diff options
Diffstat (limited to 'drivers/clk/at91/clk-master.c')
-rw-r--r-- | drivers/clk/at91/clk-master.c | 335 |
1 files changed, 290 insertions, 45 deletions
diff --git a/drivers/clk/at91/clk-master.c b/drivers/clk/at91/clk-master.c index aafd003b30cf..a80427980bf7 100644 --- a/drivers/clk/at91/clk-master.c +++ b/drivers/clk/at91/clk-master.c @@ -58,83 +58,309 @@ static inline bool clk_master_ready(struct clk_master *master) static int clk_master_prepare(struct clk_hw *hw) { struct clk_master *master = to_clk_master(hw); + unsigned long flags; + + spin_lock_irqsave(master->lock, flags); while (!clk_master_ready(master)) cpu_relax(); + spin_unlock_irqrestore(master->lock, flags); + return 0; } static int clk_master_is_prepared(struct clk_hw *hw) { struct clk_master *master = to_clk_master(hw); + unsigned long flags; + bool status; - return clk_master_ready(master); + spin_lock_irqsave(master->lock, flags); + status = clk_master_ready(master); + spin_unlock_irqrestore(master->lock, flags); + + return status; } -static unsigned long clk_master_recalc_rate(struct clk_hw *hw, - unsigned long parent_rate) +static unsigned long clk_master_div_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) { - u8 pres; u8 div; - unsigned long rate = parent_rate; + unsigned long flags, rate = parent_rate; struct clk_master *master = to_clk_master(hw); const struct clk_master_layout *layout = master->layout; const struct clk_master_characteristics *characteristics = master->characteristics; unsigned int mckr; + spin_lock_irqsave(master->lock, flags); regmap_read(master->regmap, master->layout->offset, &mckr); + spin_unlock_irqrestore(master->lock, flags); + mckr &= layout->mask; - pres = (mckr >> layout->pres_shift) & MASTER_PRES_MASK; div = (mckr >> MASTER_DIV_SHIFT) & MASTER_DIV_MASK; - if (characteristics->have_div3_pres && pres == MASTER_PRES_MAX) - rate /= 3; - else - rate >>= pres; - rate /= characteristics->divisors[div]; if (rate < characteristics->output.min) - pr_warn("master clk is underclocked"); + pr_warn("master clk div is underclocked"); else if (rate > characteristics->output.max) - pr_warn("master clk is overclocked"); + pr_warn("master clk div is overclocked"); return rate; } -static u8 clk_master_get_parent(struct clk_hw *hw) +static const struct clk_ops master_div_ops = { + .prepare = clk_master_prepare, + .is_prepared = clk_master_is_prepared, + .recalc_rate = clk_master_div_recalc_rate, +}; + +static int clk_master_div_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct clk_master *master = to_clk_master(hw); + const struct clk_master_characteristics *characteristics = + master->characteristics; + unsigned long flags; + int div, i; + + div = DIV_ROUND_CLOSEST(parent_rate, rate); + if (div > ARRAY_SIZE(characteristics->divisors)) + return -EINVAL; + + for (i = 0; i < ARRAY_SIZE(characteristics->divisors); i++) { + if (!characteristics->divisors[i]) + break; + + if (div == characteristics->divisors[i]) { + div = i; + break; + } + } + + if (i == ARRAY_SIZE(characteristics->divisors)) + return -EINVAL; + + spin_lock_irqsave(master->lock, flags); + regmap_update_bits(master->regmap, master->layout->offset, + (MASTER_DIV_MASK << MASTER_DIV_SHIFT), + (div << MASTER_DIV_SHIFT)); + while (!clk_master_ready(master)) + cpu_relax(); + spin_unlock_irqrestore(master->lock, flags); + + return 0; +} + +static int clk_master_div_determine_rate(struct clk_hw *hw, + struct clk_rate_request *req) +{ + struct clk_master *master = to_clk_master(hw); + const struct