linux-sg2042/drivers/clk/sprd/pll.c

267 lines
6.3 KiB
C

// 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);