From patchwork Fri Jun 9 08:59:44 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Christian_K=C3=B6nig?= X-Patchwork-Id: 773725 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 3wkc1v56fNz9s76 for ; Fri, 9 Jun 2017 19:09:55 +1000 (AEST) Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=vodafone.de header.i=@vodafone.de header.b="Z7bJS4gw"; dkim-atps=neutral Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751755AbdFIJJr (ORCPT ); Fri, 9 Jun 2017 05:09:47 -0400 Received: from pegasos-out.vodafone.de ([80.84.1.38]:59411 "EHLO pegasos-out.vodafone.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751874AbdFIJIX (ORCPT ); Fri, 9 Jun 2017 05:08:23 -0400 Received: from localhost (localhost.localdomain [127.0.0.1]) by pegasos-out.vodafone.de (Rohrpostix1 Daemon) with ESMTP id 661AF261FAD; Fri, 9 Jun 2017 11:08:14 +0200 (CEST) X-Virus-Scanned: amavisd-new at vodafone.de X-Spam-Flag: NO X-Spam-Score: -0.055 X-Spam-Level: X-Spam-Status: No, score=-0.055 tagged_above=-999 required=4 tests=[ALL_TRUSTED=-1, BAYES_99=1.3, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, RP_MATCHES_RCVD=-0.245, T_RP_MATCHES_RCVD=-0.01] autolearn=disabled Authentication-Results: rohrpostix1.prod.vfnet.de (amavisd-new); dkim=pass header.i=@vodafone.de Received: from pegasos-out.vodafone.de ([127.0.0.1]) by localhost (rohrpostix1.prod.vfnet.de [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 5x8GRkGQT8mV; Fri, 9 Jun 2017 11:08:12 +0200 (CEST) Received: from smtp-03.vodafone.de (smtp-03.vodafone.de [10.215.254.38]) by pegasos-out.vodafone.de (Rohrpostix1 Daemon) with ESMTP id D3DED261FA1; Fri, 9 Jun 2017 11:08:11 +0200 (CEST) X-DKIM: OpenDKIM Filter v2.6.8 pegasos-out.vodafone.de D3DED261FA1 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=vodafone.de; s=mail; t=1496999291; bh=Wa7Ayl2zfpBECVOghZB76OmcPPPNc/I1Cx9r0IauMe4=; h=From:To:Subject:Date:In-Reply-To:References; b=Z7bJS4gwc50SCUt2X9q66wY6wilKGOMn4EnwQMdnx5CtHqIp7as9roR6cGPZsWC0F b9uewNr/NFt7RjnPxVE+LFS8IbAZgWl5nLEuDygaVw3hHqpeWxZmzeZbNfogmGMYcD 2GCOuc1j68u4t5rxzkh+cmWTG6pyZ3mrR7ZTUqkU= X-Virus-Scanned: amavisd-new at vodafone.de Received: from smtp-03.vodafone.de ([127.0.0.1]) by localhost (xsmail-dmz7.prod.vfnet.de [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 4v2wc9qeIK31; Fri, 9 Jun 2017 11:08:07 +0200 (CEST) From: =?UTF-8?q?Christian=20K=C3=B6nig?= To: helgaas@kernel.org, linux-pci@vger.kernel.org, dri-devel@lists.freedesktop.org, platform-driver-x86@vger.kernel.org, linux-kernel@vger.kernel.org, amd-gfx@lists.freedesktop.org Subject: [PATCH v5 3/6] PCI: add functionality for resizing resources v6 Date: Fri, 9 Jun 2017 10:59:44 +0200 Message-Id: <1496998787-6371-4-git-send-email-deathsimple@vodafone.de> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1496998787-6371-1-git-send-email-deathsimple@vodafone.de> References: <1496998787-6371-1-git-send-email-deathsimple@vodafone.de> MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org From: Christian König This allows device drivers to request resizing their BARs. The function only tries to reprogram the windows of the bridge directly above the requesting device and only the BAR of the same type (usually mem, 64bit, prefetchable). This is done to make sure not to disturb other drivers by changing the BARs of their devices. If reprogramming the bridge BAR fails the old status is restored and -ENOSPC returned to the calling device driver. v2: rebase on changes in rbar support v3: style cleanups, fail if memory decoding is enabled or resources still allocated, resize all unused bridge BARs, drop calling pci_reenable_device v4: print resources before releasing them, style cleanups, use pci_rbar_size_to_bytes, use PCI_RES_TYPE_MASK v5: use next pointer to simplify loop v6: move reassigning resources on error to driver side Signed-off-by: Christian König --- drivers/pci/setup-bus.c | 98 +++++++++++++++++++++++++++++++++++++++++++++++++ drivers/pci/setup-res.c | 58 +++++++++++++++++++++++++++++ include/linux/pci.h | 3 ++ 3 files changed, 159 insertions(+) diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index 451a9c0..2ea872d 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -1908,6 +1908,104 @@ void pci_assign_unassigned_bridge_resources(struct pci_dev *bridge) } EXPORT_SYMBOL_GPL(pci_assign_unassigned_bridge_resources); +int pci_reassign_bridge_resources(struct pci_dev *bridge, unsigned long type) +{ + struct pci_dev_resource *dev_res; + struct pci_dev *next; + LIST_HEAD(saved); + LIST_HEAD(added); + LIST_HEAD(failed); + unsigned int i; + int ret; + + /* Walk to the root hub, releasing bridge BARs when possible */ + next = bridge; + do { + bridge = next; + for (i = PCI_BRIDGE_RESOURCES; i < PCI_BRIDGE_RESOURCE_END; + i++) { + struct resource *res = &bridge->resource[i]; + + if ((res->flags ^ type) & PCI_RES_TYPE_MASK) + continue; + + /* Ignore BARs which are still in use */ + if (res->child) + continue; + + ret = add_to_list(&saved, bridge, res, 0, 0); + if (ret) + goto cleanup; + + dev_info(&bridge->dev, "BAR %d: releasing %pR\n", + i, res); + + if (res->parent) + release_resource(res); + res->start = 0; + res->end = 0; + break; + } + if (i == PCI_BRIDGE_RESOURCE_END) + break; + + next = bridge->bus ? bridge->bus->self : NULL; + } while (next); + + if (list_empty(&saved)) + return -ENOENT; + + __pci_bus_size_bridges(bridge->subordinate, &added); + __pci_bridge_assign_resources(bridge, &added, &failed); + BUG_ON(!list_empty(&added)); + + if (!list_empty(&failed)) { + ret = -ENOSPC; + goto cleanup; + } + + list_for_each_entry(dev_res, &saved, list) { + /* Skip the bridge we just assigned resources for. */ + if (bridge == dev_res->dev) + continue; + + bridge = dev_res->dev; + pci_setup_bridge(bridge->subordinate); + } + + free_list(&saved); + return 0; + +cleanup: + /* restore size and flags */ + list_for_each_entry(dev_res, &failed, list) { + struct resource *res = dev_res->res; + + res->start = dev_res->start; + res->end = dev_res->end; + res->flags = dev_res->flags; + } + free_list(&failed); + + /* Revert to the old configuration */ + list_for_each_entry(dev_res, &saved, list) { + struct resource *res = dev_res->res; + + bridge = dev_res->dev; + i = res - bridge->resource; + + res->start = dev_res->start; + res->end = dev_res->end; + res->flags = dev_res->flags; + + pci_claim_resource(bridge, i); + pci_setup_bridge(bridge->subordinate); + } + free_list(&saved); + + return ret; +} + void pci_assign_unassigned_bus_resources(struct pci_bus *bus) { struct pci_dev *dev; diff --git a/drivers/pci/setup-res.c b/drivers/pci/setup-res.c index 4bc589e..077c515 100644 --- a/drivers/pci/setup-res.c +++ b/drivers/pci/setup-res.c @@ -383,6 +383,64 @@ int pci_reassign_resource(struct pci_dev *dev, int resno, resource_size_t addsiz return 0; } +void pci_release_resource(struct pci_dev *dev, int resno) +{ + struct resource *res = dev->resource + resno; + + dev_info(&dev->dev, "BAR %d: releasing %pR\n", resno, res); + release_resource(res); + res->end = resource_size(res) - 1; + res->start = 0; + res->flags |= IORESOURCE_UNSET; +} +EXPORT_SYMBOL(pci_release_resource); + +int pci_resize_resource(struct pci_dev *dev, int resno, int size) +{ + struct resource *res = dev->resource + resno; + int old, ret; + u32 sizes; + u16 cmd; + + /* Make sure the resource isn't assigned before resizing it. */ + if (!(res->flags & IORESOURCE_UNSET)) + return -EBUSY; + + pci_read_config_word(dev, PCI_COMMAND, &cmd); + if (cmd & PCI_COMMAND_MEMORY) + return -EBUSY; + + sizes = pci_rbar_get_possible_sizes(dev, resno); + if (!sizes) + return -ENOTSUPP; + + if (!(sizes & BIT(size))) + return -EINVAL; + + old = pci_rbar_get_current_size(dev, resno); + if (old < 0) + return old; + + ret = pci_rbar_set_size(dev, resno, size); + if (ret) + return ret; + + res->end = res->start + pci_rbar_size_to_bytes(size) - 1; + + /* Check if the new config works by trying to assign everything. */ + ret = pci_reassign_bridge_resources(dev->bus->self, res->flags); + if (ret) + goto error_resize; + + return 0; + +error_resize: + pci_rbar_set_size(dev, resno, old); + res->end = res->start + pci_rbar_size_to_bytes(old) - 1; + return ret; +} +EXPORT_SYMBOL(pci_resize_resource); + int pci_enable_resources(struct pci_dev *dev, int mask) { u16 cmd, old_cmd; diff --git a/include/linux/pci.h b/include/linux/pci.h index eb3da1a..2d631ad 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1068,6 +1068,8 @@ void pci_reset_bridge_secondary_bus(struct pci_dev *dev); void pci_update_resource(struct pci_dev *dev, int resno); int __must_check pci_assign_resource(struct pci_dev *dev, int i); int __must_check pci_reassign_resource(struct pci_dev *dev, int i, resource_size_t add_size, resource_size_t align); +void pci_release_resource(struct pci_dev *dev, int resno); +int __must_check pci_resize_resource(struct pci_dev *dev, int i, int size); int pci_select_bars(struct pci_dev *dev, unsigned long flags); bool pci_device_is_present(struct pci_dev *pdev); void pci_ignore_hotplug(struct pci_dev *dev); @@ -1148,6 +1150,7 @@ void pci_assign_unassigned_resources(void); void pci_assign_unassigned_bridge_resources(struct pci_dev *bridge); void pci_assign_unassigned_bus_resources(struct pci_bus *bus); void pci_assign_unassigned_root_bus_resources(struct pci_bus *bus); +int pci_reassign_bridge_resources(struct pci_dev *bridge, unsigned long type); void pdev_enable_device(struct pci_dev *); int pci_enable_resources(struct pci_dev *, int mask); void pci_fixup_irqs(u8 (*)(struct pci_dev *, u8 *),