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linux/drivers/clk/tegra/clk-dfll.c
Sowjanya Komatineni d8edf5280c clk: tegra: clk-dfll: Remove call to pm_runtime_irq_safe() 
pm_runtime_irq_safe() is not needed as interrupts are allowed during
suspend and resume. This was added mistakenly during DFLL suspend and
resume support patch.

While at it, also update the description of the dev argument that is
passed to the tegra_dfll_suspend() function.

Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
2020-01-10 15:39:03 +01:00

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// SPDX-License-Identifier: GPL-2.0-only
/*
* clk-dfll.c - Tegra DFLL clock source common code
*
* Copyright (C) 2012-2019 NVIDIA Corporation. All rights reserved.
*
* Aleksandr Frid <afrid@nvidia.com>
* Paul Walmsley <pwalmsley@nvidia.com>
*
* 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/pinctrl/consumer.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,
};
enum tegra_dfll_pmu_if {
TEGRA_DFLL_PMU_I2C = 0,
TEGRA_DFLL_PMU_PWM = 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;
/* lut array entries are regulator framework selectors or PWM values*/
unsigned lut[MAX_DFLL_VOLTAGES];
unsigned long lut_uv[MAX_DFLL_VOLTAGES];
int lut_size;
u8 lut_bottom, lut_min, lut_max, lut_safe;
/* PWM interface */
enum tegra_dfll_pmu_if pmu_if;
unsigned long pwm_rate;
struct pinctrl *pwm_pin;
struct pinctrl_state *pwm_enable_state;
struct pinctrl_state *pwm_disable_state;
u32 reg_init_uV;
};
#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);
}
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);
}
static inline void dfll_wmb(struct tegra_dfll *td)
{
dfll_readl(td, DFLL_CTRL);
}
/* 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);
}
static inline void dfll_i2c_writel(struct tegra_dfll *td, u32 val, u32 offs)
{
__raw_writel(val, td->i2c_base + offs);
}
static inline void dfll_i2c_wmb(struct tegra_dfll *td)
{
dfll_i2c_readl(td, DFLL_I2C_CFG);
}
/**
* 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;
}
/*
* 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;
}
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;
}
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();
}
/*
* 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;
}
/*
* 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);
}
/*
* DVCO rate control
*/
static unsigned long get_dvco_rate_below(struct tegra_dfll *td, u8 out_min)
{
struct dev_pm_opp *opp;
unsigned long rate, prev_rate;
unsigned long uv, min_uv;
min_uv = td->lut_uv[out_min];
for (rate = 0, prev_rate = 0; ; rate++) {
opp = dev_pm_opp_find_freq_ceil(td->soc->dev, &rate);
if (IS_ERR(opp))
break;
uv = dev_pm_opp_get_voltage(opp);
dev_pm_opp_put(opp);
if (uv && uv > min_uv)
return prev_rate;
prev_rate = rate;
}
return prev_rate;
}
/*
* 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;
}
/*
* DFLL-to-PWM controller interface
*/
/**
* dfll_pwm_set_output_enabled - enable/disable PWM voltage requests
* @td: DFLL instance
* @enable: whether to enable or disable the PWM voltage requests
*
* Set the master enable control for PWM control value updates. If disabled,
* then the PWM signal is not driven. Also configure the PWM output pad
* to the appropriate state.
*/
static int dfll_pwm_set_output_enabled(struct tegra_dfll *td, bool enable)
{
int ret;
u32 val, div;
if (enable) {
ret = pinctrl_select_state(td->pwm_pin, td->pwm_enable_state);
if (ret < 0) {
dev_err(td->dev, "setting enable state failed\n");
return -EINVAL;
}
val = dfll_readl(td, DFLL_OUTPUT_CFG);
val &= ~DFLL_OUTPUT_CFG_PWM_DIV_MASK;
div = DIV_ROUND_UP(td->ref_rate, td->pwm_rate);
val |= (div << DFLL_OUTPUT_CFG_PWM_DIV_SHIFT)
& DFLL_OUTPUT_CFG_PWM_DIV_MASK;
dfll_writel(td, val, DFLL_OUTPUT_CFG);
dfll_wmb(td);
val |= DFLL_OUTPUT_CFG_PWM_ENABLE;
dfll_writel(td, val, DFLL_OUTPUT_CFG);
dfll_wmb(td);
} else {
ret = pinctrl_select_state(td->pwm_pin, td->pwm_disable_state);
if (ret < 0)
dev_warn(td->dev, "setting disable state failed\n");
val = dfll_readl(td, DFLL_OUTPUT_CFG);
val &= ~DFLL_OUTPUT_CFG_PWM_ENABLE;
dfll_writel(td, val, DFLL_OUTPUT_CFG);
dfll_wmb(td);
}
return 0;
}
/**
* dfll_set_force_output_value - set fixed value for force output
* @td: DFLL instance
* @out_val: value to force output
*
* Set the fixed value for force output, DFLL will output this value when
* force output is enabled.
