From: "Hector.Yuan" <hector.yuan@xxxxxxxxxxxx> Add MT6779 cpufreq HW support. Signed-off-by: Hector.Yuan <hector.yuan@xxxxxxxxxxxx> --- drivers/cpufreq/Kconfig.arm | 12 ++ drivers/cpufreq/Makefile | 1 + drivers/cpufreq/mediatek-cpufreq-hw.c | 305 +++++++++++++++++++++++++++++++++ 3 files changed, 318 insertions(+) create mode 100644 drivers/cpufreq/mediatek-cpufreq-hw.c diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm index c6cbfc8..8e58c12 100644 --- a/drivers/cpufreq/Kconfig.arm +++ b/drivers/cpufreq/Kconfig.arm @@ -121,6 +121,18 @@ 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 f6670c4..dc1f371 100644 --- a/drivers/cpufreq/Makefile +++ b/drivers/cpufreq/Makefile @@ -57,6 +57,7 @@ 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 0000000..86ce7f0 --- /dev/null +++ b/drivers/cpufreq/mediatek-cpufreq-hw.c @@ -0,0 +1,305 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2020 MediaTek Inc. + */ + +#include <linux/bitfield.h> +#include <linux/cpufreq.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of_address.h> +#include <linux/of_platform.h> +#include <linux/pm_opp.h> +#include <linux/slab.h> + +#define LUT_MAX_ENTRIES 32U +#define LUT_FREQ GENMASK(11, 0) +#define LUT_VOLT GENMASK(28, 12) +#define LUT_ROW_SIZE 0x4 + +enum { + REG_LUT_TABLE, + REG_ENABLE, + REG_PERF_STATE, + + REG_ARRAY_SIZE, +}; + +struct cpufreq_mtk { + struct cpufreq_frequency_table *table; + void __iomem *reg_bases[REG_ARRAY_SIZE]; + cpumask_t related_cpus; +}; + +static const u16 cpufreq_mtk_offsets[REG_ARRAY_SIZE] = { + [REG_LUT_TABLE] = 0x0, + [REG_ENABLE] = 0x84, + [REG_PERF_STATE] = 0x88, +}; + +static struct cpufreq_mtk *mtk_freq_domain_map[NR_CPUS]; + +static int mtk_cpufreq_hw_target_index(struct cpufreq_policy *policy, + unsigned int index) +{ + struct cpufreq_mtk *c = policy->driver_data; + + writel_relaxed(index, c->reg_bases[REG_PERF_STATE]); + arch_set_freq_scale(policy->related_cpus, + policy->freq_table[index].frequency, + policy->cpuinfo.max_freq); + + return 0; +} + +static unsigned int mtk_cpufreq_hw_get(unsigned int cpu) +{ + struct cpufreq_mtk *c; + struct cpufreq_policy *policy; + unsigned int index; + + policy = cpufreq_cpu_get_raw(cpu); + if (!policy) + return 0; + + c = policy->driver_data; + + index = readl_relaxed(c->reg_bases[REG_PERF_STATE]); + index = min(index, LUT_MAX_ENTRIES - 1); + + return policy->freq_table[index].frequency; +} + +static int mtk_cpufreq_hw_cpu_init(struct cpufreq_policy *policy) +{ + struct cpufreq_mtk *c; + struct device *cpu_dev; + int ret; + + cpu_dev = get_cpu_device(policy->cpu); + if (!cpu_dev) { + pr_err("%s: failed to get cpu%d device\n", __func__, + policy->cpu); + return -ENODEV; + } + + c = mtk_freq_domain_map[policy->cpu]; + if (!c) { + pr_err("No scaling support for CPU%d\n", policy->cpu); + return -ENODEV; + } + + cpumask_copy(policy->cpus, &c->related_cpus); + + ret = dev_pm_opp_get_opp_count(cpu_dev); + if (ret <= 0) + dev_err(cpu_dev, "OPP table is not ready\n"); + + policy->freq_table = c->table; + policy->driver_data = c; + + /* HW should be in enabled state to proceed now */ + writel_relaxed(0x1, c->reg_bases[REG_ENABLE]); + + return 0; +} + +static struct freq_attr *mtk_cpufreq_hw_attr[] = { + &cpufreq_freq_attr_scaling_available_freqs, + NULL +}; + +static struct cpufreq_driver cpufreq_mtk_hw_driver = { + .flags = CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK | + CPUFREQ_HAVE_GOVERNOR_PER_POLICY, + .verify = cpufreq_generic_frequency_table_verify, + .target_index = mtk_cpufreq_hw_target_index, + .get = mtk_cpufreq_hw_get, + .init = mtk_cpufreq_hw_cpu_init, + .name = "mtk-cpufreq-hw", + .attr = mtk_cpufreq_hw_attr, +}; + +static int mtk_cpufreq_hw_opp_create(struct platform_device *pdev, + struct cpufreq_mtk *c) +{ + struct device *dev = &pdev->dev; + void __iomem *base_table; + u32 data, i, freq, volt, prev_freq = 0; + unsigned long cpu; + + c->table = devm_kcalloc(dev, LUT_MAX_ENTRIES + 1, + sizeof(*c->table), GFP_KERNEL); + if (!c->table) + return -ENOMEM; + + base_table = c->reg_bases[REG_LUT_TABLE]; + + for (i = 0; i < LUT_MAX_ENTRIES; i++) { + data = readl_relaxed(base_table + (i * LUT_ROW_SIZE)); + freq = FIELD_GET(LUT_FREQ, data) * 1000; + volt = FIELD_GET(LUT_VOLT, data) * 10; + c->table[i].frequency = freq; + + dev_dbg(dev, "index=%d freq=%d\n", + i, c->table[i].frequency); + + if (freq == prev_freq) + break; + + prev_freq = freq; + + for_each_cpu(cpu, &c->related_cpus) + dev_pm_opp_add(get_cpu_device(cpu), freq, volt); + } + + c->table[i].frequency = CPUFREQ_TABLE_END; + + return 0; +} + +static int mtk_get_related_cpus(int index, struct cpumask *m) +{ + struct device_node *cpu_np; + struct of_phandle_args args; + int cpu, ret; + + for_each_possible_cpu(cpu) { + cpu_np = of_cpu_device_node_get(cpu); + if (!cpu_np) + continue; + + ret = of_parse_phandle_with_args(cpu_np, "mtk-freq-domain", + "#freq-domain-cells", 0, + &args); + of_node_put(cpu_np); + if (ret < 0) + continue; + + if (index == args.args[0]) + cpumask_set_cpu(cpu, m); + } + + return 0; +} + +static int mtk_cpu_resources_init(struct platform_device *pdev, + unsigned int cpu, int index) +{ + struct cpufreq_mtk *c; + struct resource *res; + struct device *dev = &pdev->dev; + const u16 *offsets; + int ret, i, cpu_r; + void __iomem *base; + + if (mtk_freq_domain_map[cpu]) + return 0; + + c = devm_kzalloc(dev, sizeof(*c), GFP_KERNEL); + if (!c) + return -ENOMEM; + + offsets = of_device_get_match_data(&pdev->dev); + if (!offsets) + return -EINVAL; + + res = platform_get_resource(pdev, IORESOURCE_MEM, index); + base = devm_ioremap_resource(dev, res); + if (IS_ERR(base)) + return PTR_ERR(base); + + for (i = REG_LUT_TABLE; i < REG_ARRAY_SIZE; i++) + c->reg_bases[i] = base + offsets[i]; + + ret = mtk_get_related_cpus(index, &c->related_cpus); + if (ret) { + dev_err(dev, "Domain-%d failed to get related CPUs\n", index); + return ret; + } + + ret = mtk_cpufreq_hw_opp_create(pdev, c); + if (ret) { + dev_err(dev, "Domain-%d failed to create OPP\n", index); + return ret; + } + + for_each_cpu(cpu_r, &c->related_cpus) + mtk_freq_domain_map[cpu_r] = c; + + return 0; +} + +static int mtk_resources_init(struct platform_device *pdev) +{ + struct device_node *cpu_np; + struct of_phandle_args args; + unsigned int cpu; + int ret; + + for_each_possible_cpu(cpu) { + cpu_np = of_cpu_device_node_get(cpu); + if (!cpu_np) { + dev_dbg(&pdev->dev, "Failed to get cpu %d device\n", + cpu); + continue; + } + + ret = of_parse_phandle_with_args(cpu_np, "mtk-freq-domain", + "#freq-domain-cells", 0, &args); + if (ret < 0) + return ret; + + ret = mtk_cpu_resources_init(pdev, cpu, args.args[0]); + if (ret) + return ret; + } + + return 0; +} + +static int mtk_cpufreq_hw_driver_probe(struct platform_device *pdev) +{ + int ret; + + /* Get the bases of cpufreq for domains */ + ret = mtk_resources_init(pdev); + if (ret) { + dev_err(&pdev->dev, "CPUFreq resource init failed\n"); + return ret; + } + + ret = cpufreq_register_driver(&cpufreq_mtk_hw_driver); + if (ret) { + dev_err(&pdev->dev, "CPUFreq HW driver failed to register\n"); + return ret; + } + + dev_dbg(&pdev->dev, "Mediatek CPUFreq HW driver initialized\n"); + of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev); + + return 0; +} + +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, + .driver = { + .name = "mtk-cpufreq-hw", + .of_match_table = mtk_cpufreq_hw_match, + }, +}; + +static int __init mtk_cpufreq_hw_init(void) +{ + return platform_driver_register(&mtk_cpufreq_hw_driver); +} +subsys_initcall(mtk_cpufreq_hw_init); + +MODULE_DESCRIPTION("mtk CPUFREQ HW Driver"); +MODULE_LICENSE("GPL v2"); -- 1.7.9.5