blob: 39367712ef540ab62ff6c21329a2cd7f111e32b3 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* Xilinx 'Clocking Wizard' driver
*
* Copyright (C) 2013 - 2014 Xilinx
*
* Sören Brinkmann <soren.brinkmann@xilinx.com>
*/
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/module.h>
#include <linux/err.h>
#include <linux/iopoll.h>
#define WZRD_NUM_OUTPUTS 7
#define WZRD_ACLK_MAX_FREQ 250000000UL
#define WZRD_CLK_CFG_REG(n) (0x200 + 4 * (n))
#define WZRD_CLKOUT0_FRAC_EN BIT(18)
#define WZRD_CLKFBOUT_FRAC_EN BIT(26)
#define WZRD_CLKFBOUT_MULT_SHIFT 8
#define WZRD_CLKFBOUT_MULT_MASK (0xff << WZRD_CLKFBOUT_MULT_SHIFT)
#define WZRD_CLKFBOUT_FRAC_SHIFT 16
#define WZRD_CLKFBOUT_FRAC_MASK (0x3ff << WZRD_CLKFBOUT_FRAC_SHIFT)
#define WZRD_DIVCLK_DIVIDE_SHIFT 0
#define WZRD_DIVCLK_DIVIDE_MASK (0xff << WZRD_DIVCLK_DIVIDE_SHIFT)
#define WZRD_CLKOUT_DIVIDE_SHIFT 0
#define WZRD_CLKOUT_DIVIDE_WIDTH 8
#define WZRD_CLKOUT_DIVIDE_MASK (0xff << WZRD_DIVCLK_DIVIDE_SHIFT)
#define WZRD_CLKOUT_FRAC_SHIFT 8
#define WZRD_CLKOUT_FRAC_MASK 0x3ff
#define WZRD_DR_MAX_INT_DIV_VALUE 255
#define WZRD_DR_STATUS_REG_OFFSET 0x04
#define WZRD_DR_LOCK_BIT_MASK 0x00000001
#define WZRD_DR_INIT_REG_OFFSET 0x25C
#define WZRD_DR_DIV_TO_PHASE_OFFSET 4
#define WZRD_DR_BEGIN_DYNA_RECONF 0x03
#define WZRD_USEC_POLL 10
#define WZRD_TIMEOUT_POLL 1000
/* Get the mask from width */
#define div_mask(width) ((1 << (width)) - 1)
/* Extract divider instance from clock hardware instance */
#define to_clk_wzrd_divider(_hw) container_of(_hw, struct clk_wzrd_divider, hw)
enum clk_wzrd_int_clks {
wzrd_clk_mul,
wzrd_clk_mul_div,
wzrd_clk_mul_frac,
wzrd_clk_int_max
};
/**
* struct clk_wzrd - Clock wizard private data structure
*
* @clk_data: Clock data
* @nb: Notifier block
* @base: Memory base
* @clk_in1: Handle to input clock 'clk_in1'
* @axi_clk: Handle to input clock 's_axi_aclk'
* @clks_internal: Internal clocks
* @clkout: Output clocks
* @speed_grade: Speed grade of the device
* @suspended: Flag indicating power state of the device
*/
struct clk_wzrd {
struct clk_onecell_data clk_data;
struct notifier_block nb;
void __iomem *base;
struct clk *clk_in1;
struct clk *axi_clk;
struct clk *clks_internal[wzrd_clk_int_max];
struct clk *clkout[WZRD_NUM_OUTPUTS];
unsigned int speed_grade;
bool suspended;
};
/**
* struct clk_wzrd_divider - clock divider specific to clk_wzrd
*
* @hw: handle between common and hardware-specific interfaces
* @base: base address of register containing the divider
* @offset: offset address of register containing the divider
* @shift: shift to the divider bit field
* @width: width of the divider bit field
* @flags: clk_wzrd divider flags
* @table: array of value/divider pairs, last entry should have div = 0
* @lock: register lock
*/
struct clk_wzrd_divider {
struct clk_hw hw;
void __iomem *base;
u16 offset;
u8 shift;
u8 width;
u8 flags;
const struct clk_div_table *table;
spinlock_t *lock; /* divider lock */
};
#define to_clk_wzrd(_nb) container_of(_nb, struct clk_wzrd, nb)
/* maximum frequencies for input/output clocks per speed grade */
static const unsigned long clk_wzrd_max_freq[] = {
800000000UL,
933000000UL,
1066000000UL
};
