clk: sprd: add adjustable pll support

Introduced a common adjustable pll clock driver for Spreadtrum SoCs.

Signed-off-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
This commit is contained in:
Chunyan Zhang 2017-12-07 20:57:10 +08:00 committed by Stephen Boyd
parent 4fcba55cc6
commit 3e37b00558
3 changed files with 375 additions and 0 deletions

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@ -5,3 +5,4 @@ clk-sprd-y += gate.o
clk-sprd-y += mux.o
clk-sprd-y += div.o
clk-sprd-y += composite.o
clk-sprd-y += pll.o

266
drivers/clk/sprd/pll.c Normal file
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@ -0,0 +1,266 @@
// SPDX-License-Identifier: GPL-2.0
//
// Spreadtrum pll clock driver
//
// Copyright (C) 2015~2017 Spreadtrum, Inc.
// Author: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/regmap.h>
#include <linux/slab.h>
#include "pll.h"
#define CLK_PLL_1M 1000000
#define CLK_PLL_10M (CLK_PLL_1M * 10)
#define pindex(pll, member) \
(pll->factors[member].shift / (8 * sizeof(pll->regs_num)))
#define pshift(pll, member) \
(pll->factors[member].shift % (8 * sizeof(pll->regs_num)))
#define pwidth(pll, member) \
pll->factors[member].width
#define pmask(pll, member) \
((pwidth(pll, member)) ? \
GENMASK(pwidth(pll, member) + pshift(pll, member) - 1, \
pshift(pll, member)) : 0)
#define pinternal(pll, cfg, member) \
(cfg[pindex(pll, member)] & pmask(pll, member))
#define pinternal_val(pll, cfg, member) \
(pinternal(pll, cfg, member) >> pshift(pll, member))
static inline unsigned int
sprd_pll_read(const struct sprd_pll *pll, u8 index)
{
const struct sprd_clk_common *common = &pll->common;
unsigned int val = 0;
if (WARN_ON(index >= pll->regs_num))
return 0;
regmap_read(common->regmap, common->reg + index * 4, &val);
return val;
}
static inline void
sprd_pll_write(const struct sprd_pll *pll, u8 index,
u32 msk, u32 val)
{
const struct sprd_clk_common *common = &pll->common;
unsigned int offset, reg;
int ret = 0;
if (WARN_ON(index >= pll->regs_num))
return;
offset = common->reg + index * 4;
ret = regmap_read(common->regmap, offset, &reg);
if (!ret)
regmap_write(common->regmap, offset, (reg & ~msk) | val);
}
static unsigned long pll_get_refin(const struct sprd_pll *pll)
{
u32 shift, mask, index, refin_id = 3;
const unsigned long refin[4] = { 2, 4, 13, 26 };
if (pwidth(pll, PLL_REFIN)) {
index = pindex(pll, PLL_REFIN);
shift = pshift(pll, PLL_REFIN);
mask = pmask(pll, PLL_REFIN);
refin_id = (sprd_pll_read(pll, index) & mask) >> shift;
if (refin_id > 3)
refin_id = 3;
}
return refin[refin_id];
}
static u32 pll_get_ibias(u64 rate, const u64 *table)
{
u32 i, num = table[0];
for (i = 1; i < num + 1; i++)
if (rate <= table[i])
break;
return (i == num + 1) ? num : i;
}
static unsigned long _sprd_pll_recalc_rate(const struct sprd_pll *pll,
unsigned long parent_rate)
{
u32 *cfg;
u32 i, mask, regs_num = pll->regs_num;
unsigned long rate, nint, kint = 0;
u64 refin;
u16 k1, k2;
cfg = kcalloc(regs_num, sizeof(*cfg), GFP_KERNEL);
if (!cfg)
return -ENOMEM;
for (i = 0; i < regs_num; i++)
cfg[i] = sprd_pll_read(pll, i);
refin = pll_get_refin(pll);
if (pinternal(pll, cfg, PLL_PREDIV))
refin = refin * 2;
if (pwidth(pll, PLL_POSTDIV) &&
((pll->fflag == 1 && pinternal(pll, cfg, PLL_POSTDIV)) ||
(!pll->fflag && !pinternal(pll, cfg, PLL_POSTDIV))))
refin = refin / 2;
