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Release 4.7 drivers/clk/tegra/clk-dfll.c

/*
 * clk-dfll.c - Tegra DFLL clock source common code
 *
 * Copyright (C) 2012-2014 NVIDIA Corporation. All rights reserved.
 *
 * Aleksandr Frid <afrid@nvidia.com>
 * Paul Walmsley <pwalmsley@nvidia.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
 * more details.
 *
 * This library is for the DVCO and DFLL IP blocks on the Tegra124
 * SoC. These IP blocks together are also known at NVIDIA as
 * "CL-DVFS". To try to avoid confusion, this code refers to them
 * collectively as the "DFLL."
 *
 * The DFLL is a root clocksource which tolerates some amount of
 * supply voltage noise. Tegra124 uses it to clock the fast CPU
 * complex when the target CPU speed is above a particular rate. The
 * DFLL can be operated in either open-loop mode or closed-loop mode.
 * In open-loop mode, the DFLL generates an output clock appropriate
 * to the supply voltage. In closed-loop mode, when configured with a
 * target frequency, the DFLL minimizes supply voltage while
 * delivering an average frequency equal to the target.
 *
 * Devices clocked by the DFLL must be able to tolerate frequency
 * variation. In the case of the CPU, it's important to note that the
 * CPU cycle time will vary. This has implications for
 * performance-measurement code and any code that relies on the CPU
 * cycle time to delay for a certain length of time.
 *
 */

#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/debugfs.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/pm_opp.h>
#include <linux/pm_runtime.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#include <linux/reset.h>
#include <linux/seq_file.h>

#include "clk-dfll.h"
#include "cvb.h"

/*
 * DFLL control registers - access via dfll_{readl,writel}
 */

/* DFLL_CTRL: DFLL control register */

#define DFLL_CTRL			0x00

#define DFLL_CTRL_MODE_MASK		0x03

/* DFLL_CONFIG: DFLL sample rate control */

#define DFLL_CONFIG			0x04

#define DFLL_CONFIG_DIV_MASK		0xff

#define DFLL_CONFIG_DIV_PRESCALE	32

/* DFLL_PARAMS: tuning coefficients for closed loop integrator */

#define DFLL_PARAMS			0x08

#define DFLL_PARAMS_CG_SCALE		(0x1 << 24)

#define DFLL_PARAMS_FORCE_MODE_SHIFT	22

#define DFLL_PARAMS_FORCE_MODE_MASK	(0x3 << DFLL_PARAMS_FORCE_MODE_SHIFT)

#define DFLL_PARAMS_CF_PARAM_SHIFT	16

#define DFLL_PARAMS_CF_PARAM_MASK	(0x3f << DFLL_PARAMS_CF_PARAM_SHIFT)

#define DFLL_PARAMS_CI_PARAM_SHIFT	8

#define DFLL_PARAMS_CI_PARAM_MASK	(0x7 << DFLL_PARAMS_CI_PARAM_SHIFT)

#define DFLL_PARAMS_CG_PARAM_SHIFT	0

#define DFLL_PARAMS_CG_PARAM_MASK	(0xff << DFLL_PARAMS_CG_PARAM_SHIFT)

/* DFLL_TUNE0: delay line configuration register 0 */

#define DFLL_TUNE0			0x0c

/* DFLL_TUNE1: delay line configuration register 1 */

#define DFLL_TUNE1			0x10

/* DFLL_FREQ_REQ: target DFLL frequency control */

#define DFLL_FREQ_REQ			0x14

#define DFLL_FREQ_REQ_FORCE_ENABLE	(0x1 << 28)

#define DFLL_FREQ_REQ_FORCE_SHIFT	16

#define DFLL_FREQ_REQ_FORCE_MASK	(0xfff << DFLL_FREQ_REQ_FORCE_SHIFT)

#define FORCE_MAX			2047

#define FORCE_MIN			-2048

#define DFLL_FREQ_REQ_SCALE_SHIFT	8

#define DFLL_FREQ_REQ_SCALE_MASK	(0xff << DFLL_FREQ_REQ_SCALE_SHIFT)

#define DFLL_FREQ_REQ_SCALE_MAX		256

#define DFLL_FREQ_REQ_FREQ_VALID	(0x1 << 7)

#define DFLL_FREQ_REQ_MULT_SHIFT	0

#define DFLL_FREQ_REG_MULT_MASK		(0x7f << DFLL_FREQ_REQ_MULT_SHIFT)

#define FREQ_MAX			127

/* DFLL_DROOP_CTRL: droop prevention control */

#define DFLL_DROOP_CTRL			0x1c

/* DFLL_OUTPUT_CFG: closed loop mode control registers */
/* NOTE: access via dfll_i2c_{readl,writel} */

#define DFLL_OUTPUT_CFG			0x20

#define DFLL_OUTPUT_CFG_I2C_ENABLE	(0x1 << 30)

#define OUT_MASK			0x3f

#define DFLL_OUTPUT_CFG_SAFE_SHIFT	24

#define DFLL_OUTPUT_CFG_SAFE_MASK	\
		(OUT_MASK << DFLL_OUTPUT_CFG_SAFE_SHIFT)

#define DFLL_OUTPUT_CFG_MAX_SHIFT	16

#define DFLL_OUTPUT_CFG_MAX_MASK	\
		(OUT_MASK << DFLL_OUTPUT_CFG_MAX_SHIFT)

#define DFLL_OUTPUT_CFG_MIN_SHIFT	8

#define DFLL_OUTPUT_CFG_MIN_MASK	\
		(OUT_MASK << DFLL_OUTPUT_CFG_MIN_SHIFT)

#define DFLL_OUTPUT_CFG_PWM_DELTA	(0x1 << 7)

#define DFLL_OUTPUT_CFG_PWM_ENABLE	(0x1 << 6)

#define DFLL_OUTPUT_CFG_PWM_DIV_SHIFT	0

#define DFLL_OUTPUT_CFG_PWM_DIV_MASK	\
		(OUT_MASK << DFLL_OUTPUT_CFG_PWM_DIV_SHIFT)

/* DFLL_OUTPUT_FORCE: closed loop mode voltage forcing control */

#define DFLL_OUTPUT_FORCE		0x24

#define DFLL_OUTPUT_FORCE_ENABLE	(0x1 << 6)

#define DFLL_OUTPUT_FORCE_VALUE_SHIFT	0

#define DFLL_OUTPUT_FORCE_VALUE_MASK	\
		(OUT_MASK << DFLL_OUTPUT_FORCE_VALUE_SHIFT)

/* DFLL_MONITOR_CTRL: internal monitor data source control */

#define DFLL_MONITOR_CTRL		0x28

#define DFLL_MONITOR_CTRL_FREQ		6

/* DFLL_MONITOR_DATA: internal monitor data output */

#define DFLL_MONITOR_DATA		0x2c

#define DFLL_MONITOR_DATA_NEW_MASK	(0x1 << 16)

#define DFLL_MONITOR_DATA_VAL_SHIFT	0

#define DFLL_MONITOR_DATA_VAL_MASK	(0xFFFF << DFLL_MONITOR_DATA_VAL_SHIFT)

