From patchwork Thu Feb 24 22:47:42 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bjorn Helgaas X-Patchwork-Id: 12759366 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 56D5AC433EF for ; Thu, 24 Feb 2022 22:48:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235521AbiBXWsd (ORCPT ); Thu, 24 Feb 2022 17:48:33 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58644 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235738AbiBXWsa (ORCPT ); Thu, 24 Feb 2022 17:48:30 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 02C85B8B69; Thu, 24 Feb 2022 14:48:00 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 9415F61B8A; Thu, 24 Feb 2022 22:47:59 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B05EAC340E9; Thu, 24 Feb 2022 22:47:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1645742879; bh=7GVjZdt8jWnoINbadQgUAxYf5QWMGlUdkV2jOsP6HN4=; h=From:To:Cc:Subject:Date:From; b=J3uHZvyyd0e8lJq53oQvw1sHr6upV9/XivUeSEVIkBjDPzDN/imiJfEz3/5PdpqbX nzmw7DsxUeyHyVWf2OkQMcNLJRrotyHoFlKpzyv3nZ/zx0nsvFc/tR4Ylm8WdGqEyR u6ztZO7HYMU3dw905FdN1cfM+BxuyHMyTgZn04bAXm1V8Ob+mXd5t35BjcL8wRW3qY 0AwpZWYaRHH208L3DGYwk9IJ/hQpJs5ks3KDvofMwsqlPcVvzuGZKJL6VCo+ZPDKsI idAY/AzV7nDP3hvXKuya9hYhCqgtE7oQ+dUJRrLh6O5cnyKcguA2HRtCawvGKikH7m 4en7+JBFp4hag== From: Bjorn Helgaas To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann Cc: David Airlie , Daniel Vetter , Xuefeng Li , Huacai Chen , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Bjorn Helgaas Subject: [PATCH v9 00/11] vgaarb: Rework default VGA device selection Date: Thu, 24 Feb 2022 16:47:42 -0600 Message-Id: <20220224224753.297579-1-helgaas@kernel.org> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org From: Bjorn Helgaas Current default VGA device selection fails in some cases because part of it is done in the vga_arb_device_init() subsys_initcall, and some arches enumerate PCI devices in pcibios_init(), which runs *after* that. The big change from the v8 posting is that this moves vgaarb.c from drivers/gpu/vga to drivers/pci because it really has nothing to do with GPUs or DRM. For example: - On BMC system, the AST2500 bridge [1a03:1150] does not implement PCI_BRIDGE_CTL_VGA. This is perfectly legal but means the legacy VGA resources won't reach downstream devices unless they're included in the usual bridge windows. - vga_arb_select_default_device() will set a device below such a bridge as the default VGA device as long as it has PCI_COMMAND_IO and PCI_COMMAND_MEMORY enabled. - vga_arbiter_add_pci_device() is called for every VGA device, either at boot-time or at hot-add time, and it will also set the device as the default VGA device, but ONLY if all bridges leading to it implement PCI_BRIDGE_CTL_VGA. - This difference between vga_arb_select_default_device() and vga_arbiter_add_pci_device() means that a device below an AST2500 or similar bridge can only be set as the default if it is enumerated before vga_arb_device_init(). - On ACPI-based systems, PCI devices are enumerated by acpi_init(), which runs before vga_arb_device_init(). - On non-ACPI systems, like on MIPS system, they are enumerated by pcibios_init(), which typically runs *after* vga_arb_device_init(). This series consolidates all the default VGA device selection in vga_arbiter_add_pci_device(), which is always called after enumerating a PCI device. Almost all the work here is Huacai's. I restructured it a little bit and added a few trivial patches on top. Bjorn Version history: V0 original implementation as final quirk to set default device. https://lore.kernel.org/r/20210514080025.1828197-6-chenhuacai@loongson.cn V1 rework vgaarb to do all default device selection in vga_arbiter_add_pci_device(). https://lore.kernel.org/r/20210705100503.1120643-1-chenhuacai@loongson.cn V2 move arbiter to PCI subsystem, fix nits. https://lore.kernel.org/r/20210722212920.347118-1-helgaas@kernel.org V3 rewrite the commit log of the last patch (which is also summarized by Bjorn). https://lore.kernel.org/r/20210820100832.663931-1-chenhuacai@loongson.cn V4 split the last patch to two steps. https://lore.kernel.org/r/20210827083129.2781420-1-chenhuacai@loongson.cn V5 split Patch-9 again and sort the patches. https://lore.kernel.org/r/20210911093056.1555274-1-chenhuacai@loongson.cn V6 split Patch-5 again and sort the patches again. https://lore.kernel.org/r/20210916082941.3421838-1-chenhuacai@loongson.cn V7 stop moving vgaarb to drivers/pci because of ordering issues with misc_init(). https://lore.kernel.org/r/20211015061512.2941859-1-chenhuacai@loongson.cn https://lore.kernel.org/r/CAAhV-H7FhAjM-Ha42Z1dLrE4PvC9frfyeU27KHWcyWKkMftEsA@mail.gmail.com V8 expand commit logs, rework boot VGA device selection https://lore.kernel.org/r/20220106000658.243509-1-helgaas@kernel.org V9 (this posting) move to drivers/pci, resolve initcall ordering, rename vga_is_framebuffer_device() to vga_is_firmware_default() Bjorn Helgaas (5): PCI/VGA: Move vgaarb to drivers/pci PCI/VGA: Factor out vga_select_framebuffer_device() PCI/VGA: Remove empty vga_arb_device_card_gone() PCI/VGA: Use unsigned format string to print lock counts PCI/VGA: Replace full MIT license text with SPDX identifier Huacai Chen (6): PCI/VGA: Move vga_arb_integrated_gpu() earlier in file PCI/VGA: Factor out default VGA device selection PCI/VGA: Move firmware default device detection to ADD_DEVICE path PCI/VGA: Move non-legacy VGA detection to ADD_DEVICE path PCI/VGA: Move disabled VGA device detection to ADD_DEVICE path PCI/VGA: Log bridge control messages when adding devices drivers/gpu/vga/Kconfig | 19 -- drivers/gpu/vga/Makefile | 1 - drivers/pci/Kconfig | 19 ++ drivers/pci/Makefile | 1 + drivers/{gpu/vga => pci}/vgaarb.c | 313 +++++++++++++++--------------- 5 files changed, 175 insertions(+), 178 deletions(-) rename drivers/{gpu/vga => pci}/vgaarb.c (90%)