OpenCloudOS-Kernel/drivers/clk/imx/clk-fracn-gppll.c

324 lines
7.7 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright 2021 NXP
*/
#include <linux/bitfield.h>
#include <linux/clk-provider.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/slab.h>
#include <asm/div64.h>
#include "clk.h"
#define PLL_CTRL 0x0
#define CLKMUX_BYPASS BIT(2)
#define CLKMUX_EN BIT(1)
#define POWERUP_MASK BIT(0)
#define PLL_ANA_PRG 0x10
#define PLL_SPREAD_SPECTRUM 0x30
#define PLL_NUMERATOR 0x40
#define PLL_MFN_MASK GENMASK(31, 2)
#define PLL_DENOMINATOR 0x50
#define PLL_MFD_MASK GENMASK(29, 0)
#define PLL_DIV 0x60
#define PLL_MFI_MASK GENMASK(24, 16)
#define PLL_RDIV_MASK GENMASK(15, 13)
#define PLL_ODIV_MASK GENMASK(7, 0)
#define PLL_DFS_CTRL(x) (0x70 + (x) * 0x10)
#define PLL_STATUS 0xF0
#define LOCK_STATUS BIT(0)
#define DFS_STATUS 0xF4
#define LOCK_TIMEOUT_US 200
#define PLL_FRACN_GP(_rate, _mfi, _mfn, _mfd, _rdiv, _odiv) \
{ \
.rate = (_rate), \
.mfi = (_mfi), \
.mfn = (_mfn), \
.mfd = (_mfd), \
.rdiv = (_rdiv), \
.odiv = (_odiv), \
}
struct clk_fracn_gppll {
struct clk_hw hw;
void __iomem *base;
const struct imx_fracn_gppll_rate_table *rate_table;
int rate_count;
};
/*
* Fvco = Fref * (MFI + MFN / MFD)
* Fout = Fvco / (rdiv * odiv)
*/
static const struct imx_fracn_gppll_rate_table fracn_tbl[] = {
PLL_FRACN_GP(650000000U, 81, 0, 0, 0, 3),
PLL_FRACN_GP(594000000U, 198, 0, 0, 0, 8),
PLL_FRACN_GP(560000000U, 70, 0, 0, 0, 3),
PLL_FRACN_GP(400000000U, 50, 0, 0, 0, 3),
PLL_FRACN_GP(393216000U, 81, 92, 100, 0, 5)
};
struct imx_fracn_gppll_clk imx_fracn_gppll = {
.rate_table = fracn_tbl,
.rate_count = ARRAY_SIZE(fracn_tbl),
};
EXPORT_SYMBOL_GPL(imx_fracn_gppll);
static inline struct clk_fracn_gppll *to_clk_fracn_gppll(struct clk_hw *hw)
{
return container_of(hw, struct clk_fracn_gppll, hw);
}
static const struct imx_fracn_gppll_rate_table *
imx_get_pll_settings(struct clk_fracn_gppll *pll, unsigned long rate)
{
const struct imx_fracn_gppll_rate_table *rate_table = pll->rate_table;
int i;
for (i = 0; i < pll->rate_count; i++)
if (rate == rate_table[i].rate)
return &rate_table[i];
return NULL;
}
static long clk_fracn_gppll_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *prate)
{
struct clk_fracn_gppll *pll = to_clk_fracn_gppll(hw);
const struct imx_fracn_gppll_rate_table *rate_table = pll->rate_table;
int i;
/* Assuming rate_table is in descending order */
for (i = 0; i < pll->rate_count; i++)
if (rate >= rate_table[i].rate)
return rate_table[i].rate;
/* return minimum supported value */
return rate_table[pll->rate_count - 1].rate;
}
static unsigned long clk_fracn_gppll_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
{
struct clk_fracn_gppll *pll = to_clk_fracn_gppll(hw);
const struct imx_fracn_gppll_rate_table *rate_table = pll->rate_table;
u32 pll_numerator, pll_denominator, pll_div;
u32 mfi, mfn, mfd, rdiv, odiv;
u64 fvco = parent_rate;
long rate = 0;
int i;
pll_numerator = readl_relaxed(pll->base + PLL_NUMERATOR);
mfn = FIELD_GET(PLL_MFN_MASK, pll_numerator);
pll_denominator = readl_relaxed(pll->base + PLL_DENOMINATOR);
mfd = FIELD_GET(PLL_MFD_MASK, pll_denominator);
pll_div = readl_relaxed(pll->base + PLL_DIV);
mfi = FIELD_GET(PLL_MFI_MASK, pll_div);
rdiv = FIELD_GET(PLL_RDIV_MASK, pll_div);
rdiv = rdiv + 1;
odiv = FIELD_GET(PLL_ODIV_MASK, pll_div);
switch (odiv) {
case 0:
odiv = 2;
break;
case 1:
odiv = 3;
break;
default:
break;
}
/*
* Sometimes, the recalculated rate has deviation due to
* the frac part. So find the accurate pll rate from the table
* first, if no match rate in the table, use the rate calculated
* from the equation below.