/*
 * I2C output control registers - access via dfll_i2c_{readl,writel}
 */

/* DFLL_I2C_CFG: I2C controller configuration register */

#define DFLL_I2C_CFG			0x40

#define DFLL_I2C_CFG_ARB_ENABLE		(0x1 << 20)

#define DFLL_I2C_CFG_HS_CODE_SHIFT	16

#define DFLL_I2C_CFG_HS_CODE_MASK	(0x7 << DFLL_I2C_CFG_HS_CODE_SHIFT)

#define DFLL_I2C_CFG_PACKET_ENABLE	(0x1 << 15)

#define DFLL_I2C_CFG_SIZE_SHIFT		12

#define DFLL_I2C_CFG_SIZE_MASK		(0x7 << DFLL_I2C_CFG_SIZE_SHIFT)

#define DFLL_I2C_CFG_SLAVE_ADDR_10	(0x1 << 10)

#define DFLL_I2C_CFG_SLAVE_ADDR_SHIFT_7BIT	1

#define DFLL_I2C_CFG_SLAVE_ADDR_SHIFT_10BIT	0

/* DFLL_I2C_VDD_REG_ADDR: PMIC I2C address for closed loop mode */

#define DFLL_I2C_VDD_REG_ADDR		0x44

/* DFLL_I2C_STS: I2C controller status */

#define DFLL_I2C_STS			0x48

#define DFLL_I2C_STS_I2C_LAST_SHIFT	1

#define DFLL_I2C_STS_I2C_REQ_PENDING	0x1

/* DFLL_INTR_STS: DFLL interrupt status register */

#define DFLL_INTR_STS			0x5c

/* DFLL_INTR_EN: DFLL interrupt enable register */

#define DFLL_INTR_EN			0x60

#define DFLL_INTR_MIN_MASK		0x1

#define DFLL_INTR_MAX_MASK		0x2

/*
 * Integrated I2C controller registers - relative to td->i2c_controller_base
 */

/* DFLL_I2C_CLK_DIVISOR: I2C controller clock divisor */

#define DFLL_I2C_CLK_DIVISOR		0x6c

#define DFLL_I2C_CLK_DIVISOR_MASK	0xffff

#define DFLL_I2C_CLK_DIVISOR_FS_SHIFT	16

#define DFLL_I2C_CLK_DIVISOR_HS_SHIFT	0

#define DFLL_I2C_CLK_DIVISOR_PREDIV	8

#define DFLL_I2C_CLK_DIVISOR_HSMODE_PREDIV	12

/*
 * Other constants
 */

/* MAX_DFLL_VOLTAGES: number of LUT entries in the DFLL IP block */

#define MAX_DFLL_VOLTAGES		33

/*
 * REF_CLK_CYC_PER_DVCO_SAMPLE: the number of ref_clk cycles that the hardware
 *    integrates the DVCO counter over - used for debug rate monitoring and
 *    droop control
 */

#define REF_CLK_CYC_PER_DVCO_SAMPLE	4

/*
 * REF_CLOCK_RATE: the DFLL reference clock rate currently supported by this
 * driver, in Hz
 */

#define REF_CLOCK_RATE			51000000UL


#define DVCO_RATE_TO_MULT(rate, ref_rate)	((rate) / ((ref_rate) / 2))

#define MULT_TO_DVCO_RATE(mult, ref_rate)	((mult) * ((ref_rate) / 2))

/**
 * enum dfll_ctrl_mode - DFLL hardware operating mode
 * @DFLL_UNINITIALIZED: (uninitialized state - not in hardware bitfield)
 * @DFLL_DISABLED: DFLL not generating an output clock
 * @DFLL_OPEN_LOOP: DVCO running, but DFLL not adjusting voltage
 * @DFLL_CLOSED_LOOP: DVCO running, and DFLL adjusting voltage to match
 *                    the requested rate
 *
 * The integer corresponding to the last two states, minus one, is
 * written to the DFLL hardware to change operating modes.
 */

enum dfll_ctrl_mode {
	
DFLL_UNINITIALIZED = 0,
	
DFLL_DISABLED = 1,
	
DFLL_OPEN_LOOP = 2,
	
DFLL_CLOSED_LOOP = 3,
};

/**
 * enum dfll_tune_range - voltage range that the driver believes it's in
 * @DFLL_TUNE_UNINITIALIZED: DFLL tuning not yet programmed
 * @DFLL_TUNE_LOW: DFLL in the low-voltage range (or open-loop mode)
 *
 * Some DFLL tuning parameters may need to change depending on the
 * DVCO's voltage; these states represent the ranges that the driver
 * supports. These are software states; these values are never
 * written into registers.
 */

enum dfll_tune_range {
	
DFLL_TUNE_UNINITIALIZED = 0,
	
DFLL_TUNE_LOW = 1,
};

/**
 * struct dfll_rate_req - target DFLL rate request data
 * @rate: target frequency, after the postscaling
 * @dvco_target_rate: target frequency, after the postscaling
 * @lut_index: LUT index at which voltage the dvco_target_rate will be reached
 * @mult_bits: value to program to the MULT bits of the DFLL_FREQ_REQ register
 * @scale_bits: value to program to the SCALE bits of the DFLL_FREQ_REQ register
 */

struct dfll_rate_req {
	
unsigned long rate;
	
unsigned long dvco_target_rate;
	
int lut_index;
	
u8 mult_bits;
	
u8 scale_bits;
};


struct tegra_dfll {
	
struct device			*dev;
	
struct tegra_dfll_soc_data	*soc;

	
void __iomem			*base;
	
void __iomem			*i2c_base;
	
void __iomem			*i2c_controller_base;
	
void __iomem			*lut_base;

	
struct regulator		*vdd_reg;
	
struct clk			*soc_clk;
	
struct clk			*ref_clk;
	
struct clk			*i2c_clk;
	
struct clk			*dfll_clk;
	
struct reset_control		*dvco_rst;
	
unsigned long			ref_rate;
	
unsigned long			i2c_clk_rate;
	
unsigned long			dvco_rate_min;

	
enum dfll_ctrl_mode		mode;
	
enum dfll_tune_range		tune_range;
	
struct dentry			*debugfs_dir;
	
struct clk_hw			dfll_clk_hw;
	
const char			*output_clock_name;
	
struct dfll_rate_req		last_req;
	
unsigned long			last_unrounded_rate;

	/* Parameters from DT */
	
u32				droop_ctrl;
	
u32				sample_rate;
	
u32				force_mode;
	
u32				cf;
	
u32				ci;
	
u32				cg;
	
bool				cg_scale;

	/* I2C interface parameters */
	
u32				i2c_fs_rate;
	
u32				i2c_reg;
	
u32				i2c_slave_addr;

	/* i2c_lut array entries are regulator framework selectors */
	
unsigned			i2c_lut[MAX_DFLL_VOLTAGES];
	
int				i2c_lut_size;
	


u8				lut_min, lut_max, lut_safe;
};


#define clk_hw_to_dfll(_hw) container_of(_hw, struct tegra_dfll, dfll_clk_hw)

/* mode_name: map numeric DFLL modes to names for friendly console messages */

static const char * const mode_name[] = {
	[DFLL_UNINITIALIZED] = "uninitialized",
	[DFLL_DISABLED] = "disabled",
	[DFLL_OPEN_LOOP] = "open_loop",
	[DFLL_CLOSED_LOOP] = "closed_loop",
};

