mirror of https://gitee.com/openkylin/linux.git
296 lines
6.4 KiB
C
296 lines
6.4 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* Microchip Sparx5 SoC Clock driver.
|
|
*
|
|
* Copyright (c) 2019 Microchip Inc.
|
|
*
|
|
* Author: Lars Povlsen <lars.povlsen@microchip.com>
|
|
*/
|
|
|
|
#include <linux/io.h>
|
|
#include <linux/module.h>
|
|
#include <linux/clk-provider.h>
|
|
#include <linux/bitfield.h>
|
|
#include <linux/of.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/platform_device.h>
|
|
#include <dt-bindings/clock/microchip,sparx5.h>
|
|
|
|
#define PLL_DIV GENMASK(7, 0)
|
|
#define PLL_PRE_DIV GENMASK(10, 8)
|
|
#define PLL_ROT_DIR BIT(11)
|
|
#define PLL_ROT_SEL GENMASK(13, 12)
|
|
#define PLL_ROT_ENA BIT(14)
|
|
#define PLL_CLK_ENA BIT(15)
|
|
|
|
#define MAX_SEL 4
|
|
#define MAX_PRE BIT(3)
|
|
|
|
static const u8 sel_rates[MAX_SEL] = { 0, 2*8, 2*4, 2*2 };
|
|
|
|
static const char *clk_names[N_CLOCKS] = {
|
|
"core", "ddr", "cpu2", "arm2",
|
|
"aux1", "aux2", "aux3", "aux4",
|
|
"synce",
|
|
};
|
|
|
|
struct s5_hw_clk {
|
|
struct clk_hw hw;
|
|
void __iomem *reg;
|
|
};
|
|
|
|
struct s5_clk_data {
|
|
void __iomem *base;
|
|
struct s5_hw_clk s5_hw[N_CLOCKS];
|
|
};
|
|
|
|
struct s5_pll_conf {
|
|
unsigned long freq;
|
|
u8 div;
|
|
bool rot_ena;
|
|
u8 rot_sel;
|
|
u8 rot_dir;
|
|
u8 pre_div;
|
|
};
|
|
|
|
#define to_s5_pll(hw) container_of(hw, struct s5_hw_clk, hw)
|
|
|
|
static unsigned long s5_calc_freq(unsigned long parent_rate,
|
|
const struct s5_pll_conf *conf)
|
|
{
|
|
unsigned long rate = parent_rate / conf->div;
|
|
|
|
if (conf->rot_ena) {
|
|
int sign = conf->rot_dir ? -1 : 1;
|
|
int divt = sel_rates[conf->rot_sel] * (1 + conf->pre_div);
|
|
int divb = divt + sign;
|
|
|
|
rate = mult_frac(rate, divt, divb);
|
|
rate = roundup(rate, 1000);
|
|
}
|
|
|
|
return rate;
|
|
}
|
|
|
|
static void s5_search_fractional(unsigned long rate,
|
|
unsigned long parent_rate,
|
|
int div,
|
|
struct s5_pll_conf *conf)
|
|
{
|
|
struct s5_pll_conf best;
|
|
ulong cur_offset, best_offset = rate;
|
|
int d, i, j;
|
|
|
|
memset(conf, 0, sizeof(*conf));
|
|
conf->div = div;
|
|
conf->rot_ena = 1; /* Fractional rate */
|
|
|
|
for (d = 0; best_offset > 0 && d <= 1 ; d++) {
|
|
conf->rot_dir = !!d;
|
|
for (i = 0; best_offset > 0 && i < MAX_PRE; i++) {
|
|
conf->pre_div = i;
|
|
for (j = 1; best_offset > 0 && j < MAX_SEL; j++) {
|
|
conf->rot_sel = j;
|
|
conf->freq = s5_calc_freq(parent_rate, conf);
|
|
cur_offset = abs(rate - conf->freq);
|
|
if (cur_offset < best_offset) {
|
|
best_offset = cur_offset;
|
|
best = *conf;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Best match */
|
|
*conf = best;
|
|
}
|
|
|
|
static unsigned long s5_calc_params(unsigned long rate,
|
|
unsigned long parent_rate,
|
|
struct s5_pll_conf *conf)
|
|
{
|
|
if (parent_rate % rate) {
|
|
struct s5_pll_conf alt1, alt2;
|
|
int div;
|
|
|
|
div = DIV_ROUND_CLOSEST_ULL(parent_rate, rate);
|
|
s5_search_fractional(rate, parent_rate, div, &alt1);
|
|
|
|
/* Straight match? */
|
|
if (alt1.freq == rate) {
|
|
*conf = alt1;
|
|
} else {
|
|
/* Try without rounding divider */
|
|
div = parent_rate / rate;
|
|
if (div != alt1.div) {
|
|
s5_search_fractional(rate, parent_rate, div,
|
|
&alt2);
|
|
/* Select the better match */
|
|
if (abs(rate - alt1.freq) <
|
|
abs(rate - alt2.freq))
|
|
*conf = alt1;
|
|
else
|
|
*conf = alt2;
|
|
}
|
|
}
|
|
} else {
|
|
/* Straight fit */
|
|
memset(conf, 0, sizeof(*conf));
|
|
conf->div = parent_rate / rate;
|
|
}
|
|
|
|
return conf->freq;
|
|
}
|
|
|
|
static int s5_pll_enable(struct clk_hw *hw)
|
|
{
|
|
struct s5_hw_clk *pll = to_s5_pll(hw);
|
|
u32 val = readl(pll->reg);
|
|
|
|
val |= PLL_CLK_ENA;
|
|
