| Message ID | 20170710122409.3017-1-inguin@gmx.de (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Stephen Boyd |
| Headers | show |
Hi Ingo, Sorry for the delay. On Mon, 10 Jul 2017 14:24:09 +0200 Ingo van Lil <inguin@gmx.de> wrote: > The AT91 UTMI clock is a PLL generating the 480 MHz USB clock. > Originally, this PLL always had a fixed x40 multiplier, thus requiring > a 12 MHz input clock. Recent SOCs (sama5d2 and sama5d3) have a special > function register for configuring this multiplier, allowing to use > different main clock frequencies. Looks good to me, just a few nitpicks below. Once addressed you can add Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com> > > Signed-off-by: Ingo van Lil <inguin@gmx.de> > --- > drivers/clk/at91/clk-utmi.c | 105 +++++++++++++++++++++++++++++++++++++++++-- > include/soc/at91/atmel-sfr.h | 2 + > 2 files changed, 104 insertions(+), 3 deletions(-) > > diff --git a/drivers/clk/at91/clk-utmi.c b/drivers/clk/at91/clk-utmi.c > index aadabd9..d41c38b 100644 > --- a/drivers/clk/at91/clk-utmi.c > +++ b/drivers/clk/at91/clk-utmi.c > @@ -14,14 +14,29 @@ > #include <linux/of.h> > #include <linux/mfd/syscon.h> > #include <linux/regmap.h> > +#include <soc/at91/atmel-sfr.h> > > #include "pmc.h" > > +/* default multiplier for SOCs that do not allow configuration via SFR */ > #define UTMI_FIXED_MUL 40 > > +/* supported multiplier settings for SOCs that allow configuration via SFR */ > +struct utmi_multipliers { > + const char *sfr_compatible_name; const char *sfr_compat; so that you don't end with formatting issues because of the 80 chars per line rule. > + u8 multipliers[4]; > +}; > + > +static const struct utmi_multipliers utmi_multipliers[] = { > + { "atmel,sama5d2-sfr", { 40, 30, 20, 40 } }, > + { "atmel,sama5d3-sfr", { 40, 30, 20, 10 } }, > +}; > + > struct clk_utmi { > struct clk_hw hw; > struct regmap *regmap; > + struct regmap *sfr_regmap; > + const u8 *multipliers; > }; > > #define to_clk_utmi(hw) container_of(hw, struct clk_utmi, hw) > @@ -66,8 +81,67 @@ static void clk_utmi_unprepare(struct clk_hw *hw) > 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; > + struct clk_utmi *utmi = to_clk_utmi(hw); > + u8 mul = UTMI_FIXED_MUL; > + > + if (utmi->sfr_regmap && utmi->multipliers) { > + u32 regval; Add an empty line here. > + regmap_read(utmi->sfr_regmap, AT91_SFR_UTMICKTRIM, ®val); > + mul = utmi->multipliers[regval & AT91_UTMICKTRIM_FREQ_MASK]; > + } > + > + return parent_rate * mul; > +} > + > +static long clk_utmi_round_rate(struct clk_hw *hw, unsigned long rate, > + unsigned long *parent_rate) > +{ > + struct clk_utmi *utmi = to_clk_utmi(hw); > + unsigned long bestrate = 0; > + int bestdiff = -1; > + int i; > + > + if (!utmi->sfr_regmap || !utmi->multipliers) > + return *parent_rate * UTMI_FIXED_MUL; > + > + for (i = 0; i < ARRAY_SIZE(utmi_multipliers); i++) { > + unsigned long tmprate = *parent_rate * utmi->multipliers[i]; > + int tmpdiff; > + > + if (tmprate < rate) > + continue; > + > + tmpdiff = tmprate - rate; > + if (bestdiff < 0 || bestdiff > tmpdiff) { > + bestrate = tmprate; > + bestdiff = tmpdiff; > + } > + > + if (!bestdiff) > + break; > + } > + > + return bestrate; > +} > + > +static int clk_utmi_set_rate(struct clk_hw *hw, unsigned long rate, > + unsigned long parent_rate) > +{ > + struct clk_utmi *utmi = to_clk_utmi(hw); > + int i; > + > + if (!utmi->sfr_regmap || !utmi->multipliers) > + return rate == parent_rate * UTMI_FIXED_MUL ? 