/*
 * Register accessors
 */


static inline u32 dfll_readl(struct tegra_dfll *td, u32 offs) { return __raw_readl(td->base + offs); }

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static inline void dfll_writel(struct tegra_dfll *td, u32 val, u32 offs) { WARN_ON(offs >= DFLL_I2C_CFG); __raw_writel(val, td->base + offs); }

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static inline void dfll_wmb(struct tegra_dfll *td) { dfll_readl(td, DFLL_CTRL); }

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/* I2C output control registers - for addresses above DFLL_I2C_CFG */
static inline u32 dfll_i2c_readl(struct tegra_dfll *td, u32 offs) { return __raw_readl(td->i2c_base + offs); }

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static inline void dfll_i2c_writel(struct tegra_dfll *td, u32 val, u32 offs) { __raw_writel(val, td->i2c_base + offs); }

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static inline void dfll_i2c_wmb(struct tegra_dfll *td) { dfll_i2c_readl(td, DFLL_I2C_CFG); }

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/** * dfll_is_running - is the DFLL currently generating a clock? * @td: DFLL instance * * If the DFLL is currently generating an output clock signal, return * true; otherwise return false. */
static bool dfll_is_running(struct tegra_dfll *td) { return td->mode >= DFLL_OPEN_LOOP; }

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/* * Runtime PM suspend/resume callbacks */ /** * tegra_dfll_runtime_resume - enable all clocks needed by the DFLL * @dev: DFLL device * * * Enable all clocks needed by the DFLL. Assumes that clk_prepare() * has already been called on all the clocks. * * XXX Should also handle context restore when returning from off. */
int tegra_dfll_runtime_resume(struct device *dev) { struct tegra_dfll *td = dev_get_drvdata(dev); int ret; ret = clk_enable(td->ref_clk); if (ret) { dev_err(dev, "could not enable ref clock: %d\n", ret); return ret; } ret = clk_enable(td->soc_clk); if (ret) { dev_err(dev, "could not enable register clock: %d\n", ret); clk_disable(td->ref_clk); return ret; } ret = clk_enable(td->i2c_clk); if (ret) { dev_err(dev, "could not enable i2c clock: %d\n", ret); clk_disable(td->soc_clk); clk_disable(td->ref_clk); return ret; } return 0; }

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EXPORT_SYMBOL(tegra_dfll_runtime_resume); /** * tegra_dfll_runtime_suspend - disable all clocks needed by the DFLL * @dev: DFLL device * * * Disable all clocks needed by the DFLL. Assumes that other code * will later call clk_unprepare(). */
int tegra_dfll_runtime_suspend(struct device *dev) { struct tegra_dfll *td = dev_get_drvdata(dev); clk_disable(td->ref_clk); clk_disable(td->soc_clk); clk_disable(td->i2c_clk); return 0; }

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EXPORT_SYMBOL(tegra_dfll_runtime_suspend); /* * DFLL tuning operations (per-voltage-range tuning settings) */ /** * dfll_tune_low - tune to DFLL and CPU settings valid for any voltage * @td: DFLL instance * * Tune the DFLL oscillator parameters and the CPU clock shaper for * the low-voltage range. These settings are valid for any voltage, * but may not be optimal. */
static void dfll_tune_low(struct tegra_dfll *td) { td->tune_range = DFLL_TUNE_LOW; dfll_writel(td, td->soc->cvb->cpu_dfll_data.tune0_low, DFLL_TUNE0); dfll_writel(td, td->soc->cvb->cpu_dfll_data.tune1, DFLL_TUNE1); dfll_wmb(td); if (td->soc->set_clock_trimmers_low) td->soc->set_clock_trimmers_low(); }

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/* * Output clock scaler helpers */ /** * dfll_scale_dvco_rate - calculate scaled rate from the DVCO rate * @scale_bits: clock scaler value (bits in the DFLL_FREQ_REQ_SCALE field) * @dvco_rate: the DVCO rate * * Apply the same scaling formula that the DFLL hardware uses to scale * the DVCO rate. */
static unsigned long dfll_scale_dvco_rate(int scale_bits, unsigned long dvco_rate) { return (u64)dvco_rate * (scale_bits + 1) / DFLL_FREQ_REQ_SCALE_MAX; }

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/* * DFLL mode switching */ /** * dfll_set_mode - change the DFLL control mode * @td: DFLL instance * @mode: DFLL control mode (see enum dfll_ctrl_mode) * * Change the DFLL's operating mode between disabled, open-loop mode, * and closed-loop mode, or vice versa. */
static void dfll_set_mode(struct tegra_dfll *td, enum dfll_ctrl_mode mode) { td->mode = mode; dfll_writel(td, mode - 1, DFLL_CTRL); dfll_wmb(td); }

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/* * DFLL-to-I2C controller interface */ /** * dfll_i2c_set_output_enabled - enable/disable I2C PMIC voltage requests * @td: DFLL instance * @enable: whether to enable or disable the I2C voltage requests * * Set the master enable control for I2C control value updates. If disabled, * then I2C control messages are inhibited, regardless of the DFLL mode. */
static int dfll_i2c_set_output_enabled(struct tegra_dfll *td, bool enable) { u32 val; val = dfll_i2c_readl(td, DFLL_OUTPUT_CFG); if (enable) val |= DFLL_OUTPUT_CFG_I2C_ENABLE; else val &= ~DFLL_OUTPUT_CFG_I2C_ENABLE; dfll_i2c_writel(td, val, DFLL_OUTPUT_CFG); dfll_i2c_wmb(td); return 0; }

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/** * dfll_load_lut - load the voltage lookup table * @td: struct tegra_dfll * * * Load the voltage-to-PMIC register value lookup table into the DFLL * IP block memory. Look-up tables can be loaded at any time. */
static void dfll_load_i2c_lut(struct tegra_dfll *td) { int i, lut_index; u32 val; for (i = 0; i < MAX_DFLL_VOLTAGES; i++) { if (i < td->lut_min) lut_index = td->lut_min; else if (i > td->lut_max) lut_index = td->lut_max; else lut_index = i; val = regulator_list_hardware_vsel(td->vdd_reg, td->i2c_lut[lut_index]); __raw_writel(val, td->lut_base + i * 4); } dfll_i2c_wmb(td); }

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/** * dfll_init_i2c_if - set up the DFLL's DFLL-I2C interface * @td: DFLL instance * * During DFLL driver initialization, program the DFLL-I2C interface * with the PMU slave address, vdd register offset, and transfer mode. * This data is used by the DFLL to automatically construct I2C * voltage-set commands, which are then passed to the DFLL's internal * I2C controller. */
static void dfll_init_i2c_if(struct tegra_dfll *td) { u32 val; if (td->i2c_slave_addr > 0x7f) { val = td->i2c_slave_addr << DFLL_I2C_CFG_SLAVE_ADDR_SHIFT_10BIT; val |= DFLL_I2C_CFG_SLAVE_ADDR_10; } else { val = td->i2c_slave_addr << DFLL_I2C_CFG_SLAVE_ADDR_SHIFT_7BIT; } val |= DFLL_I2C_CFG_SIZE_MASK; val |= DFLL_I2C_CFG_ARB_ENABLE; dfll_i2c_writel(td, val, DFLL_I2C_CFG); dfll_i2c_writel(td, td->i2c_reg, DFLL_I2C_VDD_REG_ADDR); val = DIV_ROUND_UP(td->i2c_clk_rate, td->i2c_fs_rate * 8); BUG_ON(!val || (val > DFLL_I2C_CLK_DIVISOR_MASK)); val = (val - 1) << DFLL_I2C_CLK_DIVISOR_FS_SHIFT; /* default hs divisor just in case */ val |= 1 << DFLL_I2C_CLK_DIVISOR_HS_SHIFT; __raw_writel(val, td->i2c_controller_base + DFLL_I2C_CLK_DIVISOR); dfll_i2c_wmb(td); }

