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Convert plain text documentation to reStructuredText format and add it to Sphinx TOC tree. No essential content change. This also merges README.N1213 contents into the new nds32.rst file. Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
101 lines
3.2 KiB
ReStructuredText
101 lines
3.2 KiB
ReStructuredText
.. SPDX-License-Identifier: GPL-2.0+
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NDS32
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=====
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NDS32 is a new high-performance 32-bit RISC microprocessor core.
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http://www.andestech.com/
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AndeStar ISA
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------------
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AndeStar is a patent-pending 16-bit/32-bit mixed-length instruction set to
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achieve optimal system performance, code density, and power efficiency.
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It contains the following features:
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- Intermixable 32-bit and 16-bit instruction sets without the need for
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mode switch.
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- 16-bit instructions as a frequently used subset of 32-bit instructions.
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- RISC-style register-based instruction set.
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- 32 32-bit General Purpose Registers (GPR).
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- Upto 1024 User Special Registers (USR) for existing and extension
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instructions.
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- Rich load/store instructions for...
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- Single memory access with base address update.
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- Multiple aligned and unaligned memory accesses for memory copy and stack
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operations.
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- Data prefetch to improve data cache performance.
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- Non-bus locking synchronization instructions.
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- PC relative jump and PC read instructions for efficient position independent
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code.
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- Multiply-add and multiple-sub with 64-bit accumulator.
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- Instruction for efficient power management.
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- Bi-endian support.
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- Three instruction extension space for application acceleration:
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- Performance extension.
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- Andes future extensions (for floating-point, multimedia, etc.)
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- Customer extensions.
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AndesCore CPU
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-------------
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Andes Technology has 4 families of CPU cores: N12, N10, N9, N8.
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For details about N12 CPU family, please check below N1213 features.
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N1213 is a configurable hard/soft core of NDS32's N12 CPU family.
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N1213 Features
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^^^^^^^^^^^^^^
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CPU Core
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- 16-/32-bit mixable instruction format.
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- 32 general-purpose 32-bit registers.
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- 8-stage pipeline.
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- Dynamic branch prediction.
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- 32/64/128/256 BTB.
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- Return address stack (RAS).
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- Vector interrupts for internal/external.
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interrupt controller with 6 hardware interrupt signals.
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- 3 HW-level nested interruptions.
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- User and super-user mode support.
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- Memory-mapped I/O.
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- Address space up to 4GB.
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Memory Management Unit
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- TLB
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- 4/8-entry fully associative iTLB/dTLB.
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- 32/64/128-entry 4-way set-associati.ve main TLB.
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- TLB locking support
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- Optional hardware page table walker.
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- Two groups of page size support.
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- 4KB & 1MB.
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- 8KB & 1MB.
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Memory Subsystem
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- I & D cache.
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- Virtually indexed and physically tagged.
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- Cache size: 8KB/16KB/32KB/64KB.
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- Cache line size: 16B/32B.
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- Set associativity: 2-way, 4-way or direct-mapped.
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- Cache locking support.
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- I & D local memory (LM).
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- Size: 4KB to 1MB.
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- Bank numbers: 1 or 2.
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- Optional 1D/2D DMA engine.
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- Internal or external to CPU core.
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Bus Interface
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- Synchronous/Asynchronous AHB bus: 0, 1 or 2 ports.
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- Synchronous High speed memory port.
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(HSMP): 0, 1 or 2 ports.
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Debug
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- JTAG debug interface.
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- Embedded debug module (EDM).
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- Optional embedded program tracer interface.
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Miscellaneous
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- Programmable data endian control.
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- Performance monitoring mechanism.
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The NDS32 ports of u-boot, the Linux kernel, the GNU toolchain and other
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associated software are actively supported by Andes Technology Corporation.
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