528bef2d22
It's not uncommon to have Zephyr running in environments where it shares a memory bus with a foreign/non-Zephyr system (both the older Intel Quark and cAVS audio DSP systems share this property). In those circumstances, it would be nice to have a utility that allows an arbitrary-sized chunk of that memory to be used as a unidirectional buffered byte stream without requiring complicated driver support. sys_winstream is one such abstraction. This code is lockless, it makes no synchronization demands of the OS or hardware beyond memory ordering[1]. It implements a simple file/socket-style read/write API. It produces small code and is high performance (e.g. a read or write on Xtensa is about 60 cycles plus one per byte copied). It's bidirectional, with no internal Zephyr dependencies (allowing it to be easily ported to the foreign system). And it's quite a bit simpler (especially for the reader) than the older cAVS trace protocol it's designed to replace. [1] Which means that right now it won't work reliably on arm64 until we add a memory barrier framework to Zephyr! See notes in the code; the locations for the barriers are present, but there's no utility to call. Signed-off-by: Andy Ross <andrew.j.ross@intel.com> |
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| .. | ||
| gui | ||
| libc | ||
| open-amp | ||
| os | ||
| posix | ||
| smf | ||
| util | ||
| CMakeLists.txt | ||
| Kconfig | ||