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| author | Viresh Kumar <viresh.kumar@linaro.org> | 2023-10-27 12:40:04 +0530 |
|---|---|---|
| committer | Viresh Kumar <viresh.kumar@linaro.org> | 2023-11-28 16:03:04 +0530 |
| commit | 073d3d2ca7d462afc8159ca0175675b9b7b4f162 (patch) | |
| tree | 3cfa67ed8a9901682bb8b14e4634e47968d32466 /drivers/opp | |
| parent | 4c58e9d85c24b5281a2d39a3e6510b5f3b7fc687 (diff) | |
| download | lwn-073d3d2ca7d462afc8159ca0175675b9b7b4f162.tar.gz lwn-073d3d2ca7d462afc8159ca0175675b9b7b4f162.zip | |
OPP: Level zero is valid
The level zero can be used by some OPPs to drop performance state vote
for the device. It is perfectly fine to allow the same.
_set_opp_level() considers it as an invalid value currently and returns
early.
In order to support this properly, initialize the level field with
U32_MAX, which denotes unused level field.
Reported-by: Stephan Gerhold <stephan.gerhold@kernkonzept.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Stephan Gerhold <stephan.gerhold@kernkonzept.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Diffstat (limited to 'drivers/opp')
| -rw-r--r-- | drivers/opp/core.c | 24 | ||||
| -rw-r--r-- | drivers/opp/of.c | 8 |
2 files changed, 27 insertions, 5 deletions
diff --git a/drivers/opp/core.c b/drivers/opp/core.c index 84f345c69ea5..f2e2aa07b431 100644 --- a/drivers/opp/core.c +++ b/drivers/opp/core.c @@ -201,7 +201,7 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_get_freq_indexed); * @opp: opp for which level value has to be returned for * * Return: level read from device tree corresponding to the opp, else - * return 0. + * return U32_MAX. */ unsigned int dev_pm_opp_get_level(struct dev_pm_opp *opp) { @@ -221,7 +221,7 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_get_level); * @index: index of the required opp * * Return: performance state read from device tree corresponding to the - * required opp, else return 0. + * required opp, else return U32_MAX. */ unsigned int dev_pm_opp_get_required_pstate(struct dev_pm_opp *opp, unsigned int index) @@ -808,6 +808,14 @@ struct dev_pm_opp *dev_pm_opp_find_level_ceil(struct device *dev, struct dev_pm_opp *opp; opp = _find_key_ceil(dev, &temp, 0, true, _read_level, NULL); + + /* False match */ + if (temp == OPP_LEVEL_UNSET) { + dev_err(dev, "%s: OPP levels aren't available\n", __func__); + dev_pm_opp_put(opp); + return ERR_PTR(-ENODEV); + } + *level = temp; return opp; } @@ -1049,12 +1057,18 @@ static int _set_opp_bw(const struct opp_table *opp_table, static int _set_performance_state(struct device *dev, struct device *pd_dev, struct dev_pm_opp *opp, int i) { - unsigned int pstate = likely(opp) ? opp->required_opps[i]->level: 0; + unsigned int pstate = 0; int ret; if (!pd_dev) return 0; + if (likely(opp)) { + pstate = opp->required_opps[i]->level; + if (pstate == OPP_LEVEL_UNSET) + return 0; + } + ret = dev_pm_domain_set_performance_state(pd_dev, pstate); if (ret) { dev_err(dev, "Failed to set performance state of %s: %d (%d)\n", @@ -1135,7 +1149,7 @@ static int _set_opp_level(struct device *dev, struct opp_table *opp_table, int ret = 0; if (opp) { - if (!opp->level) + if (opp->level == OPP_LEVEL_UNSET) return 0; level = opp->level; @@ -1867,6 +1881,8 @@ struct dev_pm_opp *_opp_allocate(struct opp_table *opp_table) INIT_LIST_HEAD(&opp->node); + opp->level = OPP_LEVEL_UNSET; + return opp; } diff --git a/drivers/opp/of.c b/drivers/opp/of.c index 81fa27599d58..85fad7ca0007 100644 --- a/drivers/opp/of.c +++ b/drivers/opp/of.c @@ -1393,8 +1393,14 @@ int of_get_required_opp_performance_state(struct device_node *np, int index) opp = _find_opp_of_np(opp_table, required_np); if (opp) { - pstate = opp->level; + if (opp->level == OPP_LEVEL_UNSET) { + pr_err("%s: OPP levels aren't available for %pOF\n", + __func__, np); + } else { + pstate = opp->level; + } dev_pm_opp_put(opp); + } dev_pm_opp_put_opp_table(opp_table); |