From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6F767175A7F for ; Thu, 17 Sep 2026 07:17:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789629430; cv=none; b=K6dTMfDrVNRUvQROK21lYf4AuV3kfsjKb4WWVbYIx0grJgJAGsHsXmllYKZC2/TuXjDVqYXa2wui5Ratn3bjdmhp34HPijkSeKMvRpjPSLGF7169njlaIlWLBzJ5URXOt1XZ3KId8hhQoYHaR0XG6H1HMXweTfTZ/hrIQQtwQQM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789629430; c=relaxed/simple; bh=psMZRwkOfr0bnXRHKcURRMVFhIPKVSfM6YNHBR7Q0j8=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=B9ZTpZQ6b7gLK0ZxfdQcgI/GultOAvRic8iJR6Aqr5WupDiu+3FifMeseM8wnj2aRFy19QBV8HkwJHmm8/ag1+6i/YoZwtCqCnBJRSOxTgbPXGz58ci/hJvyJ/bqacuPTdRqX8hdQBYUqQS2iQe8iEZ4Tc8GzkhWxW8hB/RzxWg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=UKKNJcye; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="UKKNJcye" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1789629427; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=VhU95cDMBIXQvMna+tKy46BOvuCr3e2931Pn9vAkduA=; b=UKKNJcyeJoqjQ7vhRo0XcB5zVCk2o36B2NI7+Wvkq8n/UTOKNnksLwAoWHe179x+lPpBEX JshvObcuwJebYvMNaN18uSyY+ORuflUdKH+19oABQa22oVWQpgqUz4bbAsNsi2hzyr8U86 OjuKvVehlnSjJar5IH7bm9YtXUjSMbI= Received: from mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-584-AUHHK_xEM-uUnwU6D4tLMA-1; Thu, 17 Sep 2026 03:17:04 -0400 X-MC-Unique: AUHHK_xEM-uUnwU6D4tLMA-1 X-Mimecast-MFC-AGG-ID: AUHHK_xEM-uUnwU6D4tLMA_1789629422 Received: from mx-prod-int-10.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-10.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.95]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 2E17E184B3A8; Thu, 17 Sep 2026 07:17:02 +0000 (UTC) Received: from fedora.redhat.corp (headnet05.pony-001.prod.iad2.dc.redhat.com [10.2.32.117]) by mx-prod-int-10.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 0C799427; Thu, 17 Sep 2026 07:16:58 +0000 (UTC) From: Jose Ignacio Tornos Martinez To: bhelgaas@google.com, alex@shazbot.org, mani@kernel.org Cc: jjohnson@kernel.org, linux-pci@vger.kernel.org, linux-wireless@vger.kernel.org, ath11k@lists.infradead.org, ath12k@lists.infradead.org, mhi@lists.linux.dev, linux-kernel@vger.kernel.org, Jose Ignacio Tornos Martinez Subject: [PATCH v14 0/2] PCI: Add device-specific reset for Qualcomm devices Date: Thu, 17 Sep 2026 09:16:49 +0200 Message-ID: <20260917071651.14174-1-jtornosm@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.6 on 10.30.177.95 Some Qualcomm PCIe devices (WCN6855, WCN7850 WLAN; SDX62/SDX65 modems) lack working reset methods for VFIO passthrough scenarios. These devices have no FLR capability, advertise NoSoftRst+ (blocking PM reset), and have broken bus reset (addressed by quirk_no_bus_reset, merged for v7.2). VFIO attempts to reset devices on every reassignment: - For the listed modems, without a proper reset capability, these devices never successfully initialize even on first VM assignment. - For the listed WLAN devices, without a working reset method, the attempt fails. On clean VM shutdown, the guest driver properly deinitializes the device via .shutdown/.remove callbacks, leaving it in a usable state despite the failed reset. However, on unclean VM termination (crash, force-off), the guest driver callbacks are not triggered, the device remains in an undefined state (DMA active, interrupts enabled, etc.), and without a working reset it cannot be reused. Add device-specific reset methods using BAR-space hardware reset registers that exist in these devices: Patch 1: SDX62/SDX65 modem reset via MHI SoC reset Patch 2: WCN6855/WCN7850 WLAN reset via SoC global reset These are true hardware reset mechanisms (not power management or firmware error recovery), providing proper device reset for VFIO scenarios. Testing shows stable operation over 100+ VM crash/reset cycles. Device- specific reset is position #1 in the reset hierarchy, so these devices will use hardware reset as their primary reset method. Jose Ignacio Tornos Martinez (2): PCI: Add device-specific reset for Qualcomm SDX62/SDX65 modems PCI: Add device-specific reset for Qualcomm WCN6855/WCN7850 WLAN drivers/pci/quirks.c | 116 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 116 insertions(+) --- v14: Address Bjorn Helgaas feedback: - Split WLAN and modem resets into two separate patches - Clarify commit message for WLAN devices: VFIO resets on every reassignment, clean shutdown leaves device in usable state via driver callbacks, but unclean termination is where the lack of reset is critical - No code changes from v13, only patch split and commit message clarification (Mani's Reviewed-by retained) v13: https://lore.kernel.org/all/20260915223634.GA878346@bhelgaas/ -- 2.54.0