if (!pinternal(pll, cfg, PLL_DIV_S)) {
rate = refin * pinternal_val(pll, cfg, PLL_N) * CLK_PLL_10M;
} else {
nint = pinternal_val(pll, cfg, PLL_NINT);
if (pinternal(pll, cfg, PLL_SDM_EN))
kint = pinternal_val(pll, cfg, PLL_KINT);
mask = pmask(pll, PLL_KINT);
k1 = pll->k1;
k2 = pll->k2;
rate = DIV_ROUND_CLOSEST_ULL(refin * kint * k1,
((mask >> __ffs(mask)) + 1)) *
k2 + refin * nint * CLK_PLL_1M;
}
return rate;
}
#define SPRD_PLL_WRITE_CHECK(pll, i, mask, val) \
(((sprd_pll_read(pll, i) & mask) == val) ? 0 : (-EFAULT))
static int _sprd_pll_set_rate(const struct sprd_pll *pll,
unsigned long rate,
unsigned long parent_rate)
{
struct reg_cfg *cfg;
int ret = 0;
u32 mask, shift, width, ibias_val, index;
u32 regs_num = pll->regs_num, i = 0;
unsigned long kint, nint;
u64 tmp, refin, fvco = rate;
cfg = kcalloc(regs_num, sizeof(*cfg), GFP_KERNEL);
if (!cfg)
return -ENOMEM;
refin = pll_get_refin(pll);
mask = pmask(pll, PLL_PREDIV);
index = pindex(pll, PLL_PREDIV);
width = pwidth(pll, PLL_PREDIV);
if (width && (sprd_pll_read(pll, index) & mask))
refin = refin * 2;
mask = pmask(pll, PLL_POSTDIV);
index = pindex(pll, PLL_POSTDIV);
width = pwidth(pll, PLL_POSTDIV);
cfg[index].msk = mask;
if (width && ((pll->fflag == 1 && fvco <= pll->fvco) ||
(pll->fflag == 0 && fvco > pll->fvco)))
cfg[index].val |= mask;
if (width && fvco <= pll->fvco)
fvco = fvco * 2;
mask = pmask(pll, PLL_DIV_S);
index = pindex(pll, PLL_DIV_S);
cfg[index].val |= mask;
cfg[index].msk |= mask;
mask = pmask(pll, PLL_SDM_EN);
index = pindex(pll, PLL_SDM_EN);
cfg[index].val |= mask;
cfg[index].msk |= mask;
nint = do_div(fvco, refin * CLK_PLL_1M);
mask = pmask(pll, PLL_NINT);
index = pindex(pll, PLL_NINT);
shift = pshift(pll, PLL_NINT);
cfg[index].val |= (nint << shift) & mask;
cfg[index].msk |= mask;
mask = pmask(pll, PLL_KINT);
index = pindex(pll, PLL_KINT);
width = pwidth(pll, PLL_KINT);
shift = pshift(pll, PLL_KINT);
tmp = fvco - refin * nint * CLK_PLL_1M;
tmp = do_div(tmp, 10000) * ((mask >> shift) + 1);
kint = DIV_ROUND_CLOSEST_ULL(tmp, refin * 100);
cfg[index].val |= (kint << shift) & mask;
cfg[index].msk |= mask;
ibias_val = pll_get_ibias(fvco, pll->itable);
mask = pmask(pll, PLL_IBIAS);
index = pindex(pll, PLL_IBIAS);
shift = pshift(pll, PLL_IBIAS);
cfg[index].val |= ibias_val << shift & mask;
cfg[index].msk |= mask;
for (i = 0; i < regs_num; i++) {
if (cfg[i].msk) {
sprd_pll_write(pll, i, cfg[i].msk, cfg[i].val);
ret |= SPRD_PLL_WRITE_CHECK(pll, i, cfg[i].msk,
cfg[i].val);
}
}
if (!ret)
udelay(pll->udelay);
return ret;
}
static unsigned long sprd_pll_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct sprd_pll *pll = hw_to_sprd_pll(hw);
return _sprd_pll_recalc_rate(pll, parent_rate);
}
static int sprd_pll_set_rate(struct clk_hw *hw,
unsigned long rate,
unsigned long parent_rate)
{
struct sprd_pll *pll = hw_to_sprd_pll(hw);
return _sprd_pll_set_rate(pll, rate, parent_rate);
}
static int sprd_pll_clk_prepare(struct clk_hw *hw)
{
struct sprd_pll *pll = hw_to_sprd_pll(hw);
udelay(pll->udelay);
return 0;
}
static long sprd_pll_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *prate)
{
return rate;
}
const struct clk_ops sprd_pll_ops = {
.prepare = sprd_pll_clk_prepare,
.recalc_rate = sprd_pll_recalc_rate,
.round_rate = sprd_pll_round_rate,
.set_rate = sprd_pll_set_rate,
};
EXPORT_SYMBOL_GPL(sprd_pll_ops);