writel(val, pll->reg);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void s5_pll_disable(struct clk_hw *hw)
|
|
{
|
|
struct s5_hw_clk *pll = to_s5_pll(hw);
|
|
u32 val = readl(pll->reg);
|
|
|
|
val &= ~PLL_CLK_ENA;
|
|
writel(val, pll->reg);
|
|
}
|
|
|
|
static int s5_pll_set_rate(struct clk_hw *hw,
|
|
unsigned long rate,
|
|
unsigned long parent_rate)
|
|
{
|
|
struct s5_hw_clk *pll = to_s5_pll(hw);
|
|
struct s5_pll_conf conf;
|
|
unsigned long eff_rate;
|
|
u32 val;
|
|
|
|
eff_rate = s5_calc_params(rate, parent_rate, &conf);
|
|
if (eff_rate != rate)
|
|
return -EOPNOTSUPP;
|
|
|
|
val = readl(pll->reg) & PLL_CLK_ENA;
|
|
val |= FIELD_PREP(PLL_DIV, conf.div);
|
|
if (conf.rot_ena) {
|
|
val |= PLL_ROT_ENA;
|
|
val |= FIELD_PREP(PLL_ROT_SEL, conf.rot_sel);
|
|
val |= FIELD_PREP(PLL_PRE_DIV, conf.pre_div);
|
|
if (conf.rot_dir)
|
|
val |= PLL_ROT_DIR;
|
|
}
|
|
writel(val, pll->reg);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static unsigned long s5_pll_recalc_rate(struct clk_hw *hw,
|
|
unsigned long parent_rate)
|
|
{
|
|
struct s5_hw_clk *pll = to_s5_pll(hw);
|
|
struct s5_pll_conf conf;
|
|
u32 val;
|
|
|
|
val = readl(pll->reg);
|
|
|
|
if (val & PLL_CLK_ENA) {
|
|
conf.div = FIELD_GET(PLL_DIV, val);
|
|
conf.pre_div = FIELD_GET(PLL_PRE_DIV, val);
|
|
conf.rot_ena = FIELD_GET(PLL_ROT_ENA, val);
|
|
conf.rot_dir = FIELD_GET(PLL_ROT_DIR, val);
|
|
conf.rot_sel = FIELD_GET(PLL_ROT_SEL, val);
|
|
|
|
conf.freq = s5_calc_freq(parent_rate, &conf);
|
|
} else {
|
|
conf.freq = 0;
|
|
}
|
|
|
|
return conf.freq;
|
|
}
|
|
|
|
static long s5_pll_round_rate(struct clk_hw *hw, unsigned long rate,
|
|
unsigned long *parent_rate)
|
|
{
|
|
struct s5_pll_conf conf;
|
|
|
|
return s5_calc_params(rate, *parent_rate, &conf);
|
|
}
|
|
|
|
static const struct clk_ops s5_pll_ops = {
|
|
.enable = s5_pll_enable,
|
|
.disable = s5_pll_disable,
|
|
.set_rate = s5_pll_set_rate,
|
|
.round_rate = s5_pll_round_rate,
|
|
.recalc_rate = s5_pll_recalc_rate,
|
|
};
|
|
|
|
static struct clk_hw *s5_clk_hw_get(struct of_phandle_args *clkspec, void *data)
|
|
{
|
|
struct s5_clk_data *s5_clk = data;
|
|
unsigned int idx = clkspec->args[0];
|
|
|
|
if (idx >= N_CLOCKS) {
|
|
pr_err("%s: invalid index %u\n", __func__, idx);
|
|
return ERR_PTR(-EINVAL);
|
|
}
|
|
|
|
return &s5_clk->s5_hw[idx].hw;
|
|
}
|
|
|
|
static int s5_clk_probe(struct platform_device *pdev)
|
|
{
|
|
struct device *dev = &pdev->dev;
|
|
int i, ret;
|
|
struct s5_clk_data *s5_clk;
|
|
struct clk_parent_data pdata = { .index = 0 };
|
|
struct clk_init_data init = {
|
|
.ops = &s5_pll_ops,
|
|
.num_parents = 1,
|
|
.parent_data = &pdata,
|
|
};
|
|
|
|
s5_clk = devm_kzalloc(dev, sizeof(*s5_clk), GFP_KERNEL);
|
|
if (!s5_clk)
|
|
return -ENOMEM;
|
|
|
|
s5_clk->base = devm_platform_ioremap_resource(pdev, 0);
|
|
if (IS_ERR(s5_clk->base))
|
|
return PTR_ERR(s5_clk->base);
|
|
|
|
for (i = 0; i < N_CLOCKS; i++) {
|
|
struct s5_hw_clk *s5_hw = &s5_clk->s5_hw[i];
|
|
|
|
init.name = clk_names[i];
|
|
s5_hw->reg = s5_clk->base + (i * 4);
|
|
s5_hw->hw.init = &init;
|
|
ret = devm_clk_hw_register(dev, &s5_hw->hw);
|
|
if (ret) {
|
|
dev_err(dev, "failed to register %s clock\n",
|
|
init.name);
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
return devm_of_clk_add_hw_provider(dev, s5_clk_hw_get, s5_clk);
|
|
}
|
|
|
|
static const struct of_device_id s5_clk_dt_ids[] = {
|
|
{ .compatible = "microchip,sparx5-dpll", },
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(of, s5_clk_dt_ids);
|
|
|
|
static struct platform_driver s5_clk_driver = {
|
|
.probe = s5_clk_probe,
|
|
.driver = {
|
|
.name = "sparx5-clk",
|
|
.of_match_table = s5_clk_dt_ids,
|
|
},
|
|
};
|
|
builtin_platform_driver(s5_clk_driver);
|