From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received-SPF: Pass (sender SPF authorized) identity=mailfrom; client-ip=134.134.136.20; helo=mga02.intel.com; envelope-from=ruiyu.ni@intel.com; receiver=edk2-devel@lists.01.org Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 971682205B93E for ; Wed, 17 Jan 2018 22:08:40 -0800 (PST) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 17 Jan 2018 22:14:01 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.46,376,1511856000"; d="scan'208";a="20334473" Received: from ray-dev.ccr.corp.intel.com ([10.239.9.19]) by orsmga003.jf.intel.com with ESMTP; 17 Jan 2018 22:14:00 -0800 From: Ruiyu Ni To: edk2-devel@lists.01.org Cc: Ming Shao Date: Thu, 18 Jan 2018 14:13:59 +0800 Message-Id: <20180118061359.351852-1-ruiyu.ni@intel.com> X-Mailer: git-send-email 2.15.1.windows.2 Subject: [PATCH] UefiCpuPkg/MtrrLib: Add comments to recommend to use batch-set API X-BeenThere: edk2-devel@lists.01.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: EDK II Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 18 Jan 2018 06:08:41 -0000 MtrrSetMemoryAttributesInMtrrSettings() is a batch-set API. When setting multiple ranges of memory attributes, the single-set API (MtrrSetMemoryAttributeInMtrrSettings and MtrrSetMemoryAttribute) may fail, but batch-set API may succeed. Add comments to recommend caller to use batch-set API when setting multiple ranges. Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Ruiyu Ni Cc: Ming Shao --- UefiCpuPkg/Include/Library/MtrrLib.h | 10 ++++++++++ UefiCpuPkg/Library/MtrrLib/MtrrLib.c | 10 ++++++++++ 2 files changed, 20 insertions(+) diff --git a/UefiCpuPkg/Include/Library/MtrrLib.h b/UefiCpuPkg/Include/Library/MtrrLib.h index d56f1057e1..f82c27ea0c 100644 --- a/UefiCpuPkg/Include/Library/MtrrLib.h +++ b/UefiCpuPkg/Include/Library/MtrrLib.h @@ -157,6 +157,11 @@ GetFirmwareVariableMtrrCount ( @retval RETURN_OUT_OF_RESOURCES There are not enough system resources to modify the attributes of the memory resource range. + Multiple memory range attributes setting by calling this API multiple + times may fail with status RETURN_OUT_OF_RESOURCES. It may not mean + the number of CPU MTRRs are too small to set such memory attributes. + Pass the multiple memory range attributes to one call of + MtrrSetMemoryAttributesInMtrrSettings() may succeed. @retval RETURN_BUFFER_TOO_SMALL The fixed internal scratch buffer is too small for MTRR calculation. Caller should use MtrrSetMemoryAttributesInMtrrSettings() to specify external scratch buffer. @@ -354,6 +359,11 @@ MtrrGetDefaultMemoryType ( BaseAddress and Length cannot be modified. @retval RETURN_OUT_OF_RESOURCES There are not enough system resources to modify the attributes of the memory resource range. + Multiple memory range attributes setting by calling this API multiple + times may fail with status RETURN_OUT_OF_RESOURCES. It may not mean + the number of CPU MTRRs are too small to set such memory attributes. + Pass the multiple memory range attributes to one call of + MtrrSetMemoryAttributesInMtrrSettings() may succeed. @retval RETURN_BUFFER_TOO_SMALL The fixed internal scratch buffer is too small for MTRR calculation. Caller should use MtrrSetMemoryAttributesInMtrrSettings() to specify external scratch buffer. diff --git a/UefiCpuPkg/Library/MtrrLib/MtrrLib.c b/UefiCpuPkg/Library/MtrrLib/MtrrLib.c index 2496d08ad4..dfce9a996b 100644 --- a/UefiCpuPkg/Library/MtrrLib/MtrrLib.c +++ b/UefiCpuPkg/Library/MtrrLib/MtrrLib.c @@ -2513,6 +2513,11 @@ Exit: BaseAddress and Length cannot be modified. @retval RETURN_OUT_OF_RESOURCES There are not enough system resources to modify the attributes of the memory resource range. + Multiple memory range attributes setting by calling this API multiple + times may fail with status RETURN_OUT_OF_RESOURCES. It may not mean + the number of CPU MTRRs are too small to set such memory attributes. + Pass the multiple memory range attributes to one call of + MtrrSetMemoryAttributesInMtrrSettings() may succeed. @retval RETURN_BUFFER_TOO_SMALL The fixed internal scratch buffer is too small for MTRR calculation. Caller should use MtrrSetMemoryAttributesInMtrrSettings() to specify external scratch buffer. @@ -2561,6 +2566,11 @@ MtrrSetMemoryAttributeInMtrrSettings ( @retval RETURN_OUT_OF_RESOURCES There are not enough system resources to modify the attributes of the memory resource range. + Multiple memory range attributes setting by calling this API multiple + times may fail with status RETURN_OUT_OF_RESOURCES. It may not mean + the number of CPU MTRRs are too small to set such memory attributes. + Pass the multiple memory range attributes to one call of + MtrrSetMemoryAttributesInMtrrSettings() may succeed. @retval RETURN_BUFFER_TOO_SMALL The fixed internal scratch buffer is too small for MTRR calculation. Caller should use MtrrSetMemoryAttributesInMtrrSettings() to specify external scratch buffer. -- 2.15.1.windows.2