From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: mx.groups.io; dkim=missing; spf=fail (domain: intel.com, ip: , mailfrom: hao.a.wu@intel.com) Received: from mga05.intel.com (mga05.intel.com []) by groups.io with SMTP; Tue, 23 Apr 2019 01:06:38 -0700 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga105.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 23 Apr 2019 01:06:37 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.60,385,1549958400"; d="scan'208";a="339945777" Received: from shwdeopenpsi014.ccr.corp.intel.com ([10.239.9.8]) by fmsmga006.fm.intel.com with ESMTP; 23 Apr 2019 01:06:33 -0700 From: "Wu, Hao A" To: devel@edk2.groups.io Cc: Hao Wu , Ray Ni , Eric Dong , Jian J Wang Subject: [PATCH v3 1/2] MdeModulePkg/AhciPei: Limit max transfer blocknum for 48-bit address Date: Tue, 23 Apr 2019 16:06:29 +0800 Message-Id: <20190423080630.14992-2-hao.a.wu@intel.com> X-Mailer: git-send-email 2.12.0.windows.1 In-Reply-To: <20190423080630.14992-1-hao.a.wu@intel.com> References: <20190423080630.14992-1-hao.a.wu@intel.com> REF:https://bugzilla.tianocore.org/show_bug.cgi?id=1483 Due to the limited resource on the VTd DMA buffer size in the PEI phase, the driver will limit the maximum transfer block number for 48-bit addressing. According to PCDs: gIntelSiliconPkgTokenSpaceGuid.PcdVTdPeiDmaBufferSize|0x00400000 gIntelSiliconPkgTokenSpaceGuid.PcdVTdPeiDmaBufferSizeS3|0x00200000 The default buffer size allocated for IOMMU mapping is: * 4M bytes for non-S3 cases; * 2M bytes for S3 For ATA devices in 48-bit address mode, the maximum block number is currently set to 0xFFFF. For a device with block size equal to 512 bytes, the maximum buffer allowed for mapping within AhciPei driver will be close to 32M bytes. Thus, this commit will limit the 48-bit mode maximum block number to 0x800, which means 1M-byte maximum buffer for mapping when the block size of a device is 512 bytes. By doing so, potential failure on calls to the IOMMU 'Map' service can be avoided. Cc: Ray Ni Cc: Eric Dong Cc: Jian J Wang Signed-off-by: Hao Wu --- MdeModulePkg/Bus/Ata/AhciPei/AhciMode.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/MdeModulePkg/Bus/Ata/AhciPei/AhciMode.c b/MdeModulePkg/Bus/Ata/AhciPei/AhciMode.c index a83c213a47..11754b3057 100644 --- a/MdeModulePkg/Bus/Ata/AhciPei/AhciMode.c +++ b/MdeModulePkg/Bus/Ata/AhciPei/AhciMode.c @@ -48,7 +48,13 @@ UINT8 mAtaTrustCommands[2] = { // Look up table (Lba48Bit) for maximum transfer block number // #define MAX_28BIT_TRANSFER_BLOCK_NUM 0x100 -#define MAX_48BIT_TRANSFER_BLOCK_NUM 0xFFFF +// +// Due to limited resource for VTd PEI DMA buffer on platforms, the driver +// limits the maximum transfer block number for 48-bit addressing. +// Here, setting to 0x800 means that for device with 512-byte block size, the +// maximum buffer for DMA mapping will be 1M bytes in size. +// +#define MAX_48BIT_TRANSFER_BLOCK_NUM 0x800 UINT32 mMaxTransferBlockNumber[2] = { MAX_28BIT_TRANSFER_BLOCK_NUM, -- 2.12.0.windows.1