blob: a3e886a38480a75060d310bc128944e54169c80d [file] [log] [blame]
/*
* Copyright (c) 2014 MundoReader S.L.
* Author: Heiko Stuebner <heiko@sntech.de>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <asm/div64.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/regmap.h>
#include "clk.h"
#define PLL_MODE_MASK 0x3
#define PLL_MODE_SLOW 0x0
#define PLL_MODE_NORM 0x1
#define PLL_MODE_DEEP 0x2
struct rockchip_clk_pll {
struct clk_hw hw;
struct clk_mux pll_mux;
const struct clk_ops *pll_mux_ops;
struct notifier_block clk_nb;
void __iomem *reg_base;
int lock_offset;
unsigned int lock_shift;
enum rockchip_pll_type type;
const struct rockchip_pll_rate_table *rate_table;
unsigned int rate_count;
spinlock_t *lock;
};
#define to_rockchip_clk_pll(_hw) container_of(_hw, struct rockchip_clk_pll, hw)
#define to_rockchip_clk_pll_nb(nb) \
container_of(nb, struct rockchip_clk_pll, clk_nb)
static const struct rockchip_pll_rate_table *rockchip_get_pll_settings(
struct rockchip_clk_pll *pll, unsigned long rate)
{
const struct rockchip_pll_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 rockchip_pll_round_rate(struct clk_hw *hw,
unsigned long drate, unsigned long *prate)
{
struct rockchip_clk_pll *pll = to_rockchip_clk_pll(hw);
const struct rockchip_pll_rate_table *rate_table = pll->rate_table;
int i;
/* Assumming rate_table is in descending order */
for (i = 0; i < pll->rate_count; i++) {
if (drate >= rate_table[i].rate)
return rate_table[i].rate;
}
/* return minimum supported value */
return rate_table[i - 1].rate;
}
/*
* Wait for the pll to reach the locked state.
* The calling set_rate function is responsible for making sure the
* grf regmap is available.
*/
static int rockchip_pll_wait_lock(struct rockchip_clk_pll *pll)
{
struct regmap *grf = rockchip_clk_get_grf();
unsigned int val;
int delay = 24000000, ret;
while (delay > 0) {
ret = regmap_read(grf, pll->lock_offset, &val);
if (ret) {
pr_err("%s: failed to read pll lock status: %d\n",
__func__, ret);
return ret;
}
if (val & BIT(pll->lock_shift))
return 0;
delay--;
}
pr_err("%s: timeout waiting for pll to lock\n", __func__);
return -ETIMEDOUT;
}
/**
* PLL used in RK3066, RK3188 and RK3288
*/
#define RK3066_PLL_RESET_DELAY(nr) ((nr * 500) / 24 + 1)
#define RK3066_PLLCON(i) (i * 0x4)
#define RK3066_PLLCON0_OD_MASK 0xf
#define RK3066_PLLCON0_OD_SHIFT 0
#define RK3066_PLLCON0_NR_MASK 0x3f
#define RK3066_PLLCON0_NR_SHIFT 8
#define RK3066_PLLCON1_NF_MASK 0x1fff
#define RK3066_PLLCON1_NF_SHIFT 0
#define RK3066_PLLCON2_BWADJ_MASK 0xfff
#define RK3066_PLLCON2_BWADJ_SHIFT 0
#define RK3066_PLLCON3_RESET (1 << 5)
#define RK3066_PLLCON3_PWRDOWN (1 << 1)
#define RK3066_PLLCON3_BYPASS (1 << 0)
static unsigned long rockchip_rk3066_pll_recalc_rate(struct clk_hw *hw,
unsigned long prate)
{
struct rockchip_clk_pll *pll = to_rockchip_clk_pll(hw);
u64 nf, nr, no, rate64 = prate;
u32 pllcon;
pllcon = readl_relaxed(pll->reg_base + RK3066_PLLCON(3));
if (pllcon & RK3066_PLLCON3_BYPASS) {
pr_debug("%s: pll %s is bypassed\n", __func__,
__clk_get_name(hw->clk));
return prate;
}
pllcon = readl_relaxed(pll->reg_base + RK3066_PLLCON(1));
nf = (pllcon >> RK3066_PLLCON1_NF_SHIFT) & RK3066_PLLCON1_NF_MASK;
pllcon = readl_relaxed(pll->reg_base + RK3066_PLLCON(0));
