OpenCloudOS-Kernel/drivers/clk/at91/clk-utmi.c

297 lines
6.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
*/
#include <linux/clk-provider.h>
#include <linux/clkdev.h>
#include <linux/clk/at91_pmc.h>
#include <linux/of.h>
#include <linux/mfd/syscon.h>
#include <linux/regmap.h>
#include <soc/at91/atmel-sfr.h>
#include "pmc.h"
/*
* The purpose of this clock is to generate a 480 MHz signal. A different
* rate can't be configured.
*/
#define UTMI_RATE 480000000
struct clk_utmi {
struct clk_hw hw;
struct regmap *regmap_pmc;
struct regmap *regmap_sfr;
struct at91_clk_pms pms;
};
#define to_clk_utmi(hw) container_of(hw, struct clk_utmi, hw)
static inline bool clk_utmi_ready(struct regmap *regmap)
{
unsigned int status;
regmap_read(regmap, AT91_PMC_SR, &status);
return status & AT91_PMC_LOCKU;
}
static int clk_utmi_prepare(struct clk_hw *hw)
{
struct clk_hw *hw_parent;
struct clk_utmi *utmi = to_clk_utmi(hw);
unsigned int uckr = AT91_PMC_UPLLEN | AT91_PMC_UPLLCOUNT |
AT91_PMC_BIASEN;
unsigned int utmi_ref_clk_freq;
unsigned long parent_rate;
/*
* If mainck rate is different from 12 MHz, we have to configure the
* FREQ field of the SFR_UTMICKTRIM register to generate properly
* the utmi clock.
*/
hw_parent = clk_hw_get_parent(hw);
parent_rate = clk_hw_get_rate(hw_parent);
switch (parent_rate) {
case 12000000:
utmi_ref_clk_freq = 0;
break;
case 16000000:
utmi_ref_clk_freq = 1;
break;
case 24000000:
utmi_ref_clk_freq = 2;
break;
/*
* Not supported on SAMA5D2 but it's not an issue since MAINCK
* maximum value is 24 MHz.
*/
case 48000000:
utmi_ref_clk_freq = 3;
break;
default:
pr_err("UTMICK: unsupported mainck rate\n");
return -EINVAL;
}
if (utmi->regmap_sfr) {
regmap_update_bits(utmi->regmap_sfr, AT91_SFR_UTMICKTRIM,
AT91_UTMICKTRIM_FREQ, utmi_ref_clk_freq);
} else if (utmi_ref_clk_freq) {
pr_err("UTMICK: sfr node required\n");
return -EINVAL;
}
regmap_update_bits(utmi->regmap_pmc, AT91_CKGR_UCKR, uckr, uckr);
while (!clk_utmi_ready(utmi->regmap_pmc))
cpu_relax();
return 0;
}
static int clk_utmi_is_prepared(struct clk_hw *hw)
{
struct clk_utmi *utmi = to_clk_utmi(hw);
return clk_utmi_ready(utmi->regmap_pmc);
}
static void clk_utmi_unprepare(struct clk_hw *hw)
{
struct clk_utmi *utmi = to_clk_utmi(hw);
regmap_update_bits(utmi->regmap_pmc, AT91_CKGR_UCKR,
AT91_PMC_UPLLEN, 0);
}
static unsigned long clk_utmi_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
/* UTMI clk rate is fixed. */
return UTMI_RATE;
}
static int clk_utmi_save_context(struct clk_hw *hw)
{
struct clk_utmi *utmi = to_clk_utmi(hw);
utmi->pms.status = clk_utmi_is_prepared(hw);
return 0;
}
static void clk_utmi_restore_context(struct clk_hw *hw)
{
struct clk_utmi *utmi = to_clk_utmi(hw);
if (utmi->pms.status)
clk_utmi_prepare(hw);
}
static const struct clk_ops utmi_ops = {
.prepare = clk_utmi_prepare,
.unprepare = clk_utmi_unprepare,
.is_prepared = clk_utmi_is_prepared,
.recalc_rate = clk_utmi_recalc_rate,
.save_context = clk_utmi_save_context,
.restore_context = clk_utmi_restore_context,
};
static struct clk_hw * __init
at91_clk_register_utmi_internal(struct regmap *regmap_pmc,
