@@ -57,6 +57,41 @@ static const struct of_device_id cpu_opp_match_list[] = {
{}
};
+/**
+ * dt_has_supported_hw() - Check if any OPPs use opp-supported-hw
+ *
+ * If we ask the cpufreq framework to use the opp-supported-hw feature, it
+ * will ignore every OPP node without that DT property. If none of the OPPs
+ * have it, the driver will fail probing, due to the lack of OPPs.
+ *
+ * Returns true if we have at least one OPP with the opp-supported-hw property.
+ */
+static bool dt_has_supported_hw(void)
+{
+ bool has_opp_supported_hw = false;
+ struct device_node *np, *opp;
+ struct device *cpu_dev;
+
+ cpu_dev = get_cpu_device(0);
+ if (!cpu_dev)
+ return -ENODEV;
+
+ np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
+ if (!np)
+ return -ENOENT;
+
+ for_each_child_of_node(np, opp) {
+ if (of_find_property(opp, "opp-supported-hw", NULL)) {
+ has_opp_supported_hw = true;
+ break;
+ }
+ }
+
+ of_node_put(np);
+
+ return has_opp_supported_hw;
+}
+
/**
* sun50i_cpufreq_get_efuse() - Determine speed grade from efuse value
*
@@ -110,7 +145,8 @@ static int sun50i_cpufreq_nvmem_probe(struct platform_device *pdev)
{
int *opp_tokens;
char name[MAX_NAME_LEN];
- unsigned int cpu;
+ unsigned int cpu, supported_hw;
+ struct dev_pm_opp_config config = {};
int speed;
int ret;
@@ -125,7 +161,18 @@ static int sun50i_cpufreq_nvmem_probe(struct platform_device *pdev)
return speed;
}
+ /*
+ * We need at least one OPP with the "opp-supported-hw" property,
+ * or else the upper layers will ignore every OPP and will bail out.
+ */
+ if (dt_has_supported_hw()) {
+ supported_hw = 1U << speed;
+ config.supported_hw = &supported_hw;
+ config.supported_hw_count = 1;
+ }
+
snprintf(name, MAX_NAME_LEN, "speed%d", speed);
+ config.prop_name = name;
for_each_possible_cpu(cpu) {
struct device *cpu_dev = get_cpu_device(cpu);
@@ -135,12 +182,11 @@ static int sun50i_cpufreq_nvmem_probe(struct platform_device *pdev)
goto free_opp;
}
- opp_tokens[cpu] = dev_pm_opp_set_prop_name(cpu_dev, name);
- if (opp_tokens[cpu] < 0) {
- ret = opp_tokens[cpu];
- pr_err("Failed to set prop name\n");
+ ret = dev_pm_opp_set_config(cpu_dev, &config);
+ if (ret < 0)
goto free_opp;
- }
+
+ opp_tokens[cpu] = ret;
}
cpufreq_dt_pdev = platform_device_register_simple("cpufreq-dt", -1,
@@ -155,7 +201,7 @@ static int sun50i_cpufreq_nvmem_probe(struct platform_device *pdev)
free_opp:
for_each_possible_cpu(cpu)
- dev_pm_opp_put_prop_name(opp_tokens[cpu]);
+ dev_pm_opp_clear_config(opp_tokens[cpu]);
kfree(opp_tokens);
return ret;
@@ -169,7 +215,7 @@ static void sun50i_cpufreq_nvmem_remove(struct platform_device *pdev)
platform_device_unregister(cpufreq_dt_pdev);
for_each_possible_cpu(cpu)
- dev_pm_opp_put_prop_name(opp_tokens[cpu]);
+ dev_pm_opp_clear_config(opp_tokens[cpu]);
kfree(opp_tokens);
}
The opp_supported_hw DT property allows the DT to specify a mask of chip revisions that a certain OPP is eligible for. This allows for easy limiting of maximum frequencies, for instance. Add support for that in the sun50i-cpufreq-nvmem driver. We support both the existing opp-microvolt suffix properties as well as the opp-supported-hw property, the generic code figures out which is needed automatically. However if none of the DT OPP nodes contain an opp-supported-hw property, the core code will ignore all OPPs and the driver will fail probing. So check the DT's eligibility first before using that feature. Signed-off-by: Andre Przywara <andre.przywara@arm.com> --- drivers/cpufreq/sun50i-cpufreq-nvmem.c | 62 ++++++++++++++++++++++---- 1 file changed, 54 insertions(+), 8 deletions(-)