AMD_IOMMU_CMD_OPCODE
AMD_IOMMU_REG_SET32(&cmdptr[1], AMD_IOMMU_CMD_OPCODE, 0x03);
AMD_IOMMU_REG_SET32(&cmdptr[1], AMD_IOMMU_CMD_OPCODE, 0x04);
AMD_IOMMU_REG_SET32(&cmdptr[1], AMD_IOMMU_CMD_OPCODE, 0x05);
AMD_IOMMU_REG_SET32(&cmdptr[1], AMD_IOMMU_CMD_OPCODE, 0x01);
AMD_IOMMU_REG_SET32(&cmdptr[1], AMD_IOMMU_CMD_OPCODE, 0x02);