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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/cpufreq/imx6q-cpufreq.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/cpufreq/imx6q-cpufreq.c')
-rw-r--r-- | drivers/cpufreq/imx6q-cpufreq.c | 549 |
1 files changed, 549 insertions, 0 deletions
diff --git a/drivers/cpufreq/imx6q-cpufreq.c b/drivers/cpufreq/imx6q-cpufreq.c new file mode 100644 index 000000000..39b0362a3 --- /dev/null +++ b/drivers/cpufreq/imx6q-cpufreq.c @@ -0,0 +1,549 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2013 Freescale Semiconductor, Inc. + */ + +#include <linux/clk.h> +#include <linux/cpu.h> +#include <linux/cpufreq.h> +#include <linux/err.h> +#include <linux/module.h> +#include <linux/nvmem-consumer.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/pm_opp.h> +#include <linux/platform_device.h> +#include <linux/regulator/consumer.h> + +#define PU_SOC_VOLTAGE_NORMAL 1250000 +#define PU_SOC_VOLTAGE_HIGH 1275000 +#define FREQ_1P2_GHZ 1200000000 + +static struct regulator *arm_reg; +static struct regulator *pu_reg; +static struct regulator *soc_reg; + +enum IMX6_CPUFREQ_CLKS { + ARM, + PLL1_SYS, + STEP, + PLL1_SW, + PLL2_PFD2_396M, + /* MX6UL requires two more clks */ + PLL2_BUS, + SECONDARY_SEL, +}; +#define IMX6Q_CPUFREQ_CLK_NUM 5 +#define IMX6UL_CPUFREQ_CLK_NUM 7 + +static int num_clks; +static struct clk_bulk_data clks[] = { + { .id = "arm" }, + { .id = "pll1_sys" }, + { .id = "step" }, + { .id = "pll1_sw" }, + { .id = "pll2_pfd2_396m" }, + { .id = "pll2_bus" }, + { .id = "secondary_sel" }, +}; + +static struct device *cpu_dev; +static struct cpufreq_frequency_table *freq_table; +static unsigned int max_freq; +static unsigned int transition_latency; + +static u32 *imx6_soc_volt; +static u32 soc_opp_count; + +static int imx6q_set_target(struct cpufreq_policy *policy, unsigned int index) +{ + struct dev_pm_opp *opp; + unsigned long freq_hz, volt, volt_old; + unsigned int old_freq, new_freq; + bool pll1_sys_temp_enabled = false; + int ret; + + new_freq = freq_table[index].frequency; + freq_hz = new_freq * 1000; + old_freq = clk_get_rate(clks[ARM].clk) / 1000; + + opp = dev_pm_opp_find_freq_ceil(cpu_dev, &freq_hz); + if (IS_ERR(opp)) { + dev_err(cpu_dev, "failed to find OPP for %ld\n", freq_hz); + return PTR_ERR(opp); + } + + volt = dev_pm_opp_get_voltage(opp); + dev_pm_opp_put(opp); + + volt_old = regulator_get_voltage(arm_reg); + + dev_dbg(cpu_dev, "%u MHz, %ld mV --> %u MHz, %ld mV\n", + old_freq / 1000, volt_old / 1000, + new_freq / 1000, volt / 1000); + + /* scaling up? scale voltage before frequency */ + if (new_freq > old_freq) { + if (!IS_ERR(pu_reg)) { + ret = regulator_set_voltage_tol(pu_reg, imx6_soc_volt[index], 0); + if (ret) { + dev_err(cpu_dev, "failed to scale vddpu up: %d\n", ret); + return ret; + } + } + ret = regulator_set_voltage_tol(soc_reg, imx6_soc_volt[index], 0); + if (ret) { + dev_err(cpu_dev, "failed to scale vddsoc up: %d\n", ret); + return ret; + } + ret = regulator_set_voltage_tol(arm_reg, volt, 0); + if (ret) { + dev_err(cpu_dev, + "failed to scale vddarm up: %d\n", ret); + return