linux/drivers/opp, branch v5.7

opp: Manage empty OPP tables with clk handle

2020-04-13T10:44:55Z

With OPP core now supporting DVFS for IO devices, we have instances of IO devices (same IP block) which require an OPP on some platforms/SoCs while just needing to scale the clock on some others. In order to avoid conditional code in every driver which supports such devices (to check for availability of OPPs and then deciding to do either dev_pm_opp_set_rate() or clk_set_rate()) add support to manage empty OPP tables with a clk handle. This makes dev_pm_opp_set_rate() equivalent of a clk_set_rate() for devices with just a clk and no OPPs specified, and makes dev_pm_opp_set_rate(0) bail out without throwing an error. Signed-off-by: Rajendra Nayak Signed-off-by: Viresh Kumar

Merge tag 'ioremap-5.6' of git://git.infradead.org/users/hch/ioremap

2020-01-27T21:03:00Z

Pull ioremap updates from Christoph Hellwig: "Remove the ioremap_nocache API (plus wrappers) that are always identical to ioremap" * tag 'ioremap-5.6' of git://git.infradead.org/users/hch/ioremap: remove ioremap_nocache and devm_ioremap_nocache MIPS: define ioremap_nocache to ioremap

remove ioremap_nocache and devm_ioremap_nocache

2020-01-06T08:45:59Z

ioremap has provided non-cached semantics by default since the Linux 2.6 days, so remove the additional ioremap_nocache interface. Signed-off-by: Christoph Hellwig Acked-by: Arnd Bergmann

opp: Replace list_kref with a local counter

2019-12-10T10:27:00Z

A kref or refcount isn't the right tool to be used here for counting number of devices that are sharing the static OPPs created for the OPP table. For example, we are reinitializing the kref again, after it reaches a value of 0 and frees the resources, if the static OPPs get added for the same OPP table structure (as the OPP table structure was never freed). That is messy and very unclear. This patch makes parsed_static_opps an unsigned integer and uses it to count the number of users of the static OPPs. The increment and decrement to parsed_static_opps is done under opp_table->lock now to make sure no races are possible if the OPP table is getting added and removed in parallel (which doesn't happen in practice, but can in theory). Signed-off-by: Viresh Kumar

opp: Free static OPPs on errors while adding them

2019-12-10T10:26:56Z

The static OPPs aren't getting freed properly, if errors occur while adding them. Fix that by calling _put_opp_list_kref() and putting their reference on failures. Fixes: 11e1a1648298 ("opp: Don't decrement uninitialized list_kref") Signed-off-by: Viresh Kumar

PM / OPP: Support adjusting OPP voltages at runtime

2019-11-11T04:57:15Z

On some SoCs the Adaptive Voltage Scaling (AVS) technique is employed to optimize the operating voltage of a device. At a given frequency, the hardware monitors dynamic factors and either makes a suggestion for how much to adjust a voltage for the current frequency, or it automatically adjusts the voltage without software intervention. Add an API to the OPP library for the former case, so that AVS type devices can update the voltages for an OPP when the hardware determines the voltage should change. The assumption is that drivers like CPUfreq or devfreq will register for the OPP notifiers and adjust the voltage according to suggestions that AVS makes. This patch is derived from [1] submitted by Stephen. [1] https://lore.kernel.org/patchwork/patch/599279/ Signed-off-by: Stephen Boyd [Roger Lu: Changed to rcu less implementation] Signed-off-by: Roger Lu [s.nawrocki@samsung.com: added handling of OPP min/max voltage] Signed-off-by: Sylwester Nawrocki Signed-off-by: Viresh Kumar

opp: Reinitialize the list_kref before adding the static OPPs again

2019-10-23T05:28:44Z

The list_kref reaches a count of 0 when all the static OPPs are removed, for example when dev_pm_opp_of_cpumask_remove_table() is called, though the actual OPP table may not get freed as it may still be referenced by other parts of the kernel, like from a call to dev_pm_opp_set_supported_hw(). And if we call dev_pm_opp_of_cpumask_add_table() again at this point, we must reinitialize the list_kref otherwise the kernel will hit a WARN() in kref infrastructure for incrementing a kref with value 0. Fixes: 11e1a1648298 ("opp: Don't decrement uninitialized list_kref") Reported-by: Dmitry Osipenko Tested-by: Dmitry Osipenko Signed-off-by: Viresh Kumar

opp: core: Revert "add regulators enable and disable"

2019-10-21T02:28:12Z

All the drivers, which use the OPP framework control regulators, which are already enabled. Typically those regulators are also system critical, due to providing power to CPU core or system buses. It turned out that there are cases, where calling regulator_enable() on such boot-enabled regulator has side-effects and might change its initial voltage due to performing initial voltage balancing without all restrictions from the consumers. Until this issue becomes finally solved in regulator core, avoid calling regulator_enable()/disable() from the OPP framework. This reverts commit 7f93ff73f7c8c8bfa6be33bcc16470b0b44682aa. Signed-off-by: Marek Szyprowski Reviewed-by: Mark Brown Signed-off-by: Viresh Kumar

opp: of: drop incorrect lockdep_assert_held()

2019-10-10T10:46:13Z

_find_opp_of_np() doesn't traverse the list of OPP tables but instead just the entries within an OPP table and so only requires to lock the OPP table itself. The lockdep_assert_held() was added there by mistake and isn't really required. Fixes: 5d6d106fa455 ("OPP: Populate required opp tables from "required-opps" property") Cc: v5.0+ # v5.0+ Reported-by: Niklas Cassel Signed-off-by: Viresh Kumar

opp: of: Support multiple suspend OPPs defined in DT

2019-07-26T07:55:52Z

With property "opp-supported-hw" introduced, the OPP table in DT could be a large OPP table and ONLY a subset of OPPs are available, based on the version of the hardware running on. That introduces restriction of using "opp-suspend" property to define the suspend OPP, as we are NOT sure if the OPP containing "opp-suspend" property is available for the hardware running on, and the of opp core does NOT allow multiple suspend OPPs defined in DT OPP table. To eliminate this restrition, make of opp core allow multiple suspend OPPs defined in DT, and pick the OPP with highest rate and with "opp-suspend" property present to be suspend OPP, it can speed up the suspend/resume process. Signed-off-by: Anson Huang Signed-off-by: Viresh Kumar