Introduce INTRNG support for MIPS

[Sgalabov_gmail.com]

Summary

This introduces INTRNG support for the MIPS platforms. It is taken from ARM and the work has been done by Alexander Kabaev as part of his CI20 port.

I have tried to extract the INTRNG-related changes only and am also relying on this as part of the Ralink/Mediatek support.

To follow:

1. proper MIPS timer attachment when using INTRNG
2. suggestion to remove bus_space_fdt on MIPS and have bus_space_generic do the right things when mapping/unmapping bus space.

[skra]

sys/mips/include/intr.h

95 ↗

(On Diff #12991)

IMO, almost all things here should be in some common header in sys/sys. I wonder why such header was not created when INTRNG was moved in sys/kern.

[kan]

I do not see mips_pic.c in this patch, which is supposed to the the generic MIPS32 intr controller and is the place where cpu_establish_hard_intr for INTRNG is implemented. If you do not need rest of the mips_pic.c, consider moving these into an independent implementation file (mips/mips/intr.c?). You will need to export the root PIC pointer from MI intr code for that and that is the reason why I kept function in the file that implements root PIC on my SOC.

sys/mips/include/intr.h

95 ↗

(On Diff #12991)

Because unifying .h files as declared as TODO by adrian and he is still on the hook to do it some day, I hope.

sys/mips/mips/nexus.c

424 ↗

(On Diff #12991)

This bit is unrelated to INTRNG really, is it not? We should be able to avoid dragging it into -current only to be replaced later by fdtbus_bs_tag removal patch.

454 ↗

(On Diff #12991)

Same here.

605 ↗

(On Diff #12991)

This bit is also not an INTRNG piece, but rather a separate change than has an implication of enabling bus passes on the whole MIPS platform and as such probably deserves a separate commit.

[kan]

sys/mips/include/intr.h

47 ↗

(On Diff #12991)

This comment is not true, there is no dependency on exception.S anymore as corresponding block was #ifdef-ed out in exception.S in favor of code implemented by common intr.c.

[Sgalabov_gmail.com]

I've updated the patch, addressing kan's comments. I'll send out a separate review for enabling bus pass on MIPS (together with enabling it for the mips_pic (intr.c) tomorrow. I'll also update the bus_space_fdt removal patch tomorrow.

[kan]

I wasn't quite clear, my apologies. I still want to have mips_pic.c, not intr.c in the source. I only wanted intr.c IFF you were to decide to move cpu_establish_hard_intr and friends into a separate file and make them with arbitrary root PICm only then I called for the intr.c file. In other words, rename your intr.c to mips_pic.c for now.

[Sgalabov_gmail.com]

Renamed sys/mips/mips/intr.c to sys/mips/mips/mips_pic.c per Alexander Kabaev's request (sorry, I must have misunderstood what you meant originally).

[adrian]

ok, so how about we (read: me) split out the arm intrng definitions into sys/sys/ and then you can update your patch.

I just was worried that we'd need "more" and/or "different" fields between arm intrng and mips intrng.

Let me go do that soon. Thanks!

sys/mips/include/intr.h

96 ↗

(On Diff #13018)

Yeah, I was waiting for some people to use it in the MIPS world before I decided to unify this stuff. If you think this is all generic enough to use in your MIPS_INTRNG world then let's do that as a first pass. Then we can commit this stuff, minus all of the duplicate code.

How's that sound?

[Sgalabov_gmail.com]

Patch updated to use sys/sys/intr.h for the common parts between ARM and MIPS.
Also, FDT-related headers are now conditionally included in order to allow MIPS systems that do not support FDT to move to INTRNG should they wish to.

[mizhka]

head/sys/mips/mips/mips_pic.c

219–222

Hi,

The variable "tf" seems to be undefined, and I suppose it's "struct trapframe*"? Does MIPS_INTRNG support "device hwpmc"?

Thanks!