4 INTRODUCTION
Universal Flash Storage (UFS) is a simple, high performance, mass storage device with a serial interface. It is primarily for use in mobile systems, between host processing and mass storage memory devices. The following is the summary of the UFS features.
4.1 General Features
- Target performance
- High speed GEARs (1)
- Support for GEAR1 is mandatory
- Support for GEAR2 is mandatory
- Support for GEAR3 is optional
- High speed GEARs (1)
- Target host applications
- Mobile phone, UMPC, DSC, PMP, MP3 and any other applications that require mass storage, bootable mass storage, and external card
- Target device types
- External card
- Micro size for mobile and portable devices
- Full size or adaptor for DSC and large devices
- Embedded packages
- Mass storage and bootable mass storage
- Future expansion of device class types
- I/O devices, camera, wireless, … , etc.
- External card
- Topology
- One device per UFS port. A topology to support multiple devices on a single interface is planned for future revision
- UFS Layering
- UFS Command Set Layer (UCS)
- Simplified SCSI command set based on SBC and SPC. UFS will not modify these SBC and SPC Compliant commands. Option for defining UFS Native command and future extension exist.
- UFS Transport Protocol Layer (UTP)
- JEDEC to define the supported protocol layer, i.e., UTP for SCSI. This does not exclude the support of other protocol in UFS Transport Protocol Layer.
- UFS Interconnect Layer (UIC)
- MIPI UniProSM [MIPI-UniPro] is adopted for data link layer
- MIPI M-PHY SM [MIPI-M-PHY ] is adopted for physical layer
- UFS Command Set Layer (UCS)
NOTE 1 See 6.5.1 for details.