| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * Copyright (c) 2020 MediaTek Inc. |
| */ |
| |
| #include <linux/bitfield.h> |
| #include <linux/cpufreq.h> |
| #include <linux/energy_model.h> |
| #include <linux/init.h> |
| #include <linux/iopoll.h> |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/of_address.h> |
| #include <linux/of_platform.h> |
| #include <linux/slab.h> |
| |
| #define LUT_MAX_ENTRIES 32U |
| #define LUT_FREQ GENMASK(11, 0) |
| #define LUT_ROW_SIZE 0x4 |
| #define CPUFREQ_HW_STATUS BIT(0) |
| #define SVS_HW_STATUS BIT(1) |
| #define POLL_USEC 1000 |
| #define TIMEOUT_USEC 300000 |
| |
| enum { |
| REG_FREQ_LUT_TABLE, |
| REG_FREQ_ENABLE, |
| REG_FREQ_PERF_STATE, |
| REG_FREQ_HW_STATE, |
| REG_EM_POWER_TBL, |
| REG_FREQ_LATENCY, |
| |
| REG_ARRAY_SIZE, |
| }; |
| |
| struct mtk_cpufreq_data { |
| struct cpufreq_frequency_table *table; |
| void __iomem *reg_bases[REG_ARRAY_SIZE]; |
| struct resource *res; |
| void __iomem *base; |
| int nr_opp; |
| }; |
| |
| static const u16 cpufreq_mtk_offsets[REG_ARRAY_SIZE] = { |
| [REG_FREQ_LUT_TABLE] = 0x0, |
| [REG_FREQ_ENABLE] = 0x84, |
| [REG_FREQ_PERF_STATE] = 0x88, |
| [REG_FREQ_HW_STATE] = 0x8c, |
| [REG_EM_POWER_TBL] = 0x90, |
| [REG_FREQ_LATENCY] = 0x110, |
| }; |
| |
| static int __maybe_unused |
| mtk_cpufreq_get_cpu_power(unsigned long *mW, |
| unsigned long *KHz, struct device *cpu_dev) |
| { |
| struct mtk_cpufreq_data *data; |
| struct cpufreq_policy *policy; |
| int i; |
| |
| policy = cpufreq_cpu_get_raw(cpu_dev->id); |
| if (!policy) |
| return 0; |
| |
| data = policy->driver_data; |
| |
| for (i = 0; i < data->nr_opp; i++) { |
| if (data->table[i].frequency < *KHz) |
| break; |
| } |
| i--; |
| |
| *KHz = data->table[i].frequency; |
| *mW = readl_relaxed(data->reg_bases[REG_EM_POWER_TBL] + |
| i * LUT_ROW_SIZE) / 1000; |
| |
| return 0; |
| } |
| |
| static int mtk_cpufreq_hw_target_index(struct cpufreq_policy *policy, |
| unsigned int index) |
| { |
| struct mtk_cpufreq_data *data = policy->driver_data; |
| |
| writel_relaxed(index, data->reg_bases[REG_FREQ_PERF_STATE]); |
| |
| return 0; |
| } |
| |
| static unsigned int mtk_cpufreq_hw_get(unsigned int cpu) |
| { |
| struct mtk_cpufreq_data *data; |
| struct cpufreq_policy *policy; |
| unsigned int index; |
| |
| policy = cpufreq_cpu_get_raw(cpu); |
| if (!policy) |
| return 0; |
| |
| data = policy->driver_data; |
| |
| index = readl_relaxed(data->reg_bases[REG_FREQ_PERF_STATE]); |
| index = min(index, LUT_MAX_ENTRIES - 1); |
| |
| return data->table[index].frequency; |
| } |
| |
| static unsigned int mtk_cpufreq_hw_fast_switch(struct cpufreq_policy *policy, |
| unsigned int target_freq) |
| { |
| struct mtk_cpufreq_data *data = policy->driver_data; |
| unsigned int index; |
| |
| index = cpufreq_table_find_index_dl(policy, target_freq, false); |
| |
| writel_relaxed(index, data->reg_bases[REG_FREQ_PERF_STATE]); |
| |
| return policy->freq_table[index].frequency; |
| } |
| |
| static int mtk_cpu_create_freq_table(struct platform_device *pdev, |