/* spin lock variable for clk_wzrd */
static DEFINE_SPINLOCK(clkwzrd_lock);
static unsigned long clk_wzrd_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct clk_wzrd_divider *divider = to_clk_wzrd_divider(hw);
void __iomem *div_addr = divider->base + divider->offset;
unsigned int val;
val = readl(div_addr) >> divider->shift;
val &= div_mask(divider->width);
return divider_recalc_rate(hw, parent_rate, val, divider->table,
divider->flags, divider->width);
}
static int clk_wzrd_dynamic_reconfig(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
int err;
u32 value;
unsigned long flags = 0;
struct clk_wzrd_divider *divider = to_clk_wzrd_divider(hw);
void __iomem *div_addr = divider->base + divider->offset;
if (divider->lock)
spin_lock_irqsave(divider->lock, flags);
else
__acquire(divider->lock);
value = DIV_ROUND_CLOSEST(parent_rate, rate);
/* Cap the value to max */
min_t(u32, value, WZRD_DR_MAX_INT_DIV_VALUE);
/* Set divisor and clear phase offset */
writel(value, div_addr);
writel(0x00, div_addr + WZRD_DR_DIV_TO_PHASE_OFFSET);
/* Check status register */
err = readl_poll_timeout(divider->base + WZRD_DR_STATUS_REG_OFFSET,
value, value & WZRD_DR_LOCK_BIT_MASK,
WZRD_USEC_POLL, WZRD_TIMEOUT_POLL);
if (err)
goto err_reconfig;
/* Initiate reconfiguration */
writel(WZRD_DR_BEGIN_DYNA_RECONF,
divider->base + WZRD_DR_INIT_REG_OFFSET);
/* Check status register */
err = readl_poll_timeout(divider->base + WZRD_DR_STATUS_REG_OFFSET,
value, value & WZRD_DR_LOCK_BIT_MASK,
WZRD_USEC_POLL, WZRD_TIMEOUT_POLL);
err_reconfig:
if (divider->lock)
spin_unlock_irqrestore(divider->lock, flags);
else
__release(divider->lock);
return err;
}
static long clk_wzrd_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *prate)
{
u8 div;
/*
* since we don't change parent rate we just round rate to closest
* achievable
*/
div = DIV_ROUND_CLOSEST(*prate, rate);
return *prate / div;
}
static const struct clk_ops clk_wzrd_clk_divider_ops = {
.round_rate = clk_wzrd_round_rate,
.set_rate = clk_wzrd_dynamic_reconfig,
.recalc_rate = clk_wzrd_recalc_rate,
};
static unsigned long clk_wzrd_recalc_ratef(struct clk_hw *hw,
unsigned long parent_rate)
{
unsigned int val;
u32 div, frac;
struct clk_wzrd_divider *divider = to_clk_wzrd_divider(hw);
void __iomem *div_addr = divider->base + divider->offset;
val = readl(div_addr);
div = val & div_mask(divider->width);
frac = (val >> WZRD_CLKOUT_FRAC_SHIFT) & WZRD_CLKOUT_FRAC_MASK;
return mult_frac(parent_rate, 1000, (div * 1000) + frac);
}
static int clk_wzrd_dynamic_reconfig_f(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
int err;
u32 value, pre;
unsigned long rate_div, f, clockout0_div;
struct clk_wzrd_divider *divider = to_clk_wzrd_divider(hw);
void __iomem *div_addr = divider->base + divider->offset;
rate_div = ((parent_rate * 1000) / rate);
clockout0_div = rate_div / 1000;
pre = DIV_ROUND_CLOSEST((parent_rate * 1000), rate);
f = (u32)(pre - (clockout0_div * 1000));
f = f & WZRD_CLKOUT_FRAC_MASK;
f = f << WZRD_CLKOUT_DIVIDE_WIDTH;
value = (f | (clockout0_div & WZRD_CLKOUT_DIVIDE_MASK));
/* Set divisor and clear phase offset */
writel(value, div_addr);
writel(0x0, div_addr + WZRD_DR_DIV_TO_PHASE_OFFSET);
