Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 | // SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2016 Freescale Semiconductor, Inc.
* Copyright 2017~2018 NXP
*
* Author: Dong Aisheng <aisheng.dong@nxp.com>
*
*/
#include <linux/clk-provider.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/slab.h>
#include "clk.h"
/* PLL Control Status Register (xPLLCSR) */
#define PLL_CSR_OFFSET 0x0
#define PLL_VLD BIT(24)
#define PLL_EN BIT(0)
/* PLL Configuration Register (xPLLCFG) */
#define PLL_CFG_OFFSET 0x08
#define BP_PLL_MULT 16
#define BM_PLL_MULT (0x7f << 16)
/* PLL Numerator Register (xPLLNUM) */
#define PLL_NUM_OFFSET 0x10
/* PLL Denominator Register (xPLLDENOM) */
#define PLL_DENOM_OFFSET 0x14
#define MAX_MFD 0x3fffffff
#define DEFAULT_MFD 1000000
struct clk_pllv4 {
struct clk_hw hw;
void __iomem *base;
};
/* Valid PLL MULT Table */
static const int pllv4_mult_table[] = {33, 27, 22, 20, 17, 16};
#define to_clk_pllv4(__hw) container_of(__hw, struct clk_pllv4, hw)
#define LOCK_TIMEOUT_US USEC_PER_MSEC
static inline int clk_pllv4_wait_lock(struct clk_pllv4 *pll)
{
u32 csr;
return readl_poll_timeout(pll->base + PLL_CSR_OFFSET,
csr, csr & PLL_VLD, 0, LOCK_TIMEOUT_US);
}
static int clk_pllv4_is_prepared(struct clk_hw *hw)
{
struct clk_pllv4 *pll = to_clk_pllv4(hw);
if (readl_relaxed(pll->base) & PLL_EN)
return 1;
return 0;
}
static unsigned long clk_pllv4_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct clk_pllv4 *pll = to_clk_pllv4(hw);
u32 mult, mfn, mfd;
u64 temp64;
mult = readl_relaxed(pll->base + PLL_CFG_OFFSET);
mult &= BM_PLL_MULT;
mult >>= BP_PLL_MULT;
mfn = readl_relaxed(pll->base + PLL_NUM_OFFSET);
mfd = readl_relaxed(pll->base + PLL_DENOM_OFFSET);
temp64 = parent_rate;
temp64 *= mfn;
do_div(temp64, mfd);
return (parent_rate * mult) + (u32)temp64;
}
static long clk_pllv4_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *prate)
{
unsigned long parent_rate = *prate;
unsigned long round_rate, i;
u32 mfn, mfd = DEFAULT_MFD;
bool found = false;
u64 temp64;
for (i = 0; i < ARRAY_SIZE(pllv4_mult_table); i++) {
round_rate = parent_rate * pllv4_mult_table[i];
if (rate >= round_rate) {
found = true;
break;
}
}
if (!found) {
pr_warn("%s: unable to round rate %lu, parent rate %lu\n",
clk_hw_get_name(hw), rate, parent_rate);
return 0;
}
if (parent_rate <= MAX_MFD)
mfd = parent_rate;
temp64 = (u64)(rate - round_rate);
temp64 *= mfd;
do_div(temp64, parent_rate);
mfn = temp64;
/*
* NOTE: The value of numerator must always be configured to be
* less than the value of the denominator. If we can't get a proper
* pair of mfn/mfd, we simply return the round_rate without using
* the frac part.
*/
if (mfn >= mfd)
return round_rate;
temp64 = (u64)parent_rate;
temp64 *= mfn;
do_div(temp64, mfd);
return round_rate + (u32)temp64;
}
static bool clk_pllv4_is_valid_mult(unsigned int mult)
{
int i;
/* check if mult is in valid MULT table */
for (i = 0; i < ARRAY_SIZE(pllv4_mult_table); i++) {
if (pllv4_mult_table[i] == mult)
return true;
}
return false;
}
static int clk_pllv4_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct clk_pllv4 *pll = to_clk_pllv4(hw);
u32 val, mult, mfn, mfd = DEFAULT_MFD;
u64 temp64;
mult = rate / parent_rate;
if (!clk_pllv4_is_valid_mult(mult))
return -EINVAL;
if (parent_rate <= MAX_MFD)
mfd = parent_rate;
temp64 = (u64)(rate - mult * parent_rate);
temp64 *= mfd;
do_div(temp64, parent_rate);
mfn = temp64;
val = readl_relaxed(pll->base + PLL_CFG_OFFSET);
val &= ~BM_PLL_MULT;
val |= mult << BP_PLL_MULT;
writel_relaxed(val, pll->base + PLL_CFG_OFFSET);
writel_relaxed(mfn, pll->base + PLL_NUM_OFFSET);
writel_relaxed(mfd, pll->base + PLL_DENOM_OFFSET);
return 0;
}
static int clk_pllv4_prepare(struct clk_hw *hw)
{
u32 val;
struct clk_pllv4 *pll = to_clk_pllv4(hw);
val = readl_relaxed(pll->base);
val |= PLL_EN;
writel_relaxed(val, pll->base);
return clk_pllv4_wait_lock(pll);
}
static void clk_pllv4_unprepare(struct clk_hw *hw)
{
u32 val;
struct clk_pllv4 *pll = to_clk_pllv4(hw);
val = readl_relaxed(pll->base);
val &= ~PLL_EN;
writel_relaxed(val, pll->base);
}
static const struct clk_ops clk_pllv4_ops = {
.recalc_rate = clk_pllv4_recalc_rate,
.round_rate = clk_pllv4_round_rate,
.set_rate = clk_pllv4_set_rate,
.prepare = clk_pllv4_prepare,
.unprepare = clk_pllv4_unprepare,
.is_prepared = clk_pllv4_is_prepared,
};
struct clk_hw *imx_clk_hw_pllv4(const char *name, const char *parent_name,
void __iomem *base)
{
struct clk_pllv4 *pll;
struct clk_hw *hw;
struct clk_init_data init;
int ret;
pll = kzalloc(sizeof(*pll), GFP_KERNEL);
if (!pll)
return ERR_PTR(-ENOMEM);
pll->base = base;
init.name = name;
init.ops = &clk_pllv4_ops;
init.parent_names = &parent_name;
init.num_parents = 1;
init.flags = CLK_SET_RATE_GATE;
pll->hw.init = &init;
hw = &pll->hw;
ret = clk_hw_register(NULL, hw);
if (ret) {
kfree(pll);
hw = ERR_PTR(ret);
}
return hw;
}
|