| struct mtk_cpufreq_data *data) |
| { |
| struct device *dev = &pdev->dev; |
| u32 temp, i, freq, prev_freq = 0; |
| void __iomem *base_table; |
| |
| data->table = devm_kcalloc(dev, LUT_MAX_ENTRIES + 1, |
| sizeof(*data->table), GFP_KERNEL); |
| if (!data->table) |
| return -ENOMEM; |
| |
| base_table = data->reg_bases[REG_FREQ_LUT_TABLE]; |
| |
| for (i = 0; i < LUT_MAX_ENTRIES; i++) { |
| temp = readl_relaxed(base_table + (i * LUT_ROW_SIZE)); |
| freq = FIELD_GET(LUT_FREQ, temp) * 1000; |
| |
| if (freq == prev_freq) |
| break; |
| |
| data->table[i].frequency = freq; |
| |
| dev_dbg(dev, "index=%d freq=%d\n", i, data->table[i].frequency); |
| |
| prev_freq = freq; |
| } |
| |
| data->table[i].frequency = CPUFREQ_TABLE_END; |
| data->nr_opp = i; |
| |
| return 0; |
| } |
| |
| static int mtk_cpu_resources_init(struct platform_device *pdev, |
| struct cpufreq_policy *policy, |
| const u16 *offsets) |
| { |
| struct mtk_cpufreq_data *data; |
| struct device *dev = &pdev->dev; |
| struct resource *res; |
| void __iomem *base; |
| int ret, i; |
| int index; |
| |
| data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); |
| if (!data) |
| return -ENOMEM; |
| |
| index = of_perf_domain_get_sharing_cpumask(policy->cpu, "performance-domains", |
| "#performance-domain-cells", |
| policy->cpus); |
| if (index < 0) |
| return index; |
| |
| res = platform_get_resource(pdev, IORESOURCE_MEM, index); |
| if (!res) { |
| dev_err(dev, "failed to get mem resource %d\n", index); |
| return -ENODEV; |
| } |
| |
| if (!request_mem_region(res->start, resource_size(res), res->name)) { |
| dev_err(dev, "failed to request resource %pR\n", res); |
| return -EBUSY; |
| } |
| |
| base = ioremap(res->start, resource_size(res)); |
| if (!base) { |
| dev_err(dev, "failed to map resource %pR\n", res); |
| ret = -ENOMEM; |
| goto release_region; |
| } |
| |
| data->base = base; |
| data->res = res; |
| |
| for (i = REG_FREQ_LUT_TABLE; i < REG_ARRAY_SIZE; i++) |
| data->reg_bases[i] = base + offsets[i]; |
| |
| ret = mtk_cpu_create_freq_table(pdev, data); |
| if (ret) { |
| dev_info(dev, "Domain-%d failed to create freq table\n", index); |
| return ret; |
| } |
| |
| policy->freq_table = data->table; |
| policy->driver_data = data; |
| |
| return 0; |
| release_region: |
| release_mem_region(res->start, resource_size(res)); |
| return ret; |
| } |
| |
| static int mtk_cpufreq_hw_cpu_init(struct cpufreq_policy *policy) |
| { |
| struct platform_device *pdev = cpufreq_get_driver_data(); |
| int sig, pwr_hw = CPUFREQ_HW_STATUS | SVS_HW_STATUS; |
| struct mtk_cpufreq_data *data; |
| unsigned int latency; |
| int ret; |
| |
| /* Get the bases of cpufreq for domains */ |
| ret = mtk_cpu_resources_init(pdev, policy, platform_get_drvdata(pdev)); |
| if (ret) { |
| dev_info(&pdev->dev, "CPUFreq resource init failed\n"); |
| return ret; |
| } |
| |
| data = policy->driver_data; |
| |
| latency = readl_relaxed(data->reg_bases[REG_FREQ_LATENCY]) * 1000; |
| if (!latency) |
| latency = CPUFREQ_ETERNAL; |
| |
| policy->cpuinfo.transition_latency = latency; |
