static int qcom_cpufreq_hw_read_lut()

in qcom-cpufreq-hw.c [147:245]

• 76 lines of code
• 16 McCabe index (conditional complexity)

static int qcom_cpufreq_hw_read_lut(struct device *cpu_dev,
				    struct cpufreq_policy *policy)
{
	u32 data, src, lval, i, core_count, prev_freq = 0, freq;
	u32 volt;
	struct cpufreq_frequency_table	*table;
	struct dev_pm_opp *opp;
	unsigned long rate;
	int ret;
	struct qcom_cpufreq_data *drv_data = policy->driver_data;
	const struct qcom_cpufreq_soc_data *soc_data = drv_data->soc_data;

	table = kcalloc(LUT_MAX_ENTRIES + 1, sizeof(*table), GFP_KERNEL);
	if (!table)
		return -ENOMEM;

	ret = dev_pm_opp_of_add_table(cpu_dev);
	if (!ret) {
		/* Disable all opps and cross-validate against LUT later */
		icc_scaling_enabled = true;
		for (rate = 0; ; rate++) {
			opp = dev_pm_opp_find_freq_ceil(cpu_dev, &rate);
			if (IS_ERR(opp))
				break;

			dev_pm_opp_put(opp);
			dev_pm_opp_disable(cpu_dev, rate);
		}
	} else if (ret != -ENODEV) {
		dev_err(cpu_dev, "Invalid opp table in device tree\n");
		return ret;
	} else {
		policy->fast_switch_possible = true;
		icc_scaling_enabled = false;
	}

	for (i = 0; i < LUT_MAX_ENTRIES; i++) {
		data = readl_relaxed(drv_data->base + soc_data->reg_freq_lut +
				      i * soc_data->lut_row_size);
		src = FIELD_GET(LUT_SRC, data);
		lval = FIELD_GET(LUT_L_VAL, data);
		core_count = FIELD_GET(LUT_CORE_COUNT, data);

		data = readl_relaxed(drv_data->base + soc_data->reg_volt_lut +
				      i * soc_data->lut_row_size);
		volt = FIELD_GET(LUT_VOLT, data) * 1000;

		if (src)
			freq = xo_rate * lval / 1000;
		else
			freq = cpu_hw_rate / 1000;

		if (freq != prev_freq && core_count != LUT_TURBO_IND) {
			if (!qcom_cpufreq_update_opp(cpu_dev, freq, volt)) {
				table[i].frequency = freq;
				dev_dbg(cpu_dev, "index=%d freq=%d, core_count %d\n", i,
				freq, core_count);
			} else {
				dev_warn(cpu_dev, "failed to update OPP for freq=%d\n", freq);
				table[i].frequency = CPUFREQ_ENTRY_INVALID;
			}

		} else if (core_count == LUT_TURBO_IND) {
			table[i].frequency = CPUFREQ_ENTRY_INVALID;
		}

		/*
		 * Two of the same frequencies with the same core counts means
		 * end of table
		 */
		if (i > 0 && prev_freq == freq) {
			struct cpufreq_frequency_table *prev = &table[i - 1];

			/*
			 * Only treat the last frequency that might be a boost
			 * as the boost frequency
			 */
			if (prev->frequency == CPUFREQ_ENTRY_INVALID) {
				if (!qcom_cpufreq_update_opp(cpu_dev, prev_freq, volt)) {
					prev->frequency = prev_freq;
					prev->flags = CPUFREQ_BOOST_FREQ;
				} else {
					dev_warn(cpu_dev, "failed to update OPP for freq=%d\n",
						 freq);
				}
			}

			break;
		}

		prev_freq = freq;
	}

	table[i].frequency = CPUFREQ_TABLE_END;
	policy->freq_table = table;
	dev_pm_opp_set_sharing_cpus(cpu_dev, policy->cpus);

	return 0;
}