RE: [PATCH] arm64: dts: realtek: Add Realtek rtd1619 and mjolnir

From: James Tai
Date: Fri Nov 08 2019 - 10:36:31 EST


Hi Andreas,

Thank you for your review.

[...]
> Just to be sure: This is one cluster of 6 CPUs? Or is it some 4+2 big.LITTLE,
> DynamiQ or whatever multi-cluster configuration with different frequencies,
> power domains or something?
>
Yes, it is one cluster of 6 CPUs.

[...]
> > +
> > + l2: l2-cache {
> > + compatible = "cache";
> > + next-level-cache = <&l3>;
> > +
> > + };
> > +
> > + l3: l3-cache {
> > + compatible = "cache";
> > + };
>
> Caches look weird - only cpu0 uses L2 and all others use L3 directly?
>
Yes, only cpu0 uses L2 and others use L3 directly.

[...]
> Generic question also applying to my RTD1295/RTD1195 patches: Are you sure
> about GIC_CPU_MASK_RAW(0xf) or could this be GIC_CPU_MASK_SIMPLE(6)
> in this case? This here would seem equivalent of GIC_CPU_MASK_SIMPLE(8).
>
The GICv3 does not have affinity bitmap in the binding for PPI
interrupts. So remove the GIC_CPU_MASK_RAW() macro.

[...]
>
> And double-check whether you actually need <2> - compare rtd129x.dtsi using
> <1> because nothing went beyond 32-bit address space. It was a review
> request back then. Can RTD1619 have more than 2 GiB RAM, with a second
> RAM region in high mem, requiring two cells for memory nodes?
>
The RTD1619 can support more than 2 GiB RAM.

[...]
>
> Is the UART no longer behind an IRQ mux on RTD1619, or is the above the IRQ
> mux interrupt as a workaround for lack of in-tree irqchip driver?
>
Yes, the UART no longer behind an IRQ mux on RTD1619.

[...]
> Are you sure you don't have GICC, GICH, GICV and IRQ? No MBI support?
>
The RTD1619 don't have GICC, GICH, GICV and no support MBI.

> For RTD1295 I extended the GICv2 node during review, and KVM initialized
> fine, although I'm not sure whether I've run an actual guest yet, given how
> many drivers were missing still.
>
> (I'd also appreciate Realtek to review my RTD1195 patch's GIC [1] for whether
> we should have all four regions and some interrupt there - the OEM's U-Boot
> doesn't boot in HYP mode, so I can't test myself.)
>
I will help with review.

[...]

Regards,
James