The SCMI protocol can be used to get power estimates from firmware corresponding to each performance state of a device. Although these power costs are already managed by the SCMI firmware driver, they are not exposed to any external subsystem yet.
Fix this by adding a new get_power() interface to the exisiting perf_ops defined for the SCMI protocol. Signed-off-by: Quentin Perret <[email protected]> --- v2: rebased on 4.19-rc2 --- drivers/firmware/arm_scmi/perf.c | 28 ++++++++++++++++++++++++++++ include/linux/scmi_protocol.h | 4 ++++ 2 files changed, 32 insertions(+) diff --git a/drivers/firmware/arm_scmi/perf.c b/drivers/firmware/arm_scmi/perf.c index 721e6c57beae..272abd2cb3f0 100644 --- a/drivers/firmware/arm_scmi/perf.c +++ b/drivers/firmware/arm_scmi/perf.c @@ -421,6 +421,33 @@ static int scmi_dvfs_freq_get(const struct scmi_handle *handle, u32 domain, return ret; } +static int scmi_dvfs_power_get(const struct scmi_handle *handle, u32 domain, + unsigned long *freq, unsigned long *power) +{ + struct scmi_perf_info *pi = handle->perf_priv; + struct perf_dom_info *dom; + unsigned long opp_freq; + int idx, ret = -EINVAL; + struct scmi_opp *opp; + + dom = pi->dom_info + domain; + if (!dom) + return -EIO; + + for (opp = dom->opp, idx = 0; idx < dom->opp_count; idx++, opp++) { + opp_freq = opp->perf * dom->mult_factor; + if (opp_freq < *freq) + continue; + + *freq = opp_freq; + *power = opp->power; + ret = 0; + break; + } + + return ret; +} + static struct scmi_perf_ops perf_ops = { .limits_set = scmi_perf_limits_set, .limits_get = scmi_perf_limits_get, @@ -431,6 +458,7 @@ static struct scmi_perf_ops perf_ops = { .device_opps_add = scmi_dvfs_device_opps_add, .freq_set = scmi_dvfs_freq_set, .freq_get = scmi_dvfs_freq_get, + .power_get = scmi_dvfs_power_get, }; static int scmi_perf_protocol_init(struct scmi_handle *handle) diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h index f4c9fc0fc755..2ecbd2c5a249 100644 --- a/include/linux/scmi_protocol.h +++ b/include/linux/scmi_protocol.h @@ -91,6 +91,8 @@ struct scmi_clk_ops { * to sustained performance level mapping * @freq_get: gets the frequency for a given device using sustained frequency * to sustained performance level mapping + * @power_get: gets the power dissipated for a given performance domain at a + * given frequency */ struct scmi_perf_ops { int (*limits_set)(const struct scmi_handle *handle, u32 domain, @@ -110,6 +112,8 @@ struct scmi_perf_ops { unsigned long rate, bool poll); int (*freq_get)(const struct scmi_handle *handle, u32 domain, unsigned long *rate, bool poll); + int (*power_get)(const struct scmi_handle *handle, u32 domain, + unsigned long *rate, unsigned long *power); }; /** -- 2.17.1