clk_master_characteristics *characteristics = + master->characteristics; + struct clk_hw *parent; + unsigned long parent_rate, tmp_rate, best_rate = 0; + int i, best_diff = INT_MIN, tmp_diff; + + parent = clk_hw_get_parent(hw); + if (!parent) + return -EINVAL; + + parent_rate = clk_hw_get_rate(parent); + if (!parent_rate) + return -EINVAL; + + for (i = 0; i < ARRAY_SIZE(characteristics->divisors); i++) { + if (!characteristics->divisors[i]) + break; + + tmp_rate = DIV_ROUND_CLOSEST_ULL(parent_rate, + characteristics->divisors[i]); + tmp_diff = abs(tmp_rate - req->rate); + + if (!best_rate || best_diff > tmp_diff) { + best_diff = tmp_diff; + best_rate = tmp_rate; + } + + if (!best_diff) + break; + } + + req->best_parent_rate = best_rate; + req->best_parent_hw = parent; + req->rate = best_rate; + + return 0; +} + +static const struct clk_ops master_div_ops_chg = { + .prepare = clk_master_prepare, + .is_prepared = clk_master_is_prepared, + .recalc_rate = clk_master_div_recalc_rate, + .determine_rate = clk_master_div_determine_rate, + .set_rate = clk_master_div_set_rate, +}; + +static void clk_sama7g5_master_best_diff(struct clk_rate_request *req, + struct clk_hw *parent, + unsigned long parent_rate, + long *best_rate, + long *best_diff, + u32 div) +{ + unsigned long tmp_rate, tmp_diff; + + if (div == MASTER_PRES_MAX) + tmp_rate = parent_rate / 3; + else + tmp_rate = parent_rate >> div; + + tmp_diff = abs(req->rate - tmp_rate); + + if (*best_diff < 0 || *best_diff >= tmp_diff) { + *best_rate = tmp_rate; + *best_diff = tmp_diff; + req->best_parent_rate = parent_rate; + req->best_parent_hw = parent; + } +} + +static int clk_master_pres_determine_rate(struct clk_hw *hw, + struct clk_rate_request *req) { struct clk_master *master = to_clk_master(hw); + struct clk_rate_request req_parent = *req; + const struct clk_master_characteristics *characteristics = + master->characteristics; + struct clk_hw *parent; + long best_rate = LONG_MIN, best_diff = LONG_MIN; + u32 pres; + int i; + + if (master->chg_pid < 0) + return -EOPNOTSUPP; + + parent = clk_hw_get_parent_by_index(hw, master->chg_pid); + if (!parent) + return -EOPNOTSUPP; + + for (i = 0; i <= MASTER_PRES_MAX; i++) { + if (characteristics->have_div3_pres && i == MASTER_PRES_MAX) + pres = 3; + else + pres = 1 << i; + + req_parent.rate = req->rate * pres; + if (__clk_determine_rate(parent, &req_parent)) + continue; + + clk_sama7g5_master_best_diff(req, parent, req_parent.rate, + &best_diff, &best_rate, pres); + if (!best_diff) + break; + } + + return 0; +} + +static int clk_master_pres_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct clk_master *master = to_clk_master(hw); + unsigned long flags; + unsigned int pres; + + pres = DIV_ROUND_CLOSEST(parent_rate, rate); + if (pres > MASTER_PRES_MAX) + return -EINVAL; + + else if (pres == 3) + pres = MASTER_PRES_MAX; + else + pres = ffs(pres) - 1; + + spin_lock_irqsave(master->lock, flags); + regmap_update_bits(master->regmap, master->layout->offset, + (MASTER_PRES_MASK << master->layout->pres_shift), + (pres << master->layout->pres_shift)); + + while (!clk_master_ready(master)) + cpu_relax(); + spin_unlock_irqrestore(master->lock, flags); + + return 0; +} + +static unsigned long clk_master_pres_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clk_master *master = to_clk_master(hw); + const struct clk_master_characteristics *characteristics = + master->characteristics; + unsigned long flags; + unsigned int