/* Check status register */
err = readl_poll_timeout(divider->base + WZRD_DR_STATUS_REG_OFFSET, value,
value & WZRD_DR_LOCK_BIT_MASK,
WZRD_USEC_POLL, WZRD_TIMEOUT_POLL);
if (err)
return err;
/* Initiate reconfiguration */
writel(WZRD_DR_BEGIN_DYNA_RECONF,
divider->base + WZRD_DR_INIT_REG_OFFSET);
/* Check status register */
return readl_poll_timeout(divider->base + WZRD_DR_STATUS_REG_OFFSET, value,
value & WZRD_DR_LOCK_BIT_MASK,
WZRD_USEC_POLL, WZRD_TIMEOUT_POLL);
}
static long clk_wzrd_round_rate_f(struct clk_hw *hw, unsigned long rate,
unsigned long *prate)
{
return rate;
}
static const struct clk_ops clk_wzrd_clk_divider_ops_f = {
.round_rate = clk_wzrd_round_rate_f,
.set_rate = clk_wzrd_dynamic_reconfig_f,
.recalc_rate = clk_wzrd_recalc_ratef,
};
static struct clk *clk_wzrd_register_divf(struct device *dev,
const char *name,
const char *parent_name,
unsigned long flags,
void __iomem *base, u16 offset,
u8 shift, u8 width,
u8 clk_divider_flags,
const struct clk_div_table *table,
spinlock_t *lock)
{
struct clk_wzrd_divider *div;
struct clk_hw *hw;
struct clk_init_data init;
int ret;
div = devm_kzalloc(dev, sizeof(*div), GFP_KERNEL);
if (!div)
return ERR_PTR(-ENOMEM);
init.name = name;
init.ops = &clk_wzrd_clk_divider_ops_f;
init.flags = flags;
init.parent_names = &parent_name;
init.num_parents = 1;
div->base = base;
div->offset = offset;
div->shift = shift;
div->width = width;
div->flags = clk_divider_flags;
div->lock = lock;
div->hw.init = &init;
div->table = table;
hw = &div->hw;
ret = devm_clk_hw_register(dev, hw);
if (ret)
return ERR_PTR(ret);
return hw->clk;
}
static struct clk *clk_wzrd_register_divider(struct device *dev,
const char *name,
const char *parent_name,
unsigned long flags,
void __iomem *base, u16 offset,
u8 shift, u8 width,
u8 clk_divider_flags,
const struct clk_div_table *table,
spinlock_t *lock)
{
struct clk_wzrd_divider *div;
struct clk_hw *hw;
struct clk_init_data init;
int ret;
div = devm_kzalloc(dev, sizeof(*div), GFP_KERNEL);
if (!div)
return ERR_PTR(-ENOMEM);
init.name = name;
init.ops = &clk_wzrd_clk_divider_ops;
init.flags = flags;
init.parent_names = &parent_name;
init.num_parents = 1;
div->base = base;
div->offset = offset;
div->shift = shift;
div->width = width;
div->flags = clk_divider_flags;
div->lock = lock;
div->hw.init = &init;
div->table = table;
hw = &div->hw;
ret = devm_clk_hw_register(dev, hw);
if (ret)
hw = ERR_PTR(ret);
return hw->clk;
}
static int clk_wzrd_clk_notifier(struct notifier_block *nb, unsigned long event,
void *data)
{
unsigned long max;
struct clk_notifier_data *ndata = data;
struct clk_wzrd *clk_wzrd = to_clk_wzrd(nb);
if (clk_wzrd->suspended)
return NOTIFY_OK;
if (ndata->clk == clk_wzrd->clk_in1)
max = clk_wzrd_max_freq[clk_wzrd->speed_grade - 1];
else if (ndata->clk == clk_wzrd->axi_clk)
max = WZRD_ACLK_MAX_FREQ;
else
return NOTIFY_DONE; /* should never happen */
switch (event) {
case PRE_RATE_CHANGE:
if (ndata->new_rate > max)
return NOTIFY_BAD;
return NOTIFY_OK;
case POST_RATE_CHANGE:
case ABORT_RATE_CHANGE:
default:
return NOTIFY_DONE;
}
}
static int __maybe_unused clk_wzrd_suspend(struct device *dev)
{
struct clk_wzrd *clk_wzrd = dev_get_drvdata(dev);
