Use the encoding recommended by the PSCI specification: four bits for
the power state at each power level.
SCPI provides no way to handshake an exit from a standby state, so the
only possible standby state is the architectural WFI state. Since WFI
can be used outside of PSCI, we do not allow passing in standby states.
Change-Id: I4b3b84e5c255ee58a25255a0cab5d7623425086e
Signed-off-by: Samuel Holland <samuel@sholland.org>
Aligning the PSCI and SCPI power states avoids some code to translate
between the two. This also makes room for an intermediate power state,
for future firmware capability growth.
Change-Id: I26691085f277a96bd405e3305ab0fe390a92b418
Signed-off-by: Samuel Holland <samuel@sholland.org>
The SRAM on Allwinner platforms is shared between BL31 and coprocessor
firmware. Previously, SRAM was mapped as normal memory by default.
This scheme requires carveouts and cache maintenance code for proper
synchronization with the coprocessor.
A better scheme is to only map pages owned by BL31 as normal memory,
and leave everything else as device memory. This removes the need for
cache maintenance, and it makes the mapping for BL31 RW data explicit
instead of magic.
Signed-off-by: Samuel Holland <samuel@sholland.org>
Change-Id: I820ddeba2dfa2396361c2322308c0db51b55c348
In order to keep SCP firmware as optional, the original, limited native
PSCI implementation was kept around as a fallback. This turned out to be
a good decision, as some newer SoCs omit the ARISC, and thus cannot run
SCP firmware.
However, keeping the two implementations in one file makes things
unnecessarily messy. First, it is difficult to compile out the
SCPI-based implementation where it is not applicable. Second the check
is done in each callback, while scpi_available is only updated at boot.
This makes the individual callbacks unnecessarily complicated.
It is cleaner to provide two entirely separate implementations in two
separate files. The native implementation does not support any kind of
CPU suspend, so its callbacks are greatly simplified. One function,
sunxi_validate_ns_entrypoint, is shared between the two implementations.
Finally, the logic for choosing between implementations is kept in a
third file, to provide for platforms where only one implementation is
applicable and the other is compiled out.
Change-Id: I4914f07d8e693dbce218e0e2394bef15c42945f8
Signed-off-by: Samuel Holland <samuel@sholland.org>
Samuel Holland