nr = (pllcon >> RK3066_PLLCON0_NR_SHIFT) & RK3066_PLLCON0_NR_MASK;
no = (pllcon >> RK3066_PLLCON0_OD_SHIFT) & RK3066_PLLCON0_OD_MASK;
rate64 *= (nf + 1);
do_div(rate64, nr + 1);
do_div(rate64, no + 1);
return (unsigned long)rate64;
}
static int rockchip_rk3066_pll_set_rate(struct clk_hw *hw, unsigned long drate,
unsigned long prate)
{
struct rockchip_clk_pll *pll = to_rockchip_clk_pll(hw);
const struct rockchip_pll_rate_table *rate;
unsigned long old_rate = rockchip_rk3066_pll_recalc_rate(hw, prate);
struct regmap *grf = rockchip_clk_get_grf();
struct clk_mux *pll_mux = &pll->pll_mux;
const struct clk_ops *pll_mux_ops = pll->pll_mux_ops;
int rate_change_remuxed = 0;
int cur_parent;
int ret;
if (IS_ERR(grf)) {
pr_debug("%s: grf regmap not available, aborting rate change\n",
__func__);
return PTR_ERR(grf);
}
pr_debug("%s: changing %s from %lu to %lu with a parent rate of %lu\n",
__func__, __clk_get_name(hw->clk), old_rate, drate, prate);
/* Get required rate settings from table */
rate = rockchip_get_pll_settings(pll, drate);
if (!rate) {
pr_err("%s: Invalid rate : %lu for pll clk %s\n", __func__,
drate, __clk_get_name(hw->clk));
return -EINVAL;
}
pr_debug("%s: rate settings for %lu (nr, no, nf): (%d, %d, %d)\n",
__func__, rate->rate, rate->nr, rate->no, rate->nf);
cur_parent = pll_mux_ops->get_parent(&pll_mux->hw);
if (cur_parent == PLL_MODE_NORM) {
pll_mux_ops->set_parent(&pll_mux->hw, PLL_MODE_SLOW);
rate_change_remuxed = 1;
}
/* enter reset mode */
writel(HIWORD_UPDATE(RK3066_PLLCON3_RESET, RK3066_PLLCON3_RESET, 0),
pll->reg_base + RK3066_PLLCON(3));
/* update pll values */
writel(HIWORD_UPDATE(rate->nr - 1, RK3066_PLLCON0_NR_MASK,
RK3066_PLLCON0_NR_SHIFT) |
HIWORD_UPDATE(rate->no - 1, RK3066_PLLCON0_OD_MASK,
RK3066_PLLCON0_OD_SHIFT),
pll->reg_base + RK3066_PLLCON(0));
writel_relaxed(HIWORD_UPDATE(rate->nf - 1, RK3066_PLLCON1_NF_MASK,
RK3066_PLLCON1_NF_SHIFT),
pll->reg_base + RK3066_PLLCON(1));
writel_relaxed(HIWORD_UPDATE(rate->bwadj, RK3066_PLLCON2_BWADJ_MASK,
RK3066_PLLCON2_BWADJ_SHIFT),
pll->reg_base + RK3066_PLLCON(2));
/* leave reset and wait the reset_delay */
writel(HIWORD_UPDATE(0, RK3066_PLLCON3_RESET, 0),
pll->reg_base + RK3066_PLLCON(3));
udelay(RK3066_PLL_RESET_DELAY(rate->nr));
/* wait for the pll to lock */
ret = rockchip_pll_wait_lock(pll);
if (ret) {
pr_warn("%s: pll did not lock, trying to restore old rate %lu\n",
__func__, old_rate);
rockchip_rk3066_pll_set_rate(hw, old_rate, prate);
}
if (rate_change_remuxed)
pll_mux_ops->set_parent(&pll_mux->hw, PLL_MODE_NORM);
return ret;
}
static int rockchip_rk3066_pll_enable(struct clk_hw *hw)
{
struct rockchip_clk_pll *pll = to_rockchip_clk_pll(hw);
writel(HIWORD_UPDATE(0, RK3066_PLLCON3_PWRDOWN, 0),
pll->reg_base + RK3066_PLLCON(3));
return 0;
}
static void rockchip_rk3066_pll_disable(struct clk_hw *hw)
{
struct rockchip_clk_pll *pll = to_rockchip_clk_pll(hw);
writel(HIWORD_UPDATE(RK3066_PLLCON3_PWRDOWN,
RK3066_PLLCON3_PWRDOWN, 0),
pll->reg_base + RK3066_PLLCON(3));
}
static int rockchip_rk3066_pll_is_enabled(struct clk_hw *hw)
{
struct rockchip_clk_pll *pll = to_rockchip_clk_pll(hw);
u32 pllcon = readl(pll->reg_base + RK3066_PLLCON(3));
return !(pllcon & RK3066_PLLCON3_PWRDOWN);
