From patchwork Mon Jul 10 14:59:51 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: 9833179 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 581C360318 for ; Mon, 10 Jul 2017 15:00:23 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 482EF26BE9 for ; Mon, 10 Jul 2017 15:00:23 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3BED528509; Mon, 10 Jul 2017 15:00:23 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.1 required=2.0 tests=BAYES_00,DKIM_SIGNED, FREEMAIL_FROM, RCVD_IN_DNSWL_MED, T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id B1C3326BE9 for ; Mon, 10 Jul 2017 15:00:22 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 045126E18B; Mon, 10 Jul 2017 15:00:08 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from pegasos-out.vodafone.de (pegasos-out.vodafone.de [80.84.1.38]) by gabe.freedesktop.org (Postfix) with ESMTP id 9AA106E185 for ; Mon, 10 Jul 2017 15:00:05 +0000 (UTC) Received: from localhost (localhost.localdomain [127.0.0.1]) by pegasos-out.vodafone.de (Rohrpostix1 Daemon) with ESMTP id 09A072621E3; Mon, 10 Jul 2017 17:00:01 +0200 (CEST) X-Virus-Scanned: amavisd-new at vodafone.de 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 H3BdxwKnrFU6; Mon, 10 Jul 2017 16:59:59 +0200 (CEST) Received: from smtp-01.vodafone.de (xsmail-dmz5.prod.vfnet.de [10.215.254.36]) by pegasos-out.vodafone.de (Rohrpostix1 Daemon) with ESMTP id 5FC4626219B; Mon, 10 Jul 2017 16:59:59 +0200 (CEST) X-DKIM: OpenDKIM Filter v2.6.8 pegasos-out.vodafone.de 5FC4626219B DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=vodafone.de; s=mail; t=1499698799; bh=tnPYi9QpL6rPCksXeHLK3gikcT7NRh394upmJwRKhrg=; h=From:To:Subject:Date:In-Reply-To:References; b=dvlgYeW35iOaoDd31MrSpWjQd3DOAzCm6kngjlgVQ10862UAGmOVnXFiW9W5DgyiB xgPIFHwzXg9AiJw3urAVLRba8sljqeAYp5lqo4o42DSRCCRsr7+ZIizKU5dzkvyjb4 rWgSTplOB68Wsoc5oT+ZSO1HihKtRJBkryGqepcM= X-Virus-Scanned: amavisd-new at vodafone.de Received: from smtp-01.vodafone.de ([127.0.0.1]) by localhost (xsmail-dmz5.prod.vfnet.de [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id CAzDl2oTs19b; Mon, 10 Jul 2017 16:59:58 +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 v8 3/6] PCI: add functionality for resizing resources v7 Date: Mon, 10 Jul 2017 16:59:51 +0200 Message-Id: <1499698794-1718-4-git-send-email-deathsimple@vodafone.de> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1499698794-1718-1-git-send-email-deathsimple@vodafone.de> References: <1499698794-1718-1-git-send-email-deathsimple@vodafone.de> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP 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. Drivers should use the following sequence to resize their BARs: 1. Disable memory decoding of your device using the PCI cfg dword. 2. Use pci_release_resource() to release all BARs which can move during the resize. Including the one you want to resize. 3. Call pci_resize_resource() for each BAR you want to resize. 4. Call pci_assign_unassigned_bus_resources() to reassign new locations for all BARs which are not resized, but could move. 5. If everything worked as expected enable memory decoding in your device again using the PCI cfg dword. 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 v7: Document in the commit message how to use the new function. 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 37450d9..03af25b 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 85774b7..1d558e1 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 4869e66..7e486e3 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1080,6 +1080,8 @@ 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); @@ -1158,6 +1160,7 @@ 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 *),