From patchwork Tue Mar 1 10:56:07 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xiao Guangrong X-Patchwork-Id: 590462 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id BBD4414033B for ; Tue, 1 Mar 2016 21:57:13 +1100 (AEDT) Received: from localhost ([::1]:48519 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aahzL-0000aD-0h for incoming@patchwork.ozlabs.org; Tue, 01 Mar 2016 05:57:11 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49146) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aahyl-0007uT-O2 for qemu-devel@nongnu.org; Tue, 01 Mar 2016 05:56:36 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aahyh-0001Pg-IS for qemu-devel@nongnu.org; Tue, 01 Mar 2016 05:56:35 -0500 Received: from mga01.intel.com ([192.55.52.88]:12366) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aahyh-0001N1-E4 for qemu-devel@nongnu.org; Tue, 01 Mar 2016 05:56:31 -0500 Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga101.fm.intel.com with ESMTP; 01 Mar 2016 02:56:31 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.22,522,1449561600"; d="scan'208";a="57509776" Received: from xiaoreal1.sh.intel.com (HELO xiaoreal1.sh.intel.com.sh.intel.com) ([10.239.48.79]) by fmsmga004.fm.intel.com with ESMTP; 01 Mar 2016 02:56:29 -0800 From: Xiao Guangrong To: pbonzini@redhat.com, imammedo@redhat.com Date: Tue, 1 Mar 2016 18:56:07 +0800 Message-Id: <1456829771-71553-6-git-send-email-guangrong.xiao@linux.intel.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1456829771-71553-1-git-send-email-guangrong.xiao@linux.intel.com> References: <1456829771-71553-1-git-send-email-guangrong.xiao@linux.intel.com> X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 192.55.52.88 Cc: Xiao Guangrong , ehabkost@redhat.com, kvm@vger.kernel.org, mst@redhat.com, gleb@kernel.org, mtosatti@redhat.com, qemu-devel@nongnu.org, stefanha@redhat.com, dan.j.williams@intel.com, rth@twiddle.net Subject: [Qemu-devel] [PATCH 5/9] acpi: add build_append_named_dword, returning an offset in buffer X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org From: "Michael S. Tsirkin" This is a very limited form of support for runtime patching - similar in functionality to what we can do with ACPI_EXTRACT macros in python, but implemented in C. This is to allow ACPI code direct access to data tables - which is exactly what DataTableRegion is there for, except no known windows release so far implements DataTableRegion. Signed-off-by: Michael S. Tsirkin Signed-off-by: Xiao Guangrong --- hw/acpi/aml-build.c | 28 ++++++++++++++++++++++++++++ include/hw/acpi/aml-build.h | 3 +++ 2 files changed, 31 insertions(+) diff --git a/hw/acpi/aml-build.c b/hw/acpi/aml-build.c index f26fa26..ab89ca6 100644 --- a/hw/acpi/aml-build.c +++ b/hw/acpi/aml-build.c @@ -258,6 +258,34 @@ static void build_append_int(GArray *table, uint64_t value) } } +/* + * Build NAME(XXXX, 0x00000000) where 0x00000000 is encoded as a dword, + * and return the offset to 0x00000000 for runtime patching. + * + * Warning: runtime patching is best avoided. Only use this as + * a replacement for DataTableRegion (for guests that don't + * support it). + */ +int +build_append_named_dword(GArray *array, const char *name_format, ...) +{ + int offset; + va_list ap; + + build_append_byte(array, 0x08); /* NameOp */ + va_start(ap, name_format); + build_append_namestringv(array, name_format, ap); + va_end(ap); + + build_append_byte(array, 0x0C); /* DWordPrefix */ + + offset = array->len; + build_append_int_noprefix(array, 0x00000000, 4); + assert(array->len == offset + 4); + + return offset; +} + static GPtrArray *alloc_list; static Aml *aml_alloc(void) diff --git a/include/hw/acpi/aml-build.h b/include/hw/acpi/aml-build.h index 07b2d48..7404e2a 100644 --- a/include/hw/acpi/aml-build.h +++ b/include/hw/acpi/aml-build.h @@ -370,4 +370,7 @@ void build_rsdt(GArray *table_data, GArray *linker, GArray *table_offsets, const char *oem_id, const char *oem_table_id); +int +build_append_named_dword(GArray *array, const char *name_format, ...); + #endif