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The ARM1176JZ-S processor provides support for extensions to ARMv6 that include:
Store and Load Exclusive instructions for bytes, halfwords and doublewords and a new Clear Exclusive instruction.
A true no-operation instruction and yield instruction.
Architectural remap registers.
Cache size restriction through CP15 c1. You can restrict cache size to 16KB for Operating Systems (OSs) that do not support page coloring.
Revised use of TEX remap bits. The ARMv6 MMU page table descriptors use a large number of bits to describe all of the options for inner and outer cachability. In reality, it is believed that no application requires all of these options simultaneously. Therefore, it is possible to configure the ARM1176JZ-S processor to support only a small number of options by means of the TEX remap mechanism. This implies a level of indirection in the page table mappings.
The TEX CB encoding table provides two OS managed page table bits. For binary compatibility with existing ARMv6 ports of OSs, this gives a separate mode of operation of the MMU. This is called the TEX remap configuration and is controlled by bit [28] TR in CP15 Register 1.
Revised use of AP bits. In the ARM1176JZ-S processor the APX and AP[1:0] encoding b111 is Privileged or User mode read only access. AP[0] indicates an abort type, Access Bit fault, when CP15 c1[29] is 1.