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 X-Spam-Level: X-Spam-Status: No, score=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 22E1CC4338F for ; Mon, 26 Jul 2021 18:07:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0613660F6E for ; Mon, 26 Jul 2021 18:07:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232184AbhGZR1L (ORCPT ); Mon, 26 Jul 2021 13:27:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52462 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231248AbhGZR07 (ORCPT ); Mon, 26 Jul 2021 13:26:59 -0400 Received: from mail-io1-xd2c.google.com (mail-io1-xd2c.google.com [IPv6:2607:f8b0:4864:20::d2c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F1F42C061757; Mon, 26 Jul 2021 11:07:27 -0700 (PDT) Received: by mail-io1-xd2c.google.com with SMTP id m13so12964205iol.7; Mon, 26 Jul 2021 11:07:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=drzvjYjf9v4fqS1iU+Dz/o3PJvwLUgUtNuIzGT8WydQ=; b=dYH2Rpw/sGNj8TqMiLdymjdVY0FzhPA2uRtfUYyplAfZJUPu2kQNs9ZE5ukJ7zwrqI spKKtLHkqgweKrKQJkL33rVdZmel/h2nL+DpEXiEFU+tQ6VzbXyussz3pEKylFicPeXV 63B2VUJf1ckMqk4adXnYjxg5pWrY8Y2nalAejKBp+M2C1bchiqbIoo3V1NwZWKC23Qa0 K/q+U4zfKlC4q3xXgy4R4SOgZSxlHJLWpmJUkuBWCcYlT3/y0zgYT59W06F4n06bvQQH MDpf1W68m5KMPyJTtCSMU7STejgPaLwpkCl8qbSCQuIYAEw1qdXGLp9BVlmyxW6H5L46 dSvA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=drzvjYjf9v4fqS1iU+Dz/o3PJvwLUgUtNuIzGT8WydQ=; b=PGlVJzWPd5lK5qv87Z87Yd+Tax8AZBBHc2THWncxe7NNkHcR29HRjkRjruEe86hlTt byo3u16rlHfv6HipoPY40lmJSrx0ekvhWQxU0AqLDTlVGSOzHporT3U7MSgG4ZE3FQue PE4GJxsuVlEeRnbTN+/5pJ9hNIJKO2p4g7hWMp7FttXF3kEutkFD7dRbv3ercBkg3CNi VeeD81VQU/pW/Ri79qBKmn6k3e4e4waNYqGo+NpTIWHdnJmAQUa8ou1hEjR8C2y1MdPq CD0haTjRmHTxsN961l1EPy0gkH89edkgN+6g2h+P7ErnujSmkPwQyB1vvpmRcQAxqBlX YVKQ== X-Gm-Message-State: AOAM533qpfFFUGKZlHsHnt/tJg2Ce08yRUA/iyUALyObQR8Ryq+wbdmT byO3BnQPQP9TygjjIdOhBBc= X-Google-Smtp-Source: ABdhPJwYZr8saZ1l0/26xD/I+LMdt9FzRCWubyN+UOi7ghTOrLlNcA6F9VTgZcmh0ysNN5b21EezDQ== X-Received: by 2002:a6b:1685:: with SMTP id 127mr15950564iow.135.1627322847362; Mon, 26 Jul 2021 11:07:27 -0700 (PDT) Received: from auth1-smtp.messagingengine.com (auth1-smtp.messagingengine.com. [66.111.4.227]) by smtp.gmail.com with ESMTPSA id a1sm264889ilp.1.2021.07.26.11.07.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 26 Jul 2021 11:07:26 -0700 (PDT) Received: from compute4.internal (compute4.nyi.internal [10.202.2.44]) by mailauth.nyi.internal (Postfix) with ESMTP id ED4CE27C0068; Mon, 26 Jul 2021 14:07:25 -0400 (EDT) Received: from mailfrontend1 ([10.202.2.162]) by compute4.internal (MEProxy); Mon, 26 Jul 2021 14:07:25 -0400 X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvtddrgeehgdduudejucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmne cujfgurhephffvufffkffojghfggfgsedtkeertdertddtnecuhfhrohhmpeeuohhquhhn ucfhvghnghcuoegsohhquhhnrdhfvghnghesghhmrghilhdrtghomheqnecuggftrfgrth htvghrnhephedvveetfefgiedutedtfeevvddvleekjeeuffffleeguefhhfejteekieeu ueelnecuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehmrghilhhfrhhomhepsg hoqhhunhdomhgvshhmthhprghuthhhphgvrhhsohhnrghlihhthidqieelvdeghedtieeg qddujeejkeehheehvddqsghoqhhunhdrfhgvnhhgpeepghhmrghilhdrtghomhesfhhigi hmvgdrnhgrmhgv X-ME-Proxy: Received: by mail.messagingengine.com (Postfix) with ESMTPA; Mon, 26 Jul 2021 14:07:25 -0400 (EDT) From: Boqun Feng To: Bjorn Helgaas , Arnd Bergmann , Marc Zyngier , Lorenzo Pieralisi Cc: Catalin Marinas , Will Deacon , "K. Y. Srinivasan" , Haiyang Zhang , Stephen Hemminger , Wei Liu , Dexuan Cui , Rob Herring , =?UTF-8?q?Krzysztof=20Wilczy=C5=84ski?= , Boqun Feng , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-pci@vger.kernel.org, Sunil Muthuswamy , Mike Rapoport Subject: [PATCH v6 4/8] arm64: PCI: Support root bridge preparation for Hyper-V Date: Tue, 27 Jul 2021 02:06:53 +0800 Message-Id: <20210726180657.142727-5-boqun.feng@gmail.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210726180657.142727-1-boqun.feng@gmail.com> References: <20210726180657.142727-1-boqun.feng@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently at root bridge preparation, the corresponding ACPI device will be set as the companion, however for a Hyper-V virtual PCI root bridge, there is no corresponding ACPI device, because a Hyper-V virtual PCI root bridge is discovered via VMBus rather than ACPI table. In order to support this, we need to make pcibios_root_bridge_prepare() work with cfg->parent being NULL. Use a NULL pointer as the ACPI device if there is no corresponding ACPI device, and this is fine because: 1) ACPI_COMPANION_SET() can work with the second parameter being NULL, 2) semantically, if a NULL pointer is set via ACPI_COMPANION_SET(), ACPI_COMPANION() (the read API for this field) will return NULL, and since ACPI_COMPANION() may return NULL, so users must have handled the cases where it returns NULL, and 3) since there is no corresponding ACPI device, it would be wrong to use any other value here. Signed-off-by: Boqun Feng --- arch/arm64/kernel/pci.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kernel/pci.c b/arch/arm64/kernel/pci.c index 5148ae242780..2276689b5411 100644 --- a/arch/arm64/kernel/pci.c +++ b/arch/arm64/kernel/pci.c @@ -90,7 +90,17 @@ int pcibios_root_bridge_prepare(struct pci_host_bridge *bridge) return 0; cfg = bridge->bus->sysdata; - adev = to_acpi_device(cfg->parent); + + /* + * On Hyper-V there is no corresponding ACPI device for a root bridge, + * therefore ->parent is set as NULL by the driver. And set 'adev' as + * NULL in this case because there is no proper ACPI device. + */ + if (!cfg->parent) + adev = NULL; + else + adev = to_acpi_device(cfg->parent); + bus_dev = &bridge->bus->dev; ACPI_COMPANION_SET(&bridge->dev, adev); -- 2.32.0