struct regmap *regmap_sfr,
const char *name, const char *parent_name,
struct clk_hw *parent_hw,
const struct clk_ops *ops, unsigned long flags)
{
struct clk_utmi *utmi;
struct clk_hw *hw;
struct clk_init_data init = {};
int ret;
if (!(parent_name || parent_hw))
return ERR_PTR(-EINVAL);
utmi = kzalloc(sizeof(*utmi), GFP_KERNEL);
if (!utmi)
return ERR_PTR(-ENOMEM);
init.name = name;
init.ops = ops;
if (parent_hw) {
init.parent_hws = parent_hw ? (const struct clk_hw **)&parent_hw : NULL;
init.num_parents = parent_hw ? 1 : 0;
} else {
init.parent_names = parent_name ? &parent_name : NULL;
init.num_parents = parent_name ? 1 : 0;
}
init.flags = flags;
utmi->hw.init = &init;
utmi->regmap_pmc = regmap_pmc;
utmi->regmap_sfr = regmap_sfr;
hw = &utmi->hw;
ret = clk_hw_register(NULL, &utmi->hw);
if (ret) {
kfree(utmi);
hw = ERR_PTR(ret);
}
return hw;
}
struct clk_hw * __init
at91_clk_register_utmi(struct regmap *regmap_pmc, struct regmap *regmap_sfr,
const char *name, const char *parent_name,
struct clk_hw *parent_hw)
{
return at91_clk_register_utmi_internal(regmap_pmc, regmap_sfr, name,
parent_name, parent_hw, &utmi_ops, CLK_SET_RATE_GATE);
}
static int clk_utmi_sama7g5_prepare(struct clk_hw *hw)
{
struct clk_utmi *utmi = to_clk_utmi(hw);
struct clk_hw *hw_parent;
unsigned long parent_rate;
unsigned int val;
hw_parent = clk_hw_get_parent(hw);
parent_rate = clk_hw_get_rate(hw_parent);
switch (parent_rate) {
case 16000000:
val = 0;
break;
case 20000000:
val = 2;
break;
case 24000000:
val = 3;
break;
case 32000000:
val = 5;
break;
default:
pr_err("UTMICK: unsupported main_xtal rate\n");
return -EINVAL;
}
regmap_write(utmi->regmap_pmc, AT91_PMC_XTALF, val);
return 0;
}
static int clk_utmi_sama7g5_is_prepared(struct clk_hw *hw)
{
struct clk_utmi *utmi = to_clk_utmi(hw);
struct clk_hw *hw_parent;
unsigned long parent_rate;
unsigned int val;
hw_parent = clk_hw_get_parent(hw);
parent_rate = clk_hw_get_rate(hw_parent);
regmap_read(utmi->regmap_pmc, AT91_PMC_XTALF, &val);
switch (val & 0x7) {
case 0:
if (parent_rate == 16000000)
return 1;
break;
case 2:
if (parent_rate == 20000000)
return 1;
break;
case 3:
if (parent_rate == 24000000)
return 1;
break;
case 5:
if (parent_rate == 32000000)
return 1;
break;
default:
break;
}
return 0;
}
static int clk_utmi_sama7g5_save_context(struct clk_hw *hw)
{
struct clk_utmi *utmi = to_clk_utmi(hw);
utmi->pms.status = clk_utmi_sama7g5_is_prepared(hw);
return 0;
}
static void clk_utmi_sama7g5_restore_context(struct clk_hw *hw)
{
struct clk_utmi *utmi = to_clk_utmi(hw);
if (utmi->pms.status)
clk_utmi_sama7g5_prepare(hw);
}
static const struct clk_ops sama7g5_utmi_ops = {
.prepare = clk_utmi_sama7g5_prepare,
.is_prepared = clk_utmi_sama7g5_is_prepared,
.recalc_rate = clk_utmi_recalc_rate,
.save_context = clk_utmi_sama7g5_save_context,
.restore_context = clk_utmi_sama7g5_restore_context,
};
struct clk_hw * __init
at91_clk_sama7g5_register_utmi(struct regmap *regmap_pmc, const char *name,
const char *parent_name, struct clk_hw *parent_hw)
{
return at91_clk_register_utmi_internal(regmap_pmc, NULL, name,
parent_name, parent_hw, &sama7g5_utmi_ops, 0);
}