From patchwork Tue Oct 7 04:37:54 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Benjamin Herrenschmidt X-Patchwork-Id: 397122 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 84AE014007B for ; Tue, 7 Oct 2014 17:57:44 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752654AbaJGG5m (ORCPT ); Tue, 7 Oct 2014 02:57:42 -0400 Received: from gate.crashing.org ([63.228.1.57]:37327 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752548AbaJGG5m (ORCPT ); Tue, 7 Oct 2014 02:57:42 -0400 Received: from localhost (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.13.8) with ESMTP id s974btmL030460; Mon, 6 Oct 2014 23:37:57 -0500 Message-ID: <1412656674.30859.120.camel@pasglop> Subject: [PATCH v3 2/7] pci/msi: Add device flag indicating that 64-bit MSIs don't work From: Benjamin Herrenschmidt To: Alex Deucher , Bjorn Helgaas Cc: Dave Airlie , Brian King , Takashi Iwai , linux-pci@vger.kernel.org, Yijing Wang , Anton Blanchard , linuxppc-dev@ozlabs.org Date: Tue, 07 Oct 2014 15:37:54 +1100 X-Mailer: Evolution 3.12.2 Mime-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org This can be set by quirks/drivers to be used by the architecture code that assigns the MSI addresses. We additionally add verification in the core MSI code that the values assigned by the architecture do satisfy the limitation in order to fail gracefully if they don't (ie. the arch hasn't been updated to deal with that quirk yet). Signed-off-by: Benjamin Herrenschmidt CC: --- drivers/pci/msi.c | 26 ++++++++++++++++++++++++++ include/linux/pci.h | 1 + 2 files changed, 27 insertions(+) -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 5a40516..6807edd 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -610,6 +610,20 @@ static struct msi_desc *msi_setup_entry(struct pci_dev *dev) return entry; } +static int msi_verify_entries(struct pci_dev *dev) +{ + struct msi_desc *entry; + + list_for_each_entry(entry, &dev->msi_list, list) { + if (!dev->no_64bit_msi || !entry->msg.address_hi) + continue; + dev_err(&dev->dev, "Device has broken 64-bit MSI but arch" + " tried to assign one above 4G\n"); + return -EIO; + } + return 0; +} + /** * msi_capability_init - configure device's MSI capability structure * @dev: pointer to the pci_dev data structure of MSI device function @@ -647,6 +661,13 @@ static int msi_capability_init(struct pci_dev *dev, int nvec) return ret; } + ret = msi_verify_entries(dev); + if (ret) { + msi_mask_irq(entry, mask, ~mask); + free_msi_irqs(dev); + return ret; + } + ret = populate_msi_sysfs(dev); if (ret) { msi_mask_irq(entry, mask, ~mask); @@ -760,6 +781,11 @@ static int msix_capability_init(struct pci_dev *dev, if (ret) goto out_avail; + /* Check if all MSI entries honor device restrictions */ + ret = msi_verify_entries(dev); + if (ret) + goto out_free; + /* * Some devices require MSI-X to be enabled before we can touch the * MSI-X registers. We need to mask all the vectors to prevent diff --git a/include/linux/pci.h b/include/linux/pci.h index 96453f9..6b6da8f 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -331,6 +331,7 @@ struct pci_dev { unsigned int is_added:1; unsigned int is_busmaster:1; /* device is busmaster */ unsigned int no_msi:1; /* device may not use msi */ + unsigned int no_64bit_msi:1; /* device may only use 32-bit MSIs */ unsigned int block_cfg_access:1; /* config space access is blocked */ unsigned int broken_parity_status:1; /* Device generates false positive parity */ unsigned int irq_reroute_variant:2; /* device needs IRQ rerouting variant */