From 4d83ee04f44a8dc9e6425a719b39c9d378730ca1 Mon Sep 17 00:00:00 2001 From: Edward Pickup Date: Wed, 20 Jul 2022 16:59:49 +0800 Subject: ShellPkg: Add revision check for DSDT Header on Arm Bugzilla: 3995 (https://bugzilla.tianocore.org/show_bug.cgi?id=3995) ACPI 6.4 spec states that if the revision field in the DSDT header is less than 2, then all integers are restricted in width to 32 bits, including in SSDTs. Arm Base boot requirements state that platforms must conform to ACPI 6.3 or later, and that legacy tables are not supported. Adds a check for this field and raise warning if revision is less than 2 on arm. Signed-off-by: Edward Pickup Reviewed-by: Zhichao Gao --- .../Parsers/Dsdt/DsdtParser.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) (limited to 'ShellPkg') diff --git a/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Dsdt/DsdtParser.c b/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Dsdt/DsdtParser.c index e75e462223..7f30a8409b 100644 --- a/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Dsdt/DsdtParser.c +++ b/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Dsdt/DsdtParser.c @@ -1,7 +1,7 @@ /** @file DSDT table parser - Copyright (c) 2016 - 2018, ARM Limited. All rights reserved. + Copyright (c) 2016 - 2022, ARM Limited. All rights reserved. SPDX-License-Identifier: BSD-2-Clause-Patent @par Reference(s): @@ -39,4 +39,20 @@ ParseAcpiDsdt ( } DumpAcpiHeader (Ptr); + + // As per 19.6.29 in the version 6.4 of the ACPI spec, a revision less than 2 + // restricts integers to 32 bit width. This may not be intended, raise a + // warning + #if defined (MDE_CPU_AARCH64) || defined (MDE_CPU_ARM) + if (AcpiTableRevision < 2) { + IncrementWarningCount (); + Print ( + L"WARNING: DSDT Table Revision less than 2. Integer width restricted to " + L"32 bits. Table Revision = %d.\n", + AcpiTableRevision + ); + return; + } + + #endif } -- cgit v1.2.3