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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 3D08EC3DA7F for ; Wed, 31 Jul 2024 19:51:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:References: List-Owner; bh=ihD/LEs/logEkV+J3vyfzX5JPn9I21iQNuhURGCNnbQ=; b=ijFdyJiZqWVWLw 5vQNEpi1wcBt34DnAIO1lCsHuOP7854fgg/XOw1AdF41nPFGZboxXX7AjZdvi1m2A3trYNpC7/7xo QbenEceZhTbLavZ3EW75eGvR/k+8+u0U/cvLIxUKJaVAoyhrW0ARet+0FSIVZF4RpRpHSAr9wnJX8 p3sxiO+trIGmTBTvL+3aMKtj2j048vI7sIP8rrZOyq/65ZcaGTz0RLlYC3ElLbgQXg0XCKCPdwRu0 5uS+IBV8xwXo7xIzZ3pp3CHqFagXr0LFXM0WSczgAVNRXT73GkSj0vkbKOd4dn3C07Fk61thxCeGo KD5MaANaxBMVqA6Fs3zw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sZFLo-00000002Mvg-0zxu; Wed, 31 Jul 2024 19:51:08 +0000 Received: from sin.source.kernel.org ([145.40.73.55]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sZFKF-00000002MEU-3B7T; Wed, 31 Jul 2024 19:49:34 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sin.source.kernel.org (Postfix) with ESMTP id 07E74CE17D1; Wed, 31 Jul 2024 19:49:30 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 118DEC4AF09; Wed, 31 Jul 2024 19:49:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1722455369; bh=PUpvq4IvGstISJBnqSrlDq4K2g9I2Ugc4NXAsXQFQ+Y=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=FzwcgcEJ2HxUeoOcvMsJeNsPl6w9Kj08seE75vXEQtKYVaw9J5f5kGITSMChJ5ngg nyOup++1xb53SaOvf2JQ6WZNlC0k9CcImr85jS76aolvFVD1FC92psCq2PvJTtVh43 JSm+TZmXzo9IqPIorv/zUDNb7zcBKywFNjDBjzOenBlkIy7+dBWQj4PvcAIYmwZWJd mnRfyHxi402vgsIw2XNgcy189EIbANEqBOYCgpV2Nbwbgkc9WXc2wGBBi/g4AHzyUm adI7kyJrsRNPmnjJPx8nunXdyVHshIdNVxYRsg7P4rs98iTyg7W80qr3kqBAvFNRer 5IIcm7AENs1qQ== Date: Wed, 31 Jul 2024 14:49:27 -0500 From: Bjorn Helgaas To: Sunil V L Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-riscv@lists.infradead.org, linux-pci@vger.kernel.org, Catalin Marinas , Will Deacon , Palmer Dabbelt , Albert Ou , "Rafael J . Wysocki" , Len Brown , Bjorn Helgaas , Anup Patel , Thomas Gleixner , Samuel Holland , Robert Moore , Conor Dooley , Andrew Jones , Haibo Xu , Atish Kumar Patra , Drew Fustini Subject: Re: [PATCH v7 08/17] ACPI: pci_link: Clear the dependencies after probe Message-ID: <20240731194927.GA78106@bhelgaas> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240729142241.733357-9-sunilvl@ventanamicro.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240731_124932_682387_6C1A099E X-CRM114-Status: GOOD ( 21.20 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Jul 29, 2024 at 07:52:30PM +0530, Sunil V L wrote: > RISC-V platforms need to use dependencies between PCI host bridge, Link > devices and the interrupt controllers to ensure probe order. The > dependency is like below. > > Interrupt controller <-- Link Device <-- PCI Host bridge. > > If there is no dependency added between Link device and PCI Host Bridge, > then the PCI end points can get probed prior to link device, unable to > get mapping for INTx. This sentence is missing a word or something. Maybe it's supposed to say something like this: If there is no dependency between Link device and PCI Host Bridge, then PCI devices may be probed prior to Link devices. If a PCI device is probed before its Link device, we won't be able to find its INTx mapping. > So, add the link device's HID to dependency honor list and also clear it > after its probe. It looks like *this* patch only clears it after probe. And the commit log doesn't say why we need to clear the dependency. > Signed-off-by: Sunil V L > --- > drivers/acpi/pci_link.c | 2 ++ > drivers/acpi/scan.c | 1 + > 2 files changed, 3 insertions(+) > > diff --git a/drivers/acpi/pci_link.c b/drivers/acpi/pci_link.c > index aa1038b8aec4..b727db968f33 100644 > --- a/drivers/acpi/pci_link.c > +++ b/drivers/acpi/pci_link.c > @@ -748,6 +748,8 @@ static int acpi_pci_link_add(struct acpi_device *device, > if (result) > kfree(link); > > + acpi_dev_clear_dependencies(device); > + > return result < 0 ? result : 1; > } > > diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c > index 28a221f956d7..753539a1f26b 100644 > --- a/drivers/acpi/scan.c > +++ b/drivers/acpi/scan.c > @@ -863,6 +863,7 @@ static const char * const acpi_honor_dep_ids[] = { > "INTC10CF", /* IVSC (MTL) driver must be loaded to allow i2c access to camera sensors */ > "RSCV0001", /* RISC-V PLIC */ > "RSCV0002", /* RISC-V APLIC */ > + "PNP0C0F", /* PCI Link Device */ > NULL > }; > > -- > 2.43.0 >