*/
static u32 dfll_set_force_output_value(struct tegra_dfll *td, u8 out_val)
{
u32 val = dfll_readl(td, DFLL_OUTPUT_FORCE);
val = (val & DFLL_OUTPUT_FORCE_ENABLE) | (out_val & OUT_MASK);
dfll_writel(td, val, DFLL_OUTPUT_FORCE);
dfll_wmb(td);
return dfll_readl(td, DFLL_OUTPUT_FORCE);
}
/**
* dfll_set_force_output_enabled - enable/disable force output
* @td: DFLL instance
* @enable: whether to enable or disable the force output
*
* Set the enable control for fouce output with fixed value.
*/
static void dfll_set_force_output_enabled(struct tegra_dfll *td, bool enable)
{
u32 val = dfll_readl(td, DFLL_OUTPUT_FORCE);
if (enable)
val |= DFLL_OUTPUT_FORCE_ENABLE;
else
val &= ~DFLL_OUTPUT_FORCE_ENABLE;
dfll_writel(td, val, DFLL_OUTPUT_FORCE);
dfll_wmb(td);
}
/**
* dfll_force_output - force output a fixed value
* @td: DFLL instance
* @out_sel: value to force output
*
* Set the fixed value for force output, DFLL will output this value.
*/
static int dfll_force_output(struct tegra_dfll *td, unsigned int out_sel)
{
u32 val;
if (out_sel > OUT_MASK)
return -EINVAL;
val = dfll_set_force_output_value(td, out_sel);
if ((td->mode < DFLL_CLOSED_LOOP) &&
!(val & DFLL_OUTPUT_FORCE_ENABLE)) {
dfll_set_force_output_enabled(td, true);
}
return 0;
}
/**
* 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->lut[lut_index]);
__raw_writel(val, td->lut_base + i * 4);
}
dfll_i2c_wmb(td);
}
/**
* 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);
}
/**
* 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 = td->lut_bottom;
td->lut_max = td->lut_size - 1;
td->lut_safe = td->lut_min + (td->lut_min < td->lut_max ? 1 : 0);
/* clear DFLL_OUTPUT_CFG before setting new value */
dfll_writel(td, 0, DFLL_OUTPUT_CFG);
dfll_wmb(td);
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_writel(td, val, DFLL_OUTPUT_CFG);
dfll_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);
if (td->pmu_if == TEGRA_DFLL_PMU_PWM) {
u32 vinit = td->reg_init_uV;
int vstep = td->soc->alignment.step_uv;
unsigned long vmin = td->lut_uv[0];
/* set initial voltage */
if ((vinit >= vmin) && vstep) {
unsigned int vsel;
vsel = DIV_ROUND_UP((vinit - vmin), vstep);
dfll_force_output(td, vsel);
}
} else {
dfll_load_i2c_lut(td);
dfll_init_i2c_if(td);
}
}
/*
* 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, align_step;
opp = dev_pm_opp_find_freq_ceil(td->soc->dev, &rate);
if (IS_ERR(opp))
return PTR_ERR(opp);
align_step = dev_pm_opp_get_voltage(opp) / td->soc->alignment.step_uv;
dev_pm_opp_put(opp);
for (i = td->lut_bottom; i < td->lut_size; i++) {
if ((td->lut_uv[i] / td->soc->alignment.step_uv) >= align_step)
return i;
}
return -ENOENT;
}
/**
* 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;
}
/**
* 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);
}
/**
* 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;
}
/*
* 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;
}
/**
* 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;
}
/**
* 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);
}
/**
* 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;
}
if (td->pmu_if == TEGRA_DFLL_PMU_PWM)
dfll_pwm_set_output_enabled(td, true);
else
dfll_i2c_set_output_enabled(td, true);
dfll_set_mode(td, DFLL_CLOSED_LOOP);
dfll_set_frequency_request(td, req);
dfll_set_force_output_enabled(td, false);
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;
}
}
/**
* 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);
if (td->pmu_if == TEGRA_DFLL_PMU_PWM)
dfll_pwm_set_output_enabled(td, false);
else
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;
}
}
/*
* 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);
}
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;
}
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);
}
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;
}
/* 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;
}
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);
}
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;
}
/**
* 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;
}
/*
* 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);
}
/**
* 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;
}
static int attr_enable_get(void *data, u64 *val)
{
struct tegra_dfll *td = data;
*val = dfll_is_running(td);
return 0;
}
static int attr_enable_set(void *data, u64 val)
{
struct tegra_dfll *td = data;
return val ? dfll_enable(td) : dfll_disable(td);
}
DEFINE_DEBUGFS_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;
}
static int attr_lock_set(void *data, u64 val)
{
struct tegra_dfll *td = data;