108
drivers/clk/sprd/pll.h Normal file
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@ -0,0 +1,108 @@
// SPDX-License-Identifier: GPL-2.0
//
// Spreadtrum pll clock driver
//
// Copyright (C) 2015~2017 Spreadtrum, Inc.
// Author: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
#ifndef _SPRD_PLL_H_
#define _SPRD_PLL_H_
#include "common.h"
struct reg_cfg {
u32 val;
u32 msk;
};
struct clk_bit_field {
u8 shift;
u8 width;
};
enum {
PLL_LOCK_DONE,
PLL_DIV_S,
PLL_MOD_EN,
PLL_SDM_EN,
PLL_REFIN,
PLL_IBIAS,
PLL_N,
PLL_NINT,
PLL_KINT,
PLL_PREDIV,
PLL_POSTDIV,
PLL_FACT_MAX
};
/*
* struct sprd_pll - definition of adjustable pll clock
*
* @reg: registers used to set the configuration of pll clock,
* reg[0] shows how many registers this pll clock uses.
* @itable: pll ibias table, itable[0] means how many items this
* table includes
* @udelay delay time after setting rate
* @factors used to calculate the pll clock rate
* @fvco: fvco threshold rate
* @fflag: fvco flag
*/
struct sprd_pll {
u32 regs_num;
const u64 *itable;
const struct clk_bit_field *factors;
u16 udelay;
u16 k1;
u16 k2;
u16 fflag;
u64 fvco;
struct sprd_clk_common common;
};
#define SPRD_PLL_WITH_ITABLE_K_FVCO(_struct, _name, _parent, _reg, \
_regs_num, _itable, _factors, \
_udelay, _k1, _k2, _fflag, _fvco) \
struct sprd_pll _struct = { \
.regs_num = _regs_num, \
.itable = _itable, \
.factors = _factors, \
.udelay = _udelay, \
.k1 = _k1, \
.k2 = _k2, \
.fflag = _fflag, \
.fvco = _fvco, \
.common = { \
.regmap = NULL, \
.reg = _reg, \
.hw.init = CLK_HW_INIT(_name, \
_parent, \
&sprd_pll_ops, \
0), \
}, \
}
#define SPRD_PLL_WITH_ITABLE_K(_struct, _name, _parent, _reg, \
_regs_num, _itable, _factors, \
_udelay, _k1, _k2) \
SPRD_PLL_WITH_ITABLE_K_FVCO(_struct, _name, _parent, _reg, \
_regs_num, _itable, _factors, \
_udelay, _k1, _k2, 0, 0)
#define SPRD_PLL_WITH_ITABLE_1K(_struct, _name, _parent, _reg, \
_regs_num, _itable, _factors, _udelay) \
SPRD_PLL_WITH_ITABLE_K_FVCO(_struct, _name, _parent, _reg, \
_regs_num, _itable, _factors, \
_udelay, 1000, 1000, 0, 0)
static inline struct sprd_pll *hw_to_sprd_pll(struct clk_hw *hw)
{
struct sprd_clk_common *common = hw_to_sprd_clk_common(hw);
return container_of(common, struct sprd_pll, common);
}
extern const struct clk_ops sprd_pll_ops;
#endif /* _SPRD_PLL_H_ */