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/** * dfll_init_out_if - prepare DFLL-to-PMIC interface * @td: DFLL instance * * During DFLL driver initialization or resume from context loss, * disable the I2C command output to the PMIC, set safe voltage and * output limits, and disable and clear limit interrupts. */
static void dfll_init_out_if(struct tegra_dfll *td) { u32 val; td->lut_min = 0; td->lut_max = td->i2c_lut_size - 1; td->lut_safe = td->lut_min + 1; dfll_i2c_writel(td, 0, DFLL_OUTPUT_CFG); val = (td->lut_safe << DFLL_OUTPUT_CFG_SAFE_SHIFT) | (td->lut_max << DFLL_OUTPUT_CFG_MAX_SHIFT) | (td->lut_min << DFLL_OUTPUT_CFG_MIN_SHIFT); dfll_i2c_writel(td, val, DFLL_OUTPUT_CFG); dfll_i2c_wmb(td); dfll_writel(td, 0, DFLL_OUTPUT_FORCE); dfll_i2c_writel(td, 0, DFLL_INTR_EN); dfll_i2c_writel(td, DFLL_INTR_MAX_MASK | DFLL_INTR_MIN_MASK, DFLL_INTR_STS); dfll_load_i2c_lut(td); dfll_init_i2c_if(td); }

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/* * Set/get the DFLL's targeted output clock rate */ /** * find_lut_index_for_rate - determine I2C LUT index for given DFLL rate * @td: DFLL instance * @rate: clock rate * * Determines the index of a I2C LUT entry for a voltage that approximately * produces the given DFLL clock rate. This is used when forcing a value * to the integrator during rate changes. Returns -ENOENT if a suitable * LUT index is not found. */
static int find_lut_index_for_rate(struct tegra_dfll *td, unsigned long rate) { struct dev_pm_opp *opp; int i, uv; rcu_read_lock(); opp = dev_pm_opp_find_freq_ceil(td->soc->dev, &rate); if (IS_ERR(opp)) { rcu_read_unlock(); return PTR_ERR(opp); } uv = dev_pm_opp_get_voltage(opp); rcu_read_unlock(); for (i = 0; i < td->i2c_lut_size; i++) { if (regulator_list_voltage(td->vdd_reg, td->i2c_lut[i]) == uv) return i; } return -ENOENT; }

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/** * dfll_calculate_rate_request - calculate DFLL parameters for a given rate * @td: DFLL instance * @req: DFLL-rate-request structure * @rate: the desired DFLL rate * * Populate the DFLL-rate-request record @req fields with the scale_bits * and mult_bits fields, based on the target input rate. Returns 0 upon * success, or -EINVAL if the requested rate in req->rate is too high * or low for the DFLL to generate. */
static int dfll_calculate_rate_request(struct tegra_dfll *td, struct dfll_rate_req *req, unsigned long rate) { u32 val; /* * If requested rate is below the minimum DVCO rate, active the scaler. * In the future the DVCO minimum voltage should be selected based on * chip temperature and the actual minimum rate should be calibrated * at runtime. */ req->scale_bits = DFLL_FREQ_REQ_SCALE_MAX - 1; if (rate < td->dvco_rate_min) { int scale; scale = DIV_ROUND_CLOSEST(rate / 1000 * DFLL_FREQ_REQ_SCALE_MAX, td->dvco_rate_min / 1000); if (!scale) { dev_err(td->dev, "%s: Rate %lu is too low\n", __func__, rate); return -EINVAL; } req->scale_bits = scale - 1; rate = td->dvco_rate_min; } /* Convert requested rate into frequency request and scale settings */ val = DVCO_RATE_TO_MULT(rate, td->ref_rate); if (val > FREQ_MAX) { dev_err(td->dev, "%s: Rate %lu is above dfll range\n", __func__, rate); return -EINVAL; } req->mult_bits = val; req->dvco_target_rate = MULT_TO_DVCO_RATE(req->mult_bits, td->ref_rate); req->rate = dfll_scale_dvco_rate(req->scale_bits, req->dvco_target_rate); req->lut_index = find_lut_index_for_rate(td, req->dvco_target_rate); if (req->lut_index < 0) return req->lut_index; return 0; }

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/** * dfll_set_frequency_request - start the frequency change operation * @td: DFLL instance * @req: rate request structure * * Tell the DFLL to try to change its output frequency to the * frequency represented by @req. DFLL must be in closed-loop mode. */
static void dfll_set_frequency_request(struct tegra_dfll *td, struct dfll_rate_req *req) { u32 val = 0; int force_val; int coef = 128; /* FIXME: td->cg_scale? */; force_val = (req->lut_index - td->lut_safe) * coef / td->cg; force_val = clamp(force_val, FORCE_MIN, FORCE_MAX); val |= req->mult_bits << DFLL_FREQ_REQ_MULT_SHIFT; val |= req->scale_bits << DFLL_FREQ_REQ_SCALE_SHIFT; val |= ((u32)force_val << DFLL_FREQ_REQ_FORCE_SHIFT) & DFLL_FREQ_REQ_FORCE_MASK; val |= DFLL_FREQ_REQ_FREQ_VALID | DFLL_FREQ_REQ_FORCE_ENABLE; dfll_writel(td, val, DFLL_FREQ_REQ); dfll_wmb(td); }

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/** * tegra_dfll_request_rate - set the next rate for the DFLL to tune to * @td: DFLL instance * @rate: clock rate to target * * Convert the requested clock rate @rate into the DFLL control logic * settings. In closed-loop mode, update new settings immediately to * adjust DFLL output rate accordingly. Otherwise, just save them * until the next switch to closed loop. Returns 0 upon success, * -EPERM if the DFLL driver has not yet been initialized, or -EINVAL * if @rate is outside the DFLL's tunable range. */
static int dfll_request_rate(struct tegra_dfll *td, unsigned long rate) { int ret; struct dfll_rate_req req; if (td->mode == DFLL_UNINITIALIZED) { dev_err(td->dev, "%s: Cannot set DFLL rate in %s mode\n", __func__, mode_name[td->mode]); return -EPERM; } ret = dfll_calculate_rate_request(td, &req, rate); if (ret) return ret; td->last_unrounded_rate = rate; td->last_req = req; if (td->mode == DFLL_CLOSED_LOOP) dfll_set_frequency_request(td, &td->last_req); return 0; }