clk_disable_unprepare(clk_wzrd->axi_clk);
clk_wzrd->suspended = true;
return 0;
}
static int __maybe_unused clk_wzrd_resume(struct device *dev)
{
int ret;
struct clk_wzrd *clk_wzrd = dev_get_drvdata(dev);
ret = clk_prepare_enable(clk_wzrd->axi_clk);
if (ret) {
dev_err(dev, "unable to enable s_axi_aclk\n");
return ret;
}
clk_wzrd->suspended = false;
return 0;
}
static SIMPLE_DEV_PM_OPS(clk_wzrd_dev_pm_ops, clk_wzrd_suspend,
clk_wzrd_resume);
static int clk_wzrd_probe(struct platform_device *pdev)
{
int i, ret;
u32 reg, reg_f, mult;
unsigned long rate;
const char *clk_name;
void __iomem *ctrl_reg;
struct clk_wzrd *clk_wzrd;
struct device_node *np = pdev->dev.of_node;
int nr_outputs;
unsigned long flags = 0;
clk_wzrd = devm_kzalloc(&pdev->dev, sizeof(*clk_wzrd), GFP_KERNEL);
if (!clk_wzrd)
return -ENOMEM;
platform_set_drvdata(pdev, clk_wzrd);
clk_wzrd->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(clk_wzrd->base))
return PTR_ERR(clk_wzrd->base);
ret = of_property_read_u32(np, "xlnx,speed-grade", &clk_wzrd->speed_grade);
if (!ret) {
if (clk_wzrd->speed_grade < 1 || clk_wzrd->speed_grade > 3) {
dev_warn(&pdev->dev, "invalid speed grade '%d'\n",
clk_wzrd->speed_grade);
clk_wzrd->speed_grade = 0;
}
}
clk_wzrd->clk_in1 = devm_clk_get(&pdev->dev, "clk_in1");
if (IS_ERR(clk_wzrd->clk_in1)) {
if (clk_wzrd->clk_in1 != ERR_PTR(-EPROBE_DEFER))
dev_err(&pdev->dev, "clk_in1 not found\n");
return PTR_ERR(clk_wzrd->clk_in1);
}
clk_wzrd->axi_clk = devm_clk_get(&pdev->dev, "s_axi_aclk");
if (IS_ERR(clk_wzrd->axi_clk)) {
if (clk_wzrd->axi_clk != ERR_PTR(-EPROBE_DEFER))
dev_err(&pdev->dev, "s_axi_aclk not found\n");
return PTR_ERR(clk_wzrd->axi_clk);
}
ret = clk_prepare_enable(clk_wzrd->axi_clk);
if (ret) {
dev_err(&pdev->dev, "enabling s_axi_aclk failed\n");
return ret;
}
rate = clk_get_rate(clk_wzrd->axi_clk);
if (rate > WZRD_ACLK_MAX_FREQ) {
dev_err(&pdev->dev, "s_axi_aclk frequency (%lu) too high\n",
rate);
ret = -EINVAL;
goto err_disable_clk;
}
reg = readl(clk_wzrd->base + WZRD_CLK_CFG_REG(0));
reg_f = reg & WZRD_CLKFBOUT_FRAC_MASK;
reg_f = reg_f >> WZRD_CLKFBOUT_FRAC_SHIFT;
reg = reg & WZRD_CLKFBOUT_MULT_MASK;
reg = reg >> WZRD_CLKFBOUT_MULT_SHIFT;
mult = (reg * 1000) + reg_f;
clk_name = kasprintf(GFP_KERNEL, "%s_mul", dev_name(&pdev->dev));
if (!clk_name) {
ret = -ENOMEM;
goto err_disable_clk;
}
ret = of_property_read_u32(np, "nr-outputs", &nr_outputs);
if (ret || nr_outputs > WZRD_NUM_OUTPUTS) {
ret = -EINVAL;
goto err_disable_clk;
}
if (nr_outputs == 1)
flags = CLK_SET_RATE_PARENT;
clk_wzrd->clks_internal[wzrd_clk_mul] = clk_register_fixed_factor
(&pdev->dev, clk_name,
__clk_get_name(clk_wzrd->clk_in1),
0, mult, 1000);
if (IS_ERR(clk_wzrd->clks_internal[wzrd_clk_mul])) {
dev_err(&pdev->dev, "unable to register fixed-factor clock\n");
ret = PTR_ERR(clk_wzrd->clks_internal[wzrd_clk_mul]);
goto err_disable_clk;
}
clk_name = kasprintf(GFP_KERNEL, "%s_mul_div", dev_name(&pdev->dev));
if (!clk_name) {
ret = -ENOMEM;
goto err_rm_int_clk;
}
ctrl_reg = clk_wzrd->base + WZRD_CLK_CFG_REG(0);
/* register div */
clk_wzrd->clks_internal[wzrd_clk_mul_div] = clk_register_divider
(&pdev->dev, clk_name,
