From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andy Shevchenko Date: Fri, 21 Jul 2017 22:32:06 +0300 Subject: [U-Boot] [PATCH v1 7/7] x86: acpi: Don't touch hardware on HW reduced platforms In-Reply-To: <20170721193206.586-1-andriy.shevchenko@linux.intel.com> References: <20170721193206.586-1-andriy.shevchenko@linux.intel.com> Message-ID: <20170721193206.586-8-andriy.shevchenko@linux.intel.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de If ACPI HW reduced bit in FADT is set we should ignore any ACPI hardware communications. Signed-off-by: Andy Shevchenko --- arch/x86/lib/acpi_table.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/x86/lib/acpi_table.c b/arch/x86/lib/acpi_table.c index da6014fb41..3eb101105b 100644 --- a/arch/x86/lib/acpi_table.c +++ b/arch/x86/lib/acpi_table.c @@ -463,6 +463,10 @@ ulong write_acpi_tables(ulong start) debug("ACPI: done\n"); + /* Don't touch ACPI hardware on HW reduced platforms */ + if (fadt->flags & ACPI_FADT_HW_REDUCED_ACPI) + return current; + /* * Other than waiting for OSPM to request us to switch to ACPI mode, * do it by ourselves, since SMI will not be triggered. -- 2.13.2