Messages in this thread | | | From | Chen-Yu Tsai <> | Date | Tue, 19 May 2015 10:51:12 +0800 | Subject | Re: [linux-sunxi] [RFC 0/7] ARM: sun9i: SMP support with Multi-Cluster Power Management |
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On Sat, May 16, 2015 at 6:08 PM, Ian Campbell <ijc@hellion.org.uk> wrote: > On Thu, 2015-05-14 at 14:10 +0800, Chen-Yu Tsai wrote: >> This is my attempt to support SMP and CPU hot plugging on the Allwinner >> A80 SoC. The A80 is a big.Little processor with 2 clusters of 4x Cortex-A7 >> and 4x Cortex-A15 cores. > > I thought there was a preference these days to support this sort of > thing via support PSCI in the firmware, which allows for other things > such as non-secure-world etc.
Ideally, yes. However, U-boot only has minimal A80 support for now. Also, multi-cluster support is not as simple as what we had for the A20. The kernel already has common multi-cluster code. With it we can do full SMP/hotplug support. Kernel code is also easier to write and debug than PSCI, which ATM is all per-platform assembly.
Also, my A31 and A23 PSCI implementations still need some work.
ChenYu
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