ret; + } + } + + /* + * The setpoints are selected per PLL/PDF frequencies, so we need to + * reprogram PLL for frequency scaling. The procedure of reprogramming + * PLL1 is as below. + * For i.MX6UL, it has a secondary clk mux, the cpu frequency change + * flow is slightly different from other i.MX6 OSC. + * The cpu frequeny change flow for i.MX6(except i.MX6UL) is as below: + * - Enable pll2_pfd2_396m_clk and reparent pll1_sw_clk to it + * - Reprogram pll1_sys_clk and reparent pll1_sw_clk back to it + * - Disable pll2_pfd2_396m_clk + */ + if (of_machine_is_compatible("fsl,imx6ul") || + of_machine_is_compatible("fsl,imx6ull")) { + /* + * When changing pll1_sw_clk's parent to pll1_sys_clk, + * CPU may run at higher than 528MHz, this will lead to + * the system unstable if the voltage is lower than the + * voltage of 528MHz, so lower the CPU frequency to one + * half before changing CPU frequency. + */ + clk_set_rate(clks[ARM].clk, (old_freq >> 1) * 1000); + clk_set_parent(clks[PLL1_SW].clk, clks[PLL1_SYS].clk); + if (freq_hz > clk_get_rate(clks[PLL2_PFD2_396M].clk)) + clk_set_parent(clks[SECONDARY_SEL].clk, + clks[PLL2_BUS].clk); + else + clk_set_parent(clks[SECONDARY_SEL].clk, + clks[PLL2_PFD2_396M].clk); + clk_set_parent(clks[STEP].clk, clks[SECONDARY_SEL].clk); + clk_set_parent(clks[PLL1_SW].clk, clks[STEP].clk); + if (freq_hz > clk_get_rate(clks[PLL2_BUS].clk)) { + clk_set_rate(clks[PLL1_SYS].clk, new_freq * 1000); + clk_set_parent(clks[PLL1_SW].clk, clks[PLL1_SYS].clk); + } + } else { + clk_set_parent(clks[STEP].clk, clks[PLL2_PFD2_396M].clk); + clk_set_parent(clks[PLL1_SW].clk, clks[STEP].clk); + if (freq_hz > clk_get_rate(clks[PLL2_PFD2_396M].clk)) { + clk_set_rate(clks[PLL1_SYS].clk, new_freq * 1000); + clk_set_parent(clks[PLL1_SW].clk, clks[PLL1_SYS].clk); + } else { + /* pll1_sys needs to be enabled for divider rate change to work. */ + pll1_sys_temp_enabled = true; + clk_prepare_enable(clks[PLL1_SYS].clk); + } + } + + /* Ensure the arm clock divider is what we expect */ + ret = clk_set_rate(clks[ARM].clk, new_freq * 1000); + if (ret) { + int ret1; + + dev_err(cpu_dev, "failed to set clock rate: %d\n", ret); + ret1 = regulator_set_voltage_tol(arm_reg, volt_old, 0); + if (ret1) + dev_warn(cpu_dev, + "failed to restore vddarm voltage: %d\n", ret1); + return ret; + } + + /* PLL1 is only needed until after ARM-PODF is set. */ + if (pll1_sys_temp_enabled) + clk_disable_unprepare(clks[PLL1_SYS].clk); + + /* scaling down? scale voltage after frequency */ + if (new_freq < old_freq) { + ret = regulator_set_voltage_tol(arm_reg, volt, 0); + if (ret) + dev_warn(cpu_dev, + "failed to scale vddarm down: %d\n", ret); + ret = regulator_set_voltage_tol(soc_reg, imx6_soc_volt[index], 0); + if (ret) + dev_warn(cpu_dev, "failed to scale vddsoc down: %d\n", ret); + if (!IS_ERR(pu_reg)) { + ret = regulator_set_voltage_tol(pu_reg, imx6_soc_volt[index], 0); + if (ret) + dev_warn(cpu_dev, "failed to scale vddpu down: %d\n", ret); + } + } + + return 0; +} + +static int imx6q_cpufreq_init(struct cpufreq_policy *policy) +{ + policy->clk = clks[ARM].clk; + cpufreq_generic_init(policy, freq_table, transition_latency); + policy->suspend_freq = max_freq; + + return 0; +} + +static struct cpufreq_driver imx6q_cpufreq_driver = { + .flags = CPUFREQ_NEED_INITIAL_FREQ_CHECK | + CPUFREQ_IS_COOLING_DEV, + .verify = cpufreq_generic_frequency_table_verify, + .target_index = imx6q_set_target, + .get = cpufreq_generic_get, + .init = imx6q_cpufreq_init, + .register_em = cpufreq_register_em_with_opp, + .name = "imx6q-cpufreq", + .attr = cpufreq_generic_attr, + .suspend = cpufreq_generic_suspend, +}; + +static void imx6x_disable_freq_in_opp(struct device *dev, unsigned long freq) +{ + int ret = dev_pm_opp_disable(dev, freq); + + if (ret < 0 && ret != -ENODEV) + dev_warn(dev, "failed to disable %ldMHz OPP\n", freq / 1000000); +} + +#define OCOTP_CFG3 0x440 +#define OCOTP_CFG3_SPEED_SHIFT 16 +#define OCOTP_CFG3_SPEED_1P2GHZ 0x3 +#define OCOTP_CFG3_SPEED_996MHZ 0x2 +#define OCOTP_CFG3_SPEED_852MHZ 0x1 + +static int imx6q_opp_check_speed_grading(struct device *dev) +{ + struct device_node *np; + void __iomem *base; + u32 val; + int ret; + + if (of_property_present(dev->of_node, "nvmem-cells")) { + ret = nvmem_cell_read_u32(dev, "speed_grade", &val); + if (ret) + return ret; + } else { + np = of_find_compatible_node(NULL, NULL, "fsl,imx6q-ocotp"); + if (!np) + return -ENOENT; + + base = of_iomap(np, 0); + of_node_put(np); + if (!base) { + dev_err(dev, "failed to map ocotp\n"); + return -EFAULT; + } + + /* + * SPEED_GRADING[1:0] defines the max speed of ARM: + * 2b'11: 1200000000Hz; + * 2b'10: 996000000Hz; + * 2b'01: 852000000Hz; -- i.MX6Q Only, exclusive with 996MHz. + * 2b'00: 792000000Hz; + * We need to set the max speed of ARM according to fuse map. + */ + val = readl_relaxed(base + OCOTP_CFG3); + iounmap(base); + } + + val >>= OCOTP_CFG3_SPEED_SHIFT; + val &= 0x3; + + if (val < OCOTP_CFG3_SPEED_996MHZ) + imx6x_disable_freq_in_opp(dev, 996000000); + + if (of_machine_is_compatible("fsl,imx6q") || + of_machine_is_compatible("fsl,imx6qp")) { + if (val != OCOTP_CFG3_SPEED_852MHZ) + imx6x_disable_freq_in_opp(dev, 852000000); + + if (val != OCOTP_CFG3_SPEED_1P2GHZ) + imx6x_disable_freq_in_opp(dev, 1200000000); + } + + return 0; +} + +#define OCOTP_CFG3_6UL_SPEED_696MHZ 0x2 +#define OCOTP_CFG3_6ULL_SPEED_792MHZ 0x2 +#define OCOTP_CFG3_6ULL_SPEED_900MHZ 0x3 + +static int imx6ul_opp_check_speed_grading(struct device *dev) +{ + u32 val; + int ret = 0; + + if (of_property_present(dev->of_node, "nvmem-cells")) { + ret = nvmem_cell_read_u32(dev, "speed_grade", &val); + if (ret) + return ret; + } else { + struct device_node *np; + void __iomem *base; + + np = of_find_compatible_node(NULL, NULL, "fsl,imx6ul-ocotp"); + if (!np) + np = of_find_compatible_node(NULL, NULL, + "fsl,imx6ull-ocotp"); + if (!np) + return -ENOENT; + + base = of_iomap(np, 0); + of_node_put(np); + if (!base) { + dev_err(dev, "failed to map ocotp\n"); + return -EFAULT; + } + + val = readl_relaxed(base + OCOTP_CFG3); + iounmap(base); + } + + /* + * Speed GRADING[1:0] defines the max speed of ARM: + * 2b'00: Reserved; + * 2b'01: 528000000Hz; + * 2b'10: 696000000Hz