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 6065149690A for ; Tue, 9 Jun 2026 16:37:07 +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=1781023030; cv=none; b=FD9fyLueeHE4lKPVZOst5YDxgkPBgliXTNzIyuyMf20NZo9n+9Xxt8AuMo8bTBxz2fCW6S300SXExm34/MT+RgwOnNqDnxjlbXNz+UZk7qvyE4kY1RhFY4nun9PzGwiQXclCRBcIGroJNWvwBg5FdBx68YBu7iD9aXPSIIV9sEc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781023030; c=relaxed/simple; bh=IL9COutDyO8RGv6CNQA+EBUtMk3FFt8zFi+o57rRRo8=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=tl9rJHeJDDg5SQMg9JQHGie82o0fvd8mu0FLd4U/ajjKPUtzVeZSeMeEzZDfxjSPcu9U+a5JUfN8DHk2OzVH2QW3JFe2BTsVWDiDFRYiedsS1wscrXvGHmpkUTrYtsKpvR96gw3pqnBSi8zdiB6cf7S1ljXLstclKz1JrjF13hk= 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=UnsqEJZ7; 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="UnsqEJZ7" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1781023026; 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=Mli8j5vHP+lIm+xGChsHaTECZChyQ7K/C3hHJV9kyUc=; b=UnsqEJZ7Sf2m5qnDvMxcI7KtVNtCNt3n+t9d64F+RZN6t1kTcoV5+cKrxVwUfPNh8rWq0/ SZOihDSLmlxJH/36ELpShHf/+5Ihvtik/YYcVkVN8xs9v7vKlfi6LGwbY/gqCQjh5JrkPN SDy/1VsUSTpSFdAGE6ebCR0alw4wVuo= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-536-E0wiNN4tPBOamtK6RgatAA-1; Tue, 09 Jun 2026 12:37:00 -0400 X-MC-Unique: E0wiNN4tPBOamtK6RgatAA-1 X-Mimecast-MFC-AGG-ID: E0wiNN4tPBOamtK6RgatAA_1781023018 Received: from mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.111]) (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-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id CE3B51964CD1; Tue, 9 Jun 2026 16:36:57 +0000 (UTC) Received: from fedora.redhat.com (unknown [10.44.32.77]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 0814C1800662; Tue, 9 Jun 2026 16:36:53 +0000 (UTC) From: Jose Ignacio Tornos Martinez To: bhelgaas@google.com, alex@shazbot.org Cc: jjohnson@kernel.org, mani@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 v8 0/3] PCI: Add d3cold and device-specific reset for Qualcomm devices Date: Tue, 9 Jun 2026 18:36:46 +0200 Message-ID: <20260609163649.319755-1-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 3.4.1 on 10.30.177.111 Some PCIe devices lack working reset methods for VFIO passthrough scenarios. These devices typically have no FLR, advertise NoSoftRst+ (blocking PM reset), and have broken or unavailable bus reset. When a VM crashes, VFIO cannot reset the device for reuse without a working reset method. This series addresses the problem by adding general d3cold infrastructure and device-specific reset for Qualcomm devices: **Patch 1/3: d3cold reset method** Adds D3cold as a general reset method with strict _PR3 requirement. Only attempts true power cycling via platform control (ACPI _PR3), never falls back to D3hot. This provides genuine power-off reset on platforms that support it. **Patch 2/3: device-specific reset for Qualcomm devices** Adds device-specific reset entries for Qualcomm WCN6855/WCN7850 WiFi cards and SDX62/SDX65 modems using D3cold power cycling with automatic D3hot fallback. Uses pci_set_power_state(D3cold) which automatically falls back to D3hot on platforms without _PR3. Extracts shared pci_dev_d3cold_d0_cycle() helper to avoid code duplication with general d3cold method. Device-specific reset is position #1 in reset hierarchy, providing immediate working reset for these Qualcomm devices. **Patch 3/3: Qualcomm quirk_no_bus_reset** Disables broken bus reset for Qualcomm devices. Testing proves this is device-specific: MediaTek MT7925e works correctly with bus reset using the same passive M.2-to-PCIe adapters where Qualcomm devices fail, confirming PERST# is properly wired and the issue is not deployment-specific. Acts as safety net to prevent broken SBR if users override via sysfs. v8: Fix commit message in patch 2/3: correct IOMMU handling description Patches 1/3 and 3/3 unchanged from v7 v7: https://lore.kernel.org/all/20260603105853.326290-1-jtornosm@redhat.com/ Jose Ignacio Tornos Martinez (3): PCI: Add d3cold as general reset method PCI: Add device-specific reset for Qualcomm devices PCI: Disable broken bus reset on Qualcomm devices -- 2.53.0