user/sven/linux.git/drivers/opp, branch v5.12.8

opp: Don't drop extra references to OPPs accidentally

2021-03-12T03:56:52Z

We are required to call dev_pm_opp_put() from outside of the opp_table->lock as debugfs removal needs to happen lock-less to avoid circular dependency issues. commit cf1fac943c63 ("opp: Reduce the size of critical section in _opp_kref_release()") tried to fix that introducing a new routine _opp_get_next() which keeps returning OPPs that can be freed by the callers and this routine shall be called without holding the opp_table->lock. Though the commit overlooked the fact that the OPPs can be referenced by other users as well and this routine will end up dropping references which were taken by other users and hence freeing the OPPs prematurely. In effect, other users of the OPPs will end up having invalid pointers at hand. We didn't see any crash reports earlier as the exact situation never happened, though it is certainly possible. We need a way to mark which OPPs are no longer referenced by the OPP core, so we don't drop extra references to them accidentally. This commit adds another OPP flag, "removed", which is used to track this. And now we should never end up dropping extra references to the OPPs. Cc: v5.11+ # v5.11+ Fixes: cf1fac943c63 ("opp: Reduce the size of critical section in _opp_kref_release()") Signed-off-by: Beata Michalska [ Viresh: Almost rewrote entire patch, added new "removed" field, rewrote commit log and added the correct Fixes tag. ] Co-developed-by: Viresh Kumar Signed-off-by: Viresh Kumar

opp: Don't skip freq update for different frequency

2021-02-18T07:01:08Z

We skip the OPP update if the current and target OPPs are same. This is fine for the devices that don't support frequency but may cause issues for the ones that need to program frequency. An OPP entry doesn't really signify a single operating frequency but rather the highest frequency at which the other properties of the OPP entry apply. And we may reach here with different frequency values, while all of them would point to the same OPP entry in the OPP table. We just need to update the clock frequency in that case, though in order to not add special exit points we reuse the code flow from a normal path. While at it, rearrange the conditionals in the 'if' statement to check 'enabled' flag at the end. Fixes: 81c4d8a3c414 ("opp: Keep track of currently programmed OPP") Signed-off-by: Jonathan Marek [ Viresh: Improved commit log and subject, rename current_freq as current_rate, document it, remove local variable and rearrange code. ] Signed-off-by: Viresh Kumar

OPP: Add function to look up required OPP's for a given OPP

2021-02-04T11:00:14Z

Add a function that allows looking up required OPPs given a source OPP table, destination OPP table and the source OPP. Signed-off-by: Saravana Kannan Signed-off-by: Hsin-Yi Wang [ Viresh: Rearranged code, fixed return errors ] Signed-off-by: Viresh Kumar

opp: Don't ignore clk_get() errors other than -ENOENT

2021-02-02T05:00:53Z

Not all devices that need to use OPP core need to have clocks, a missing clock is fine in which case -ENOENT shall be returned by clk_get(). Anything else is an error and must be handled properly. Reported-by: Dmitry Osipenko Tested-by: Dmitry Osipenko Signed-off-by: Viresh Kumar

opp: Update bandwidth requirements based on scaling up/down

2021-02-02T05:00:53Z

The bandwidth must be scaled at a different point in the code flow based on if we are scaling up or down the frequency, otherwise this may cause undesired effects as the device will try to use more of the memory bandwidth which may be shared across several devices. Much like how regulators and required-opps are programmed. Reported-by: Dmitry Osipenko Reported-by: Akhil P Oommen Signed-off-by: Viresh Kumar Tested-by: Dmitry Osipenko

opp: Allow lazy-linking of required-opps

2021-02-02T05:00:53Z

The OPP core currently requires the required opp tables to be available before the dependent OPP table is added, as it needs to create links from the dependent OPP table to the required ones. This may not be convenient for all the platforms though, as this requires strict ordering for probing the drivers. This patch allows lazy-linking of the required-opps. The OPP tables for which the required-opp-tables aren't available at the time of their initialization, are added to a special list of OPP tables: lazy_opp_tables. Later on, whenever a new OPP table is registered with the OPP core, we check if it is required by an OPP table in the pending list; if yes, then we complete the linking then and there. An OPP table is marked unusable until the time all its required-opp tables are available. And if lazy-linking fails for an OPP table, the OPP core disables all of its OPPs to make sure no one can use them. Tested-by: Hsin-Yi Wang Signed-off-by: Viresh Kumar

opp: Remove dev_pm_opp_set_bw()

2021-02-02T05:00:53Z

All the users have migrated to dev_pm_opp_set_opp() now, get rid of the duplicate API, dev_pm_opp_set_bw(), which only performs a part of the new API. While at it, remove the unnecessary parameter to _set_opp_bw(). Signed-off-by: Viresh Kumar Tested-by: Dmitry Osipenko

opp: Implement dev_pm_opp_set_opp()

2021-02-02T04:58:07Z

The new helper dev_pm_opp_set_opp() can be used for configuring the devices for a particular OPP and can be used by different type of devices, even the ones which don't change frequency (like power domains). Signed-off-by: Viresh Kumar Tested-by: Dmitry Osipenko

opp: Update parameters of _set_opp_custom()

2021-02-02T04:58:03Z

Drop the unnecessary parameters and follow the pattern from _generic_set_opp_regulator(). While at it, also remove the local variable old_freq. Signed-off-by: Viresh Kumar Tested-by: Dmitry Osipenko

opp: Allow _generic_set_opp_clk_only() to work for non-freq devices

2021-02-02T04:58:01Z

In order to avoid conditional statements at the caller site, this patch updates _generic_set_opp_clk_only() to work for devices that don't change frequency (like power domains, etc.). Return 0 if the clk pointer passed to this routine is not valid. Signed-off-by: Viresh Kumar Tested-by: Dmitry Osipenko