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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8A538C43334 for ; Wed, 6 Jul 2022 10:43:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231867AbiGFKn1 (ORCPT ); Wed, 6 Jul 2022 06:43:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56682 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230231AbiGFKnY (ORCPT ); Wed, 6 Jul 2022 06:43:24 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A1654390; Wed, 6 Jul 2022 03:43:23 -0700 (PDT) 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 3CE9261E52; Wed, 6 Jul 2022 10:43:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 44AFFC341CF; Wed, 6 Jul 2022 10:43:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1657104202; bh=99roP7FFejJ4tHZj9bNwClVKU/G2TunICeiuDt+0hYc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=vQVM0JvSni/qmtb+vV+CpQPqbeOyFsnWG3Osw+0Th+vK0NqSLNKg+N1qsBudC9ccb cCZ2YrwQAYFsrTq9VEN8H2e2K6v0QKaEDScGQrAOaqqnXx57l3ojtapiADZ7q90+Ln T4KMscRZBU8hOiU7q2FeOsJgN3hDSngSltLiaPyKTvOgl1KGnDVV8fe3re8/KjKIav XazxYK7Vw8oYOmPduyKSsQXUnTBK8JhhnfjOWlf8kEm3X5ZSQD8WPpJyX2pjN6e5GN sDVbJeWHQXZaii7lpmvq8RkBt/HAgKKR+XtutdUZLigIiwvNbj03i1my8lGmxsAGvw oHLpDcT7KVP7w== Received: by pali.im (Postfix) id EFA197BA; Wed, 6 Jul 2022 12:43:21 +0200 (CEST) From: =?UTF-8?q?Pali=20Roh=C3=A1r?= To: Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras , Christophe Leroy , =?UTF-8?q?C=C3=A9dric=20Le=20Goater?= , Nick Child , Bjorn Helgaas Cc: linuxppc-dev@lists.ozlabs.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 5/5] powerpc/pci: Add config option for using all 256 PCI buses Date: Wed, 6 Jul 2022 12:43:08 +0200 Message-Id: <20220706104308.5390-6-pali@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20220706104308.5390-1-pali@kernel.org> References: <20220706104308.5390-1-pali@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org By default on PPC32 are PCI bus numbers unique across all PCI domains. So system could have only 256 PCI buses independently of available PCI domains. This is due to filling DT property pci-OF-bus-map which does not reflect multi-domain setup. On all powerpc platforms except chrp and powermac there is no DT property pci-OF-bus-map anymore and therefore it is possible on non-chrp/powermac platforms to avoid this limitation of maximal number of 256 PCI buses in system even on multi-domain setup. But avoiding this limitation would mean that all PCI and PCIe devices would be present on completely different BDF addresses as every PCI domain starts numbering PCI bueses from zero (instead of the last bus number of previous enumerated PCI domain). Such change could break existing software which expects fixed PCI bus numbers. So add a new config option CONFIG_PPC_PCI_BUS_NUM_DOMAIN_DEPENDENT which enables this change. By default it is disabled. It cause that initial value of hose->first_busno is zero. Signed-off-by: Pali Rohár --- arch/powerpc/Kconfig | 11 +++++++++++ arch/powerpc/kernel/pci_32.c | 6 ++++++ 2 files changed, 17 insertions(+) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index be68c1f02b79..f66084bc1dfe 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -370,6 +370,17 @@ config PPC_DCR depends on PPC_DCR_NATIVE || PPC_DCR_MMIO default y +config PPC_PCI_BUS_NUM_DOMAIN_DEPENDENT + depends on PPC32 + depends on !PPC_PMAC && !PPC_CHRP + bool "Assign PCI bus numbers from zero individually for each PCI domain" + help + By default on PPC32 were PCI bus numbers unique across all PCI domains. + So system could have only 256 PCI buses independently of available + PCI domains. When this option is enabled then PCI bus numbers are + PCI domain dependent and each PCI controller on own domain can have + 256 PCI buses, like it is on other Linux architectures. + config PPC_OF_PLATFORM_PCI bool depends on PCI diff --git a/arch/powerpc/kernel/pci_32.c b/arch/powerpc/kernel/pci_32.c index 2f7284b68f06..433965bf37b4 100644 --- a/arch/powerpc/kernel/pci_32.c +++ b/arch/powerpc/kernel/pci_32.c @@ -239,7 +239,9 @@ void pcibios_setup_phb_io_space(struct pci_controller *hose) static int __init pcibios_init(void) { struct pci_controller *hose, *tmp; +#ifndef CONFIG_PPC_PCI_BUS_NUM_DOMAIN_DEPENDENT int next_busno = 0; +#endif printk(KERN_INFO "PCI: Probing PCI hardware\n"); @@ -248,13 +250,17 @@ static int __init pcibios_init(void) /* Scan all of the recorded PCI controllers. */ list_for_each_entry_safe(hose, tmp, &hose_list, list_node) { +#ifndef CONFIG_PPC_PCI_BUS_NUM_DOMAIN_DEPENDENT if (pci_assign_all_buses) hose->first_busno = next_busno; +#endif hose->last_busno = 0xff; pcibios_scan_phb(hose); pci_bus_add_devices(hose->bus); +#ifndef CONFIG_PPC_PCI_BUS_NUM_DOMAIN_DEPENDENT if (pci_assign_all_buses || next_busno <= hose->last_busno) next_busno = hose->last_busno + pcibios_assign_bus_offset; +#endif } #if defined(CONFIG_PPC_PMAC) || defined(CONFIG_PPC_CHRP) -- 2.20.1