diff options
Diffstat (limited to 'drivers/cpufreq/qcom-cpufreq-kryo.c')
| -rw-r--r-- | drivers/cpufreq/qcom-cpufreq-kryo.c | 212 |
1 files changed, 212 insertions, 0 deletions
diff --git a/drivers/cpufreq/qcom-cpufreq-kryo.c b/drivers/cpufreq/qcom-cpufreq-kryo.c new file mode 100644 index 000000000000..d049fe4b80c4 --- /dev/null +++ b/drivers/cpufreq/qcom-cpufreq-kryo.c @@ -0,0 +1,212 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2018, The Linux Foundation. All rights reserved. + */ + +/* + * 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. + */ + +#include <linux/cpu.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/nvmem-consumer.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm_opp.h> +#include <linux/slab.h> +#include <linux/soc/qcom/smem.h> + +#define MSM_ID_SMEM 137 + +enum _msm_id { + MSM8996V3 = 0xF6ul, + APQ8096V3 = 0x123ul, + MSM8996SG = 0x131ul, + APQ8096SG = 0x138ul, +}; + +enum _msm8996_version { + MSM8996_V3, + MSM8996_SG, + NUM_OF_MSM8996_VERSIONS, +}; + +static enum _msm8996_version __init qcom_cpufreq_kryo_get_msm_id(void) +{ + size_t len; + u32 *msm_id; + enum _msm8996_version version; + + msm_id = qcom_smem_get(QCOM_SMEM_HOST_ANY, MSM_ID_SMEM, &len); + if (IS_ERR(msm_id)) + return NUM_OF_MSM8996_VERSIONS; + + /* The first 4 bytes are format, next to them is the actual msm-id */ + msm_id++; + + switch ((enum _msm_id)*msm_id) { + case MSM8996V3: + case APQ8096V3: + version = MSM8996_V3; + break; + case MSM8996SG: + case APQ8096SG: + version = MSM8996_SG; + break; + default: + version = NUM_OF_MSM8996_VERSIONS; + } + + return version; +} + +static int qcom_cpufreq_kryo_probe(struct platform_device *pdev) +{ + struct opp_table *opp_tables[NR_CPUS] = {0}; + struct platform_device *cpufreq_dt_pdev; + enum _msm8996_version msm8996_version; + struct nvmem_cell *speedbin_nvmem; + 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) + ret = -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); + + ret = of_device_is_compatible(np, "operating-points-v2-kryo-cpu"); + if (!ret) { + of_node_put(np); + return -ENOENT; + } + + speedbin_nvmem = of_nvmem_cell_get(np, NULL); + of_node_put(np); + if (IS_ERR(speedbin_nvmem)) { + dev_err(cpu_dev, "Could not get nvmem cell: %ld\n", + PTR_ERR(speedbin_nvmem)); + return PTR_ERR(speedbin_nvmem); + } + + 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; + } + } + + cpufreq_dt_pdev = platform_device_register_simple("cpufreq-dt", -1, + NULL, 0); + if (!IS_ERR(cpufreq_dt_pdev)) + return 0; + + ret = PTR_ERR(cpufreq_dt_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]); + } + + return ret; +} + +static struct platform_driver qcom_cpufreq_kryo_driver = { + .probe = qcom_cpufreq_kryo_probe, + .driver = { + .name = "qcom-cpufreq-kryo", + }, +}; + +static const struct of_device_id qcom_cpufreq_kryo_match_list[] __initconst = { + { .compatible = "qcom,apq8096", }, + { .compatible = "qcom,msm8996", }, +}; + +/* + * Since the driver depends on smem and nvmem drivers, which may + * return EPROBE_DEFER, all the real activity is done in the probe, + * which may be defered as well. The init here is only registering + * the driver and the platform device. + */ +static int __init qcom_cpufreq_kryo_init(void) +{ + struct device_node *np = of_find_node_by_path("/"); + const struct of_device_id *match; + int ret; + + if (!np) + return -ENODEV; + + match = of_match_node(qcom_cpufreq_kryo_match_list, np); + of_node_put(np); + if (!match) + return -ENODEV; + + ret = platform_driver_register(&qcom_cpufreq_kryo_driver); + if (unlikely(ret < 0)) + return ret; + + ret = PTR_ERR_OR_ZERO(platform_device_register_simple( + "qcom-cpufreq-kryo", -1, NULL, 0)); + if (0 == ret) + return 0; + + platform_driver_unregister(&qcom_cpufreq_kryo_driver); + return ret; +} +module_init(qcom_cpufreq_kryo_init); + +MODULE_DESCRIPTION("Qualcomm Technologies, Inc. Kryo CPUfreq driver"); +MODULE_LICENSE("GPL v2"); |