cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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imx-cpufreq-dt.c (5458B)


      1// SPDX-License-Identifier: GPL-2.0
      2/*
      3 * Copyright 2019 NXP
      4 */
      5
      6#include <linux/clk.h>
      7#include <linux/cpu.h>
      8#include <linux/cpufreq.h>
      9#include <linux/err.h>
     10#include <linux/init.h>
     11#include <linux/kernel.h>
     12#include <linux/module.h>
     13#include <linux/nvmem-consumer.h>
     14#include <linux/of.h>
     15#include <linux/platform_device.h>
     16#include <linux/pm_opp.h>
     17#include <linux/regulator/consumer.h>
     18#include <linux/slab.h>
     19
     20#include "cpufreq-dt.h"
     21
     22#define OCOTP_CFG3_SPEED_GRADE_SHIFT	8
     23#define OCOTP_CFG3_SPEED_GRADE_MASK	(0x3 << 8)
     24#define IMX8MN_OCOTP_CFG3_SPEED_GRADE_MASK	(0xf << 8)
     25#define OCOTP_CFG3_MKT_SEGMENT_SHIFT    6
     26#define OCOTP_CFG3_MKT_SEGMENT_MASK     (0x3 << 6)
     27#define IMX8MP_OCOTP_CFG3_MKT_SEGMENT_SHIFT    5
     28#define IMX8MP_OCOTP_CFG3_MKT_SEGMENT_MASK     (0x3 << 5)
     29
     30#define IMX7ULP_MAX_RUN_FREQ	528000
     31
     32/* cpufreq-dt device registered by imx-cpufreq-dt */
     33static struct platform_device *cpufreq_dt_pdev;
     34static struct opp_table *cpufreq_opp_table;
     35static struct device *cpu_dev;
     36
     37enum IMX7ULP_CPUFREQ_CLKS {
     38	ARM,
     39	CORE,
     40	SCS_SEL,
     41	HSRUN_CORE,
     42	HSRUN_SCS_SEL,
     43	FIRC,
     44};
     45
     46static struct clk_bulk_data imx7ulp_clks[] = {
     47	{ .id = "arm" },
     48	{ .id = "core" },
     49	{ .id = "scs_sel" },
     50	{ .id = "hsrun_core" },
     51	{ .id = "hsrun_scs_sel" },
     52	{ .id = "firc" },
     53};
     54
     55static unsigned int imx7ulp_get_intermediate(struct cpufreq_policy *policy,
     56					     unsigned int index)
     57{
     58	return clk_get_rate(imx7ulp_clks[FIRC].clk);
     59}
     60
     61static int imx7ulp_target_intermediate(struct cpufreq_policy *policy,
     62					unsigned int index)
     63{
     64	unsigned int newfreq = policy->freq_table[index].frequency;
     65
     66	clk_set_parent(imx7ulp_clks[SCS_SEL].clk, imx7ulp_clks[FIRC].clk);
     67	clk_set_parent(imx7ulp_clks[HSRUN_SCS_SEL].clk, imx7ulp_clks[FIRC].clk);
     68
     69	if (newfreq > IMX7ULP_MAX_RUN_FREQ)
     70		clk_set_parent(imx7ulp_clks[ARM].clk,
     71			       imx7ulp_clks[HSRUN_CORE].clk);
     72	else
     73		clk_set_parent(imx7ulp_clks[ARM].clk, imx7ulp_clks[CORE].clk);
     74
     75	return 0;
     76}
     77
     78static struct cpufreq_dt_platform_data imx7ulp_data = {
     79	.target_intermediate = imx7ulp_target_intermediate,
     80	.get_intermediate = imx7ulp_get_intermediate,
     81};
     82
     83static int imx_cpufreq_dt_probe(struct platform_device *pdev)
     84{
     85	struct platform_device *dt_pdev;
     86	u32 cell_value, supported_hw[2];
     87	int speed_grade, mkt_segment;
     88	int ret;
     89
     90	cpu_dev = get_cpu_device(0);
     91
     92	if (!of_find_property(cpu_dev->of_node, "cpu-supply", NULL))
     93		return -ENODEV;
     94
     95	if (of_machine_is_compatible("fsl,imx7ulp")) {
     96		ret = clk_bulk_get(cpu_dev, ARRAY_SIZE(imx7ulp_clks),
     97				   imx7ulp_clks);
     98		if (ret)
     99			return ret;
    100
    101		dt_pdev = platform_device_register_data(NULL, "cpufreq-dt",
    102							-1, &imx7ulp_data,