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/* * DFLL enable/disable & open-loop <-> closed-loop transitions */ /** * dfll_disable - switch from open-loop mode to disabled mode * @td: DFLL instance * * Switch from OPEN_LOOP state to DISABLED state. Returns 0 upon success * or -EPERM if the DFLL is not currently in open-loop mode. */
static int dfll_disable(struct tegra_dfll *td) { if (td->mode != DFLL_OPEN_LOOP) { dev_err(td->dev, "cannot disable DFLL in %s mode\n", mode_name[td->mode]); return -EINVAL; } dfll_set_mode(td, DFLL_DISABLED); pm_runtime_put_sync(td->dev); return 0; }

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/** * dfll_enable - switch a disabled DFLL to open-loop mode * @td: DFLL instance * * Switch from DISABLED state to OPEN_LOOP state. Returns 0 upon success * or -EPERM if the DFLL is not currently disabled. */
static int dfll_enable(struct tegra_dfll *td) { if (td->mode != DFLL_DISABLED) { dev_err(td->dev, "cannot enable DFLL in %s mode\n", mode_name[td->mode]); return -EPERM; } pm_runtime_get_sync(td->dev); dfll_set_mode(td, DFLL_OPEN_LOOP); return 0; }

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/** * dfll_set_open_loop_config - prepare to switch to open-loop mode * @td: DFLL instance * * Prepare to switch the DFLL to open-loop mode. This switches the * DFLL to the low-voltage tuning range, ensures that I2C output * forcing is disabled, and disables the output clock rate scaler. * The DFLL's low-voltage tuning range parameters must be * characterized to keep the downstream device stable at any DVCO * input voltage. No return value. */
static void dfll_set_open_loop_config(struct tegra_dfll *td) { u32 val; /* always tune low (safe) in open loop */ if (td->tune_range != DFLL_TUNE_LOW) dfll_tune_low(td); val = dfll_readl(td, DFLL_FREQ_REQ); val |= DFLL_FREQ_REQ_SCALE_MASK; val &= ~DFLL_FREQ_REQ_FORCE_ENABLE; dfll_writel(td, val, DFLL_FREQ_REQ); dfll_wmb(td); }

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/** * tegra_dfll_lock - switch from open-loop to closed-loop mode * @td: DFLL instance * * Switch from OPEN_LOOP state to CLOSED_LOOP state. Returns 0 upon success, * -EINVAL if the DFLL's target rate hasn't been set yet, or -EPERM if the * DFLL is not currently in open-loop mode. */
static int dfll_lock(struct tegra_dfll *td) { struct dfll_rate_req *req = &td->last_req; switch (td->mode) { case DFLL_CLOSED_LOOP: return 0; case DFLL_OPEN_LOOP: if (req->rate == 0) { dev_err(td->dev, "%s: Cannot lock DFLL at rate 0\n", __func__); return -EINVAL; } dfll_i2c_set_output_enabled(td, true); dfll_set_mode(td, DFLL_CLOSED_LOOP); dfll_set_frequency_request(td, req); return 0; default: BUG_ON(td->mode > DFLL_CLOSED_LOOP); dev_err(td->dev, "%s: Cannot lock DFLL in %s mode\n", __func__, mode_name[td->mode]); return -EPERM; } }

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/** * tegra_dfll_unlock - switch from closed-loop to open-loop mode * @td: DFLL instance * * Switch from CLOSED_LOOP state to OPEN_LOOP state. Returns 0 upon success, * or -EPERM if the DFLL is not currently in open-loop mode. */
static int dfll_unlock(struct tegra_dfll *td) { switch (td->mode) { case DFLL_CLOSED_LOOP: dfll_set_open_loop_config(td); dfll_set_mode(td, DFLL_OPEN_LOOP); dfll_i2c_set_output_enabled(td, false); return 0; case DFLL_OPEN_LOOP: return 0; default: BUG_ON(td->mode > DFLL_CLOSED_LOOP); dev_err(td->dev, "%s: Cannot unlock DFLL in %s mode\n", __func__, mode_name[td->mode]); return -EPERM; } }

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/* * Clock framework integration * * When the DFLL is being controlled by the CCF, always enter closed loop * mode when the clk is enabled. This requires that a DFLL rate request * has been set beforehand, which implies that a clk_set_rate() call is * always required before a clk_enable(). */
static int dfll_clk_is_enabled(struct clk_hw *hw) { struct tegra_dfll *td = clk_hw_to_dfll(hw); return dfll_is_running(td); }

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static int dfll_clk_enable(struct clk_hw *hw) { struct tegra_dfll *td = clk_hw_to_dfll(hw); int ret; ret = dfll_enable(td); if (ret) return ret; ret = dfll_lock(td); if (ret) dfll_disable(td); return ret; }

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static void dfll_clk_disable(struct clk_hw *hw) { struct tegra_dfll *td = clk_hw_to_dfll(hw); int ret; ret = dfll_unlock(td); if (!ret) dfll_disable(td); }

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static unsigned long dfll_clk_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) { struct tegra_dfll *td = clk_hw_to_dfll(hw); return td->last_unrounded_rate; }

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/* Must use determine_rate since it allows for rates exceeding 2^31-1 */
static int dfll_clk_determine_rate(struct clk_hw *hw, struct clk_rate_request *clk_req) { struct tegra_dfll *td = clk_hw_to_dfll(hw); struct dfll_rate_req req; int ret; ret = dfll_calculate_rate_request(td, &req, clk_req->rate); if (ret) return ret; /* * Don't set the rounded rate, since it doesn't really matter as * the output rate will be voltage controlled anyway, and cpufreq * freaks out if any rounding happens. */ return 0; }

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static int dfll_clk_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long parent_rate) { struct tegra_dfll *td = clk_hw_to_dfll(hw); return dfll_request_rate(td, rate); }

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static const struct clk_ops dfll_clk_ops = { .is_enabled = dfll_clk_is_enabled, .enable = dfll_clk_enable, .disable = dfll_clk_disable, .recalc_rate = dfll_clk_recalc_rate, .determine_rate = dfll_clk_determine_rate, .set_rate = dfll_clk_set_rate, }; static struct clk_init_data dfll_clk_init_data = { .ops = &dfll_clk_ops, .num_parents = 0, }; /** * dfll_register_clk - register the DFLL output clock with the clock framework * @td: DFLL instance * * Register the DFLL's output clock with the Linux clock framework and register * the DFLL driver as an OF clock provider. Returns 0 upon success or -EINVAL * or -ENOMEM upon failure. */
static int dfll_register_clk(struct tegra_dfll *td) { int ret; dfll_clk_init_data.name = td->output_clock_name; td->dfll_clk_hw.init = &dfll_clk_init_data; td->dfll_clk = clk_register(td->dev, &td->dfll_clk_hw); if (IS_ERR(td->dfll_clk)) { dev_err(td->dev, "DFLL clock registration error\n"); return -EINVAL; } ret = of_clk_add_provider(td->dev->of_node, of_clk_src_simple_get, td->dfll_clk); if (ret) { dev_err(td->dev, "of_clk_add_provider() failed\n"); clk_unregister(td->dfll_clk); return ret; } return 0; }

