWUL4r6QKmaNfcQqe4TdlX2PbgHIHBaDjuWtdeD0nTHYsWGLBHR1sBdtm8yiragKunS8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--royluo.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=RLas4Hmf; arc=none smtp.client-ip=209.85.222.74 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--royluo.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="RLas4Hmf" Received: by mail-ua1-f74.google.com with SMTP id a1e0cc1a2514c-8784474f080so939719241.1 for ; Thu, 15 May 2025 11:52:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1747335162; x=1747939962; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=tL75l/1ix6yb8tbp2dmZra7s66c/0nxAmQo/67QfY1c=; b=RLas4HmfZdBgXec0iVl9utjTrnZwrjBuxziIyXoYb9G5IBY5hNXLf7WqvI9MCWSCNs 6Oj4PoTdn6RCgs2eILDJD5DbnUC0k11WkeeK99oQdR0Uqbigz4adZ7CvWBj5JOVsD0fN 6aL1sKGDSwdmOeF1bhb0PYf+StEZTAeRM94yX4UpUWQ4E80oTV8ydrc0a/tGyEeVoV7P W6fQ09nwugMXQIgokTvofz8OUx1nAJAZd7LIaaibsJ+qYp4tdZeU7SLPa/BEODozD3CE bv3n3tIQfgWcR1BTMRZCmi4Rshzz7yutYedXREuyCT21JkJqZdJWPsYC3KoJoF0oI8oU LJhg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1747335162; x=1747939962; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=tL75l/1ix6yb8tbp2dmZra7s66c/0nxAmQo/67QfY1c=; b=sHJyNNoOqQdczQ0ECOWOIEs9JoKYWy1csJSof5kbSEuMbFZ0vR5qT9skhmPhJPpLm8 xCRT8fQzuAzyKQcpJ/n3VGqCG21HzV/bwuCVFDeCzoaMfRUEiALfCyWOX1fLwNOH3GWl grmZ1zRTpvAraWrizDTfSa204kHjFUORu3o8tVG9v5YwwoD8tgvusUBJqpWLByiH4+sb a4GYHsnhJ/yqhWtYY1l1DB5KL+qOqWJZmBAEdshvp0mTOCVSSPUeBpcsXP1LGPVj24u5 VJX812lXtf5dtAKxGgrDwvEPZv7xkjbPztvSqi+1iYiTD4OROE2wSPpjvRJ0RVReeeMy hwSw== X-Forwarded-Encrypted: i=1; AJvYcCU4LADbeZ+ljzM+im/oA8GmzLgud6OCa+oyXBLcuTuWsVPyuAxwYE6nx6mfKxQz2yA85EtxotyL3AY=@vger.kernel.org X-Gm-Message-State: AOJu0YxFv3403/0o15g6fMDw9avPBJXuGsTpo63CQdqSNF4dxCV60EEa GdHDgOUvlS/gGbZDuL9VXnn1ZZkvCH0xIr0FMxQ3zOtf0BlxDUoeAJm5GYpipYWqwu1fMICZRmn 5Rw0eVw== X-Google-Smtp-Source: AGHT+IHwuQNwb0vPJPmRY4g+OzhIySpP7oIxTudeED3uvgNH9M4u5I7QlZs6oj9hjEmhqlFSDJT1BU6HPfA= X-Received: from uabjd12.prod.google.com ([2002:a05:6130:678c:b0:879:ee02:ddc8]) (user=royluo job=prod-delivery.src-stubby-dispatcher) by 2002:a67:ff90:0:b0:4db:10bf:6f2c with SMTP id ada2fe7eead31-4df900f5181mr5384781137.11.1747335161968; Thu, 15 May 2025 11:52:41 -0700 (PDT) Date: Thu, 15 May 2025 18:52:26 +0000 In-Reply-To: <20250515185227.1507363-1-royluo@google.com> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250515185227.1507363-1-royluo@google.com> X-Mailer: git-send-email 2.49.0.1112.g889b7c5bd8-goog Message-ID: <20250515185227.1507363-2-royluo@google.com> Subject: [PATCH v2 1/2] xhci: Add a quirk for full reset on removal From: Roy Luo To: royluo@google.com, mathias.nyman@intel.com, quic_ugoswami@quicinc.com, Thinh.Nguyen@synopsys.com, gregkh@linuxfoundation.org, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org Commit 6ccb83d6c497 ("usb: xhci: Implement xhci_handshake_check_state() helper") introduced an optimization to xhci_reset() during xhci removal, allowing it to bail out early without waiting for the reset to complete. This behavior can cause issues on SNPS DWC3 USB controller with dual-role capability. When the DWC3 controller exits host mode and removes xhci while a reset is still in progress, and then tries to configure its hardware for device mode, the ongoing reset leads to register access issues; specifically, all register reads returns 0. These issues extend beyond the xhci register space (which is expected during a reset) and affect the entire DWC3 IP block, causing the DWC3 device mode to malfunction. To address this, introduce the `XHCI_FULL_RESET_ON_REMOVE` quirk. When this quirk is set, xhci_reset() always completes its reset handshake, ensuring the controller is in a fully reset state before proceeding. Cc: stable@vger.kernel.org Fixes: 6ccb83d6c497 ("usb: xhci: Implement xhci_handshake_check_state() helper") Signed-off-by: Roy Luo --- drivers/usb/host/xhci-plat.c | 3 +++ drivers/usb/host/xhci.c | 8 +++++++- drivers/usb/host/xhci.h | 1 + 3 files changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c index 3155e3a842da..19c5c26a8e63 100644 --- a/drivers/usb/host/xhci-plat.c +++ b/drivers/usb/host/xhci-plat.c @@ -265,6 +265,9 @@ int xhci_plat_probe(struct platform_device *pdev, struct device *sysdev, const s if (device_property_read_bool(tmpdev, "xhci-skip-phy-init-quirk")) xhci->quirks |= XHCI_SKIP_PHY_INIT; + if (device_property_read_bool(tmpdev, "xhci-full-reset-on-remove-quirk")) + xhci->quirks |= XHCI_FULL_RESET_ON_REMOVE; + device_property_read_u32(tmpdev, "imod-interval-ns", &xhci->imod_interval); } diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 90eb491267b5..4f091d618c01 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -198,6 +198,7 @@ int xhci_reset(struct xhci_hcd *xhci, u64 timeout_us) u32 command; u32 state; int ret; + unsigned int exit_state; state = readl(&xhci->op_regs->status); @@ -226,8 +227,13 @@ int xhci_reset(struct xhci_hcd *xhci, u64 timeout_us) if (xhci->quirks & XHCI_INTEL_HOST) udelay(1000); + if (xhci->quirks & XHCI_FULL_RESET_ON_REMOVE) + exit_state = 0; + else + exit_state = XHCI_STATE_REMOVING; + ret = xhci_handshake_check_state(xhci, &xhci->op_regs->command, - CMD_RESET, 0, timeout_us, XHCI_STATE_REMOVING); + CMD_RESET, 0, timeout_us, exit_state); if (ret) return ret; diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h index 242ab9fbc8ae..ac65af788298 100644 --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -1637,6 +1637,7 @@ struct xhci_hcd { #define XHCI_WRITE_64_HI_LO BIT_ULL(47) #define XHCI_CDNS_SCTX_QUIRK BIT_ULL(48) #define XHCI_ETRON_HOST BIT_ULL(49) +#define XHCI_FULL_RESET_ON_REMOVE BIT_ULL(50) unsigned int num_active_eps; unsigned int limit_active_eps;