Krait (processor) explained

Krait
Produced-Start:	2012
Slowest:	1
Fastest:	2.7
Slow-Unit:	GHz
Fast-Unit:	GHz
Designfirm:	Qualcomm
Manuf1:	Qualcomm
Arch:	ARMv7-A, Thumb-2
Numcores:	2 or 4
L1cache:	16KiB and 16KiB
L2cache:	1MiB or 2MiB
Predecessor:	Scorpion
Successor:	Kryo

Qualcomm Krait is an ARM-based central processing unit included in the Snapdragon S4 and earlier models of Snapdragon 400/600/800 series SoCs. It was introduced in 2012 as a successor to the Scorpion CPU and although it has architectural similarities, Krait is not a Cortex-A15 core, but it was designed in-house.^[1] In 2015, Krait was superseded by the 64-bit Kryo architecture, first introduced in Snapdragon 820 SoC.

Overview

• 11 stage integer pipeline with 3-way decode and 4-way out-of-order speculative issue superscalar execution
• Pipelined VFPv4^[2] and 128-bit wide NEON (SIMD)
• 7 execution ports
• 4 KB + 4 KB direct mapped L0 cache
• 16 KB + 16 KB 4-way set associative L1 cache
• 1 MB (dual-core) or 2 MB (quad-core) 8-way set-associative L2 cache
• Dual or quad-core configurations
• Performance (DMIPS/MHz):
  • Krait 200: 3.3 (28 nm LP)
  • Krait 300: 3.39^[3] (28 nm LP)
  • Krait 400: 3.39 (28 nm HPm)
  • Krait 450: 3.51 (28 nm HPm)

See also

• Scorpion (CPU)
• Kryo (microarchitecture)
• Comparison of ARMv7-A cores
• List of Qualcomm Snapdragon processors

External links

• Qualcomm's Snapdragon S4 Site.

Notes and References

1. Web site: Qualcomm's New Snapdragon S4: MSM8960 & Krait Architecture Explored . . October 7, 2011 . Brian Klug . Anand Lal Shimpi . 2013-07-28.
2. Web site: Qualcomm Snapdragon S4 (Krait) Performance Preview - 1.5 GHz MSM8960 MDP and Adreno 225 Benchmarks . . February 21, 2012 . Brian Klug . Anand Lal Shimpi . 2013-07-28.
3. Web site: Krait 300 Bumps Up Performance . Linley on Mobile . The Linley Group . December 18, 2012 . Linley Gwennap . 2013-07-28.