On 25 March 2017 at 09:28, Jiewen Yao <jiewen....@intel.com> wrote: > This protocol is to abstract IOMMU access. > > Cc: Ruiyu Ni <ruiyu...@intel.com> > Cc: Leo Duran <leo.du...@amd.com> > Cc: Brijesh Singh <brijesh.si...@amd.com> > Contributed-under: TianoCore Contribution Agreement 1.0 > Signed-off-by: Jiewen Yao <jiewen....@intel.com>
Hello all, It would be very useful for a IOMMU protocol such as this one to support non-identity mappings between the host and the PCI bus. On 64-bit ARM systems, no RAM may exist below 4 GB, and if a IOMMU is available, it could be used to remap RAM for DMA in a way that makes it 32-bit addressable for PCI masters that are not 64-bit capable. The PCI protocols in UEFI already allow such non-identity mappings. If a IOMMU protocol is introduced, it makes sense to allow it to be involved in establishing the device address when performing a map operation. -- Ard. > --- > MdeModulePkg/Include/Protocol/IoMmu.h | 132 ++++++++++++++++++++ > MdeModulePkg/MdeModulePkg.dec | 3 + > 2 files changed, 135 insertions(+) > > diff --git a/MdeModulePkg/Include/Protocol/IoMmu.h > b/MdeModulePkg/Include/Protocol/IoMmu.h > new file mode 100644 > index 0000000..55b9c78 > --- /dev/null > +++ b/MdeModulePkg/Include/Protocol/IoMmu.h > @@ -0,0 +1,132 @@ > +/** @file > + EFI IOMMU Protocol. > + > +Copyright (c) 2017, Intel Corporation. All rights reserved.<BR> > +This program and the accompanying materials are licensed and made available > under > +the terms and conditions of the BSD License that accompanies this > distribution. > +The full text of the license may be found at > +http://opensource.org/licenses/bsd-license.php. > + > +THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, > +WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. > + > +**/ > + > + > +#ifndef __IOMMU_H__ > +#define __IOMMU_H__ > + > +// > +// IOMMU Protocol GUID value > +// > +#define EDKII_IOMMU_PROTOCOL_GUID \ > + { \ > + 0x4e939de9, 0xd948, 0x4b0f, { 0x88, 0xed, 0xe6, 0xe1, 0xce, 0x51, > 0x7c, 0x1e } \ > + } > + > +// > +// Forward reference for pure ANSI compatability > +// > +typedef struct _EDKII_IOMMU_PROTOCOL EDKII_IOMMU_PROTOCOL; > + > +// > +// Revision The revision to which the IOMMU interface adheres. > +// All future revisions must be backwards compatible. > +// If a future version is not back wards compatible it is not the > same GUID. > +// > +#define EDKII_IOMMU_PROTOCOL_REVISION 0x00010000 > + > +// > +// IOMMU attribute. > +// These types can be "ORed" together as needed. > +// Any undefined bits are reserved and must be zero. > +// > +#define EDKII_IOMMU_ATTRIBUTE_READ 0x1 > +#define EDKII_IOMMU_ATTRIBUTE_WRITE 0x2 > + > +/** > + Set IOMMU attribute for a system memory. > + > + If the IOMMU protocol exists, the system memory cannot be used > + for DMA by default. > + > + When a device requests a DMA access for a system memory, > + the device driver need use SetAttribute() to update the IOMMU > + attribute to request DMA access (read and/or write). > + > + The DeviceHandle is used to identify which device it is. > + The IOMMU implementation need translate the device path to an IOMMU device > ID, > + and set IOMMU hardware register accordingly. > + 1) DeviceHandle can be a standard PCI device. > + The memory for BusMasterRead need set EDKII_IOMMU_ATTRIBUTE_READ. > + The memory for BusMasterWrite need set EDKII_IOMMU_ATTRIBUTE_WRITE. > + The memory for BusMasterCommonBuffer need set > EDKII_IOMMU_ATTRIBUTE_READ|EDKII_IOMMU_ATTRIBUTE_WRITE. > + After