问题
在sys文件系统下没有生成cpu 调频的相关节点。
日志对比
[ 3.588745] cpu cpu4: Looking up cpu-supply from device tree
[ 3.588753] cpu cpu4: Failed to get reg
[ 3.588791] cpu cpu4: Looking up cpu-supply from device tree
[ 3.588808] Failed to initialize dvfs info cpu4代码流程
cpufreq
kernel\drivers\soc\rockchip\rockchip_opp_select.c
static int rockchip_get_pvtm_pvtpll(struct device *dev, struct device_node *np,char *reg_name)
{struct regulator *reg;struct clk *clk;struct pvtm_config *pvtm;unsigned long old_freq;unsigned int old_volt;int cur_temp, diff_temp, prop_temp, diff_value;int pvtm_value = 0;int ret = 0;pvtm = kzalloc(sizeof(*pvtm), GFP_KERNEL);if (!pvtm)return -ENOMEM;ret = rockchip_parse_pvtm_config(np, pvtm);if (ret)goto out;clk = clk_get(dev, NULL);if (IS_ERR_OR_NULL(clk)) {dev_warn(dev, "Failed to get clk\n");goto out;}//如下这行打印出的失败信息reg = regulator_get_optional(dev, reg_name);if (IS_ERR_OR_NULL(reg)) {dev_warn(dev, "Failed to get reg\n");clk_put(clk);goto out;}I:\rk3588\kernel\drivers\cpufreq\rockchip-cpufreq.c
static int rockchip_cpufreq_cluster_init(int cpu, struct cluster_info *cluster)
{struct rockchip_opp_info *opp_info = &cluster->opp_info;struct opp_table *pname_table = NULL;struct opp_table *reg_table = NULL;if (opp_info->data && opp_info->data->get_soc_info)opp_info->data->get_soc_info(dev, np, &bin, &process);rockchip_get_scale_volt_sel(dev, "cpu_leakage", reg_name, bin, process,&cluster->scale, &volt_sel); //入口函数static int __init rockchip_cpufreq_driver_init(void)
{struct cluster_info *cluster, *pos;struct cpufreq_dt_platform_data pdata = {0};int cpu, ret;for_each_possible_cpu(cpu) {cluster = rockchip_cluster_info_lookup(cpu);if (cluster)continue;cluster = kzalloc(sizeof(*cluster), GFP_KERNEL);if (!cluster) {ret = -ENOMEM;goto release_cluster_info;}ret = rockchip_cpufreq_cluster_init(cpu, cluster);if (ret) {pr_err("Failed to initialize dvfs info cpu%d\n", cpu);goto release_cluster_info;}list_add(&cluster->list_head, &cluster_info_list);}regulator
_regulator_get
I:\rk3588\kernel\drivers\regulator\core.c
根据此函数，猜测由于regulator设备没有被发现，没有被注册到系统中，导致cpufreq没有找到相应的regulator节点。
rk806
I:\rk3588\kernel\drivers\regulator\rk806-regulator.c
rk860
I:\rk3588\kernel\drivers\regulator\rk860x-regulator.c
DTS配置
&i2c0 {status = "okay";pinctrl-names = "default";pinctrl-0 = <&i2c0m2_xfer>;vdd_cpu_big0_s0: vdd_cpu_big0_mem_s0: rk8602@42 {compatible = "rockchip,rk8602";reg = <0x42>;vin-supply = <&vcc5v0_sys>;vsel-gpios = <&gpio0 RK_PA3 GPIO_ACTIVE_HIGH>;regulator-compatible = "rk860x-reg";regulator-name = "vdd_cpu_big0_s0";regulator-min-microvolt = <550000>;regulator-max-microvolt = <1050000>;regulator-ramp-delay = <2300>;rockchip,suspend-voltage-selector = <1>;regulator-boot-on;regulator-always-on;regulator-state-mem {regulator-off-in-suspend;};};sys节点创建
rk860x_regulator_register--》devm_regulator_register->regulator_register
-->rdev_init_debugfs-->
此处没有创建设备节点，也就是前面初始化部分出现问题了。
初始化代码
/* Get chip ID */ret = regmap_read(di->regmap, RK860X_ID1, &val);if (ret < 0) {dev_err(&client->dev, "Failed to get chip ID!\n");return ret;}switch (di->chip_id) {case RK860X_CHIP_ID_00:case RK860X_CHIP_ID_01:if ((val & DIE_ID) != 0x8) {dev_err(&client->dev, "Failed to match chip ID!\n");return -EINVAL;}break;case RK860X_CHIP_ID_02:case RK860X_CHIP_ID_03:if ((val & DIE_ID) != 0xa) {dev_err(&client->dev, "Failed to match chip ID!\n");return -EINVAL;}break;default:return -EINVAL;}/* Device init */ret = rk860x_device_setup(di, pdata);if (ret < 0) {dev_err(&client->dev, "Failed to setup device!\n");return ret;}/* Register regulator */config.dev = di->dev;config.init_data = di->regulator;config.regmap = di->regmap;config.driver_data = di;config.of_node = np;ret = rk860x_regulator_register(di, &config);if (ret < 0)dev_err(&client->dev, "Failed to register regulator!\n");
回看dmesg日志
[ 3.509295] i2c /dev entries driver
[ 3.510437] rk860-regulator 0-0042: Failed to match chip ID!
