linux/drivers/clk/rockchip/clk.c

626 lines
16 KiB
C

/*
* Copyright (c) 2014 MundoReader S.L.
* Author: Heiko Stuebner <heiko@sntech.de>
*
* Copyright (c) 2016 Rockchip Electronics Co. Ltd.
* Author: Xing Zheng <zhengxing@rock-chips.com>
*
* based on
*
* samsung/clk.c
* Copyright (c) 2013 Samsung Electronics Co., Ltd.
* Copyright (c) 2013 Linaro Ltd.
* Author: Thomas Abraham <thomas.ab@samsung.com>
*
* 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 <linux/slab.h>
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/mfd/syscon.h>
#include <linux/regmap.h>
#include <linux/reboot.h>
#include <linux/rational.h>
#include "clk.h"
/**
* Register a clock branch.
* Most clock branches have a form like
*
* src1 --|--\
* |M |--[GATE]-[DIV]-
* src2 --|--/
*
* sometimes without one of those components.
*/
static struct clk *rockchip_clk_register_branch(const char *name,
const char *const *parent_names, u8 num_parents,
void __iomem *base,
int muxdiv_offset, u8 mux_shift, u8 mux_width, u8 mux_flags,
u8 div_shift, u8 div_width, u8 div_flags,
struct clk_div_table *div_table, int gate_offset,
u8 gate_shift, u8 gate_flags, unsigned long flags,
spinlock_t *lock)
{
struct clk *clk;
struct clk_mux *mux = NULL;
struct clk_gate *gate = NULL;
struct clk_divider *div = NULL;
const struct clk_ops *mux_ops = NULL, *div_ops = NULL,
*gate_ops = NULL;
if (num_parents > 1) {
mux = kzalloc(sizeof(*mux), GFP_KERNEL);
if (!mux)
return ERR_PTR(-ENOMEM);
mux->reg = base + muxdiv_offset;
mux->shift = mux_shift;
mux->mask = BIT(mux_width) - 1;
mux->flags = mux_flags;
mux->lock = lock;
mux_ops = (mux_flags & CLK_MUX_READ_ONLY) ? &clk_mux_ro_ops
: &clk_mux_ops;
}
if (gate_offset >= 0) {
gate = kzalloc(sizeof(*gate), GFP_KERNEL);
if (!gate)
goto err_gate;
gate->flags = gate_flags;
gate->reg = base + gate_offset;
gate->bit_idx = gate_shift;
gate->lock = lock;
gate_ops = &clk_gate_ops;
}
if (div_width > 0) {
div = kzalloc(sizeof(*div), GFP_KERNEL);
if (!div)
goto err_div;
div->flags = div_flags;
div->reg = base + muxdiv_offset;
div->shift = div_shift;
div->width = div_width;
div->lock = lock;
div->table = div_table;
div_ops = (div_flags & CLK_DIVIDER_READ_ONLY)
? &clk_divider_ro_ops
: &clk_divider_ops;
}
clk = clk_register_composite(NULL, name, parent_names, num_parents,
mux ? &mux->hw : NULL, mux_ops,
div ? &div->hw : NULL, div_ops,
gate ? &gate->hw : NULL, gate_ops,
flags);
return clk;
err_div:
kfree(gate);
err_gate:
kfree(mux);
return ERR_PTR(-ENOMEM);
}
struct rockchip_clk_frac {
struct notifier_block clk_nb;
struct clk_fractional_divider div;
struct clk_gate gate;
struct clk_mux mux;
const struct clk_ops *mux_ops;
int mux_frac_idx;
bool rate_change_remuxed;
int rate_change_idx;
};
#define to_rockchip_clk_frac_nb(nb) \
container_of(nb, struct rockchip_clk_frac, clk_nb)
static int rockchip_clk_frac_notifier_cb(struct notifier_block *nb,
unsigned long event, void *data)
{
struct clk_notifier_data *ndata = data;
struct rockchip_clk_frac *frac = to_rockchip_clk_frac_nb(nb);
struct clk_mux *frac_mux = &frac->mux;
int ret = 0;
pr_debug("%s: event %lu, old_rate %lu, new_rate: %lu\n",
__func__, event, ndata->old_rate, ndata->new_rate);
if (event == PRE_RATE_CHANGE) {
frac->rate_change_idx =
frac->mux_ops->get_parent(&frac_mux->hw);
if (frac->rate_change_idx != frac->mux_frac_idx) {
frac->mux_ops->set_parent(&frac_mux->hw,
frac->mux_frac_idx);
frac->rate_change_remuxed = 1;
}
} else if (event == POST_RATE_CHANGE) {
/*
* The POST_RATE_CHANGE notifier runs directly after the
* divider clock is set in clk_change_rate, so we'll have
* remuxed back to the original parent before clk_change_rate
* reaches the mux itself.
