linux 内核regulator
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_summary
regulator use open bypass opmode voltage current min max
---------------------------------------------------------------------------------------
regulator-dummy 4 4 0 unknown 0mV 0mA 0mV 0mV
fe210000.sata-target 1 0mA 0mV 0mV
fe210000.sata-phy 1 0mA 0mV 0mV
fe210000.sata-ahci 1 0mA 0mV 0mV
regulator-dummy 0 0mA 0mV 0mV
vcc12v_dcin 3 3 0 unknown 12000mV 0mA 12000mV 12000mV
vcc12v_dcin 0 0mA 0mV 0mV
vcc5v0_sys 16 16 0 unknown 5000mV 0mA 5000mV 5000mV
vcc5v0_sys 0 0mA 0mV 0mV
vcc_1v1_nldo_s3 6 6 0 unknown 1100mV 0mA 1100mV 1100mV
vcc_1v1_nldo_s3 0 0mA 0mV 0mV
vdd_0v75_s3 1 1 0 unknown 750mV 0mA 750mV 750mV
vdd_0v75_s3 0 0mA 0mV 0mV
vdd_ddr_pll_s0 1 1 0 unknown 850mV 0mA 850mV 850mV
vdd_ddr_pll_s0 0 0mA 0mV 0mV
avdd_0v75_s0 2 2 0 unknown 750mV 0mA 750mV 750mV
avdd_0v75_s0 0 0mA 0mV 0mV
pcie30_avdd0v75 1 1 0 unknown 750mV 0mA 750mV 750mV
pcie30_avdd0v75 0 0mA 0mV 0mV
vdd_0v85_s0 2 2 0 unknown 850mV 0mA 850mV 850mV
vdd_0v85_s0 0 0mA 0mV 0mV
pcie20_avdd0v85 1 1 0 unknown 850mV 0mA 850mV 850mV
pcie20_avdd0v85 0 0mA 0mV 0mV
vdd_0v75_s0 1 1 0 unknown 750mV 0mA 750mV 750mV
vdd_0v75_s0 0 0mA 0mV 0mV
vdd_gpu_s0 0 5 0 normal 675mV 0mA 550mV 950mV
fb000000.gpu-mem 0 0mA 675mV 950mV
fb000000.gpu-mali 0 0mA 675mV 950mV
fb000000.gpu-mem 0 0mA 0mV 0mV
fb000000.gpu-mali 0 0mA 0mV 0mV
vdd_gpu_s0 0 0mA 0mV 0mV
vdd_cpu_lit_s0 1 3 0 normal 750mV 0mA 550mV 950mV
cpu0-mem 0 0mA 0mV 0mV
cpu0-cpu 0 0mA 0mV 0mV
vdd_cpu_lit_s0 0 0mA 0mV 0mV
vdd_log_s0 1 1 0 normal 750mV 0mA 675mV 750mV
vdd_log_s0 0 0mA 0mV 0mV
vdd_vdenc_s0 1 1 0 normal 750mV 0mA 550mV 950mV
vdd_vdenc_s0 0 0mA 0mV 0mV
vdd_ddr_s0 1 1 0 normal 850mV 0mA 675mV 900mV
vdd_ddr_s0 0 0mA 0mV 0mV
vdd2_ddr_s3 1 1 0 normal 500mV 0mA 0mV 0mV
vdd2_ddr_s3 0 0mA 0mV 0mV
vdd_2v0_pldo_s3 4 4 0 normal 2000mV 0mA 2000mV 2000mV
vdd_2v0_pldo_s3 0 0mA 0mV 0mV
avcc_1v8_s0 3 3 0 unknown 1800mV 0mA 1800mV 1800mV
avcc_1v8_s0 0 0mA 0mV 0mV
pcie30_avdd1v8 1 1 0 unknown 1800mV 0mA 1800mV 1800mV
pcie30_avdd1v8 0 0mA 0mV 0mV
pcie20_avdd1v8 1 1 0 unknown 1800mV 0mA 1800mV 1800mV
pcie20_avdd1v8 0 0mA 0mV 0mV
vcc_1v8_s0 2 2 0 unknown 1800mV 0mA 1800mV 1800mV
fec10000.saradc-vref 1 0mA 0mV 0mV
vcc_1v8_s0 0 0mA 0mV 0mV
avdd_1v2_s0 1 1 0 unknown 1200mV 0mA 1200mV 1200mV
avdd_1v2_s0 0 0mA 0mV 0mV
vcc_3v3_s3 1 1 0 normal 3300mV 0mA 3300mV 3300mV
vcc_3v3_s3 0 0mA 0mV 0mV
vddq_ddr_s0 1 1 0 normal 500mV 0mA 0mV 0mV
vddq_ddr_s0 0 0mA 0mV 0mV
vcc_1v8_s3 1 1 0 normal 1800mV 0mA 1800mV 1800mV
vcc_1v8_s3 0 0mA 0mV 0mV
vcc_3v3_s0 1 1 0 unknown 3300mV 0mA 3300mV 3300mV
vcc_3v3_s0 0 0mA 0mV 0mV
vccio_sd_s0 1 1 0 unknown 3300mV 0mA 1800mV 3300mV
vccio_sd_s0 0 0mA 0mV 0mV
pldo6_s3 1 1 0 unknown 1800mV 0mA 1800mV 1800mV
pldo6_s3 0 0mA 0mV 0mV
vdd_npu_s0 1 5 0 normal 825mV 0mA 550mV 950mV
fdab0000.npu-mem 0 0mA 825mV 950mV
fdab0000.npu-rknpu 0 0mA 825mV 950mV
fdab0000.npu-mem 0 0mA 0mV 0mV
fdab0000.npu-rknpu 0 0mA 0mV 0mV
vdd_npu_s0 0 0mA 0mV 0mV
vcc5v0_usbdcin 2 2 0 unknown 5000mV 0mA 5000mV 5000mV
vcc5v0_usbdcin 0 0mA 0mV 0mV
vcc5v0_usb 1 2 0 unknown 5000mV 0mA 5000mV 5000mV
vcc5v0_usb 0 0mA 0mV 0mV
vbus5v0_typec 0 2 0 unknown 5000mV 0mA 5000mV 5000mV
6-0022-vbus 0 0mA 0mV 0mV
vbus5v0_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？