[ 3.510478] rk860-regulator: probe of 0-0042 failed with error -22
[ 3.511089] rk860-regulator 0-0043: Failed to match chip ID!
[ 3.511120] rk860-regulator: probe of 0-0043 failed with error -22
[ 3.514659] rk860-regulator 1-0042: Looking up vin-supply from device tree对比正常日志
也就是从I2C读取的ID 信息不对。
读取偏移量为0x3
sys文件系统调试信息
regulator summary
查看只有 vdd_cpu_lit_s0 没有两个大核的信息，可以确认两个大核对应的regulator没有生成。
cat /sys/kernel/debug/regulator/regulator_summaryregulator use open bypass opmode voltage current min max
---------------------------------------------------------------------------------------regulator-dummy 4 4 0 unknown 0mV 0mA 0mV 0mVfe210000.sata-target 1 0mA 0mV 0mVfe210000.sata-phy 1 0mA 0mV 0mVfe210000.sata-ahci 1 0mA 0mV 0mVregulator-dummy 0 0mA 0mV 0mVvcc12v_dcin 3 3 0 unknown 12000mV 0mA 12000mV 12000mVvcc12v_dcin 0 0mA 0mV 0mVvcc5v0_sys 16 16 0 unknown 5000mV 0mA 5000mV 5000mVvcc5v0_sys 0 0mA 0mV 0mVvcc_1v1_nldo_s3 6 6 0 unknown 1100mV 0mA 1100mV 1100mVvcc_1v1_nldo_s3 0 0mA 0mV 0mVvdd_0v75_s3 1 1 0 unknown 750mV 0mA 750mV 750mVvdd_0v75_s3 0 0mA 0mV 0mVvdd_ddr_pll_s0 1 1 0 unknown 850mV 0mA 850mV 850mVvdd_ddr_pll_s0 0 0mA 0mV 0mVavdd_0v75_s0 2 2 0 unknown 750mV 0mA 750mV 750mVavdd_0v75_s0 0 0mA 0mV 0mVpcie30_avdd0v75 1 1 0 unknown 750mV 0mA 750mV 750mVpcie30_avdd0v75 0 0mA 0mV 0mVvdd_0v85_s0 2 2 0 unknown 850mV 0mA 850mV 850mVvdd_0v85_s0 0 0mA 0mV 0mVpcie20_avdd0v85 1 1 0 unknown 850mV 0mA 850mV 850mVpcie20_avdd0v85 0 0mA 0mV 0mVvdd_0v75_s0 1 1 0 unknown 750mV 0mA 750mV 750mVvdd_0v75_s0 0 0mA 0mV 0mVvdd_gpu_s0 0 5 0 normal 675mV 0mA 550mV 950mVfb000000.gpu-mem 0 0mA 675mV 950mVfb000000.gpu-mali 0 0mA 675mV 950mVfb000000.gpu-mem 0 0mA 0mV 0mVfb000000.gpu-mali 0 0mA 0mV 0mVvdd_gpu_s0 0 0mA 0mV 0mVvdd_cpu_lit_s0 1 3 0 normal 750mV 0mA 550mV 950mVcpu0-mem 0 0mA 0mV 0mVcpu0-cpu 0 0mA 0mV 0mVvdd_cpu_lit_s0 