__clk_get_name(clk_wzrd->clks_internal[wzrd_clk_mul]),
flags, ctrl_reg, 0, 8, CLK_DIVIDER_ONE_BASED |
CLK_DIVIDER_ALLOW_ZERO, &clkwzrd_lock);
if (IS_ERR(clk_wzrd->clks_internal[wzrd_clk_mul_div])) {
dev_err(&pdev->dev, "unable to register divider clock\n");
ret = PTR_ERR(clk_wzrd->clks_internal[wzrd_clk_mul_div]);
goto err_rm_int_clk;
}
/* register div per output */
for (i = nr_outputs - 1; i >= 0 ; i--) {
const char *clkout_name;
clkout_name = kasprintf(GFP_KERNEL, "%s_out%d", dev_name(&pdev->dev), i);
if (!clkout_name) {
ret = -ENOMEM;
goto err_rm_int_clk;
}
if (!i)
clk_wzrd->clkout[i] = clk_wzrd_register_divf
(&pdev->dev, clkout_name,
clk_name, flags,
clk_wzrd->base, (WZRD_CLK_CFG_REG(2) + i * 12),
WZRD_CLKOUT_DIVIDE_SHIFT,
WZRD_CLKOUT_DIVIDE_WIDTH,
CLK_DIVIDER_ONE_BASED | CLK_DIVIDER_ALLOW_ZERO,
NULL, &clkwzrd_lock);
else
clk_wzrd->clkout[i] = clk_wzrd_register_divider
(&pdev->dev, clkout_name,
clk_name, 0,
clk_wzrd->base, (WZRD_CLK_CFG_REG(2) + i * 12),
WZRD_CLKOUT_DIVIDE_SHIFT,
WZRD_CLKOUT_DIVIDE_WIDTH,
CLK_DIVIDER_ONE_BASED | CLK_DIVIDER_ALLOW_ZERO,
NULL, &clkwzrd_lock);
if (IS_ERR(clk_wzrd->clkout[i])) {
int j;
for (j = i + 1; j < nr_outputs; j++)
clk_unregister(clk_wzrd->clkout[j]);
dev_err(&pdev->dev,
"unable to register divider clock\n");
ret = PTR_ERR(clk_wzrd->clkout[i]);
goto err_rm_int_clks;
}
}
kfree(clk_name);
clk_wzrd->clk_data.clks = clk_wzrd->clkout;
clk_wzrd->clk_data.clk_num = ARRAY_SIZE(clk_wzrd->clkout);
of_clk_add_provider(np, of_clk_src_onecell_get, &clk_wzrd->clk_data);
if (clk_wzrd->speed_grade) {
clk_wzrd->nb.notifier_call = clk_wzrd_clk_notifier;
ret = clk_notifier_register(clk_wzrd->clk_in1,
&clk_wzrd->nb);
if (ret)
dev_warn(&pdev->dev,
"unable to register clock notifier\n");
ret = clk_notifier_register(clk_wzrd->axi_clk, &clk_wzrd->nb);
if (ret)
dev_warn(&pdev->dev,
"unable to register clock notifier\n");
}
return 0;
err_rm_int_clks:
clk_unregister(clk_wzrd->clks_internal[1]);
err_rm_int_clk:
kfree(clk_name);
clk_unregister(clk_wzrd->clks_internal[0]);
err_disable_clk:
clk_disable_unprepare(clk_wzrd->axi_clk);
return ret;
}
static int clk_wzrd_remove(struct platform_device *pdev)
{
int i;
struct clk_wzrd *clk_wzrd = platform_get_drvdata(pdev);
of_clk_del_provider(pdev->dev.of_node);
for (i = 0; i < WZRD_NUM_OUTPUTS; i++)
clk_unregister(clk_wzrd->clkout[i]);
for (i = 0; i < wzrd_clk_int_max; i++)
clk_unregister(clk_wzrd->clks_internal[i]);
if (clk_wzrd->speed_grade) {
clk_notifier_unregister(clk_wzrd->axi_clk, &clk_wzrd->nb);
clk_notifier_unregister(clk_wzrd->clk_in1, &clk_wzrd->nb);
}
clk_disable_unprepare(clk_wzrd->axi_clk);
return 0;
}
static const struct of_device_id clk_wzrd_ids[] = {
{ .compatible = "xlnx,clocking-wizard" },
{ },
};
MODULE_DEVICE_TABLE(of, clk_wzrd_ids);
static struct platform_driver clk_wzrd_driver = {
.driver = {
.name = "clk-wizard",
.of_match_table = clk_wzrd_ids,
.pm = &clk_wzrd_dev_pm_ops,
},
.probe = clk_wzrd_probe,
.remove = clk_wzrd_remove,
};
module_platform_driver(clk_wzrd_driver);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Soeren Brinkmann <soren.brinkmann@xilinx.com");
MODULE_DESCRIPTION("Driver for the Xilinx Clocking Wizard IP core");