kernel/linux.git/drivers/base/power/opp, branch v4.14.263

opp: remove WARN when no valid OPPs remain

2021-09-03T07:56:25+00:00

[ Upstream commit 335ffab3ef864539e814b9a2903b0ae420c1c067 ] This WARN can be triggered per-core and the stack trace is not useful. Replace it with plain dev_err(). Fix a comment while at it. Signed-off-by: Michał Mirosław Signed-off-by: Viresh Kumar Signed-off-by: Sasha Levin

Revert "OPP: Protect dev_list with opp_table lock"

2019-11-24T07:22:45+00:00

This reverts commit 714ab224a8db6e8255c61a42613de9349ceb0bba which is commit 3d2556992a878a2210d3be498416aee39e0c32aa upstream. Turns out to break the build on the odroid machines, so it needs to be reverted. Reported-by: Viresh Kumar Reported-by: "kernelci.org bot" Cc: Niklas Cassel Cc: Sasha Levin Signed-off-by: Greg Kroah-Hartman

OPP: Protect dev_list with opp_table lock

2019-11-20T17:00:13+00:00

[ Upstream commit 3d2556992a878a2210d3be498416aee39e0c32aa ] The dev_list needs to be protected with a lock, else we may have simultaneous access (addition/removal) to it and that would be racy. Extend scope of the opp_table lock to protect dev_list as well. Tested-by: Niklas Cassel Signed-off-by: Viresh Kumar Signed-off-by: Sasha Levin

OPP: Use opp_table->regulators to verify no regulator case

2019-02-12T18:46:03+00:00

[ Upstream commit 90e3577b5feb42bac1269e16bb3d2bdd8f6df40f ] The value of opp_table->regulator_count is not very consistent right now and it may end up being 0 while we do have a "opp-microvolt" property in the OPP table. It was kept that way as we used to check if any regulators are set with the OPP core for a device or not using value of regulator_count. Lets use opp_table->regulators for that purpose as the meaning of regulator_count is going to change in the later patches. Reported-by: Quentin Perret Signed-off-by: Viresh Kumar Signed-off-by: Sasha Levin

PM / OPP: Update voltage in case freq == old_freq

2018-07-03T09:24:47+00:00

commit c5c2a97b3ac7d1ec19e7cff9e38caca6afefc3de upstream. This commit fixes a rare but possible case when the clk rate is updated without update of the regulator voltage. At boot up, CPUfreq checks if the system is running at the right freq. This is a sanity check in case a bootloader set clk rate that is outside of freq table present with cpufreq core. In such cases system can be unstable so better to change it to a freq that is preset in freq-table. The CPUfreq takes next freq that is >= policy->cur and this is our target_freq that needs to be set now. dev_pm_opp_set_rate(dev, target_freq) checks the target_freq and the old_freq (a current rate). If these are equal it returns early. If not, it searches for OPP (old_opp) that fits best to old_freq (not listed in the table) and updates old_freq (!). Here, we can end up with old_freq = old_opp.rate = target_freq, which is not handled in _generic_set_opp_regulator(). It's supposed to update voltage only when freq > old_freq || freq > old_freq. if (freq > old_freq) { ret = _set_opp_voltage(dev, reg, new_supply); [...] if (freq < old_freq) { ret = _set_opp_voltage(dev, reg, new_supply); if (ret) It results in, no voltage update while clk rate is updated. Example: freq-table = { 1000MHz 1.15V 666MHZ 1.10V 333MHz 1.05V } boot-up-freq = 800MHz # not listed in freq-table freq = target_freq = 1GHz old_freq = 800Mhz old_opp = _find_freq_ceil(opp_table, &old_freq); #(old_freq is modified!) old_freq = 1GHz Fixes: 6a0712f6f199 ("PM / OPP: Add dev_pm_opp_set_rate()") Cc: 4.6+ # v4.6+ Signed-off-by: Waldemar Rymarkiewicz Signed-off-by: Viresh Kumar Signed-off-by: Greg Kroah-Hartman

