This probably wants a cleanup, but I'm holding off until I know for sure
how the rest of the things that need doing fit together.
Tested on NVS300 by hacking up perflvl 1 to require PLL mode, and switching
between perflvl 3 and 1.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
The binary driver appears to do various bits and pieces of the memory
clock frequency change at different times, depending on the particular
transition that's occuring. I've attempted to replicate this here
for div->pll, pll->div and div->div transitions.
With some additional (patches upcoming) magic regs being bashed, this
allows me to correctly transition between all 3 perflvls on NVS300.
pll->pll transitions will *not* work correctly at the moment, pending
me tricking the binary driver into doing one and seeing how to correctly
handle it.
This patch also handles (hopefully) 0x1110e0, which appears to need
changing depending on whether in PLL or divider mode.. Maybe. We'll
see.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
The reg calculation may get moved elsewhere at some point, but lets
figure out what exactly we need to do first.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Reporting an error is better than silently refusing to reclock.
V2: Use the same logic on nv40
Signed-off-by: Martin Peres <martin.peres@labri.fr>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
The core/mem/shader clocks don't support the fractional feedback divider,
causing our calculated clocks to be off by quite a lot in some cases. To
solve this we will switch to a search-based algorithm when fN is NULL.
For my NVA8 at PL3, this actually generates identical cooefficients to
the binary driver. Hopefully that's a good sign, and that does not
break VPLL calculation for someone..
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Definitely not 100% correct, but, for the configurations I've seen used
it'll read back the correct clocks now.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>