*/
if (frac->rate_change_remuxed) {
frac->mux_ops->set_parent(&frac_mux->hw,
frac->rate_change_idx);
frac->rate_change_remuxed = 0;
}
}
return notifier_from_errno(ret);
}
/**
* fractional divider must set that denominator is 20 times larger than
* numerator to generate precise clock frequency.
*/
static void rockchip_fractional_approximation(struct clk_hw *hw,
unsigned long rate, unsigned long *parent_rate,
unsigned long *m, unsigned long *n)
{
struct clk_fractional_divider *fd = to_clk_fd(hw);
unsigned long p_rate, p_parent_rate;
struct clk_hw *p_parent;
unsigned long scale;
p_rate = clk_hw_get_rate(clk_hw_get_parent(hw));
if ((rate * 20 > p_rate) && (p_rate % rate != 0)) {
p_parent = clk_hw_get_parent(clk_hw_get_parent(hw));
p_parent_rate = clk_hw_get_rate(p_parent);
*parent_rate = p_parent_rate;
}
/*
* Get rate closer to *parent_rate to guarantee there is no overflow
* for m and n. In the result it will be the nearest rate left shifted
* by (scale - fd->nwidth) bits.
*/
scale = fls_long(*parent_rate / rate - 1);
if (scale > fd->nwidth)
rate <<= scale - fd->nwidth;
rational_best_approximation(rate, *parent_rate,
GENMASK(fd->mwidth - 1, 0), GENMASK(fd->nwidth - 1, 0),
m, n);
}
static struct clk *rockchip_clk_register_frac_branch(
struct rockchip_clk_provider *ctx, const char *name,
const char *const *parent_names, u8 num_parents,
void __iomem *base, int muxdiv_offset, u8 div_flags,
int gate_offset, u8 gate_shift, u8 gate_flags,
unsigned long flags, struct rockchip_clk_branch *child,
spinlock_t *lock)
{
struct rockchip_clk_frac *frac;
struct clk *clk;
struct clk_gate *gate = NULL;
struct clk_fractional_divider *div = NULL;
const struct clk_ops *div_ops = NULL, *gate_ops = NULL;
if (muxdiv_offset < 0)
return ERR_PTR(-EINVAL);
if (child && child->branch_type != branch_mux) {
pr_err("%s: fractional child clock for %s can only be a mux\n",
__func__, name);
return ERR_PTR(-EINVAL);
}
frac = kzalloc(sizeof(*frac), GFP_KERNEL);
if (!frac)
return ERR_PTR(-ENOMEM);
if (gate_offset >= 0) {
gate = &frac->gate;
gate->flags = gate_flags;
gate->reg = base + gate_offset;
gate->bit_idx = gate_shift;
gate->lock = lock;
gate_ops = &clk_gate_ops;
}
div = &frac->div;
div->flags = div_flags;
div->reg = base + muxdiv_offset;
div->mshift = 16;
div->mwidth = 16;
div->mmask = GENMASK(div->mwidth - 1, 0) << div->mshift;
div->nshift = 0;
div->nwidth = 16;
div->nmask = GENMASK(div->nwidth - 1, 0) << div->nshift;
div->lock = lock;
div->approximation = rockchip_fractional_approximation;
div_ops = &clk_fractional_divider_ops;
clk = clk_register_composite(NULL, name, parent_names, num_parents,
NULL, NULL,
&div->hw, div_ops,
gate ? &gate->hw : NULL, gate_ops,
flags | CLK_SET_RATE_UNGATE);
if (IS_ERR(clk)) {
kfree(frac);
return clk;
}
if (child) {
struct clk_mux *frac_mux = &frac->mux;
struct clk_init_data init;
struct clk *mux_clk;
int i, ret;
frac->mux_frac_idx = -1;
for (i = 0; i < child->num_parents; i++) {
if (!strcmp(name, child->parent_names[i])) {
pr_debug("%s: found fractional parent in mux at pos %d\n",
__func__, i);
frac->mux_frac_idx = i;
break;
}
}
frac->mux_ops = &clk_mux_ops;
frac->clk_nb.notifier_call = rockchip_clk_frac_notifier_cb;
frac_mux->reg = base + child->muxdiv_offset;
frac_mux->shift = child->mux_shift;
frac_mux->mask = BIT(child->mux_width) - 1;
frac_mux->flags = child->mux_flags;
frac_mux->lock = lock;
frac_mux->hw.init = &init;
init.name = child->name;
init.flags = child->flags | CLK_SET_RATE_PARENT;
init.ops = frac->mux_ops;
init.parent_names = child->parent_names;
init.num_parents = child->num_parents;
mux_clk = clk_register(NULL, &frac_mux->hw);
if (IS_ERR(mux_clk))
return clk;
rockchip_clk_add_lookup(ctx, mux_clk, child->id);
/* notifier on the fraction divider to catch rate changes */
if (frac->mux_frac_idx >= 0) {
ret = clk_notifier_register(clk, &frac->clk_nb);
if (ret)
pr_err("%s: failed to register clock notifier for %s\n",
__func__, name);
} else {
pr_warn("%s: could not find %s as parent of %s, rate changes may not work\n",
__func__, name, child->name);
}
}
return clk;
}
static struct clk *rockchip_clk_register_factor_branch(const char *name,
const char *const *parent_names, u8 num_parents,
void __iomem *base, unsigned int mult, unsigned int div,
int gate_offset, u8 gate_shift, u8 gate_flags,
unsigned long flags, spinlock_t *lock)
{
struct clk *clk;
struct clk_gate *gate = NULL;
struct clk_fixed_factor *fix = NULL;
/* without gate, register a simple factor clock */
if (gate_offset == 0) {
return clk_register_fixed_factor(NULL, name,
parent_names[0], flags, mult,
div);
}
gate = kzalloc(sizeof(*gate), GFP_KERNEL);
if (!gate)
return ERR_PTR(-ENOMEM);
gate->flags = gate_flags;
gate->reg = base + gate_offset;
gate->bit_idx = gate_shift;
gate->lock = lock;
fix = kzalloc(sizeof(*fix), GFP_KERNEL);
if (!fix) {
kfree(gate);
return ERR_PTR(-ENOMEM);
}
fix->mult = mult;
fix->div = div;
clk = clk_register_composite(NULL, name, parent_names, num_parents,
NULL, NULL,
&fix->hw, &clk_fixed_factor_ops,
&gate->hw, &clk_gate_ops, flags);
if (IS_ERR(clk)) {
kfree(fix);
kfree(gate);
}
return clk;
}
struct rockchip_clk_provider * __init rockchip_clk_init(struct device_node *np,
void __iomem *base, unsigned long nr_clks)
{
struct rockchip_clk_provider *ctx;
struct clk **clk_table;
int i;
ctx = kzalloc(sizeof(struct rockchip_clk_provider), GFP_KERNEL);
if (!ctx)
return ERR_PTR(-ENOMEM);
clk_table = kcalloc(nr_clks, sizeof(struct clk *), GFP_KERNEL);
if (!clk_table)
goto err_free;
for (i = 0; i < nr_clks; ++i)
clk_table[i] = ERR_PTR(-ENOENT);
ctx->reg_base = base;
ctx->clk_data.clks = clk_table;
ctx->clk_data.clk_num = nr_clks;
ctx->cru_node = np;
spin_lock_init(&ctx->lock);
ctx->grf = syscon_regmap_lookup_by_phandle(ctx->cru_node,
"rockchip,grf");
return ctx;
err_free:
kfree(ctx);
return ERR_PTR(-ENOMEM);
}
void __init rockchip_clk_of_add_provider(struct device_node *np,
struct rockchip_clk_provider *ctx)
{
if (of_clk_add_provider(np, of_clk_src_onecell_get,
&ctx->clk_data))
pr_err("%s: could not register clk provider\n", __func__);
}
void rockchip_clk_add_lookup(struct rockchip_clk_provider *ctx,
struct clk *clk, unsigned int id)
{
if (ctx->clk_data.clks && id)
ctx->clk_data.clks[id] = clk;
}
void __init rockchip_clk_register_plls(struct rockchip_clk_provider *ctx,
struct rockchip_pll_clock *list,
unsigned int nr_pll, int grf_lock_offset)
{
struct clk *clk;
int idx;
for (idx = 0; idx < nr_pll; idx++, list++) {
clk = rockchip_clk_register_pll(ctx, list->type, list->name,
list->parent_names, list->num_parents,
list->con_offset, grf_lock_offset,
list->lock_shift, list->mode_offset,
list->mode_shift, list->rate_table,
list->flags, list->pll_flags);
if (IS_ERR(clk)) {
pr_err("%s: failed to register clock %s\n", __func__,
list->name);
continue;
}
rockchip_clk_add_lookup(ctx, clk, list->id);
}
}
void __init rockchip_clk_register_branches(
struct rockchip_clk_provider *ctx,
struct rockchip_clk_branch *list,
unsigned int nr_clk)
{
struct clk *clk = NULL;
unsigned int idx;
unsigned long flags;
for (idx = 0; idx < nr_clk; idx++, list++) {
flags = list->flags;
/* catch simple muxes */
switch (list->branch_type) {
case branch_mux:
clk = clk_register_mux(NULL, list->name,
list->parent_names, list->num_parents,
flags, ctx->reg_base + list->muxdiv_offset,
list->mux_shift, list->mux_width,
list->mux_flags, &ctx->lock);
break;
case branch_muxgrf:
clk = rockchip_clk_register_muxgrf(list->name,
list->parent_names, list->num_parents,
flags, ctx->grf, list->muxdiv_offset,
list->mux_shift, list->mux_width,
list->mux_flags);
break;
case branch_divider:
if (list->div_table)
clk = clk_register_divider_table(NULL,
list->name, list->parent_names[0],
flags,
ctx->reg_base + list->muxdiv_offset,
list->div_shift, list->div_width,
list->div_flags, list->div_table,
&ctx->lock);
else
clk = clk_register_divider(NULL, list->name,
list->parent_names[0], flags,
ctx->reg_base + list->muxdiv_offset,
list->div_shift, list->div_width,
list->div_flags, &ctx->lock);
break;
case branch_fraction_divider:
clk = rockchip_clk_register_frac_branch(ctx, list->name,
list->parent_names, list->num_parents,
ctx->reg_base, list->muxdiv_offset,
list->div_flags,
list->gate_offset, list->gate_shift,
list->gate_flags, flags, list->child,
&ctx->lock);
break;
case branch_gate:
flags |= CLK_SET_RATE_PARENT;
clk = clk_register_gate(NULL, list->name,
list->parent_names[0], flags,
ctx->reg_base + list->gate_offset,
list->gate_shift, list->gate_flags, &ctx->lock);
break;
case branch_composite:
clk = rockchip_clk_register_branch(list->name,
list->parent_names, list->num_parents,
ctx->reg_base, list->muxdiv_offset,
list->mux_shift,
list->mux_width, list->mux_flags,
list->div_shift, list->div_width,
list->div_flags, list->div_table,
list->gate_offset, list->gate_shift,
list->gate_flags, flags, &ctx->lock);
break;
case branch_mmc:
clk = rockchip_clk_register_mmc(
list->name,
list->parent_names, list->num_parents,
ctx->reg_base + list->muxdiv_offset,
list->div_shift
);
break;
case branch_inverter:
clk = rockchip_clk_register_inverter(
list->name, list->parent_names,
list->num_parents,
ctx->reg_base + list->muxdiv_offset,
list->div_shift, list->div_flags, &ctx->lock);
break;
case branch_factor:
clk = rockchip_clk_register_factor_branch(
list->name, list->parent_names,
list->num_parents, ctx->reg_base,
list->div_shift, list->div_width,
list->gate_offset, list->gate_shift,
list->gate_flags, flags, &ctx->lock);
break;
case branch_ddrclk:
clk = rockchip_clk_register_ddrclk(
list->name, list->flags,
list->parent_names, list->num_parents,
list->muxdiv_offset, list->mux_shift,
list->mux_width, list->div_shift,
list->div_width, list->div_flags,
ctx->reg_base, &ctx->lock);
break;
}
/* none of the cases above matched */
if (!clk) {
pr_err("%s: unknown clock type %d\n",
__func__, list->branch_type);
continue;
}
if (IS_ERR(clk)) {
pr_err("%s: failed to register clock %s: %ld\n",
__func__, list->name, PTR_ERR(clk));
continue;
}
rockchip_clk_add_lookup(ctx, clk, list->id);
}
}
void __init rockchip_clk_register_armclk(struct rockchip_clk_provider *ctx,
unsigned int lookup_id,
const char *name, const char *const *parent_names,
u8 num_parents,
const struct rockchip_cpuclk_reg_data *reg_data,
const struct rockchip_cpuclk_rate_table *rates,
int nrates)
{
struct clk *clk;
clk = rockchip_clk_register_cpuclk(name, parent_names, num_parents,
reg_data, rates, nrates,
ctx->reg_base, &ctx->lock);
if (IS_ERR(clk)) {
pr_err("%s: failed to register clock %s: %ld\n",
__func__, name, PTR_ERR(clk));
return;
}
rockchip_clk_add_lookup(ctx, clk, lookup_id);
}
void __init rockchip_clk_protect_critical(const char *const clocks[],
int nclocks)
{
int i;
/* Protect the clocks that needs to stay on */
for (i = 0; i < nclocks; i++) {
struct clk *clk = __clk_lookup(clocks[i]);
if (clk)
clk_prepare_enable(clk);
}
}
static void __iomem *rst_base;
static unsigned int reg_restart;
static void (*cb_restart)(void);
static int rockchip_restart_notify(struct notifier_block *this,
unsigned long mode, void *cmd)
{
if (cb_restart)
cb_restart();
writel(0xfdb9, rst_base + reg_restart);
return NOTIFY_DONE;
}
static struct notifier_block rockchip_restart_handler = {
.notifier_call = rockchip_restart_notify,
.priority = 128,
};
void __init
rockchip_register_restart_notifier(struct rockchip_clk_provider *ctx,
unsigned int reg,
void (*cb)(void))
{
int ret;
rst_base = ctx->reg_base;
reg_restart = reg;
cb_restart = cb;
ret = register_restart_handler(&rockchip_restart_handler);
if (ret)
pr_err("%s: cannot register restart handler, %d\n",
__func__, ret);
}