Re: [PATCH v10 1/2] cpufreq: Add Kryo CPU scaling driver

Viresh Kumar
2018-05-23T10:03:23Z

On 23-05-18, 12:40, Ilia Lin wrote:
> In Certain QCOM SoCs like apq8096 and msm8996 that have KRYO processors,
> the CPU frequency subset and voltage value of each OPP varies
> based on the silicon variant in use. Qualcomm Process Voltage Scaling Tables
> defines the voltage and frequency value based on the msm-id in SMEM
> and speedbin blown in the efuse combination.
> The qcom-cpufreq-kryo driver reads the msm-id and efuse value from the SoC
> to provide the OPP framework with required information.
> This is used to determine the voltage and frequency value for each OPP of
> operating-points-v2 table when it is parsed by the OPP framework.
>
> Signed-off-by: Ilia Lin <ilialin@codeaurora.org>

Well I gave you an Ack and you should have kept it here :(

> +static int __init qcom_cpufreq_kryo_driver_init(void)
> +{
> + struct opp_table *opp_tables[NR_CPUS] = {0};
> + enum _msm8996_version msm8996_version;
> + struct nvmem_cell *speedbin_nvmem;
> + struct platform_device *pdev;
> + struct device_node *np;
> + struct device *cpu_dev;
> + unsigned cpu;
> + u8 *speedbin;
> + u32 versions;
> + size_t len;
> + int ret;
> +
> + cpu_dev = get_cpu_device(0);
> + if (NULL == cpu_dev)
> + return -ENODEV;
> +
> + msm8996_version = qcom_cpufreq_kryo_get_msm_id();
> + if (NUM_OF_MSM8996_VERSIONS == msm8996_version) {
> + dev_err(cpu_dev, "Not Snapdragon 820/821!");
> + return -ENODEV;
> + }
> +
> + np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
> + if (IS_ERR(np))
> + return PTR_ERR(np);
> +
> + if (!of_device_is_compatible(np, "operating-points-v2-kryo-cpu")) {
> + ret = -ENOENT;
> + goto free_np;

As Russell pointed out, drop this goto here and write:

of_node_put(np);
return -ENOENT;
}

> + }
> +
> + speedbin_nvmem = of_nvmem_cell_get(np, NULL);

And do the same here unconditionally as you don't need to use np
anymore, i.e.

of_node_put(np);

> + if (IS_ERR(speedbin_nvmem)) {
> + ret = PTR_ERR(speedbin_nvmem);
> + dev_err(cpu_dev, "Could not get nvmem cell: %d\n", ret);
> + goto free_np;
> + }
> +
> + speedbin = nvmem_cell_read(speedbin_nvmem, &len);
> + nvmem_cell_put(speedbin_nvmem);
> +
> + switch (msm8996_version) {
> + case MSM8996_V3:
> + versions = 1 << (unsigned int)(*speedbin);
> + break;
> + case MSM8996_SG:
> + versions = 1 << ((unsigned int)(*speedbin) + 4);
> + break;
> + default:
> + BUG();
> + break;
> + }
> +
> + for_each_possible_cpu(cpu) {
> + cpu_dev = get_cpu_device(cpu);
> + if (NULL == cpu_dev) {
> + ret = -ENODEV;
> + goto free_opp;
> + }
> +
> + opp_tables[cpu] = dev_pm_opp_set_supported_hw(cpu_dev,
> + &versions, 1);
> + if (IS_ERR(opp_tables[cpu])) {
> + ret = PTR_ERR(opp_tables[cpu]);
> + dev_err(cpu_dev, "Failed to set supported hardware\n");
> + goto free_opp;
> + }
> + }
> +
> + pdev = platform_device_register_simple("cpufreq-dt", -1, NULL, 0);
> + if (!IS_ERR(pdev))
> + return 0;
> +
> + ret = PTR_ERR(pdev);
> + dev_err(cpu_dev, "Failed to register platform device\n");
> +
> +free_opp:
> + for_each_possible_cpu(cpu) {
> + if (IS_ERR_OR_NULL(opp_tables[cpu]))
> + break;
> + dev_pm_opp_put_supported_hw(opp_tables[cpu]);
> + }
> +free_np:
> + of_node_put(np);

And then you can remove the label and above statement.

> +
> + return ret;
> +}
> +late_initcall(qcom_cpufreq_kryo_driver_init);
> +
> +MODULE_DESCRIPTION("Qualcomm Technologies, Inc. Kryo CPUfreq driver");
> +MODULE_LICENSE("GPL v2");
> --
> 1.9.1

--
viresh