Messages in this thread | | | Date | Wed, 27 Aug 2014 13:35:46 -0500 | Subject | Re: [PATCH 4/7] ARM: OMAP2+: powerdomain: introduce logic for finding valid power domain | From | Nishanth Menon <> |
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On Wed, Aug 27, 2014 at 1:27 PM, Kevin Hilman <khilman@deeprootsystems.com> wrote: > Nishanth Menon <nm@ti.com> writes: > >> powerdomain configuration in OMAP is done using PWRSTCTRL register for >> each power domain. However, PRCM lets us write any value we'd like to >> the logic and power domain target states, however the SoC integration >> tends to actually function only at a few discrete states. These valid >> states are already in our powerdomains_xxx_data.c file. >> >> So, provide a function to easily query valid low power state that the >> power domain is allowed to go to. >> >> Based on work originally done by Jean Pihet <j-pihet@ti.com> >> https://patchwork.kernel.org/patch/1325091/ . There is no attempt to >> create a new powerdomain solution here, except fixing issues seen >> attempting invalid programming attempts. Future consolidation to the >> generic powerdomain framework should consider this requirement as >> well. >> >> Similar solutions have been done in product kernels in the past such >> as: >> https://android.googlesource.com/kernel/omap.git/+blame/android-omap-panda-3.0/arch/arm/mach-omap2/pm44xx.c >> >> Signed-off-by: Nishanth Menon <nm@ti.com> >> --- > > nit: this is part of a fixes series, but it's more of a new feature. > > That being said, the feature is needed and looks OK, except for... > >> +up_search: >> + /* OK, no deeper ones, can we get a higher match? */ >> + new_pwrst = req_state + 1; >> + while (!(pwrdm_states & BIT(new_pwrst))) { >> + /* BUG if we have messed up database */ >> + BUG_ON(new_pwrst > PWRDM_POWER_ON); > > I don't think this is BUG() worthy, and should have a saner way to recover.
it is not even a legal value to have a power state higher than ON. I mean, yeah, we can do if (new_pwrst > PWRDM_POWER_ON) { pr_debug("powerdomain: %s: fix my powerdomain max to ON\n", pwrdm->name); return PWRDM_POWER_ON; }
if that is your suggestion here, personally, I would use a WARN at least here..
-- --- Regards, Nishanth Menon
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