return val ? dfll_lock(td) : dfll_unlock(td);
}
DEFINE_DEBUGFS_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;
}
static int attr_rate_set(void *data, u64 val)
{
struct tegra_dfll *td = data;
return dfll_request_rate(td, val);
}
DEFINE_DEBUGFS_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));
if (td->pmu_if == TEGRA_DFLL_PMU_I2C) {
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;
}
DEFINE_SHOW_ATTRIBUTE(attr_registers);
static void dfll_debug_init(struct tegra_dfll *td)
{
struct dentry *root;
if (!td || (td->mode == DFLL_UNINITIALIZED))
return;
root = debugfs_create_dir("tegra_dfll_fcpu", NULL);
td->debugfs_dir = root;
debugfs_create_file_unsafe("enable", 0644, root, td,
&enable_fops);
debugfs_create_file_unsafe("lock", 0444, root, td, &lock_fops);
debugfs_create_file_unsafe("rate", 0444, root, td, &rate_fops);
debugfs_create_file("registers", 0444, root, td, &attr_registers_fops);
}
#else
static void inline dfll_debug_init(struct tegra_dfll *td) { }
#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);
}
/**
* 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;
}
/**
* 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;
}
/**
* tegra_dfll_suspend - check DFLL is disabled
* @dev: DFLL instance
*
* DFLL clock should be disabled by the CPUFreq driver. So, make
* sure it is disabled and disable all clocks needed by the DFLL.
*/
int tegra_dfll_suspend(struct device *dev)
{
struct tegra_dfll *td = dev_get_drvdata(dev);
if (dfll_is_running(td)) {
dev_err(td->dev, "DFLL still enabled while suspending\n");
return -EBUSY;
}
reset_control_assert(td->dvco_rst);
return 0;
}
EXPORT_SYMBOL(tegra_dfll_suspend);
/**
* tegra_dfll_resume - reinitialize DFLL on resume
* @dev: DFLL instance
*
* DFLL is disabled and reset during suspend and resume.
* So, reinitialize the DFLL IP block back for use.
* DFLL clock is enabled later in closed loop mode by CPUFreq
* driver before switching its clock source to DFLL output.
*/
int tegra_dfll_resume(struct device *dev)
{
struct tegra_dfll *td = dev_get_drvdata(dev);
reset_control_deassert(td->dvco_rst);
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;
}
EXPORT_SYMBOL(tegra_dfll_resume);
/*
* 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,reg_volt_id, align_step;
if (WARN_ON(td->pmu_if == TEGRA_DFLL_PMU_PWM))
return -EINVAL;
align_step = uV / td->soc->alignment.step_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;
reg_volt_id = reg_uV / td->soc->alignment.step_uv;
if (align_step == reg_volt_id)
return i;
}
dev_err(td->dev, "no voltage map entry for %d uV\n", uV);
return -EINVAL;
}
/*
* 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, reg_volt_id, align_step;
if (WARN_ON(td->pmu_if == TEGRA_DFLL_PMU_PWM))
return -EINVAL;
align_step = uV / td->soc->alignment.step_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;
reg_volt_id = reg_uV / td->soc->alignment.step_uv;
if (align_step <= reg_volt_id)
return i;
}
dev_err(td->dev, "no voltage map entry rounding to %d uV\n", uV);
return -EINVAL;
}
/*
* dfll_build_pwm_lut - build the PWM regulator lookup table
* @td: DFLL instance
* @v_max: Vmax from OPP table
*
* Look-up table in h/w is ignored when PWM is used as DFLL interface to PMIC.
* In this case closed loop output is controlling duty cycle directly. The s/w
* look-up that maps PWM duty cycle to voltage is still built by this function.
*/
static int dfll_build_pwm_lut(struct tegra_dfll *td, unsigned long v_max)
{
int i;
unsigned long rate, reg_volt;
u8 lut_bottom = MAX_DFLL_VOLTAGES;
int v_min = td->soc->cvb->min_millivolts * 1000;
for (i = 0; i < MAX_DFLL_VOLTAGES; i++) {
reg_volt = td->lut_uv[i];
/* since opp voltage is exact mv */
reg_volt = (reg_volt / 1000) * 1000;
if (reg_volt > v_max)
break;
td->lut[i] = i;
if ((lut_bottom == MAX_DFLL_VOLTAGES) && (reg_volt >= v_min))
lut_bottom = i;
}
/* determine voltage boundaries */
td->lut_size = i;
if ((lut_bottom == MAX_DFLL_VOLTAGES) ||
(lut_bottom + 1 >= td->lut_size)) {
dev_err(td->dev, "no voltage above DFLL minimum %d mV\n",
td->soc->cvb->min_millivolts);
return -EINVAL;
}
td->lut_bottom = lut_bottom;
/* determine rate boundaries */
rate = get_dvco_rate_below(td, td->lut_bottom);
if (!rate) {
dev_err(td->dev, "no opp below DFLL minimum voltage %d mV\n",
td->soc->cvb->min_millivolts);
return -EINVAL;
}
td->dvco_rate_min = rate;
return 0;
}
/**
* dfll_build_i2c_lut - build the I2C voltage register lookup table
* @td: DFLL instance
* @v_max: Vmax from OPP table
*
* 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->lut and returns 0, or -err on failure.