on i.MX6UL, 792000000Hz on i.MX6ULL; + * 2b'11: 900000000Hz on i.MX6ULL only; + * We need to set the max speed of ARM according to fuse map. + */ + val >>= OCOTP_CFG3_SPEED_SHIFT; + val &= 0x3; + + if (of_machine_is_compatible("fsl,imx6ul")) + if (val != OCOTP_CFG3_6UL_SPEED_696MHZ) + imx6x_disable_freq_in_opp(dev, 696000000); + + if (of_machine_is_compatible("fsl,imx6ull")) { + if (val < OCOTP_CFG3_6ULL_SPEED_792MHZ) + imx6x_disable_freq_in_opp(dev, 792000000); + + if (val != OCOTP_CFG3_6ULL_SPEED_900MHZ) + imx6x_disable_freq_in_opp(dev, 900000000); + } + + return ret; +} + +static int imx6q_cpufreq_probe(struct platform_device *pdev) +{ + struct device_node *np; + struct dev_pm_opp *opp; + unsigned long min_volt, max_volt; + int num, ret; + const struct property *prop; + const __be32 *val; + u32 nr, i, j; + + cpu_dev = get_cpu_device(0); + if (!cpu_dev) { + pr_err("failed to get cpu0 device\n"); + return -ENODEV; + } + + np = of_node_get(cpu_dev->of_node); + if (!np) { + dev_err(cpu_dev, "failed to find cpu0 node\n"); + return -ENOENT; + } + + if (of_machine_is_compatible("fsl,imx6ul") || + of_machine_is_compatible("fsl,imx6ull")) + num_clks = IMX6UL_CPUFREQ_CLK_NUM; + else + num_clks = IMX6Q_CPUFREQ_CLK_NUM; + + ret = clk_bulk_get(cpu_dev, num_clks, clks); + if (ret) + goto put_node; + + arm_reg = regulator_get(cpu_dev, "arm"); + pu_reg = regulator_get_optional(cpu_dev, "pu"); + soc_reg = regulator_get(cpu_dev, "soc"); + if (PTR_ERR(arm_reg) == -EPROBE_DEFER || + PTR_ERR(soc_reg) == -EPROBE_DEFER || + PTR_ERR(pu_reg) == -EPROBE_DEFER) { + ret = -EPROBE_DEFER; + dev_dbg(cpu_dev, "regulators not ready, defer\n"); + goto put_reg; + } + if (IS_ERR(arm_reg) || IS_ERR(soc_reg)) { + dev_err(cpu_dev, "failed to get regulators\n"); + ret = -ENOENT; + goto put_reg; + } + + ret = dev_pm_opp_of_add_table(cpu_dev); + if (ret < 0) { + dev_err(cpu_dev, "failed to init OPP table: %d\n", ret); + goto put_reg; + } + + if (of_machine_is_compatible("fsl,imx6ul") || + of_machine_is_compatible("fsl,imx6ull")) { + ret = imx6ul_opp_check_speed_grading(cpu_dev); + } else { + ret = imx6q_opp_check_speed_grading(cpu_dev); + } + if (ret) { + dev_err_probe(cpu_dev, ret, "failed to read ocotp\n"); + goto out_free_opp; + } + + num = dev_pm_opp_get_opp_count(cpu_dev); + if (num < 0) { + ret = num; + dev_err(cpu_dev, "no OPP table is found: %d\n", ret); + goto out_free_opp; + } + + ret = dev_pm_opp_init_cpufreq_table(cpu_dev, &freq_table); + if (ret) { + dev_err(cpu_dev, "failed to init cpufreq table: %d\n", ret); + goto out_free_opp; + } + + /* Make imx6_soc_volt array's size same as arm opp number */ + imx6_soc_volt = devm_kcalloc(cpu_dev, num, sizeof(*imx6_soc_volt), + GFP_KERNEL); + if (imx6_soc_volt == NULL) { + ret = -ENOMEM; + goto free_freq_table; + } + + prop = of_find_property(np, "fsl,soc-operating-points", NULL); + if (!prop || !prop->value) + goto soc_opp_out; + + /* + * Each OPP is a set of tuples consisting of frequency and + * voltage like <freq-kHz vol-uV>. + */ + nr = prop->length / sizeof(u32); + if (nr % 2 || (nr / 2) < num) + goto soc_opp_out; + + for (j = 