From mboxrd@z Thu Jan 1 00:00:00 1970 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D457CC982CD for ; Thu, 17 Sep 2026 07:17:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:content-type: Content-Transfer-Encoding:MIME-Version:References:In-Reply-To:Message-ID:Date :Subject:Cc:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=6oVowQPD2pzOvsnV2vQtmoDtP9e65GcjkY+VkNiJx7c=; b=XERJI+0AGW/J8gJxZYVy0IuXWR +FAJUC4P1OyDFB/J9fg4V86bEQOD9BD976AmiIsK4xcNS6ycA3N3AbZQATjf5Q6CtQ1DU7YfW3II9 5qE8g0A64RzTT2oBX2xf9jtxOMNg0hF/ZW80TQrjGR9zMkqADwzkYQQT0+zQ413KfuxdYufZoj5xk A2yGfbAkR8WGluF6Bg8O7KFve7mbn3H94i7NKXO5quilYNrJaFr1cMqhtFsNGgMwx42oHW1t8PJnM tHaYCE+FiNlnUXCV5nwZA8XAYDEkWnkwbh/xa9110UelSzYTbLCYgs4MLPrDrhTj6f/UznbvoZnwj pc5UKQpg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1x76Mw-0000000Akej-2vEK; Thu, 17 Sep 2026 07:17:18 +0000 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1x76Mu-0000000Akcy-1oCE for ath11k@lists.infradead.org; Thu, 17 Sep 2026 07:17:17 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1789629435; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=6oVowQPD2pzOvsnV2vQtmoDtP9e65GcjkY+VkNiJx7c=; b=f3X3qdXxeFJjMFO0bhSzADjCDVOF3NtTE9UU+Nl2ttuQlJIPmdZaeZWpy+hDxy9P3FZK3M 3vc4G3YPfh01IAWLXzcGVKcFd/nwKmOkp/B9F0ZHgk22wtkOKEvsQmDEsF3x2lOjm1H1jI QVK/gsczY82V7x/qgzTivXxt7PPVGSI= Received: from mx-prod-mc-01.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-348-60u2YI-APXKyemquFbe4Cg-1; Thu, 17 Sep 2026 03:17:10 -0400 X-MC-Unique: 60u2YI-APXKyemquFbe4Cg-1 X-Mimecast-MFC-AGG-ID: 60u2YI-APXKyemquFbe4Cg_1789629428 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-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 44EE9195DE7A; Thu, 17 Sep 2026 07:17:08 +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 AA97E427; Thu, 17 Sep 2026 07:17:04 +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 1/2] PCI: Add device-specific reset for Qualcomm SDX62/SDX65 modems Date: Thu, 17 Sep 2026 09:16:50 +0200 Message-ID: <20260917071651.14174-2-jtornosm@redhat.com> In-Reply-To: <20260917071651.14174-1-jtornosm@redhat.com> References: <20260917071651.14174-1-jtornosm@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.6 on 10.30.177.95 X-Mimecast-MFC-PROC-ID: sIg7ik6EMs_5RwzeXTwkAg1ShL6lTKMlEo-SCsvAjUQ_1789629428 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit content-type: text/plain; charset="US-ASCII"; x-default=true X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260917_001716_557898_7C1C0108 X-CRM114-Status: GOOD ( 14.19 ) X-BeenThere: ath11k@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "ath11k" Errors-To: ath11k-bounces+ath11k=archiver.kernel.org@lists.infradead.org Qualcomm SDX62/SDX65 5G modems (17cb:0308) 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. Without a proper reset capability, these devices never successfully initialize even on first VM assignment. Add a device-specific reset method using BAR-space hardware reset registers that exist in these devices. SDX62/SDX65 modem devices use MHI SoC reset via BAR0 (sequence from MHI driver: mhi_soc_reset(), mhi_pci_reset_prepare()): - Write reset request to offset 0xb0 - Wait 2 seconds for reset completion This is a true hardware reset mechanism (not power management or firmware error recovery), providing proper device reset for VFIO scenarios. Testing shows stable operation over 109 VM crash/reset cycles. Device- specific reset is position #1 in the reset hierarchy, so these Qualcomm devices will use hardware reset as their primary reset method. Signed-off-by: Jose Ignacio Tornos Martinez Reviewed-by: Manivannan Sadhasivam --- v14: Address Bjorn Helgaas feedback: - Split WLAN and modem resets into two separate patches - 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/ drivers/pci/quirks.c | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index de9bbccda21f..e72af7d2c775 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -4230,6 +4230,45 @@ static int reset_hinic_vf_dev(struct pci_dev *pdev, bool probe) return 0; } +#define MHI_SOC_RESET_REQ_OFFSET 0xb0 +#define MHI_SOC_RESET_REQ BIT(0) + +/* + * Qualcomm modem device-specific reset using MHI SoC reset via BAR0 + * register. + */ +static int reset_qualcomm_modem(struct pci_dev *pdev, bool probe) +{ + void __iomem *bar; + u16 cmd; + + if (probe) + return 0; + + if (pdev->current_state != PCI_D0) + return -EINVAL; + + pci_read_config_word(pdev, PCI_COMMAND, &cmd); + pci_write_config_word(pdev, PCI_COMMAND, cmd | PCI_COMMAND_MEMORY); + + bar = pci_iomap(pdev, 0, 0); + if (!bar) { + pci_write_config_word(pdev, PCI_COMMAND, cmd); + return -ENODEV; + } + + iowrite32(MHI_SOC_RESET_REQ, bar + MHI_SOC_RESET_REQ_OFFSET); + ioread32(bar + MHI_SOC_RESET_REQ_OFFSET); + + /* Be sure device reset has been executed */ + msleep(2000); + + pci_iounmap(pdev, bar); + pci_write_config_word(pdev, PCI_COMMAND, cmd); + + return 0; +} + static const struct pci_dev_reset_methods pci_dev_reset_methods[] = { { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82599_SFP_VF, reset_intel_82599_sfp_virtfn }, @@ -4245,6 +4284,7 @@ static const struct pci_dev_reset_methods pci_dev_reset_methods[] = { reset_chelsio_generic_dev }, { PCI_VENDOR_ID_HUAWEI, PCI_DEVICE_ID_HINIC_VF, reset_hinic_vf_dev }, + { PCI_VENDOR_ID_QCOM, 0x0308, reset_qualcomm_modem }, /* SDX62/SDX65 modems */ { 0 } }; -- 2.54.0