From patchwork Thu Feb 3 19:31:24 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Robin Murphy X-Patchwork-Id: 12734587 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 05C39C433F5 for ; Thu, 3 Feb 2022 19:31:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230467AbiBCTbd (ORCPT ); Thu, 3 Feb 2022 14:31:33 -0500 Received: from foss.arm.com ([217.140.110.172]:39608 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240903AbiBCTbb (ORCPT ); Thu, 3 Feb 2022 14:31:31 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5FF18147A; Thu, 3 Feb 2022 11:31:31 -0800 (PST) Received: from e121345-lin.cambridge.arm.com (e121345-lin.cambridge.arm.com [10.1.196.40]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 750943F774; Thu, 3 Feb 2022 11:31:30 -0800 (PST) From: Robin Murphy To: lorenzo.pieralisi@arm.com, guohanjun@huawei.com, sudeep.holla@arm.com Cc: linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Michael Petlan Subject: [PATCH v2] ACPI/IORT: Check node revision for PMCG resources Date: Thu, 3 Feb 2022 19:31:24 +0000 Message-Id: <75628ae41c257fb73588f7bf1c4459160e04be2b.1643916258.git.robin.murphy@arm.com> X-Mailer: git-send-email 2.28.0.dirty MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org The original version of the IORT PMCG definition had an oversight wherein there was no way to describe the second register page for an implementation using the recommended RELOC_CTRS feature. Although the spec was fixed, and the final patches merged to ACPICA and Linux written against the new version, it seems that some old firmware based on the original revision has survived and turned up in the wild. Add a check for the original PMCG definition, and avoid filling in the second memory resource with nonsense if so. Otherwise it is likely that something horrible will happen when the PMCG driver attempts to probe. Reported-by: Michael Petlan Fixes: 24e516049360 ("ACPI/IORT: Add support for PMCG") Signed-off-by: Robin Murphy Acked-by: Lorenzo Pieralisi --- v2: Simpler workaround, since I realised platform_get_resource() should happily just skip over a zero-initialised hole in the resource array. drivers/acpi/arm64/iort.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c index 175397913be1..7092b94b2aae 100644 --- a/drivers/acpi/arm64/iort.c +++ b/drivers/acpi/arm64/iort.c @@ -1371,9 +1371,17 @@ static void __init arm_smmu_v3_pmcg_init_resources(struct resource *res, res[0].start = pmcg->page0_base_address; res[0].end = pmcg->page0_base_address + SZ_4K - 1; res[0].flags = IORESOURCE_MEM; - res[1].start = pmcg->page1_base_address; - res[1].end = pmcg->page1_base_address + SZ_4K - 1; - res[1].flags = IORESOURCE_MEM; + /* + * The initial version in DEN0049C lacked a way to describe register + * page 1, which makes it broken for most PMCG implementations; in + * that case, just let the driver fail gracefully if it expects to + * find a second memory resource. + */ + if (node->revision > 0) { + res[1].start = pmcg->page1_base_address; + res[1].end = pmcg->page1_base_address + SZ_4K - 1; + res[1].flags = IORESOURCE_MEM; + } if (pmcg->overflow_gsiv) acpi_iort_register_irq(pmcg->overflow_gsiv, "overflow",