*/
static int dfll_build_i2c_lut(struct tegra_dfll *td, unsigned long v_max)
{
unsigned long rate, v, v_opp;
int ret = -EINVAL;
int j, selector, lut;
v = td->soc->cvb->min_millivolts * 1000;
lut = find_vdd_map_entry_exact(td, v);
if (lut < 0)
goto out;
td->lut[0] = lut;
td->lut_bottom = 0;
for (j = 1, rate = 0; ; rate++) {
struct dev_pm_opp *opp;
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);
dev_pm_opp_put(opp);
for (;;) {
v += max(1UL, (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->lut[j - 1])
td->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->lut[j - 1])
td->lut[j++] = selector;
if (v >= v_max)
break;
}
td->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;
for (j = 0; j < td->lut_size; j++)
td->lut_uv[j] =
regulator_list_voltage(td->vdd_reg,
td->lut[j]);
}
out:
return ret;
}
static int dfll_build_lut(struct tegra_dfll *td)
{
unsigned long rate, v_max;
struct dev_pm_opp *opp;
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");
return -EINVAL;
}
v_max = dev_pm_opp_get_voltage(opp);
dev_pm_opp_put(opp);
if (td->pmu_if == TEGRA_DFLL_PMU_PWM)
return dfll_build_pwm_lut(td, v_max);
else
return dfll_build_i2c_lut(td, v_max);
}
/**
* 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;
}
/**
* 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;
return 0;
}
static int dfll_fetch_pwm_params(struct tegra_dfll *td)
{
int ret, i;
u32 pwm_period;
if (!td->soc->alignment.step_uv || !td->soc->alignment.offset_uv) {
dev_err(td->dev,
"Missing step or alignment info for PWM regulator");
return -EINVAL;
}
for (i = 0; i < MAX_DFLL_VOLTAGES; i++)
td->lut_uv[i] = td->soc->alignment.offset_uv +
i * td->soc->alignment.step_uv;
ret = read_dt_param(td, "nvidia,pwm-tristate-microvolts",
&td->reg_init_uV);
if (!ret) {
dev_err(td->dev, "couldn't get initialized voltage\n");
return ret;
}
ret = read_dt_param(td, "nvidia,pwm-period-nanoseconds", &pwm_period);
if (!ret) {
dev_err(td->dev, "couldn't get PWM period\n");
return ret;
}
td->pwm_rate = (NSEC_PER_SEC / pwm_period) * (MAX_DFLL_VOLTAGES - 1);
td->pwm_pin = devm_pinctrl_get(td->dev);
if (IS_ERR(td->pwm_pin)) {
dev_err(td->dev, "DT: missing pinctrl device\n");
return PTR_ERR(td->pwm_pin);
}
td->pwm_enable_state = pinctrl_lookup_state(td->pwm_pin,
"dvfs_pwm_enable");
if (IS_ERR(td->pwm_enable_state)) {
dev_err(td->dev, "DT: missing pwm enabled state\n");
return PTR_ERR(td->pwm_enable_state);
}
td->pwm_disable_state = pinctrl_lookup_state(td->pwm_pin,
"dvfs_pwm_disable");
if (IS_ERR(td->pwm_disable_state)) {
dev_err(td->dev, "DT: missing pwm disabled state\n");
return PTR_ERR(td->pwm_disable_state);
}
return 0;
}
/**
* 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;
}
/*
* 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->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;
}
if (of_property_read_bool(td->dev->of_node, "nvidia,pwm-to-pmic")) {
td->pmu_if = TEGRA_DFLL_PMU_PWM;
ret = dfll_fetch_pwm_params(td);
} else {
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->pmu_if = TEGRA_DFLL_PMU_I2C;
ret = dfll_fetch_i2c_params(td);
}
if (ret)
return ret;
ret = dfll_build_lut(td);
if (ret) {
dev_err(td->dev, "couldn't build LUT\n");
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;
}
dfll_debug_init(td);
return 0;
}
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 a
* soc pointer upon success or -EBUSY if the DFLL is still active.
*/
struct tegra_dfll_soc_data *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 ERR_PTR(-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 td->soc;
}
EXPORT_SYMBOL(tegra_dfll_unregister);
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