From patchwork Wed Jul 14 12:50:14 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Geert Uytterhoeven X-Patchwork-Id: 12376855 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 771FDC07E9A for ; Wed, 14 Jul 2021 12:50:50 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id D8B93613D0 for ; Wed, 14 Jul 2021 12:50:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D8B93613D0 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=glider.be Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 01DE26B0085; Wed, 14 Jul 2021 08:50:50 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 010466B0083; Wed, 14 Jul 2021 08:50:49 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id DA5086B008C; Wed, 14 Jul 2021 08:50:49 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0031.hostedemail.com [216.40.44.31]) by kanga.kvack.org (Postfix) with ESMTP id B77336B0083 for ; Wed, 14 Jul 2021 08:50:49 -0400 (EDT) Received: from smtpin39.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id B2D0E18598422 for ; Wed, 14 Jul 2021 12:50:48 +0000 (UTC) X-FDA: 78361177776.39.99A42DE Received: from xavier.telenet-ops.be (xavier.telenet-ops.be [195.130.132.52]) by imf04.hostedemail.com (Postfix) with ESMTP id F08B050000AC for ; Wed, 14 Jul 2021 12:50:47 +0000 (UTC) Received: from ramsan.of.borg ([IPv6:2a02:1810:ac12:ed10:39cc:190a:2775:cfe7]) by xavier.telenet-ops.be with bizsmtp id V0qX250091ccfby010qX5Y; Wed, 14 Jul 2021 14:50:46 +0200 Received: from rox.of.borg ([192.168.97.57]) by ramsan.of.borg with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1m3eLO-0018dP-Vb; Wed, 14 Jul 2021 14:50:30 +0200 Received: from geert by rox.of.borg with local (Exim 4.93) (envelope-from ) id 1m3eLN-00AaEC-PF; Wed, 14 Jul 2021 14:50:29 +0200 From: Geert Uytterhoeven To: Rob Herring , Russell King , Nicolas Pitre , Ard Biesheuvel , Linus Walleij , Catalin Marinas , Will Deacon , Nick Kossifidis , Paul Walmsley , Palmer Dabbelt , Albert Ou , Frank Rowand , Dave Young , Mike Rapoport Cc: Baoquan He , Vivek Goyal , Andrew Morton , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-riscv@lists.infradead.org, kexec@lists.infradead.org, linux-mm@kvack.org, linux-renesas-soc@vger.kernel.org, linux-kernel@vger.kernel.org, Geert Uytterhoeven Subject: [PATCH v4 04/10] of: fdt: Add generic support for parsing usable memory range property Date: Wed, 14 Jul 2021 14:50:14 +0200 Message-Id: <4064ea598a10ea0a4b9043aa771bcea1a00efac3.1626266516.git.geert+renesas@glider.be> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 Authentication-Results: imf04.hostedemail.com; dkim=none; spf=none (imf04.hostedemail.com: domain of geert@linux-m68k.org has no SPF policy when checking 195.130.132.52) smtp.mailfrom=geert@linux-m68k.org; dmarc=none X-Rspamd-Server: rspam05 X-Stat-Signature: bcxuzf91t16je996dujmzjysirdxrtww X-Rspamd-Queue-Id: F08B050000AC X-HE-Tag: 1626267047-552538 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Add support for parsing the "linux,usable-memory-range" property in the "/chosen" node to the FDT core code. This can co-exist safely with the architecture-specific parsing, until the latter has been removed. Architecture-specific code still has to make sure the resulting memory range limitation is applied, if present. Signed-off-by: Geert Uytterhoeven --- About the change to chosen.txt: I have a similar change for schemas/chosen.yaml in dt-schema. v4: - New. --- Documentation/devicetree/bindings/chosen.txt | 6 ++--- drivers/of/fdt.c | 24 ++++++++++++++++++++ 2 files changed, 27 insertions(+), 3 deletions(-) diff --git a/Documentation/devicetree/bindings/chosen.txt b/Documentation/devicetree/bindings/chosen.txt index 5b0b94eb2d04e79d..1cc3aa10dcb10588 100644 --- a/Documentation/devicetree/bindings/chosen.txt +++ b/Documentation/devicetree/bindings/chosen.txt @@ -79,9 +79,9 @@ a different secondary CPU release mechanism) linux,usable-memory-range ------------------------- -This property (arm64 only) holds a base address and size, describing a -limited region in which memory may be considered available for use by -the kernel. Memory outside of this range is not available for use. +This property holds a base address and size, describing a limited region in +which memory may be considered available for use by the kernel. Memory outside +of this range is not available for use. This property describes a limitation: memory within this range is only valid when also described through another mechanism that the kernel diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index f797d52c5b492cb7..1b4dd5418b44b9fb 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -935,6 +935,29 @@ static void __init early_init_dt_check_for_elfcorehdr(unsigned long node) elfcorehdr_addr, elfcorehdr_size); } +/** + * early_init_dt_check_for_usable_mem_range - Decode usable memory range + * location from flat tree + * @node: reference to node containing usable memory range location ('chosen') + */ +static void __init early_init_dt_check_for_usable_mem_range(unsigned long node) +{ + const __be32 *prop; + int len; + + pr_debug("Looking for usable-memory-range property... "); + + prop = of_get_flat_dt_prop(node, "linux,usable-memory-range", &len); + if (!prop || (len < (dt_root_addr_cells + dt_root_size_cells))) + return; + + cap_mem_addr = dt_mem_next_cell(dt_root_addr_cells, &prop); + cap_mem_size = dt_mem_next_cell(dt_root_size_cells, &prop); + + pr_debug("cap_mem_start=%pa cap_mem_size=%pa\n", &cap_mem_addr, + &cap_mem_size); +} + #ifdef CONFIG_SERIAL_EARLYCON int __init early_init_dt_scan_chosen_stdout(void) @@ -1083,6 +1106,7 @@ int __init early_init_dt_scan_chosen(unsigned long node, const char *uname, early_init_dt_check_for_initrd(node); early_init_dt_check_for_elfcorehdr(node); + early_init_dt_check_for_usable_mem_range(node); /* Retrieve command line */ p = of_get_flat_dt_prop(node, "bootargs", &l);