zephyr/doc/hardware/arch/arc-support-status.rst

90 lines
8.1 KiB
ReStructuredText

Zephyr support status on ARC processors
#######################################
Overview
********
This page describes current state of Zephyr for ARC processors and some future
plans. Please note that
* plans are given without exact deadlines
* software features require corresponding hardware to be present and
configured the proper way
* not all the features can be enabled at the same time
Support status
**************
Legend:
**Y** - yes, supported; **N** - no, not supported; **WIP** - Work In Progress;
**TBD** - to be decided
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| | **Processor families** |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| | **EM** | **HS3x/4x** | **EV** | **HS5x** | **HS6x** |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| Port status | upstreamed | upstreamed | WIP | upstreamed | upstreamed |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| **Features** |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| Closely coupled memories (ICCM, DCCM) [#f1]_ | Y | Y | TBD | TBD | TBD |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| Execution with caches - Instruction/Data, L1/L2 caches | Y | Y | Y | Y | Y |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| Hardware-assisted unaligned memory access | Y [#f2]_ | Y | TBD | Y | Y |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| Regular interrupts with multiple priority levels, direct interrupts | Y | Y | TBD | Y | Y |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| Fast interrupts, separate register banks for fast interrupts | Y | Y | TBD | N | N |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| Hardware floating point unit (FPU) | Y | Y | N | TBD | TBD |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| Symmetric multiprocessing (SMP) support, switch-based | N/A | Y | TBD | Y | Y |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| Hardware-assisted stack checking | Y | Y | TBD | N | N |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| Hardware-assisted atomic operations | N/A | Y | TBD | Y | Y |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| DSP ISA | Y | N [#f3]_ | TBD | TBD | TBD |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| DSP AGU/XY extensions | WIP [#f3]_ | N [#f3]_ | TBD | TBD | TBD |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| Userspace | Y | Y | N | TBD | TBD |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| Memory protection unit (MPU) | Y | Y | TBD | N | N |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| Memory management unit (MMU) | N/A | N | N/A | N | N |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| SecureShield | Y | N/A | N/A | N/A | N/A |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| Single-thread kernel support [#f5]_ | Y | Y | TBD | Y | Y |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| **Toolchains** |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| GNU (open source GCC-based) | Y | Y | N | Y | Y |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| MetaWare (proprietary Clang-based) | Y | Y | Y | Y | Y |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| **Simulators** |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| QEMU (open source) [#f4]_ | Y | Y | N | Y | Y |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
| nSIM (proprietary, provided by MetaWare Development Tools) | Y | Y | Y | Y | Y |
+---------------------------------------------------------------------+------------+-------------+--------+------------+------------+
Notes
*****
.. [#f1] usage of CCMs is limited on SMP systems
.. [#f2] except the systems with secure features (SecureShield) due to HW
limitation
.. [#f3] We only support save/restore ACCL/ACCH registers in task's context.
Rest of DSP/AGU registers save/restore isn't implemented but kernel
itself does not use these registers. This allows single task per
core to use DSP/AGU safely.
.. [#f4] QEMU doesn't support all the ARC processor's HW features. For the
detailed info please check the ARC QEMU documentation
.. [#f5] Single-thread kernel is support only for single core targets