diff options
Diffstat (limited to 'drivers/clk/at91/clk-utmi.c')
| -rw-r--r-- | drivers/clk/at91/clk-utmi.c | 100 |
1 files changed, 62 insertions, 38 deletions
diff --git a/drivers/clk/at91/clk-utmi.c b/drivers/clk/at91/clk-utmi.c index 6a1c5e6df3..c40af34d0d 100644 --- a/drivers/clk/at91/clk-utmi.c +++ b/drivers/clk/at91/clk-utmi.c @@ -10,21 +10,27 @@ #include <common.h> #include <clock.h> -#include <of.h> #include <linux/list.h> #include <linux/clk.h> #include <linux/clk/at91_pmc.h> #include <mfd/syscon.h> #include <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 clk; - struct regmap *regmap; const char *parent; + struct regmap *regmap_pmc; + struct regmap *regmap_sfr; }; #define to_clk_utmi(clk) container_of(clk, struct clk_utmi, clk) @@ -40,13 +46,55 @@ static inline bool clk_utmi_ready(struct regmap *regmap) static int clk_utmi_enable(struct clk *clk) { + struct clk *hw_parent; struct clk_utmi *utmi = to_clk_utmi(clk); 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_get_parent(clk); + parent_rate = clk_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_write_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_write_bits(utmi->regmap_pmc, AT91_CKGR_UCKR, uckr, uckr); - regmap_write_bits(utmi->regmap, AT91_CKGR_UCKR, uckr, uckr); - while (!clk_utmi_ready(utmi->regmap)) + while (!clk_utmi_ready(utmi->regmap_pmc)) barrier(); return 0; @@ -56,21 +104,22 @@ static int clk_utmi_is_enabled(struct clk *clk) { struct clk_utmi *utmi = to_clk_utmi(clk); - return clk_utmi_ready(utmi->regmap); + return clk_utmi_ready(utmi->regmap_pmc); } static void clk_utmi_disable(struct clk *clk) { struct clk_utmi *utmi = to_clk_utmi(clk); - regmap_write_bits(utmi->regmap, AT91_CKGR_UCKR, AT91_PMC_UPLLEN, 0); + regmap_write_bits(utmi->regmap_pmc, AT91_CKGR_UCKR, + AT91_PMC_UPLLEN, 0); } static unsigned long clk_utmi_recalc_rate(struct clk *clk, 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 = { @@ -80,8 +129,8 @@ static const struct clk_ops utmi_ops = { .recalc_rate = clk_utmi_recalc_rate, }; -static struct clk * __init -at91_clk_register_utmi(struct regmap *regmap, +struct clk * __init +at91_clk_register_utmi(struct regmap *regmap_pmc, struct regmap *regmap_sfr, const char *name, const char *parent_name) { int ret; @@ -100,7 +149,8 @@ at91_clk_register_utmi(struct regmap *regmap, /* utmi->clk.flags = CLK_SET_RATE_GATE; */ - utmi->regmap = regmap; + utmi->regmap_pmc = regmap_pmc; + utmi->regmap_sfr = regmap_sfr; ret = clk_register(&utmi->clk); if (ret) { @@ -110,29 +160,3 @@ at91_clk_register_utmi(struct regmap *regmap, return &utmi->clk; } -#if defined(CONFIG_OFTREE) && defined(CONFIG_COMMON_CLK_OF_PROVIDER) -static void __init of_at91sam9x5_clk_utmi_setup(struct device_node *np) -{ - struct clk *clk; - const char *parent_name; - const char *name = np->name; - struct regmap *regmap; - - 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)) - return; - - clk = at91_clk_register_utmi(regmap, name, parent_name); - if (IS_ERR(clk)) - return; - - of_clk_add_provider(np, of_clk_src_simple_get, clk); - return; -} -CLK_OF_DECLARE(at91sam9x5_clk_utmi, "atmel,at91sam9x5-clk-utmi", - of_at91sam9x5_clk_utmi_setup); -#endif |