PowerPC Page Tables Tutorial
#3
Thank you for the corrections, I appreciate it.

Regarding the integer vs float for zero-ing a table, if we were to ignore alignment, cache hits/misses, etc, integer stores and double-float stores have the same cycle latency (2:1). I remember a long time ago I was doing some quick tests on seeing how to zero a small block of memory quickly. IIIRC, dcbz came out on top even with it being an Execution Serialization instruction. Then again, I have an awful memory (lol)

I've found a few optimized memcpy PowerPC 32-bit implementations on the web and all of them implemented double-float stores to some degree to speed up the memcpy.

Regarding eieio, that shouldn't be needed if SGE is low in HID0. A sync shouldn't be required if this is being set in Real Mode (translation off) and if so, the sync would simply need to be done sometime after all the PTEs are written and before translation is enabled. I'll add them regardless for the case that SGE is high in HID0 and/or PTEs are being rewritten while translation is on.
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PowerPC Page Tables Tutorial - by Vega - 12-01-2022, 08:47 PM
RE: PowerPC Page Tables Tutorial - by Gaberboo - 12-17-2022, 11:07 PM
RE: PowerPC Page Tables Tutorial - by Vega - 12-18-2022, 12:16 AM

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