Next Mobile Storage Solution - Evolution from eMMC to UFS -

Mobile Memory Forum CES 2012

Hangu Sohn

Samsung Electronics Co. LTD

Unit : M Set

Smartphones overtake PCs in 2011

Source: Samsung Marketing, 3Q11

2X

● We’re going ‘Mobile!’

• From ‘11, Smart-phones overtake PC Shipments and Tablets will add to the gap significantly

● What is Driving High Performance in Mobile…

• High Computing Power(DC/QC* CPU) & High Storage Capacity (>64GB)

• Low Latency and High IOPS (Random) & Bandwidth (Sequential)

Video editing/ 3D Games

Fluid Responsiveness

Seamless Web Surfing/Social Networking

DC/QC: Dual Core, Quad Core

● What is UFS (Universal Flash Storage)?

• Low Power of eMMC + High Performance of SCSI SSD

• Two form factors: 1) Embedded SSD 2) SD card form factor

SCSI

SSD

e-MMC

UFS

● UFS: Less pins by/in Serial and Multiple Lanes

• Two types of speed modes and a ‘Minute Power’ state for low power

eMMC: Limitation of Parallel Interface

Parallel data pins

Pe

rfo

rman

ce

•More parallels higher power

•More pins Cost Up

•Signal Skewing •Crosstalk

Optional expansion

UFS: MIPI M-PHY for higher speed

M-TX

M-RX

M-TX

M-RX

M-RX

M-TX

M-RX

M-TX

UFS: Two types of Speed modes and Multiple Gears UFS: Power State Diagram

● UFS: Utilizes and extends eMMC functionality

UFS e-MMC 4.5

Security Trim/Discard Yes

Sanitize Yes

RPMB Yes

Data Integrity Write Protect Yes

Partitioning Yes

Performance

enhancement

Cached opt Yes

Data-Tag Yes

Context-ID Yes

Packed CMD CMD queuing

Flash

Management

Background opt Yes

Real time Clock Yes

Partition types Yes

Protocol

enhancement

Synch Asynch

State transition Stateless

● UFS: Optimized for Multi-threaded Applications • Full utilization of multiple NAND operations

- UFS: Heterogeneous commands can be executed in parallel vs. SATA: Parallel execution, but limited by SATA protocol

<Key Assumptions: Write takes 3x longer than read. Write-through mode. No storage cache available>

Time

Thread A

Thread B

Thread D

Thread C

Wo

rk L

oa

d

Time

UFS

SATA

W

W

R R R R

W

R

R R

#1

#2

#3

#4

NAND

R W

W

W

R

R

W

W

R R R R R

R R R

W

W

W #1

#2

#3

#4

NAND

W

W

R

R R R R R

R R

R

R

R

R

R

Tx

Rx

Tx

Rx

R

Host I/F

Host I/F

Waiting for completion of write

Long idle (Write delayed)

Simultaneous Tx/Rx possible

Barrier

Normalized Throughput UFS vs .SSD

QuadRant_IO x1.79

RL_Bench x1.94

Web Browsing

x2.49

● UFS: Time-critical Applications • Worst UX: Request delay due to Storage Write Busy • Better User Experience: High Priority LU for time-critical application

Time

Suspended Suspended Suspended

UFS

SATA

Partition 0 (High Priority LU)

Partition 1

Single Partition

App Download App Install

App Download

App Download

App Install

Video Playing

Video Playing

App Install

Delayed Start Delayed Completion Failed to meet deadline

Camera Shooting Events Video Playing

Camera Shooting

Camera Shooting

Video Playing

Video Playing

App Install

Code execution

Code execution

Code execution

eMMC4.5 (HPI)

Long write

Media data read request

Media data read Pending over 100ms

Write Issue Write Completion

● UFS: High Bandwidth & High IOPS

• Sequential Performance: Separate R/W channel + Scalability by/through Multiple Lanes (x1/x2/x4) and Gears (3.0Gbps, 6.0Gbps)

• Random Performance: Asynchronous Protocol (Command Queuing)

2010 2011 2012 2013 2014

eMMC

SATA

2015

SD

HSIC (USB2)

Th

rou

gh

put M

bit/s

ec

Dual Lane

Single Lane

2010 2011 2012 2013 2014

SD

eMMC

SATA

2015 HSIC (USB2)

Read IO

PS

UFSA Estimates

UFSA : UFS Assoiaction

Sequential Performance

Random Performance

M-PHY : Mobile PHY has been defined by MIPI (Mobile Industry Processor Interface)

Re

lative

Id

le P

ow

er

● UFS: Optimizes Power to target Mobile applications

• UFS provides Lower Standby Power by adopting M-PHY

• Key point for ‘Always-On’

UFSA Estimates

SD eMMC UFS HSIC SATA

SATA Slumber

SATA DEVSLP

2011 2012

UFS 1.0 Editorial

MIPI M-PHY1.0

MIPI Unipro 1.4

HCI 1.0

Device

Chipset

● Industry moving to UFS…

• SPEC completed in ’11, not only for Devices but also HCI

• Coming up: Device & Host Chipset in ‘12

HCI: Host Controller Interface

Application

I/O Manager

File System

Storage Class Driver

UFS Device Driver

UFS HCI

Host Controller UFS Device

Compliant with e-MMC4.5 feature

Working on adoption

Compliant with SCSI & e-MMC

Compliant with SCSI

New Software driver

but Standard HCI &Device drivers S/W

H/W

● UFS provides easy Software adoption by e-MMC 4.5 features and SCSI compliance…

• UFS Device Driver & UFS HCI by Standard HCI & Device drivers

JC 64.5 UFSA ATC

Test procedure

& spec

UFS compliance

specification

Certification

● JEDEC has moved for setting up UFS Test Infra …

• JC64.5 for UFS test procedure & test spec

• Compliance/Certification will be available from UFSA soon

● UFS is Ready…Successfully demonstrated and converging with Portable Computing Devices

UFS Demo based on FPGA Level (by Samsung 4Q’11)

THANK YOU