}
static const struct clk_ops rockchip_rk3066_pll_clk_norate_ops = {
.recalc_rate = rockchip_rk3066_pll_recalc_rate,
.enable = rockchip_rk3066_pll_enable,
.disable = rockchip_rk3066_pll_disable,
.is_enabled = rockchip_rk3066_pll_is_enabled,
};
static const struct clk_ops rockchip_rk3066_pll_clk_ops = {
.recalc_rate = rockchip_rk3066_pll_recalc_rate,
.round_rate = rockchip_pll_round_rate,
.set_rate = rockchip_rk3066_pll_set_rate,
.enable = rockchip_rk3066_pll_enable,
.disable = rockchip_rk3066_pll_disable,
.is_enabled = rockchip_rk3066_pll_is_enabled,
};
/*
* Common registering of pll clocks
*/
struct clk *rockchip_clk_register_pll(enum rockchip_pll_type pll_type,
const char *name, const char **parent_names, u8 num_parents,
void __iomem *base, int con_offset, int grf_lock_offset,
int lock_shift, int mode_offset, int mode_shift,
struct rockchip_pll_rate_table *rate_table,
spinlock_t *lock)
{
const char *pll_parents[3];
struct clk_init_data init;
struct rockchip_clk_pll *pll;
struct clk_mux *pll_mux;
struct clk *pll_clk, *mux_clk;
char pll_name[20];
if (num_parents != 2) {
pr_err("%s: needs two parent clocks\n", __func__);
return ERR_PTR(-EINVAL);
}
/* name the actual pll */
snprintf(pll_name, sizeof(pll_name), "pll_%s", name);
pll = kzalloc(sizeof(*pll), GFP_KERNEL);
if (!pll)
return ERR_PTR(-ENOMEM);
init.name = pll_name;
/* keep all plls untouched for now */
init.flags = CLK_IGNORE_UNUSED;
init.parent_names = &parent_names[0];
init.num_parents = 1;
if (rate_table) {
int len;
/* find count of rates in rate_table */
for (len = 0; rate_table[len].rate != 0; )
len++;
pll->rate_count = len;
pll->rate_table = kmemdup(rate_table,
pll->rate_count *
sizeof(struct rockchip_pll_rate_table),
GFP_KERNEL);
WARN(!pll->rate_table,
"%s: could not allocate rate table for %s\n",
__func__, name);
}
switch (pll_type) {
case pll_rk3066:
if (!pll->rate_table)
init.ops = &rockchip_rk3066_pll_clk_norate_ops;
else
init.ops = &rockchip_rk3066_pll_clk_ops;
break;
default:
pr_warn("%s: Unknown pll type for pll clk %s\n",
__func__, name);
}
pll->hw.init = &init;
pll->type = pll_type;
pll->reg_base = base + con_offset;
pll->lock_offset = grf_lock_offset;
pll->lock_shift = lock_shift;
pll->lock = lock;
pll_clk = clk_register(NULL, &pll->hw);
if (IS_ERR(pll_clk)) {
pr_err("%s: failed to register pll clock %s : %ld\n",
__func__, name, PTR_ERR(pll_clk));
mux_clk = pll_clk;
goto err_pll;
}
/* create the mux on top of the real pll */
pll->pll_mux_ops = &clk_mux_ops;
pll_mux = &pll->pll_mux;
/* the actual muxing is xin24m, pll-output, xin32k */
pll_parents[0] = parent_names[0];
pll_parents[1] = pll_name;
pll_parents[2] = parent_names[1];
init.name = name;
init.flags = CLK_SET_RATE_PARENT;
init.ops = pll->pll_mux_ops;
init.parent_names = pll_parents;
init.num_parents = ARRAY_SIZE(pll_parents);
pll_mux->reg = base + mode_offset;
pll_mux->shift = mode_shift;
pll_mux->mask = PLL_MODE_MASK;
pll_mux->flags = 0;
pll_mux->lock = lock;
pll_mux->hw.init = &init;
if (pll_type == pll_rk3066)
pll_mux->flags |= CLK_MUX_HIWORD_MASK;
mux_clk = clk_register(NULL, &pll_mux->hw);
if (IS_ERR(mux_clk))
goto err_mux;
return mux_clk;
err_mux:
clk_unregister(pll_clk);
err_pll:
kfree(pll);
return mux_clk;
}