0 0mA 0mV 0mVvdd_log_s0 1 1 0 normal 750mV 0mA 675mV 750mVvdd_log_s0 0 0mA 0mV 0mVvdd_vdenc_s0 1 1 0 normal 750mV 0mA 550mV 950mVvdd_vdenc_s0 0 0mA 0mV 0mVvdd_ddr_s0 1 1 0 normal 850mV 0mA 675mV 900mVvdd_ddr_s0 0 0mA 0mV 0mVvdd2_ddr_s3 1 1 0 normal 500mV 0mA 0mV 0mVvdd2_ddr_s3 0 0mA 0mV 0mVvdd_2v0_pldo_s3 4 4 0 normal 2000mV 0mA 2000mV 2000mVvdd_2v0_pldo_s3 0 0mA 0mV 0mVavcc_1v8_s0 3 3 0 unknown 1800mV 0mA 1800mV 1800mVavcc_1v8_s0 0 0mA 0mV 0mVpcie30_avdd1v8 1 1 0 unknown 1800mV 0mA 1800mV 1800mVpcie30_avdd1v8 0 0mA 0mV 0mVpcie20_avdd1v8 1 1 0 unknown 1800mV 0mA 1800mV 1800mVpcie20_avdd1v8 0 0mA 0mV 0mVvcc_1v8_s0 2 2 0 unknown 1800mV 0mA 1800mV 1800mVfec10000.saradc-vref 1 0mA 0mV 0mVvcc_1v8_s0 0 0mA 0mV 0mVavdd_1v2_s0 1 1 0 unknown 1200mV 0mA 1200mV 1200mVavdd_1v2_s0 0 0mA 0mV 0mVvcc_3v3_s3 1 1 0 normal 3300mV 0mA 3300mV 3300mVvcc_3v3_s3 0 0mA 0mV 0mVvddq_ddr_s0 1 1 0 normal 500mV 0mA 0mV 0mVvddq_ddr_s0 0 0mA 0mV 0mVvcc_1v8_s3 1 1 0 normal 1800mV 0mA 1800mV 1800mVvcc_1v8_s3 0 0mA 0mV 0mVvcc_3v3_s0 1 1 0 unknown 3300mV 0mA 3300mV 3300mVvcc_3v3_s0 0 0mA 0mV 0mVvccio_sd_s0 1 1 0 unknown 3300mV 0mA 1800mV 3300mVvccio_sd_s0 0 0mA 0mV 0mVpldo6_s3 1 1 0 unknown 1800mV 0mA 1800mV 1800mVpldo6_s3 0 0mA 0mV 0mVvdd_npu_s0 1 5 0 normal 825mV 0mA 550mV 950mVfdab0000.npu-mem 0 0mA 825mV 950mVfdab0000.npu-rknpu 0 0mA 825mV 950mVfdab0000.npu-mem 0 0mA 0mV 0mVfdab0000.npu-rknpu 0 0mA 0mV 0mVvdd_npu_s0 0 0mA 0mV 0mVvcc5v0_usbdcin 2 2 0 unknown 5000mV 0mA 5000mV 5000mVvcc5v0_usbdcin 0 0mA 0mV 0mVvcc5v0_usb 1 2 0 unknown 5000mV 0mA 5000mV 5000mVvcc5v0_usb 0 0mA 0mV 0mVvbus5v0_typec 0 2 0 unknown 5000mV 0mA 5000mV 5000mV6-0022-vbus 0 0mA 0mV 0mVvbus5v0_typec 0 0mA 0mV 0mV
总结
至此，我们找到了sys cpufreq没有生成的根因。由于I2C的问题，导致regulator未生成，进而导致cpufreq在初始化时，查找对应的regulator失败。导致cpufreq相关节点没有生成。
进一步的问题
如果cpufreq没有初始化成功，那么CPU的工作频率是多少？