0 : -EINVAL; > + > + for (i = 0; i < ARRAY_SIZE(utmi_multipliers); i++) { > + if (rate == parent_rate * utmi->multipliers[i]) { > + regmap_update_bits(utmi->sfr_regmap, AT91_SFR_UTMICKTRIM, > + AT91_UTMICKTRIM_FREQ_MASK, i); > + return 0; > + } > + } > + > + return -EINVAL; > } > > static const struct clk_ops utmi_ops = { > @@ -75,10 +149,13 @@ static const struct clk_ops utmi_ops = { > .unprepare = clk_utmi_unprepare, > .is_prepared = clk_utmi_is_prepared, > .recalc_rate = clk_utmi_recalc_rate, > + .round_rate = clk_utmi_round_rate, > + .set_rate = clk_utmi_set_rate, > }; > > static struct clk_hw * __init > at91_clk_register_utmi(struct regmap *regmap, > + struct regmap *sfr_regmap, const u8 *multipliers, > const char *name, const char *parent_name) > { > struct clk_utmi *utmi; > @@ -98,6 +175,8 @@ at91_clk_register_utmi(struct regmap *regmap, > > utmi->hw.init = &init; > utmi->regmap = regmap; > + utmi->sfr_regmap = sfr_regmap; > + utmi->multipliers = multipliers; > > hw = &utmi->hw; > ret = clk_hw_register(NULL, &utmi->hw); > @@ -115,6 +194,9 @@ static void __init of_at91sam9x5_clk_utmi_setup(struct device_node *np) > const char *parent_name; > const char *name = np->name; > struct regmap *regmap; > + struct regmap *sfr_regmap; > + const u8 *multipliers = NULL; > + size_t i; > > parent_name = of_clk_get_parent_name(np, 0); > > @@ -124,7 +206,24 @@ static void __init of_at91sam9x5_clk_utmi_setup(struct device_node *np) > if (IS_ERR(regmap)) > return; > > - hw = at91_clk_register_utmi(regmap, name, parent_name); > + for (i = 0; i < ARRAY_SIZE(utmi_multipliers); i++) { > + sfr_regmap = syscon_regmap_lookup_by_compatible( > + utmi_multipliers[i].sfr_compatible_name); const char *compat = utmi_multipliers[i].sfr_compat; sfr_regmap = syscon_regmap_lookup_by_compatible(compat); This way you avoid this weird formatting. > + if (!IS_ERR(sfr_regmap)) { > + pr_debug("clk-utmi: found sfr node: %s\n", > + utmi_multipliers[i].sfr_compatible_name); > + multipliers = utmi_multipliers[i].multipliers; > + break; > + } > + } > + > + if (IS_ERR(sfr_regmap)) { > + pr_debug("clk-utmi: failed to find sfr node\n"); > + sfr_regmap = NULL; > + } > + > + hw = at91_clk_register_utmi(regmap, sfr_regmap, multipliers, > + name, parent_name); > if (IS_ERR(hw)) > return; > > diff --git a/include/soc/at91/atmel-sfr.h b/include/soc/at91/atmel-sfr.h > index 506ea8f..763948e 100644 > --- a/include/soc/at91/atmel-sfr.h > +++ b/include/soc/at91/atmel-sfr.h > @@ -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_MASK 0x03 > > #endif /* _LINUX_MFD_SYSCON_ATMEL_SFR_H */ -- To unsubscribe from this list: send the line "unsubscribe linux-clk" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/clk/at91/clk-utmi.c b/drivers/clk/at91/clk-utmi.c index aadabd9..d41c38b 100644 --- a/drivers/clk/at91/clk-utmi.c +++ b/drivers/clk/at91/clk-utmi.c @@ -14,14 +14,29 @@ #include <linux/of.h> #include <linux/mfd/syscon.h> #include <linux/regmap.h> +#include <soc/at91/atmel-sfr.h> #include "pmc.h" +/* default multiplier for SOCs that do not allow configuration via SFR */ #define UTMI_FIXED_MUL 40 +/* supported multiplier settings for SOCs that allow configuration via SFR */ +struct utmi_multipliers { + const char *sfr_compatible_name; + u8 multipliers[4]; +}; + +static const struct utmi_multipliers utmi_multipliers[] = { + { "atmel,sama5d2-sfr", { 40, 30, 20, 40 } }, + { "atmel,sama5d3-sfr", { 40, 30, 20, 10 } }, +}; + struct clk_utmi { struct clk_hw hw; struct regmap *regmap; + struct regmap *sfr_regmap; + const u8 *multipliers; }; #define to_clk_utmi(hw) container_of(hw, struct clk_utmi, hw) @@ -66,8 +81,67 @@ static void clk_utmi_unprepare(struct clk_hw *hw) 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; + struct clk_utmi *utmi = to_clk_utmi(hw); + u8 mul = UTMI_FIXED_MUL; + + if (utmi->sfr_regmap && utmi->multipliers) { + u32 regval; + regmap_read(utmi->sfr_regmap, AT91_SFR_UTMICKTRIM, ®val); + mul = utmi->multipliers[regval & AT91_UTMICKTRIM_FREQ_MASK]; + } + + return parent_rate * mul; +} + +static long clk_utmi_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent_rate) +{ + struct clk_utmi *utmi = to_clk_utmi(hw); + unsigned long bestrate = 0; + int bestdiff = -1; + int i; + + if (!utmi->sfr_regmap || !utmi->multipliers) + return *parent_rate * UTMI_FIXED_MUL; + + for (i = 0; i < ARRAY_SIZE(utmi_multipliers); i++) { + unsigned long tmprate = *parent_rate * utmi->multipliers[i]; + int tmpdiff; + + if (tmprate < rate) + continue; + + tmpdiff = tmprate - rate; + if (bestdiff < 0 || bestdiff > tmpdiff) { + bestrate = tmprate; + bestdiff = tmpdiff; + } + + if (!bestdiff) + break; + } + + return bestrate; +} + +static int clk_utmi_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct clk_utmi *utmi = to_clk_utmi(hw); + int i; + + if (!utmi->sfr_regmap || !utmi->multipliers) + return rate == parent_rate * UTMI_FIXED_MUL ? 0 : -EINVAL; + + for (i = 0; i < ARRAY_SIZE(utmi_multipliers); i++) { + if (rate == parent_rate * utmi->multipliers[i]) { + regmap_update_bits(utmi->sfr_regmap, AT91_SFR_UTMICKTRIM, + AT91_UTMICKTRIM_FREQ_MASK, i); + return 0; + } + } + + return -EINVAL; } static const struct clk_ops utmi_ops = { @@ -75,10 +149,13 @@ static const struct clk_ops utmi_ops = { .unprepare = clk_utmi_unprepare, .is_prepared = clk_utmi_is_prepared, .recalc_rate = clk_utmi_recalc_rate, + .round_rate = clk_utmi_round_rate, + .set_rate = clk_utmi_set_rate, }; static struct clk_hw * __init at91_clk_register_utmi(struct regmap *regmap, + struct regmap *sfr_regmap, const u8 *multipliers, const char *name, const char *parent_name) { struct clk_utmi *utmi; @@ -98,6 +175,8 @@ at91_clk_register_utmi(struct regmap *regmap, utmi->hw.init = &init; utmi->regmap = regmap; + utmi->sfr_regmap = sfr_regmap; + utmi->multipliers = multipliers; hw = &utmi->hw; ret = clk_hw_register(NULL, &utmi->hw); @@ -115,6 +194,9 @@ static void __init of_at91sam9x5_clk_utmi_setup(struct device_node *np) const char *parent_name; const char *name = np->name; struct regmap *regmap; + struct regmap *sfr_regmap; + const u8 *multipliers = NULL; + size_t i; parent_name = of_clk_get_parent_name(np, 0); @@ -124,7 +206,24 @@ static void __init of_at91sam9x5_clk_utmi_setup(struct device_node *np) if (IS_ERR(regmap)) return; - hw = at91_clk_register_utmi(regmap, name, parent_name); + for (i = 0; i < ARRAY_SIZE(utmi_multipliers); i++) { + sfr_regmap = syscon_regmap_lookup_by_compatible( + utmi_multipliers[i].sfr_compatible_name); + if (!IS_ERR(sfr_regmap)) { + pr_debug("clk-utmi: found sfr node: %s\n", + utmi_multipliers[i].sfr_compatible_name); + multipliers = utmi_multipliers[i].multipliers; + break; + } + } + + if (IS_ERR(sfr_regmap)) { + pr_debug("clk-utmi: failed to find sfr node\n"); + sfr_regmap = NULL; + } + + hw = at91_clk_register_utmi(regmap, sfr_regmap, multipliers, + name, parent_name); if (IS_ERR(hw)) return; diff --git a/include/soc/at91/atmel-sfr.h b/include/soc/at91/atmel-sfr.h index 506ea8f..763948e 100644 --- a/include/soc/at91/atmel-sfr.h +++ b/include/soc/at91/atmel-sfr.h @@ -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_MASK 0x03 #endif /* _LINUX_MFD_SYSCON_ATMEL_SFR_H */
The AT91 UTMI clock is a PLL generating the 480 MHz USB clock. Originally, this PLL always had a fixed x40 multiplier, thus requiring a 12 MHz input clock. Recent SOCs (sama5d2 and sama5d3) have a special function register for configuring this multiplier, allowing to use different main clock frequencies. Signed-off-by: Ingo van Lil <inguin@gmx.de> --- drivers/clk/at91/clk-utmi.c | 105 +++++++++++++++++++++++++++++++++++++++++-- include/soc/at91/atmel-sfr.h | 2 + 2 files changed, 104 insertions(+), 3 deletions(-)