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/** * dfll_unregister_clk - unregister the DFLL output clock * @td: DFLL instance * * Unregister the DFLL's output clock from the Linux clock framework * and from clkdev. No return value. */
static void dfll_unregister_clk(struct tegra_dfll *td) { of_clk_del_provider(td->dev->of_node); clk_unregister(td->dfll_clk); td->dfll_clk = NULL; }

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/* * Debugfs interface */ #ifdef CONFIG_DEBUG_FS /* * Monitor control */ /** * dfll_calc_monitored_rate - convert DFLL_MONITOR_DATA_VAL rate into real freq * @monitor_data: value read from the DFLL_MONITOR_DATA_VAL bitfield * @ref_rate: DFLL reference clock rate * * Convert @monitor_data from DFLL_MONITOR_DATA_VAL units into cycles * per second. Returns the converted value. */
static u64 dfll_calc_monitored_rate(u32 monitor_data, unsigned long ref_rate) { return monitor_data * (ref_rate / REF_CLK_CYC_PER_DVCO_SAMPLE); }

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/** * dfll_read_monitor_rate - return the DFLL's output rate from internal monitor * @td: DFLL instance * * If the DFLL is enabled, return the last rate reported by the DFLL's * internal monitoring hardware. This works in both open-loop and * closed-loop mode, and takes the output scaler setting into account. * Assumes that the monitor was programmed to monitor frequency before * the sample period started. If the driver believes that the DFLL is * currently uninitialized or disabled, it will return 0, since * otherwise the DFLL monitor data register will return the last * measured rate from when the DFLL was active. */
static u64 dfll_read_monitor_rate(struct tegra_dfll *td) { u32 v, s; u64 pre_scaler_rate, post_scaler_rate; if (!dfll_is_running(td)) return 0; v = dfll_readl(td, DFLL_MONITOR_DATA); v = (v & DFLL_MONITOR_DATA_VAL_MASK) >> DFLL_MONITOR_DATA_VAL_SHIFT; pre_scaler_rate = dfll_calc_monitored_rate(v, td->ref_rate); s = dfll_readl(td, DFLL_FREQ_REQ); s = (s & DFLL_FREQ_REQ_SCALE_MASK) >> DFLL_FREQ_REQ_SCALE_SHIFT; post_scaler_rate = dfll_scale_dvco_rate(s, pre_scaler_rate); return post_scaler_rate; }

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static int attr_enable_get(void *data, u64 *val) { struct tegra_dfll *td = data; *val = dfll_is_running(td); return 0; }

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static int attr_enable_set(void *data, u64 val) { struct tegra_dfll *td = data; return val ? dfll_enable(td) : dfll_disable(td); }

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DEFINE_SIMPLE_ATTRIBUTE(enable_fops, attr_enable_get, attr_enable_set, "%llu\n");
static int attr_lock_get(void *data, u64 *val) { struct tegra_dfll *td = data; *val = (td->mode == DFLL_CLOSED_LOOP); return 0; }

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static int attr_lock_set(void *data, u64 val) { struct tegra_dfll *td = data; return val ? dfll_lock(td) : dfll_unlock(td); }

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DEFINE_SIMPLE_ATTRIBUTE(lock_fops, attr_lock_get, attr_lock_set, "%llu\n");
static int attr_rate_get(void *data, u64 *val) { struct tegra_dfll *td = data; *val = dfll_read_monitor_rate(td); return 0; }

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static int attr_rate_set(void *data, u64 val) { struct tegra_dfll *td = data; return dfll_request_rate(td, val); }

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DEFINE_SIMPLE_ATTRIBUTE(rate_fops, attr_rate_get, attr_rate_set, "%llu\n");
static int attr_registers_show(struct seq_file *s, void *data) { u32 val, offs; struct tegra_dfll *td = s->private; seq_puts(s, "CONTROL REGISTERS:\n"); for (offs = 0; offs <= DFLL_MONITOR_DATA; offs += 4) { if (offs == DFLL_OUTPUT_CFG) val = dfll_i2c_readl(td, offs); else val = dfll_readl(td, offs); seq_printf(s, "[0x%02x] = 0x%08x\n", offs, val); } seq_puts(s, "\nI2C and INTR REGISTERS:\n"); for (offs = DFLL_I2C_CFG; offs <= DFLL_I2C_STS; offs += 4) seq_printf(s, "[0x%02x] = 0x%08x\n", offs, dfll_i2c_readl(td, offs)); for (offs = DFLL_INTR_STS; offs <= DFLL_INTR_EN; offs += 4) seq_printf(s, "[0x%02x] = 0x%08x\n", offs, dfll_i2c_readl(td, offs)); seq_puts(s, "\nINTEGRATED I2C CONTROLLER REGISTERS:\n"); offs = DFLL_I2C_CLK_DIVISOR; seq_printf(s, "[0x%02x] = 0x%08x\n", offs, __raw_readl(td->i2c_controller_base + offs)); seq_puts(s, "\nLUT:\n"); for (offs = 0; offs < 4 * MAX_DFLL_VOLTAGES; offs += 4) seq_printf(s, "[0x%02x] = 0x%08x\n", offs, __raw_readl(td->lut_base + offs)); return 0; }

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static int attr_registers_open(struct inode *inode, struct file *file) { return single_open(file, attr_registers_show, inode->i_private); }

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static const struct file_operations attr_registers_fops = { .open = attr_registers_open, .read = seq_read, .llseek = seq_lseek, .release = single_release, };
static int dfll_debug_init(struct tegra_dfll *td) { int ret; if (!td || (td->mode == DFLL_UNINITIALIZED)) return 0; td->debugfs_dir = debugfs_create_dir("tegra_dfll_fcpu", NULL); if (!td->debugfs_dir) return -ENOMEM; ret = -ENOMEM; if (!debugfs_create_file("enable", S_IRUGO | S_IWUSR, td->debugfs_dir, td, &enable_fops)) goto err_out; if (!debugfs_create_file("lock", S_IRUGO, td->debugfs_dir, td, &lock_fops)) goto err_out; if (!debugfs_create_file("rate", S_IRUGO, td->debugfs_dir, td, &rate_fops)) goto err_out; if (!debugfs_create_file("registers", S_IRUGO, td->debugfs_dir, td, &attr_registers_fops)) goto err_out; return 0; err_out: debugfs_remove_recursive(td->debugfs_dir); return ret; }

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#endif /* CONFIG_DEBUG_FS */ /* * DFLL initialization */ /** * dfll_set_default_params - program non-output related DFLL parameters * @td: DFLL instance * * During DFLL driver initialization or resume from context loss, * program parameters for the closed loop integrator, DVCO tuning, * voltage droop control and monitor control. */
static void dfll_set_default_params(struct tegra_dfll *td) { u32 val; val = DIV_ROUND_UP(td->ref_rate, td->sample_rate * 32); BUG_ON(val > DFLL_CONFIG_DIV_MASK); dfll_writel(td, val, DFLL_CONFIG); val = (td->force_mode << DFLL_PARAMS_FORCE_MODE_SHIFT) | (td->cf << DFLL_PARAMS_CF_PARAM_SHIFT) | (td->ci << DFLL_PARAMS_CI_PARAM_SHIFT) | (td->cg << DFLL_PARAMS_CG_PARAM_SHIFT) | (td->cg_scale ? DFLL_PARAMS_CG_SCALE : 0); dfll_writel(td, val, DFLL_PARAMS); dfll_tune_low(td); dfll_writel(td, td->droop_ctrl, DFLL_DROOP_CTRL); dfll_writel(td, DFLL_MONITOR_CTRL_FREQ, DFLL_MONITOR_CTRL); }

