PiStorm Chat

[stephen_usher]

That's getting pretty quick.

[exxos]

* Have you noticed how most of exxos' smilies are about frustration and beating people up? This is the best I could come up with for gobsmacked and blown away

[mrbombermillzy]

@dad664npc That is some seriously cool work there.

* Have you noticed how most of exxos' smilies are about frustration and beating people up? This is the best I could come up with for gobsmacked and blown away

What Exxos means to say, is that you must have a sore head (like you've been hit repeatedly with a deck chair) after all that hard work.

[alexh]

Amazing work. I hope that it becomes stable enough to be a usable accelerator. (If it is already, hats off)

whilst stepping through the [emulator] code I realised that a lot of optimisations could be made. So implementing these changes to the non-baremetal code, performance has increased A LOT!

Are these optimisations being pushed upstream? I'm sure they would be very well received.

[dad664npc]

I think it's fairly stable. I can run all CPU variants with differing ROMs. Run various benchmarks on each. I can run Mint on 68030 and 68040.
The next stage is to get a few more users and test a bit more. Then we need to look at a bespoke hardware solution for the Atari.

Even a PI4 clocked at 1.5 GHz now offers good performance - CoreMark 36.18, Elite FB 2980
And if you crank it right up to 2.3 GHz - CoreMark 57.04, Elite FB 3391

GitHub is up to date - https://github.com/gotaproblem/pistorm-atari

And I have made a little more progress on the bare-metal version. I can now boot in to GEM - but it is painfully slow. Need to figure out the cache and MMU settings - so if anyone knows about that stuff...

[Badwolf]

I think it's fairly stable. I can run all CPU variants with differing ROMs. Run various benchmarks on each. I can run Mint on 68030 and 68040.
The next stage is to get a few more users and test a bit more. Then we need to look at a bespoke hardware solution for the Atari.

Fantastic work!

And I have made a little more progress on the bare-metal version. I can now boot in to GEM - but it is painfully slow. Need to figure out the cache and MMU settings - so if anyone knows about that stuff...

Slow in what way? Do you mean the ARM cache and MMU? 68k has neither, obviously.

BW

[dad664npc]

Slow in what way? Do you mean the ARM cache and MMU? 68k has neither, obviously.

Slow as in it takes several minutes to draw anything on the screen. I have configured the clocks for CPU=1.5 GHz and GPU=750 MHz and have confirmed they are set.
Yes the ARM side of things. What I have for enabling data and instruction caches does not do anything. I read somewhere that the PI MMU has to be enabled before cache can work. But trying to find info on this for 32 bit bare-metal isn't easy. Might have to try aarch64 again.

[Badwolf]

Slow in what way? Do you mean the ARM cache and MMU? 68k has neither, obviously.

Slow as in it takes several minutes to draw anything on the screen. I have configured the clocks for CPU=1.5 GHz and GPU=750 MHz and have confirmed they are set.
Yes the ARM side of things. What I have for enabling data and instruction caches does not do anything. I read somewhere that the PI MMU has to be enabled before cache can work. But trying to find info on this for 32 bit bare-metal isn't easy. Might have to try aarch64 again.

Ah. I know more Welsh than I do ARM. Presuambly Emu68 has had to tackle the same? Can you crib anything from that?

https://github.com/michalsc/Emu68/tree/master/src/raspi

BW

[Steve]

Also Michal the dev of emu68 is very available & helpful on the Discord, speaking directly to him might be a good idea!

[dad664npc]

I do speak to Michal but do not find him helpful at all. Maybe I'm asking the wrong questions