| policy->fast_switch_possible = true; |
| |
| /* HW should be in enabled state to proceed now */ |
| writel_relaxed(0x1, data->reg_bases[REG_FREQ_ENABLE]); |
| if (readl_poll_timeout(data->reg_bases[REG_FREQ_HW_STATE], sig, |
| (sig & pwr_hw) == pwr_hw, POLL_USEC, |
| TIMEOUT_USEC)) { |
| if (!(sig & CPUFREQ_HW_STATUS)) { |
| pr_info("cpufreq hardware of CPU%d is not enabled\n", |
| policy->cpu); |
| return -ENODEV; |
| } |
| |
| pr_info("SVS of CPU%d is not enabled\n", policy->cpu); |
| } |
| |
| return 0; |
| } |
| |
| static int mtk_cpufreq_hw_cpu_exit(struct cpufreq_policy *policy) |
| { |
| struct mtk_cpufreq_data *data = policy->driver_data; |
| struct resource *res = data->res; |
| void __iomem *base = data->base; |
| |
| /* HW should be in paused state now */ |
| writel_relaxed(0x0, data->reg_bases[REG_FREQ_ENABLE]); |
| iounmap(base); |
| release_mem_region(res->start, resource_size(res)); |
| |
| return 0; |
| } |
| |
| static void mtk_cpufreq_register_em(struct cpufreq_policy *policy) |
| { |
| struct em_data_callback em_cb = EM_DATA_CB(mtk_cpufreq_get_cpu_power); |
| struct mtk_cpufreq_data *data = policy->driver_data; |
| |
| em_dev_register_perf_domain(get_cpu_device(policy->cpu), data->nr_opp, |
| &em_cb, policy->cpus, true); |
| } |
| |
| static struct cpufreq_driver cpufreq_mtk_hw_driver = { |
| .flags = CPUFREQ_NEED_INITIAL_FREQ_CHECK | |
| CPUFREQ_HAVE_GOVERNOR_PER_POLICY | |
| CPUFREQ_IS_COOLING_DEV, |
| .verify = cpufreq_generic_frequency_table_verify, |
| .target_index = mtk_cpufreq_hw_target_index, |
| .get = mtk_cpufreq_hw_get, |
| .init = mtk_cpufreq_hw_cpu_init, |
| .exit = mtk_cpufreq_hw_cpu_exit, |
| .register_em = mtk_cpufreq_register_em, |
| .fast_switch = mtk_cpufreq_hw_fast_switch, |
| .name = "mtk-cpufreq-hw", |
| .attr = cpufreq_generic_attr, |
| }; |
| |
| static int mtk_cpufreq_hw_driver_probe(struct platform_device *pdev) |
| { |
| const void *data; |
| int ret; |
| |
| data = of_device_get_match_data(&pdev->dev); |
| if (!data) |
| return -EINVAL; |
| |
| platform_set_drvdata(pdev, (void *) data); |
| cpufreq_mtk_hw_driver.driver_data = pdev; |
| |
| ret = cpufreq_register_driver(&cpufreq_mtk_hw_driver); |
| if (ret) |
| dev_err(&pdev->dev, "CPUFreq HW driver failed to register\n"); |
| |
| return ret; |
| } |
| |
| static int mtk_cpufreq_hw_driver_remove(struct platform_device *pdev) |
| { |
| return cpufreq_unregister_driver(&cpufreq_mtk_hw_driver); |
| } |
| |
| static const struct of_device_id mtk_cpufreq_hw_match[] = { |
| { .compatible = "mediatek,cpufreq-hw", .data = &cpufreq_mtk_offsets }, |
| {} |
| }; |
| |
| static struct platform_driver mtk_cpufreq_hw_driver = { |
| .probe = mtk_cpufreq_hw_driver_probe, |
| .remove = mtk_cpufreq_hw_driver_remove, |
| .driver = { |
| .name = "mtk-cpufreq-hw", |
| .of_match_table = mtk_cpufreq_hw_match, |
| }, |
| }; |
| module_platform_driver(mtk_cpufreq_hw_driver); |
| |
| MODULE_AUTHOR("Hector Yuan <hector.yuan@mediatek.com>"); |
| MODULE_DESCRIPTION("Mediatek cpufreq-hw driver"); |
| MODULE_LICENSE("GPL v2"); |