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/** * dfll_init_clks - clk_get() the DFLL source clocks * @td: DFLL instance * * Call clk_get() on the DFLL source clocks and save the pointers for later * use. Returns 0 upon success or error (see devm_clk_get) if one or more * of the clocks couldn't be looked up. */
static int dfll_init_clks(struct tegra_dfll *td) { td->ref_clk = devm_clk_get(td->dev, "ref"); if (IS_ERR(td->ref_clk)) { dev_err(td->dev, "missing ref clock\n"); return PTR_ERR(td->ref_clk); } td->soc_clk = devm_clk_get(td->dev, "soc"); if (IS_ERR(td->soc_clk)) { dev_err(td->dev, "missing soc clock\n"); return PTR_ERR(td->soc_clk); } td->i2c_clk = devm_clk_get(td->dev, "i2c"); if (IS_ERR(td->i2c_clk)) { dev_err(td->dev, "missing i2c clock\n"); return PTR_ERR(td->i2c_clk); } td->i2c_clk_rate = clk_get_rate(td->i2c_clk); return 0; }

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/** * dfll_init - Prepare the DFLL IP block for use * @td: DFLL instance * * Do everything necessary to prepare the DFLL IP block for use. The * DFLL will be left in DISABLED state. Called by dfll_probe(). * Returns 0 upon success, or passes along the error from whatever * function returned it. */
static int dfll_init(struct tegra_dfll *td) { int ret; td->ref_rate = clk_get_rate(td->ref_clk); if (td->ref_rate != REF_CLOCK_RATE) { dev_err(td->dev, "unexpected ref clk rate %lu, expecting %lu", td->ref_rate, REF_CLOCK_RATE); return -EINVAL; } reset_control_deassert(td->dvco_rst); ret = clk_prepare(td->ref_clk); if (ret) { dev_err(td->dev, "failed to prepare ref_clk\n"); return ret; } ret = clk_prepare(td->soc_clk); if (ret) { dev_err(td->dev, "failed to prepare soc_clk\n"); goto di_err1; } ret = clk_prepare(td->i2c_clk); if (ret) { dev_err(td->dev, "failed to prepare i2c_clk\n"); goto di_err2; } td->last_unrounded_rate = 0; pm_runtime_enable(td->dev); pm_runtime_get_sync(td->dev); dfll_set_mode(td, DFLL_DISABLED); dfll_set_default_params(td); if (td->soc->init_clock_trimmers) td->soc->init_clock_trimmers(); dfll_set_open_loop_config(td); dfll_init_out_if(td); pm_runtime_put_sync(td->dev); return 0; di_err2: clk_unprepare(td->soc_clk); di_err1: clk_unprepare(td->ref_clk); reset_control_assert(td->dvco_rst); return ret; }

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/* * DT data fetch */ /* * Find a PMIC voltage register-to-voltage mapping for the given voltage. * An exact voltage match is required. */
static int find_vdd_map_entry_exact(struct tegra_dfll *td, int uV) { int i, n_voltages, reg_uV; n_voltages = regulator_count_voltages(td->vdd_reg); for (i = 0; i < n_voltages; i++) { reg_uV = regulator_list_voltage(td->vdd_reg, i); if (reg_uV < 0) break; if (uV == reg_uV) return i; } dev_err(td->dev, "no voltage map entry for %d uV\n", uV); return -EINVAL; }

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/* * Find a PMIC voltage register-to-voltage mapping for the given voltage, * rounding up to the closest supported voltage. * */
static int find_vdd_map_entry_min(struct tegra_dfll *td, int uV) { int i, n_voltages, reg_uV; n_voltages = regulator_count_voltages(td->vdd_reg); for (i = 0; i < n_voltages; i++) { reg_uV = regulator_list_voltage(td->vdd_reg, i); if (reg_uV < 0) break; if (uV <= reg_uV) return i; } dev_err(td->dev, "no voltage map entry rounding to %d uV\n", uV); return -EINVAL; }

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/** * dfll_build_i2c_lut - build the I2C voltage register lookup table * @td: DFLL instance * * The DFLL hardware has 33 bytes of look-up table RAM that must be filled with * PMIC voltage register values that span the entire DFLL operating range. * This function builds the look-up table based on the OPP table provided by * the soc-specific platform driver (td->soc->opp_dev) and the PMIC * register-to-voltage mapping queried from the regulator framework. * * On success, fills in td->i2c_lut and returns 0, or -err on failure. */
static int dfll_build_i2c_lut(struct tegra_dfll *td) { int ret = -EINVAL; int j, v, v_max, v_opp; int selector; unsigned long rate; struct dev_pm_opp *opp; int lut; rcu_read_lock(); rate = ULONG_MAX; opp = dev_pm_opp_find_freq_floor(td->soc->dev, &rate); if (IS_ERR(opp)) { dev_err(td->dev, "couldn't get vmax opp, empty opp table?\n"); goto out; } v_max = dev_pm_opp_get_voltage(opp); v = td->soc->cvb->min_millivolts * 1000; lut = find_vdd_map_entry_exact(td, v); if (lut < 0) goto out; td->i2c_lut[0] = lut; for (j = 1, rate = 0; ; rate++) { opp = dev_pm_opp_find_freq_ceil(td->soc->dev, &rate); if (IS_ERR(opp)) break; v_opp = dev_pm_opp_get_voltage(opp); if (v_opp <= td->soc->cvb->min_millivolts * 1000) td->dvco_rate_min = dev_pm_opp_get_freq(opp); for (;;) { v += max(1, (v_max - v) / (MAX_DFLL_VOLTAGES - j)); if (v >= v_opp) break; selector = find_vdd_map_entry_min(td, v); if (selector < 0) goto out; if (selector != td->i2c_lut[j - 1]) td->i2c_lut[j++] = selector; } v = (j == MAX_DFLL_VOLTAGES - 1) ? v_max : v_opp; selector = find_vdd_map_entry_exact(td, v); if (selector < 0) goto out; if (selector != td->i2c_lut[j - 1]) td->i2c_lut[j++] = selector; if (v >= v_max) break; } td->i2c_lut_size = j; if (!td->dvco_rate_min) dev_err(td->dev, "no opp above DFLL minimum voltage %d mV\n", td->soc->cvb->min_millivolts); else ret = 0; out: rcu_read_unlock(); return ret; }

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/** * read_dt_param - helper function for reading required parameters from the DT * @td: DFLL instance * @param: DT property name * @dest: output pointer for the value read * * Read a required numeric parameter from the DFLL device node, or complain * if the property doesn't exist. Returns a boolean indicating success for * easy chaining of multiple calls to this function. */
static bool read_dt_param(struct tegra_dfll *td, const char *param, u32 *dest) { int err = of_property_read_u32(td->dev->of_node, param, dest); if (err < 0) { dev_err(td->dev, "failed to read DT parameter %s: %d\n", param, err); return false; } return true; }

