diff options
Diffstat (limited to 'drivers/cpufreq/imx-cpufreq-dt.c')
| -rw-r--r-- | drivers/cpufreq/imx-cpufreq-dt.c | 197 |
1 files changed, 197 insertions, 0 deletions
diff --git a/drivers/cpufreq/imx-cpufreq-dt.c b/drivers/cpufreq/imx-cpufreq-dt.c new file mode 100644 index 000000000..535867a7d --- /dev/null +++ b/drivers/cpufreq/imx-cpufreq-dt.c @@ -0,0 +1,197 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2019 NXP + */ + +#include <linux/clk.h> +#include <linux/cpu.h> +#include <linux/cpufreq.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/regulator/consumer.h> +#include <linux/slab.h> + +#include "cpufreq-dt.h" + +#define OCOTP_CFG3_SPEED_GRADE_SHIFT 8 +#define OCOTP_CFG3_SPEED_GRADE_MASK (0x3 << 8) +#define IMX8MN_OCOTP_CFG3_SPEED_GRADE_MASK (0xf << 8) +#define OCOTP_CFG3_MKT_SEGMENT_SHIFT 6 +#define OCOTP_CFG3_MKT_SEGMENT_MASK (0x3 << 6) +#define IMX8MP_OCOTP_CFG3_MKT_SEGMENT_SHIFT 5 +#define IMX8MP_OCOTP_CFG3_MKT_SEGMENT_MASK (0x3 << 5) + +#define IMX7ULP_MAX_RUN_FREQ 528000 + +/* cpufreq-dt device registered by imx-cpufreq-dt */ +static struct platform_device *cpufreq_dt_pdev; +static struct device *cpu_dev; +static int cpufreq_opp_token; + +enum IMX7ULP_CPUFREQ_CLKS { + ARM, + CORE, + SCS_SEL, + HSRUN_CORE, + HSRUN_SCS_SEL, + FIRC, +}; + +static struct clk_bulk_data imx7ulp_clks[] = { + { .id = "arm" }, + { .id = "core" }, + { .id = "scs_sel" }, + { .id = "hsrun_core" }, + { .id = "hsrun_scs_sel" }, + { .id = "firc" }, +}; + +static unsigned int imx7ulp_get_intermediate(struct cpufreq_policy *policy, + unsigned int index) +{ + return clk_get_rate(imx7ulp_clks[FIRC].clk); +} + +static int imx7ulp_target_intermediate(struct cpufreq_policy *policy, + unsigned int index) +{ + unsigned int newfreq = policy->freq_table[index].frequency; + + clk_set_parent(imx7ulp_clks[SCS_SEL].clk, imx7ulp_clks[FIRC].clk); + clk_set_parent(imx7ulp_clks[HSRUN_SCS_SEL].clk, imx7ulp_clks[FIRC].clk); + + if (newfreq > IMX7ULP_MAX_RUN_FREQ) + clk_set_parent(imx7ulp_clks[ARM].clk, + imx7ulp_clks[HSRUN_CORE].clk); + else + clk_set_parent(imx7ulp_clks[ARM].clk, imx7ulp_clks[CORE].clk); + + return 0; +} + +static struct cpufreq_dt_platform_data imx7ulp_data = { + .target_intermediate = imx7ulp_target_intermediate, + .get_intermediate = imx7ulp_get_intermediate, +}; + +static int imx_cpufreq_dt_probe(struct platform_device *pdev) +{ + struct platform_device *dt_pdev; + u32 cell_value, supported_hw[2]; + int speed_grade, mkt_segment; + int ret; + + cpu_dev = get_cpu_device(0); + + if (!of_property_present(cpu_dev->of_node, "cpu-supply")) + return -ENODEV; + + if (of_machine_is_compatible("fsl,imx7ulp")) { + ret = clk_bulk_get(cpu_dev, ARRAY_SIZE(imx7ulp_clks), + imx7ulp_clks); + if (ret) + return ret; + + dt_pdev = platform_device_register_data(NULL, "cpufreq-dt", + -1, &imx7ulp_data, + sizeof(imx7ulp_data)); + if (IS_ERR(dt_pdev)) { + clk_bulk_put(ARRAY_SIZE(imx7ulp_clks), imx7ulp_clks); + ret = PTR_ERR(dt_pdev); + dev_err(&pdev->dev, "Failed to register cpufreq-dt: %d\n", ret); + return ret; + } + + cpufreq_dt_pdev = dt_pdev; + + return 0; + } + + ret = nvmem_cell_read_u32(cpu_dev, "speed_grade", &cell_value); + if (ret) + return ret; + + if (of_machine_is_compatible("fsl,imx8mn") || + of_machine_is_compatible("fsl,imx8mp")) + speed_grade = (cell_value & IMX8MN_OCOTP_CFG3_SPEED_GRADE_MASK) + >> OCOTP_CFG3_SPEED_GRADE_SHIFT; + else + speed_grade = (cell_value & OCOTP_CFG3_SPEED_GRADE_MASK) + >> OCOTP_CFG3_SPEED_GRADE_SHIFT; + + if (of_machine_is_compatible("fsl,imx8mp")) + mkt_segment = (cell_value & IMX8MP_OCOTP_CFG3_MKT_SEGMENT_MASK) + >> IMX8MP_OCOTP_CFG3_MKT_SEGMENT_SHIFT; + else + mkt_segment = (cell_value & OCOTP_CFG3_MKT_SEGMENT_MASK) + >> OCOTP_CFG3_MKT_SEGMENT_SHIFT; + + /* + * Early samples without fuses written report "0 0" which may NOT + * match any OPP defined in DT. So clamp to minimum OPP defined in + * DT to avoid warning for "no OPPs". + * + * Applies to i.MX8M series SoCs. + */ + if (mkt_segment == 0 && speed_grade == 0) { + if (of_machine_is_compatible("fsl,imx8mm") || + of_machine_is_compatible("fsl,imx8mq")) + speed_grade = 1; + if (of_machine_is_compatible("fsl,imx8mn") || + of_machine_is_compatible("fsl,imx8mp")) + speed_grade = 0xb; + } + + supported_hw[0] = BIT(speed_grade); + supported_hw[1] = BIT(mkt_segment); + dev_info(&pdev->dev, "cpu speed grade %d mkt segment %d supported-hw %#x %#x\n", + speed_grade, mkt_segment, supported_hw[0], supported_hw[1]); + + cpufreq_opp_token = dev_pm_opp_set_supported_hw(cpu_dev, supported_hw, 2); + if (cpufreq_opp_token < 0) { + ret = cpufreq_opp_token; + dev_err(&pdev->dev, "Failed to set supported opp: %d\n", ret); + return ret; + } + + cpufreq_dt_pdev = platform_device_register_data( + &pdev->dev, "cpufreq-dt", -1, NULL, 0); + if (IS_ERR(cpufreq_dt_pdev)) { + dev_pm_opp_put_supported_hw(cpufreq_opp_token); + ret = PTR_ERR(cpufreq_dt_pdev); + dev_err(&pdev->dev, "Failed to register cpufreq-dt: %d\n", ret); + return ret; + } + + return 0; +} + +static int imx_cpufreq_dt_remove(struct platform_device *pdev) +{ + platform_device_unregister(cpufreq_dt_pdev); + if (!of_machine_is_compatible("fsl,imx7ulp")) + dev_pm_opp_put_supported_hw(cpufreq_opp_token); + else + clk_bulk_put(ARRAY_SIZE(imx7ulp_clks), imx7ulp_clks); + + return 0; +} + +static struct platform_driver imx_cpufreq_dt_driver = { + .probe = imx_cpufreq_dt_probe, + .remove = imx_cpufreq_dt_remove, + .driver = { + .name = "imx-cpufreq-dt", + }, +}; +module_platform_driver(imx_cpufreq_dt_driver); + +MODULE_ALIAS("platform:imx-cpufreq-dt"); +MODULE_DESCRIPTION("Freescale i.MX cpufreq speed grading driver"); +MODULE_LICENSE("GPL v2"); |