    103							sizeof(imx7ulp_data));
    104		if (IS_ERR(dt_pdev)) {
    105			clk_bulk_put(ARRAY_SIZE(imx7ulp_clks), imx7ulp_clks);
    106			ret = PTR_ERR(dt_pdev);
    107			dev_err(&pdev->dev, "Failed to register cpufreq-dt: %d\n", ret);
    108			return ret;
    109		}
    110
    111		cpufreq_dt_pdev = dt_pdev;
    112
    113		return 0;
    114	}
    115
    116	ret = nvmem_cell_read_u32(cpu_dev, "speed_grade", &cell_value);
    117	if (ret)
    118		return ret;
    119
    120	if (of_machine_is_compatible("fsl,imx8mn") ||
    121	    of_machine_is_compatible("fsl,imx8mp"))
    122		speed_grade = (cell_value & IMX8MN_OCOTP_CFG3_SPEED_GRADE_MASK)
    123			      >> OCOTP_CFG3_SPEED_GRADE_SHIFT;
    124	else
    125		speed_grade = (cell_value & OCOTP_CFG3_SPEED_GRADE_MASK)
    126			      >> OCOTP_CFG3_SPEED_GRADE_SHIFT;
    127
    128	if (of_machine_is_compatible("fsl,imx8mp"))
    129		mkt_segment = (cell_value & IMX8MP_OCOTP_CFG3_MKT_SEGMENT_MASK)
    130			       >> IMX8MP_OCOTP_CFG3_MKT_SEGMENT_SHIFT;
    131	else
    132		mkt_segment = (cell_value & OCOTP_CFG3_MKT_SEGMENT_MASK)
    133			       >> OCOTP_CFG3_MKT_SEGMENT_SHIFT;
    134
    135	/*
    136	 * Early samples without fuses written report "0 0" which may NOT
    137	 * match any OPP defined in DT. So clamp to minimum OPP defined in
    138	 * DT to avoid warning for "no OPPs".
    139	 *
    140	 * Applies to i.MX8M series SoCs.
    141	 */
    142	if (mkt_segment == 0 && speed_grade == 0) {
    143		if (of_machine_is_compatible("fsl,imx8mm") ||
    144		    of_machine_is_compatible("fsl,imx8mq"))
    145			speed_grade = 1;
    146		if (of_machine_is_compatible("fsl,imx8mn") ||
    147		    of_machine_is_compatible("fsl,imx8mp"))
    148			speed_grade = 0xb;
    149	}
    150
    151	supported_hw[0] = BIT(speed_grade);
    152	supported_hw[1] = BIT(mkt_segment);
    153	dev_info(&pdev->dev, "cpu speed grade %d mkt segment %d supported-hw %#x %#x\n",
    154			speed_grade, mkt_segment, supported_hw[0], supported_hw[1]);
    155
    156	cpufreq_opp_table = dev_pm_opp_set_supported_hw(cpu_dev, supported_hw, 2);
    157	if (IS_ERR(cpufreq_opp_table)) {
    158		ret = PTR_ERR(cpufreq_opp_table);
    159		dev_err(&pdev->dev, "Failed to set supported opp: %d\n", ret);
    160		return ret;
    161	}
    162
    163	cpufreq_dt_pdev = platform_device_register_data(
    164			&pdev->dev, "cpufreq-dt", -1, NULL, 0);
    165	if (IS_ERR(cpufreq_dt_pdev)) {
    166		dev_pm_opp_put_supported_hw(cpufreq_opp_table);
    167		ret = PTR_ERR(cpufreq_dt_pdev);
    168		dev_err(&pdev->dev, "Failed to register cpufreq-dt: %d\n", ret);
    169		return ret;
    170	}
    171
    172	return 0;
    173}
    174
    175static int imx_cpufreq_dt_remove(struct platform_device *pdev)
    176{
    177	platform_device_unregister(cpufreq_dt_pdev);
    178	if (!of_machine_is_compatible("fsl,imx7ulp"))
    179		dev_pm_opp_put_supported_hw(cpufreq_opp_table);
    180	else
    181		clk_bulk_put(ARRAY_SIZE(imx7ulp_clks), imx7ulp_clks);
    182
    183	return 0;
    184}
    185
    186static struct platform_driver imx_cpufreq_dt_driver = {
    187	.probe = imx_cpufreq_dt_probe,
    188	.remove = imx_cpufreq_dt_remove,
    189	.driver = {
    190		.name = "imx-cpufreq-dt",
    191	},
    192};
    193module_platform_driver(imx_cpufreq_dt_driver);
    194
    195MODULE_ALIAS("platform:imx-cpufreq-dt");
    196MODULE_DESCRIPTION("Freescale i.MX cpufreq speed grading driver");
    197MODULE_LICENSE("GPL v2");