From 4855e26bcf4d28956f3e33231b961610a0d4a72d Mon Sep 17 00:00:00 2001 From: "Hector.Yuan" Date: Fri, 3 Sep 2021 16:39:24 +0800 Subject: cpufreq: mediatek-hw: Add support for CPUFREQ HW Introduce cpufreq HW driver which can support CPU frequency adjust in MT6779 platform. Signed-off-by: Hector.Yuan [ Viresh: Massaged the patch and cleaned some stuff. ] Signed-off-by: Viresh Kumar --- drivers/cpufreq/Kconfig.arm | 12 ++ drivers/cpufreq/Makefile | 1 + drivers/cpufreq/mediatek-cpufreq-hw.c | 308 ++++++++++++++++++++++++++++++++++ 3 files changed, 321 insertions(+) create mode 100644 drivers/cpufreq/mediatek-cpufreq-hw.c diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm index a5c5f70acfc9..954749afb5fe 100644 --- a/drivers/cpufreq/Kconfig.arm +++ b/drivers/cpufreq/Kconfig.arm @@ -133,6 +133,18 @@ config ARM_MEDIATEK_CPUFREQ help This adds the CPUFreq driver support for MediaTek SoCs. +config ARM_MEDIATEK_CPUFREQ_HW + tristate "MediaTek CPUFreq HW driver" + depends on ARCH_MEDIATEK || COMPILE_TEST + default m + help + Support for the CPUFreq HW driver. + Some MediaTek chipsets have a HW engine to offload the steps + necessary for changing the frequency of the CPUs. Firmware loaded + in this engine exposes a programming interface to the OS. + The driver implements the cpufreq interface for this HW engine. + Say Y if you want to support CPUFreq HW. + config ARM_OMAP2PLUS_CPUFREQ bool "TI OMAP2+" depends on ARCH_OMAP2PLUS diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile index 27d3bd7ea9d4..48ee5859030c 100644 --- a/drivers/cpufreq/Makefile +++ b/drivers/cpufreq/Makefile @@ -56,6 +56,7 @@ obj-$(CONFIG_ARM_IMX6Q_CPUFREQ) += imx6q-cpufreq.o obj-$(CONFIG_ARM_IMX_CPUFREQ_DT) += imx-cpufreq-dt.o obj-$(CONFIG_ARM_KIRKWOOD_CPUFREQ) += kirkwood-cpufreq.o obj-$(CONFIG_ARM_MEDIATEK_CPUFREQ) += mediatek-cpufreq.o +obj-$(CONFIG_ARM_MEDIATEK_CPUFREQ_HW) += mediatek-cpufreq-hw.o obj-$(CONFIG_MACH_MVEBU_V7) += mvebu-cpufreq.o obj-$(CONFIG_ARM_OMAP2PLUS_CPUFREQ) += omap-cpufreq.o obj-$(CONFIG_ARM_PXA2xx_CPUFREQ) += pxa2xx-cpufreq.o diff --git a/drivers/cpufreq/mediatek-cpufreq-hw.c b/drivers/cpufreq/mediatek-cpufreq-hw.c new file mode 100644 index 000000000000..0cf18dd46b92 --- /dev/null +++ b/drivers/cpufreq/mediatek-cpufreq-hw.c @@ -0,0 +1,308 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2020 MediaTek Inc. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#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]; + 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); + + 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; + 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; + + base = devm_platform_ioremap_resource(pdev, index); + if (IS_ERR(base)) + return PTR_ERR(base); + + 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; +} + +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; + + /* HW should be in paused state now */ + writel_relaxed(0x0, data->reg_bases[REG_FREQ_ENABLE]); + + 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 "); +MODULE_DESCRIPTION("Mediatek cpufreq-hw driver"); +MODULE_LICENSE("GPL v2"); -- cgit v1.2.3