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tuomas tynkkynentuomas tynkkynen63100.00%1100.00%
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/** * dfll_fetch_i2c_params - query PMIC I2C params from DT & regulator subsystem * @td: DFLL instance * * Read all the parameters required for operation in I2C mode. The parameters * can originate from the device tree or the regulator subsystem. * Returns 0 on success or -err on failure. */
static int dfll_fetch_i2c_params(struct tegra_dfll *td) { struct regmap *regmap; struct device *i2c_dev; struct i2c_client *i2c_client; int vsel_reg, vsel_mask; int ret; if (!read_dt_param(td, "nvidia,i2c-fs-rate", &td->i2c_fs_rate)) return -EINVAL; regmap = regulator_get_regmap(td->vdd_reg); i2c_dev = regmap_get_device(regmap); i2c_client = to_i2c_client(i2c_dev); td->i2c_slave_addr = i2c_client->addr; ret = regulator_get_hardware_vsel_register(td->vdd_reg, &vsel_reg, &vsel_mask); if (ret < 0) { dev_err(td->dev, "regulator unsuitable for DFLL I2C operation\n"); return -EINVAL; } td->i2c_reg = vsel_reg; ret = dfll_build_i2c_lut(td); if (ret) { dev_err(td->dev, "couldn't build I2C LUT\n"); return ret; } return 0; }

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tuomas tynkkynentuomas tynkkynen154100.00%1100.00%
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/** * dfll_fetch_common_params - read DFLL parameters from the device tree * @td: DFLL instance * * Read all the DT parameters that are common to both I2C and PWM operation. * Returns 0 on success or -EINVAL on any failure. */
static int dfll_fetch_common_params(struct tegra_dfll *td) { bool ok = true; ok &= read_dt_param(td, "nvidia,droop-ctrl", &td->droop_ctrl); ok &= read_dt_param(td, "nvidia,sample-rate", &td->sample_rate); ok &= read_dt_param(td, "nvidia,force-mode", &td->force_mode); ok &= read_dt_param(td, "nvidia,cf", &td->cf); ok &= read_dt_param(td, "nvidia,ci", &td->ci); ok &= read_dt_param(td, "nvidia,cg", &td->cg); td->cg_scale = of_property_read_bool(td->dev->of_node, "nvidia,cg-scale"); if (of_property_read_string(td->dev->of_node, "clock-output-names", &td->output_clock_name)) { dev_err(td->dev, "missing clock-output-names property\n"); ok = false; } return ok ? 0 : -EINVAL; }

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tuomas tynkkynentuomas tynkkynen156100.00%2100.00%
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/* * API exported to per-SoC platform drivers */ /** * tegra_dfll_register - probe a Tegra DFLL device * @pdev: DFLL platform_device * * @soc: Per-SoC integration and characterization data for this DFLL instance * * Probe and initialize a DFLL device instance. Intended to be called * by a SoC-specific shim driver that passes in per-SoC integration * and configuration data via @soc. Returns 0 on success or -err on failure. */
int tegra_dfll_register(struct platform_device *pdev, struct tegra_dfll_soc_data *soc) { struct resource *mem; struct tegra_dfll *td; int ret; if (!soc) { dev_err(&pdev->dev, "no tegra_dfll_soc_data provided\n"); return -EINVAL; } td = devm_kzalloc(&pdev->dev, sizeof(*td), GFP_KERNEL); if (!td) return -ENOMEM; td->dev = &pdev->dev; platform_set_drvdata(pdev, td); td->soc = soc; td->vdd_reg = devm_regulator_get(td->dev, "vdd-cpu"); if (IS_ERR(td->vdd_reg)) { dev_err(td->dev, "couldn't get vdd_cpu regulator\n"); return PTR_ERR(td->vdd_reg); } td->dvco_rst = devm_reset_control_get(td->dev, "dvco"); if (IS_ERR(td->dvco_rst)) { dev_err(td->dev, "couldn't get dvco reset\n"); return PTR_ERR(td->dvco_rst); } ret = dfll_fetch_common_params(td); if (ret) { dev_err(td->dev, "couldn't parse device tree parameters\n"); return ret; } ret = dfll_fetch_i2c_params(td); if (ret) return ret; mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!mem) { dev_err(td->dev, "no control register resource\n"); return -ENODEV; } td->base = devm_ioremap(td->dev, mem->start, resource_size(mem)); if (!td->base) { dev_err(td->dev, "couldn't ioremap DFLL control registers\n"); return -ENODEV; } mem = platform_get_resource(pdev, IORESOURCE_MEM, 1); if (!mem) { dev_err(td->dev, "no i2c_base resource\n"); return -ENODEV; } td->i2c_base = devm_ioremap(td->dev, mem->start, resource_size(mem)); if (!td->i2c_base) { dev_err(td->dev, "couldn't ioremap i2c_base resource\n"); return -ENODEV; } mem = platform_get_resource(pdev, IORESOURCE_MEM, 2); if (!mem) { dev_err(td->dev, "no i2c_controller_base resource\n"); return -ENODEV; } td->i2c_controller_base = devm_ioremap(td->dev, mem->start, resource_size(mem)); if (!td->i2c_controller_base) { dev_err(td->dev, "couldn't ioremap i2c_controller_base resource\n"); return -ENODEV; } mem = platform_get_resource(pdev, IORESOURCE_MEM, 3); if (!mem) { dev_err(td->dev, "no lut_base resource\n"); return -ENODEV; } td->lut_base = devm_ioremap(td->dev, mem->start, resource_size(mem)); if (!td->lut_base) { dev_err(td->dev, "couldn't ioremap lut_base resource\n"); return -ENODEV; } ret = dfll_init_clks(td); if (ret) { dev_err(&pdev->dev, "DFLL clock init error\n"); return ret; } /* Enable the clocks and set the device up */ ret = dfll_init(td); if (ret) return ret; ret = dfll_register_clk(td); if (ret) { dev_err(&pdev->dev, "DFLL clk registration failed\n"); return ret; } #ifdef CONFIG_DEBUG_FS dfll_debug_init(td); #endif return 0; }

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EXPORT_SYMBOL(tegra_dfll_register); /** * tegra_dfll_unregister - release all of the DFLL driver resources for a device * @pdev: DFLL platform_device * * * Unbind this driver from the DFLL hardware device represented by * @pdev. The DFLL must be disabled for this to succeed. Returns 0 * upon success or -EBUSY if the DFLL is still active. */
int tegra_dfll_unregister(struct platform_device *pdev) { struct tegra_dfll *td = platform_get_drvdata(pdev); /* Try to prevent removal while the DFLL is active */ if (td->mode != DFLL_DISABLED) { dev_err(&pdev->dev, "must disable DFLL before removing driver\n"); return -EBUSY; } debugfs_remove_recursive(td->debugfs_dir); dfll_unregister_clk(td); pm_runtime_disable(&pdev->dev); clk_unprepare(td->ref_clk); clk_unprepare(td->soc_clk); clk_unprepare(td->i2c_clk); reset_control_assert(td->dvco_rst); return 0; }

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EXPORT_SYMBOL(tegra_dfll_unregister);

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stephen boydstephen boyd140.24%112.50%
mikko perttunenmikko perttunen120.20%112.50%
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