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Merge branch 'clk-at91' into clk-next

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* clk-at91:
  clk: at91: utmi: set the mainck rate
This commit is contained in:
Stephen Boyd 2017-11-14 10:07:40 -08:00
commit 7a103f0225
2 changed files with 83 additions and 14 deletions
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95
drivers/clk/at91/clk-utmi.c
View File

@ -14,14 +14,20 @@
#include <linux/of.h>
#include <linux/mfd/syscon.h>
#include <linux/regmap.h>
#include <soc/at91/atmel-sfr.h>
#include "pmc.h"
#define UTMI_FIXED_MUL 40
/*
* 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;
struct regmap *regmap_pmc;
struct regmap *regmap_sfr;
};
#define to_clk_utmi(hw) container_of(hw, struct clk_utmi, hw)
@ -37,13 +43,54 @@ static inline bool clk_utmi_ready(struct regmap *regmap)
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;
regmap_update_bits(utmi->regmap, AT91_CKGR_UCKR, uckr, uckr);
/*
* 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);
while (!clk_utmi_ready(utmi->regmap))
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;
@ -53,21 +100,22 @@ static int clk_utmi_is_prepared(struct clk_hw *hw)
{
struct clk_utmi *utmi = to_clk_utmi(hw);
return clk_utmi_ready(utmi->regmap);
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, AT91_CKGR_UCKR, AT91_PMC_UPLLEN, 0);
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 is a fixed clk multiplier */
return parent_rate * UTMI_FIXED_MUL;
/* UTMI clk rate is fixed. */
return UTMI_RATE;
}
static const struct clk_ops utmi_ops = {
@ -78,7 +126,7 @@ static const struct clk_ops utmi_ops = {
};
static struct clk_hw * __init
at91_clk_register_utmi(struct regmap *regmap,
at91_clk_register_utmi(struct regmap *regmap_pmc, struct regmap *regmap_sfr,
const char *name, const char *parent_name)
{
struct clk_utmi *utmi;
@ -97,7 +145,8 @@ at91_clk_register_utmi(struct regmap *regmap,
init.flags = CLK_SET_RATE_GATE;
utmi->hw.init = &init;
utmi->regmap = regmap;
utmi->regmap_pmc = regmap_pmc;
utmi->regmap_sfr = regmap_sfr;
hw = &utmi->hw;
ret = clk_hw_register(NULL, &utmi->hw);
@ -114,17 +163,35 @@ static void __init of_at91sam9x5_clk_utmi_setup(struct device_node *np)
struct clk_hw *hw;
const char *parent_name;
const char *name = np->name;
struct regmap *regmap;
struct regmap *regmap_pmc, *regmap_sfr;
parent_name = of_clk_get_parent_name(np, 0);
of_property_read_string(np, "clock-output-names", &name);
regmap = syscon_node_to_regmap(of_get_parent(np));
if (IS_ERR(regmap))
regmap_pmc = syscon_node_to_regmap(of_get_parent(np));
if (IS_ERR(regmap_pmc))
return;
hw = at91_clk_register_utmi(regmap, name, parent_name);
/*
* If the device supports different mainck rates, this value has to be
* set in the UTMI Clock Trimming register.
* - 9x5: mainck supports several rates but it is indicated that a
* 12 MHz is needed in case of USB.
* - sama5d3 and sama5d2: mainck supports several rates. Configuring
* the FREQ field of the UTMI Clock Trimming register is mandatory.
* - sama5d4: mainck is at 12 MHz.
*
* We only need to retrieve sama5d3 or sama5d2 sfr regmap.
*/
regmap_sfr = syscon_regmap_lookup_by_compatible("atmel,sama5d3-sfr");
if (IS_ERR(regmap_sfr)) {
regmap_sfr = syscon_regmap_lookup_by_compatible("atmel,sama5d2-sfr");
if (IS_ERR(regmap_sfr))
regmap_sfr = NULL;
}
hw = at91_clk_register_utmi(regmap_pmc, regmap_sfr, name, parent_name);
if (IS_ERR(hw))
return;

2
include/soc/at91/atmel-sfr.h
View File

@ -17,6 +17,7 @@
/* 0x08 ~ 0x0c: Reserved */
#define AT91_SFR_OHCIICR 0x10 /* OHCI INT Configuration Register */
#define AT91_SFR_OHCIISR 0x14 /* OHCI INT Status Register */
#define AT91_SFR_UTMICKTRIM 0x30 /* UTMI Clock Trimming Register */
#define AT91_SFR_I2SCLKSEL 0x90 /* I2SC Register */
/* Field definitions */
@ -28,5 +29,6 @@
AT91_OHCIICR_SUSPEND_B | \
AT91_OHCIICR_SUSPEND_C)
#define AT91_UTMICKTRIM_FREQ GENMASK(1, 0)
#endif /* _LINUX_MFD_SYSCON_ATMEL_SFR_H */