*/
for (i = 0; i < pll->rate_count; i++) {
if (rate_table[i].mfn == mfn && rate_table[i].mfi == mfi &&
rate_table[i].mfd == mfd && rate_table[i].rdiv == rdiv &&
rate_table[i].odiv == odiv)
rate = rate_table[i].rate;
}
if (rate)
return (unsigned long)rate;
/* Fvco = Fref * (MFI + MFN / MFD) */
fvco = fvco * mfi * mfd + fvco * mfn;
do_div(fvco, mfd * rdiv * odiv);
return (unsigned long)fvco;
}
static int clk_fracn_gppll_wait_lock(struct clk_fracn_gppll *pll)
{
u32 val;
return readl_poll_timeout(pll->base + PLL_STATUS, val,
val & LOCK_STATUS, 0, LOCK_TIMEOUT_US);
}
static int clk_fracn_gppll_set_rate(struct clk_hw *hw, unsigned long drate,
unsigned long prate)
{
struct clk_fracn_gppll *pll = to_clk_fracn_gppll(hw);
const struct imx_fracn_gppll_rate_table *rate;
u32 tmp, pll_div, ana_mfn;
int ret;
rate = imx_get_pll_settings(pll, drate);
/* Disable output */
tmp = readl_relaxed(pll->base + PLL_CTRL);
tmp &= ~CLKMUX_EN;
writel_relaxed(tmp, pll->base + PLL_CTRL);
/* Power Down */
tmp &= ~POWERUP_MASK;
writel_relaxed(tmp, pll->base + PLL_CTRL);
/* Disable BYPASS */
tmp &= ~CLKMUX_BYPASS;
writel_relaxed(tmp, pll->base + PLL_CTRL);
pll_div = FIELD_PREP(PLL_RDIV_MASK, rate->rdiv) | rate->odiv |
FIELD_PREP(PLL_MFI_MASK, rate->mfi);
writel_relaxed(pll_div, pll->base + PLL_DIV);
writel_relaxed(rate->mfd, pll->base + PLL_DENOMINATOR);
writel_relaxed(FIELD_PREP(PLL_MFN_MASK, rate->mfn), pll->base + PLL_NUMERATOR);
/* Wait for 5us according to fracn mode pll doc */
udelay(5);
/* Enable Powerup */
tmp |= POWERUP_MASK;
writel_relaxed(tmp, pll->base + PLL_CTRL);
/* Wait Lock */
ret = clk_fracn_gppll_wait_lock(pll);
if (ret)
return ret;
/* Enable output */
tmp |= CLKMUX_EN;
writel_relaxed(tmp, pll->base + PLL_CTRL);
ana_mfn = readl_relaxed(pll->base + PLL_STATUS);
ana_mfn = FIELD_GET(PLL_MFN_MASK, ana_mfn);
WARN(ana_mfn != rate->mfn, "ana_mfn != rate->mfn\n");
return 0;
}
static int clk_fracn_gppll_prepare(struct clk_hw *hw)
{
struct clk_fracn_gppll *pll = to_clk_fracn_gppll(hw);
u32 val;
int ret;
val = readl_relaxed(pll->base + PLL_CTRL);
if (val & POWERUP_MASK)
return 0;
val |= CLKMUX_BYPASS;
writel_relaxed(val, pll->base + PLL_CTRL);
val |= POWERUP_MASK;
writel_relaxed(val, pll->base + PLL_CTRL);
val |= CLKMUX_EN;
writel_relaxed(val, pll->base + PLL_CTRL);
ret = clk_fracn_gppll_wait_lock(pll);
if (ret)
return ret;
val &= ~CLKMUX_BYPASS;
writel_relaxed(val, pll->base + PLL_CTRL);
return 0;
}
static int clk_fracn_gppll_is_prepared(struct clk_hw *hw)
{
struct clk_fracn_gppll *pll = to_clk_fracn_gppll(hw);
u32 val;
val = readl_relaxed(pll->base + PLL_CTRL);
return (val & POWERUP_MASK) ? 1 : 0;
}
static void clk_fracn_gppll_unprepare(struct clk_hw *hw)
{
struct clk_fracn_gppll *pll = to_clk_fracn_gppll(hw);
u32 val;
val = readl_relaxed(pll->base + PLL_CTRL);
val &= ~POWERUP_MASK;
writel_relaxed(val, pll->base + PLL_CTRL);
}
static const struct clk_ops clk_fracn_gppll_ops = {
.prepare = clk_fracn_gppll_prepare,
.unprepare = clk_fracn_gppll_unprepare,
.is_prepared = clk_fracn_gppll_is_prepared,
.recalc_rate = clk_fracn_gppll_recalc_rate,
.round_rate = clk_fracn_gppll_round_rate,
.set_rate = clk_fracn_gppll_set_rate,
};
struct clk_hw *imx_clk_fracn_gppll(const char *name, const char *parent_name, void __iomem *base,
const struct imx_fracn_gppll_clk *pll_clk)
{
struct clk_fracn_gppll *pll;
struct clk_hw *hw;
struct clk_init_data init;
int ret;
pll = kzalloc(sizeof(*pll), GFP_KERNEL);
if (!pll)
return ERR_PTR(-ENOMEM);
init.name = name;
init.flags = pll_clk->flags;
init.parent_names = &parent_name;
init.num_parents = 1;
init.ops = &clk_fracn_gppll_ops;
pll->base = base;
pll->hw.init = &init;
pll->rate_table = pll_clk->rate_table;
pll->rate_count = pll_clk->rate_count;
hw = &pll->hw;
ret = clk_hw_register(NULL, hw);
if (ret) {
pr_err("%s: failed to register pll %s %d\n", __func__, name, ret);
kfree(pll);
return ERR_PTR(ret);
}
return hw;
}
EXPORT_SYMBOL_GPL(imx_clk_fracn_gppll);