0; j < num; j++) { + val = prop->value; + for (i = 0; i < nr / 2; i++) { + unsigned long freq = be32_to_cpup(val++); + unsigned long volt = be32_to_cpup(val++); + if (freq_table[j].frequency == freq) { + imx6_soc_volt[soc_opp_count++] = volt; + break; + } + } + } + +soc_opp_out: + /* use fixed soc opp volt if no valid soc opp info found in dtb */ + if (soc_opp_count != num) { + dev_warn(cpu_dev, "can NOT find valid fsl,soc-operating-points property in dtb, use default value!\n"); + for (j = 0; j < num; j++) + imx6_soc_volt[j] = PU_SOC_VOLTAGE_NORMAL; + if (freq_table[num - 1].frequency * 1000 == FREQ_1P2_GHZ) + imx6_soc_volt[num - 1] = PU_SOC_VOLTAGE_HIGH; + } + + if (of_property_read_u32(np, "clock-latency", &transition_latency)) + transition_latency = CPUFREQ_ETERNAL; + + /* + * Calculate the ramp time for max voltage change in the + * VDDSOC and VDDPU regulators. + */ + ret = regulator_set_voltage_time(soc_reg, imx6_soc_volt[0], imx6_soc_volt[num - 1]); + if (ret > 0) + transition_latency += ret * 1000; + if (!IS_ERR(pu_reg)) { + ret = regulator_set_voltage_time(pu_reg, imx6_soc_volt[0], imx6_soc_volt[num - 1]); + if (ret > 0) + transition_latency += ret * 1000; + } + + /* + * OPP is maintained in order of increasing frequency, and + * freq_table initialised from OPP is therefore sorted in the + * same order. + */ + max_freq = freq_table[--num].frequency; + opp = dev_pm_opp_find_freq_exact(cpu_dev, + freq_table[0].frequency * 1000, true); + min_volt = dev_pm_opp_get_voltage(opp); + dev_pm_opp_put(opp); + opp = dev_pm_opp_find_freq_exact(cpu_dev, max_freq * 1000, true); + max_volt = dev_pm_opp_get_voltage(opp); + dev_pm_opp_put(opp); + + ret = regulator_set_voltage_time(arm_reg, min_volt, max_volt); + if (ret > 0) + transition_latency += ret * 1000; + + ret = cpufreq_register_driver(&imx6q_cpufreq_driver); + if (ret) { + dev_err(cpu_dev, "failed register driver: %d\n", ret); + goto free_freq_table; + } + + of_node_put(np); + return 0; + +free_freq_table: + dev_pm_opp_free_cpufreq_table(cpu_dev, &freq_table); +out_free_opp: + dev_pm_opp_of_remove_table(cpu_dev); +put_reg: + if (!IS_ERR(arm_reg)) + regulator_put(arm_reg); + if (!IS_ERR(pu_reg)) + regulator_put(pu_reg); + if (!IS_ERR(soc_reg)) + regulator_put(soc_reg); + + clk_bulk_put(num_clks, clks); +put_node: + of_node_put(np); + + return ret; +} + +static int imx6q_cpufreq_remove(struct platform_device *pdev) +{ + cpufreq_unregister_driver(&imx6q_cpufreq_driver); + dev_pm_opp_free_cpufreq_table(cpu_dev, &freq_table); + dev_pm_opp_of_remove_table(cpu_dev); + regulator_put(arm_reg); + if (!IS_ERR(pu_reg)) + regulator_put(pu_reg); + regulator_put(soc_reg); + + clk_bulk_put(num_clks, clks); + + return 0; +} + +static struct platform_driver imx6q_cpufreq_platdrv = { + .driver = { + .name = "imx6q-cpufreq", + }, + .probe = imx6q_cpufreq_probe, + .remove = imx6q_cpufreq_remove, +}; +module_platform_driver(imx6q_cpufreq_platdrv); + +MODULE_ALIAS("platform:imx6q-cpufreq"); +MODULE_AUTHOR("Shawn Guo <shawn.guo@linaro.org>"); +MODULE_DESCRIPTION("Freescale i.MX6Q cpufreq driver"); +MODULE_LICENSE("GPL"); |