blob: b8e2f611fd47b027fb0486a02306515e9ec7798a [file] [log] [blame]
/*
* Xilinx 'Clocking Wizard' driver
*
* Copyright (C) 2013 - 2014 Xilinx
*
* Sören Brinkmann <soren.brinkmann@xilinx.com>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License v2 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.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#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>
#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_DIVCLK_DIVIDE_SHIFT 0
#define WZRD_DIVCLK_DIVIDE_MASK (0xff << WZRD_DIVCLK_DIVIDE_SHIFT)
#define WZRD_CLKOUT_DIVIDE_SHIFT 0
#define WZRD_CLKOUT_DIVIDE_MASK (0xff << WZRD_DIVCLK_DIVIDE_SHIFT)
enum clk_wzrd_int_clks {
wzrd_clk_mul,
wzrd_clk_mul_div,
wzrd_clk_int_max
};
/**
* struct clk_wzrd:
* @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];
int speed_grade;
bool suspended;
};
#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
};
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;
unsigned long rate;
const char *clk_name;
struct clk_wzrd *clk_wzrd;
struct resource *mem;
struct device_node *np = pdev->dev.of_node;
clk_wzrd = devm_kzalloc(&pdev->dev, sizeof(*clk_wzrd), GFP_KERNEL);
if (!clk_wzrd)
return -ENOMEM;
platform_set_drvdata(pdev, clk_wzrd);
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
clk_wzrd->base = devm_ioremap_resource(&pdev->dev, mem);
if (IS_ERR(clk_wzrd->base))
return PTR_ERR(clk_wzrd->base);
ret = of_property_read_u32(np, "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;
}
/* we don't support fractional div/mul yet */
reg = readl(clk_wzrd->base + WZRD_CLK_CFG_REG(0)) &
WZRD_CLkFBOUT_FRAC_EN;
reg |= readl(clk_wzrd->base + WZRD_CLK_CFG_REG(2)) &
WZRD_CLkOUT0_FRAC_EN;
if (reg)
dev_warn(&pdev->dev, "fractional div/mul not supported\n");
/* register multiplier */
reg = (readl(clk_wzrd->base + WZRD_CLK_CFG_REG(0)) &
WZRD_CLKFBOUT_MULT_MASK) >> WZRD_CLKFBOUT_MULT_SHIFT;
clk_name = kasprintf(GFP_KERNEL, "%s_mul", dev_name(&pdev->dev));
if (!clk_name) {
ret = -ENOMEM;
goto err_disable_clk;
}
clk_wzrd->clks_internal[wzrd_clk_mul] = clk_register_fixed_factor(
&pdev->dev, clk_name,
__clk_get_name(clk_wzrd->clk_in1),
0, reg, 1);
kfree(clk_name);
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;
}
/* register div */
reg = (readl(clk_wzrd->base + WZRD_CLK_CFG_REG(0)) &
WZRD_DIVCLK_DIVIDE_MASK) >> WZRD_DIVCLK_DIVIDE_SHIFT;
clk_name = kasprintf(GFP_KERNEL, "%s_mul_div", dev_name(&pdev->dev));
if (!clk_name) {
ret = -ENOMEM;
goto err_rm_int_clk;
}
clk_wzrd->clks_internal[wzrd_clk_mul_div] = clk_register_fixed_factor(
&pdev->dev, clk_name,
__clk_get_name(clk_wzrd->clks_internal[wzrd_clk_mul]),
0, 1, reg);
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 = WZRD_NUM_OUTPUTS - 1; i >= 0 ; i--) {
const char *clkout_name;
if (of_property_read_string_index(np, "clock-output-names", i,
&clkout_name)) {
dev_err(&pdev->dev,
"clock output name not specified\n");
ret = -EINVAL;
goto err_rm_int_clks;
}
reg = readl(clk_wzrd->base + WZRD_CLK_CFG_REG(2) + i * 12);
reg &= WZRD_CLKOUT_DIVIDE_MASK;
reg >>= WZRD_CLKOUT_DIVIDE_SHIFT;
clk_wzrd->clkout[i] = clk_register_fixed_factor(&pdev->dev,
clkout_name, clk_name, 0, 1, reg);
if (IS_ERR(clk_wzrd->clkout[i])) {
int j;
for (j = i + 1; j < WZRD_NUM_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");