the memory is used, the memory need set 0 to keep it being > protected. > + 2) DeviceHandle can be an ACPI device (ISA, I2C, SPI, etc). > + The memory for DMA access need set EDKII_IOMMU_ATTRIBUTE_READ and/or > EDKII_IOMMU_ATTRIBUTE_WRITE. > + > + @param This The protocol instance pointer. > + @param DeviceHandle The device who initiates the DMA access request. > + @param BaseAddress The base of system memory address to be used as > the DMA memory. > + @param Length The length of system memory address to be used > as the DMA memory. > + @param IoMmuAttribute The IOMMU attribute. > + > + @retval EFI_SUCCESS The IoMmuAttribute is set for the memory > range specified by BaseAddress and Length. > + @retval EFI_INVALID_PARAMETER DeviceHandle is an invalid handle. > + @retval EFI_INVALID_PARAMETER BaseAddress is not IoMmu Page size aligned. > + @retval EFI_INVALID_PARAMETER Length is not IoMmu Page size aligned. > + @retval EFI_INVALID_PARAMETER Length is 0. > + @retval EFI_INVALID_PARAMETER IoMmuAttribute specified an illegal > combination of attributes. > + @retval EFI_UNSUPPORTED DeviceHandle is unknown by the IOMMU. > + @retval EFI_UNSUPPORTED The bit mask of IoMmuAttribute is not > supported by the IOMMU. > + @retval EFI_UNSUPPORTED The IOMMU does not support the memory range > specified by BaseAddress and Length. > + @retval EFI_OUT_OF_RESOURCES There are not enough resources available to > modify the IOMMU attribute. > + @retval EFI_DEVICE_ERROR The IOMMU device reported an error while > attempting the operation. > + > +**/ > +typedef > +EFI_STATUS > +(EFIAPI *EDKII_IOMMU_SET_ATTRIBUTE)( > + IN EDKII_IOMMU_PROTOCOL *This, > + IN EFI_HANDLE DeviceHandle, > + IN UINT64 BaseAddress, > + IN UINT64 Length, > + IN UINT64 IoMmuAttribute > + ); > + > +/** > + Get IOMMU page size. > + > + This is the minimal supported page size for a IOMMU. > + For example, if an IOMMU supports 4KiB, 2MiB and 1GiB, > + 4KiB should be returned. > + > + @param This Protocol instance pointer. > + @param PageSize The minimal supported page size for a IOMMU. > + > + @retval EFI_SUCCESS The page size is returned. > + @retval EFI_INVALID_PARAMETER PageSize is NULL. > + > +**/ > +typedef > +EFI_STATUS > +(EFIAPI *EDKII_IOMMU_GET_PAGE_SIZE)( > + IN EDKII_IOMMU_PROTOCOL *This, > + OUT UINTN *PageSize > + ); > + > +/// > +/// IOMMU Protocol structure. > +/// > +struct _EDKII_IOMMU_PROTOCOL { > + UINT64 Revision; > + EDKII_IOMMU_GET_PAGE_SIZE GetPageSize; > + EDKII_IOMMU_SET_ATTRIBUTE SetAttribute; > +}; > + > +/// > +/// IOMMU Protocol GUID variable. > +/// > +extern EFI_GUID gEdkiiIoMmuProtocolGuid; > + > +#endif > diff --git a/MdeModulePkg/MdeModulePkg.dec b/MdeModulePkg/MdeModulePkg.dec > index 356b3e1..db596b6 100644 > --- a/MdeModulePkg/MdeModulePkg.dec > +++ b/MdeModulePkg/MdeModulePkg.dec > @@ -540,6 +540,9 @@ > ## Include/Protocol/NonDiscoverableDevice.h > gEdkiiNonDiscoverableDeviceProtocolGuid = { 0x0d51905b, 0xb77e, 0x452a, > {0xa2, 0xc0, 0xec, 0xa0, 0xcc, 0x8d, 0x51, 0x4a } } > > + ## Include/Protocol/IoMmu.h > + gEdkiiIoMmuProtocolGuid = { 0x4e939de9, 0xd948, 0x4b0f, { 0x88, 0xed, > 0xe6, 0xe1, 0xce, 0x51, 0x7c, 0x1e } } > + > # > # [Error.gEfiMdeModulePkgTokenSpaceGuid] > # 0x80000001 | Invalid value provided. > -- > 2.7.4.windows.1 > > _______________________________________________ > edk2-devel mailing list > edk2-devel@lists.01.org > https://lists.01.org/mailman/listinfo/edk2-devel _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel
