u-boot/drivers/clk/nuvoton/clk_npcm.c
Jim Liu c7554574ff clk: nuvoton: Add support for NPCM750
Add clock controller driver for NPCM750

Signed-off-by: Jim Liu <JJLIU0@nuvoton.com>
Signed-off-by: Stanley Chu <yschu@nuvoton.com>
Reviewed-by: Sean Anderson <seanga2@gmail.com>
2022-05-05 09:28:47 -04:00

299 lines
6.3 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (c) 2022 Nuvoton Technology Corp.
*
* Formula for calculating clock rate:
* Fout = ((Fin / PRE_DIV) / div) / POST_DIV
*/
#include <div64.h>
#include <dm.h>
#include <asm/io.h>
#include <linux/bitfield.h>
#include <linux/log2.h>
#include "clk_npcm.h"
static int clkid_to_clksel(struct npcm_clk_select *selector, int id)
{
int i;
for (i = 0; i < selector->num_parents; i++) {
if (selector->parents[i].id == id)
return selector->parents[i].clksel;
}
return -EINVAL;
}
static int clksel_to_clkid(struct npcm_clk_select *selector, int clksel)
{
int i;
for (i = 0; i < selector->num_parents; i++) {
if (selector->parents[i].clksel == clksel)
return selector->parents[i].id;
}
return -EINVAL;
}
static struct npcm_clk_pll *npcm_clk_pll_get(struct npcm_clk_data *clk_data, int id)
{
struct npcm_clk_pll *pll = clk_data->clk_plls;
int i;
for (i = 0; i < clk_data->num_plls; i++) {
if (pll->id == id)
return pll;
pll++;
}
return NULL;
}
static struct npcm_clk_select *npcm_clk_selector_get(struct npcm_clk_data *clk_data,
int id)
{
struct npcm_clk_select *selector = clk_data->clk_selectors;
int i;
for (i = 0; i < clk_data->num_selectors; i++) {
if (selector->id == id)
return selector;
selector++;
}
return NULL;
}
static struct npcm_clk_div *npcm_clk_divider_get(struct npcm_clk_data *clk_data,
int id)
{
struct npcm_clk_div *divider = clk_data->clk_dividers;
int i;
for (i = 0; i < clk_data->num_dividers; i++) {
if (divider->id == id)
return divider;
divider++;
}
return NULL;
}
static ulong npcm_clk_get_fin(struct clk *clk)
{
struct npcm_clk_priv *priv = dev_get_priv(clk->dev);
struct npcm_clk_select *selector;
struct clk parent;
ulong parent_rate;
u32 val, clksel;
int ret;
selector = npcm_clk_selector_get(priv->clk_data, clk->id);
if (!selector)
return 0;
if (selector->flags & FIXED_PARENT) {
clksel = 0;
} else {
val = readl(priv->base + selector->reg);
clksel = (val & selector->mask) >> (ffs(selector->mask) - 1);
}
parent.id = clksel_to_clkid(selector, clksel);
ret = clk_request(clk->dev, &parent);
if (ret)
return 0;
parent_rate = clk_get_rate(&parent);
debug("fin of clk%lu = %lu\n", clk->id, parent_rate);
return parent_rate;
}
static u32 npcm_clk_get_div(struct clk *clk)
{
struct npcm_clk_priv *priv = dev_get_priv(clk->dev);
struct npcm_clk_div *divider;
u32 val, div;
divider = npcm_clk_divider_get(priv->clk_data, clk->id);
if (!divider)
return 0;
val = readl(priv->base + divider->reg);
div = (val & divider->mask) >> (ffs(divider->mask) - 1);
if (divider->flags & DIV_TYPE1)
div = div + 1;
else
div = 1 << div;
if (divider->flags & PRE_DIV2)
div = div << 1;
return div;
}
static u32 npcm_clk_set_div(struct clk *clk, u32 div)
{
struct npcm_clk_priv *priv = dev_get_priv(clk->dev);
struct npcm_clk_div *divider;
u32 val, clkdiv;
divider = npcm_clk_divider_get(priv->clk_data, clk->id);
if (!divider)
return -EINVAL;
if (divider->flags & PRE_DIV2)
div = div >> 1;
if (divider->flags & DIV_TYPE1)
clkdiv = div - 1;
else
clkdiv = ilog2(div);
val = readl(priv->base + divider->reg);
val &= ~divider->mask;
val |= (clkdiv << (ffs(divider->mask) - 1)) & divider->mask;
writel(val, priv->base + divider->reg);
return 0;
}
static ulong npcm_clk_get_fout(struct clk *clk)
{
ulong parent_rate;
u32 div;
parent_rate = npcm_clk_get_fin(clk);
if (!parent_rate)
return -EINVAL;
div = npcm_clk_get_div(clk);
if (!div)
return -EINVAL;
debug("fout of clk%lu = (%lu / %u)\n", clk->id, parent_rate, div);
return (parent_rate / div);
}
static ulong npcm_clk_get_pll_fout(struct clk *clk)
{
struct npcm_clk_priv *priv = dev_get_priv(clk->dev);
struct npcm_clk_pll *pll;
struct clk parent;
ulong parent_rate;
ulong fbdv, indv, otdv1, otdv2;
u32 val;
u64 ret;
pll = npcm_clk_pll_get(priv->clk_data, clk->id);
if (!pll)
return -ENODEV;
parent.id = pll->parent_id;
ret = clk_request(clk->dev, &parent);
if (ret)
return ret;
parent_rate = clk_get_rate(&parent);
val = readl(priv->base + pll->reg);
indv = FIELD_GET(PLLCON_INDV, val);
fbdv = FIELD_GET(PLLCON_FBDV, val);
otdv1 = FIELD_GET(PLLCON_OTDV1, val);
otdv2 = FIELD_GET(PLLCON_OTDV2, val);
ret = (u64)parent_rate * fbdv;
do_div(ret, indv * otdv1 * otdv2);
if (pll->flags & POST_DIV2)
do_div(ret, 2);
debug("fout of pll(id %lu) = %llu\n", clk->id, ret);
return ret;
}
static ulong npcm_clk_get_rate(struct clk *clk)
{
struct npcm_clk_priv *priv = dev_get_priv(clk->dev);
struct npcm_clk_data *clk_data = priv->clk_data;
struct clk refclk;
int ret;
debug("%s: id %lu\n", __func__, clk->id);
if (clk->id == clk_data->refclk_id) {
ret = clk_get_by_name(clk->dev, "refclk", &refclk);
if (!ret)
return clk_get_rate(&refclk);
else
return ret;
}
if (clk->id >= clk_data->pll0_id &&
clk->id < clk_data->pll0_id + clk_data->num_plls)
return npcm_clk_get_pll_fout(clk);
else
return npcm_clk_get_fout(clk);
}
static ulong npcm_clk_set_rate(struct clk *clk, ulong rate)
{
ulong parent_rate;
u32 div;
int ret;
debug("%s: id %lu, rate %lu\n", __func__, clk->id, rate);
parent_rate = npcm_clk_get_fin(clk);
if (!parent_rate)
return -EINVAL;
div = DIV_ROUND_UP(parent_rate, rate);
ret = npcm_clk_set_div(clk, div);
if (ret)
return ret;
debug("%s: rate %lu, new rate (%lu / %u)\n", __func__, rate, parent_rate, div);
return (parent_rate / div);
}
static int npcm_clk_set_parent(struct clk *clk, struct clk *parent)
{
struct npcm_clk_priv *priv = dev_get_priv(clk->dev);
struct npcm_clk_select *selector;
int clksel;
u32 val;
debug("%s: id %lu, parent %lu\n", __func__, clk->id, parent->id);
selector = npcm_clk_selector_get(priv->clk_data, clk->id);
if (!selector)
return -EINVAL;
clksel = clkid_to_clksel(selector, parent->id);
if (clksel < 0)
return -EINVAL;
val = readl(priv->base + selector->reg);
val &= ~selector->mask;
val |= clksel << (ffs(selector->mask) - 1);
writel(val, priv->base + selector->reg);
return 0;
}
static int npcm_clk_request(struct clk *clk)
{
struct npcm_clk_priv *priv = dev_get_priv(clk->dev);
if (clk->id >= priv->num_clks)
return -EINVAL;
return 0;
}
const struct clk_ops npcm_clk_ops = {
.get_rate = npcm_clk_get_rate,
.set_rate = npcm_clk_set_rate,
.set_parent = npcm_clk_set_parent,
.request = npcm_clk_request,
};