ARM11
ARM11 is a group of 32-bit reduced [instruction set computer|RISC] ARM processor cores licensed by ARM Holdings. The ARM11 core family consists of ARM1136J-S, ARM1156T2-S, ARM1176JZ-S, and ARM11MPCore. Since ARM11 cores were released from 2002 to 2005, and no longer recommended for new IC designs, newer alternatives are ARM Cortex-A and ARM Cortex-R cores.
Overview
The ARM11 product family introduced the ARMv6 architectural additions which had been announced in October 2001. These include SIMD media instructions, multiprocessor support, exclusive loads and stores instructions and a new cache architecture. The implementation included a significantly improved instruction processing pipeline, compared to previous ARM9 or ARM10 families, and is used in smartphones from Apple, Nokia, and others. The initial ARM11 core was released to licensees in October 2002.The ARM11 family are currently the only ARMv6-architecture cores. There are, however, ARMv6-M cores, addressing microcontroller applications; ARM11 cores target more demanding applications.
Differences from ARM9
In terms of instruction set, ARM11 builds on the preceding ARM9 generation. It incorporates all ARM926EJ-S features and adds the ARMv6 instructions for media support and accelerating IRQ response.Microarchitecture improvements in ARM11 cores include:
- SIMD instructions which can double MPEG-4 and audio digital signal processing algorithm speed
- Cache is physically addressed, solving many cache aliasing problems and reducing context switch overhead.
- Unaligned and mixed-endian data access is supported.
- Reduced heat production and lower overheating risk
- Redesigned pipeline, supporting faster clock speeds
- * Longer: 8 stages
- * Out-of-order completion for some operations
- * Dynamic branch prediction/folding
- * Cache misses don't block execution of non-dependent instructions.
- * Load/store parallelism
- * ALU parallelism
- 64-bit data paths
ARM makes an effort to promote recommended Verilog coding styles and techniques. This ensures semantically rigorous designs, preserving identical semantics throughout the chip design flow, which included extensive use of formal verification techniques. Without such attention, integrating an ARM11 with third-party designs could risk exposing hard-to-find latent bugs. Due to ARM cores being integrated into many different designs, using a variety of logic synthesis tools and chip manufacturing processes, the impact of its register-transfer level quality is magnified many times. The ARM11 generation focused more on synthesis than previous generations, making such concerns more of an issue.
Cores
There are four ARM11 cores:- ARM1136
- ARM1156, introduced Thumb2 instructions
- ARM1176, introduced security extensions
- ARM11MPcore, introduced multicore support
Chips
- Ambarella A5s, A7, A7L
- ASPEED Technology Inc. AST25xx
- Broadcom BCM2835, BCM21553
- Cavium ECONA CNS3000 series
- CSR Quatro 4230, 45xx, 53xx
- Freescale Semiconductor i.MX3x series, such as i.MX31, i.MX35
- Infotmic IMAPX2xx
- Nintendo CTR-CPU
- NTC Module 1879VYa1Ya, K1879KhB1Ya, 1879KhK1Ya, K1888VS018
- Nvidia Tegra
- MediaTek MT6276, MT6573
- Mindspeed Comcerto 1000
- Philips Semiconductor/NXP/ST-NXP Wireless Nomadik STn8820
- PLX Technology NAS782x
- Qualcomm MSM720x, MSM7x27
- Qualcomm Atheros AR7400
- Samsung S3C64xx, S5P64xx, S5L87xx, S5L89xx or Exynos Dual with Logic11
- Telechips TCC8902
- Texas Instruments OMAP2 series, with a TMS320 C55x or C64x DSP as a second core
- iPhone 3G series, with a Samsung ARM 1176JZ chip
- Xcometic KVM2800