PM / OPP: Move error message to debug level

2017-12-25T13:26:26+00:00

[ Upstream commit 035ed07208dc501d023873447113f3f178592156 ] On some i.MX6 platforms which do not have speed grading check, opp table will not be created in platform code, so cpufreq driver prints the following error message: cpu cpu0: dev_pm_opp_get_opp_count: OPP table not found (-19) However, this is not really an error in this case because the imx6q-cpufreq driver first calls dev_pm_opp_get_opp_count() and if it fails, it means that platform code does not provide OPP and then dev_pm_opp_of_add_table() will be called. In order to avoid such confusing error message, move it to debug level. It is up to the caller of dev_pm_opp_get_opp_count() to check its return value and decide if it will print an error or not. Signed-off-by: Fabio Estevam Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

PM / OPP: Add missing of_node_put(np)

2017-11-30T08:40:41+00:00

commit 7978db344719dab1e56d05e6fc04aaaddcde0a5e upstream. The for_each_available_child_of_node() loop in _of_add_opp_table_v2() doesn't drop the reference to "np" on errors. Fix that. Fixes: 274659029c9d (PM / OPP: Add support to parse "operating-points-v2" bindings) Signed-off-by: Tobias Jordan [ VK: Improved commit log. ] Signed-off-by: Viresh Kumar Reviewed-by: Stephen Boyd Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

PM / OPP: Call notifier without holding opp_table->lock

2017-09-25T22:44:32+00:00

The notifier callbacks may want to call some OPP helper routines which may try to take the same opp_table->lock again and cause a deadlock. One such usecase was reported by Chanwoo Choi, where calling dev_pm_opp_disable() leads us to the devfreq's OPP notifier handler, which further calls dev_pm_opp_find_freq_floor() and it deadlocks. We don't really need the opp_table->lock to be held across the notifier call though, all we want to make sure is that the 'opp' doesn't get freed while being used from within the notifier chain. We can do it with help of dev_pm_opp_get/put() as well. Let's do it. Cc: 4.11+ # 4.11+ Fixes: 5b650b388844 "PM / OPP: Take kref from _find_opp_table()" Reported-by: Chanwoo Choi Tested-by: Chanwoo Choi Reviewed-by: Stephen Boyd Reviewed-by: Chanwoo Choi Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki

PM / OPP: Fix get sharing CPUs when hotplug is used

2017-08-01T12:10:55+00:00

We fail dev_pm_opp_of_get_sharing_cpus() when possible CPU device does not exist. This can happen on platforms where not all possible CPUs are available at start up ie. hotplugged out. The CPU device is not registered in the system so we are not able to check struct device to set the sharing CPUs bitmask properly. Example (real use case): 2 physical MIPS cores, 4 VPE, cpu0/2 run Linux and cpu1/3 are not available for Linux at boot up. cpufreq-dt driver + OPP v2 fail to register opp_table due to the fact there is no struct device for cpu1 (remains offline at bootup). To solve the bug, stop using device struct to check device_node. Instead get CPU device_node directly from device tree with of_get_cpu_node(). Signed-off-by: Waldemar Rymarkiewicz Acked-by: Viresh Kumar Reviewed-by: Stephen Boyd Signed-off-by: Rafael J. Wysocki

PM / OPP: OF: Use pr_debug() instead of pr_err() while adding OPP table

2017-07-16T00:24:33+00:00

Some platforms add the OPPs dynamically from platform specific drivers instead of getting them statically from DT. The cpufreq-dt driver already ignores the return value of dev_pm_opp_of_cpumask_add_table() to not error out for such cases, but we still end up printing error message from that routine. That's not nice. Convert the print message to use pr_debug() instead. Reported-by: Mason Signed-off-by: Viresh Kumar Reviewed-by: Stephen Boyd Signed-off-by: Rafael J. Wysocki