val, pres; + + spin_lock_irqsave(master->lock, flags); + regmap_read(master->regmap, master->layout->offset, &val); + spin_unlock_irqrestore(master->lock, flags); + + pres = (val >> master->layout->pres_shift) & MASTER_PRES_MASK; + if (pres == 3 && characteristics->have_div3_pres) + pres = 3; + else + pres = (1 << pres); + + return DIV_ROUND_CLOSEST_ULL(parent_rate, pres); +} + +static u8 clk_master_pres_get_parent(struct clk_hw *hw) +{ + struct clk_master *master = to_clk_master(hw); + unsigned long flags; unsigned int mckr; + spin_lock_irqsave(master->lock, flags); regmap_read(master->regmap, master->layout->offset, &mckr); + spin_unlock_irqrestore(master->lock, flags); return mckr & AT91_PMC_CSS; } -static const struct clk_ops master_ops = { +static const struct clk_ops master_pres_ops = { .prepare = clk_master_prepare, .is_prepared = clk_master_is_prepared, - .recalc_rate = clk_master_recalc_rate, - .get_parent = clk_master_get_parent, + .recalc_rate = clk_master_pres_recalc_rate, + .get_parent = clk_master_pres_get_parent, }; -struct clk_hw * __init -at91_clk_register_master(struct regmap *regmap, +static const struct clk_ops master_pres_ops_chg = { + .prepare = clk_master_prepare, + .is_prepared = clk_master_is_prepared, + .determine_rate = clk_master_pres_determine_rate, + .recalc_rate = clk_master_pres_recalc_rate, + .get_parent = clk_master_pres_get_parent, + .set_rate = clk_master_pres_set_rate, +}; + +static struct clk_hw * __init +at91_clk_register_master_internal(struct regmap *regmap, const char *name, int num_parents, const char **parent_names, const struct clk_master_layout *layout, - const struct clk_master_characteristics *characteristics) + const struct clk_master_characteristics *characteristics, + const struct clk_ops *ops, spinlock_t *lock, u32 flags, + int chg_pid) { struct clk_master *master; struct clk_init_data init; struct clk_hw *hw; int ret; - if (!name || !num_parents || !parent_names) + if (!name || !num_parents || !parent_names || !lock) return ERR_PTR(-EINVAL); master = kzalloc(sizeof(*master), GFP_KERNEL); @@ -142,15 +368,17 @@ at91_clk_register_master(struct regmap *regmap, return ERR_PTR(-ENOMEM); init.name = name; - init.ops = &master_ops; + init.ops = ops; init.parent_names = parent_names; init.num_parents = num_parents; - init.flags = 0; + init.flags = flags; master->hw.init = &init; master->layout = layout; master->characteristics = characteristics; master->regmap = regmap; + master->chg_pid = chg_pid; + master->lock = lock; hw = &master->hw; ret = clk_hw_register(NULL, &master->hw); @@ -162,37 +390,54 @@ at91_clk_register_master(struct regmap *regmap, return hw; } -static unsigned long -clk_sama7g5_master_recalc_rate(struct clk_hw *hw, - unsigned long parent_rate) +struct clk_hw * __init +at91_clk_register_master_pres(struct regmap *regmap, + const char *name, int num_parents, + const char **parent_names, + const struct clk_master_layout *layout, + const struct clk_master_characteristics *characteristics, + spinlock_t *lock, u32 flags, int chg_pid) { - struct clk_master *master = to_clk_master(hw); + const struct clk_ops *ops; - return DIV_ROUND_CLOSEST_ULL(parent_rate, (1 << master->div)); + if (flags & CLK_SET_RATE_GATE) + ops = &master_pres_ops; + else + ops = &master_pres_ops_chg; + + return at91_clk_register_master_internal(regmap, name, num_parents, + parent_names, layout, + characteristics, ops, + lock, flags, chg_pid); } -static void clk_sama7g5_master_best_diff(struct clk_rate_request *req, - struct clk_hw *parent, - unsigned long parent_rate, - long *best_rate, - long *best_diff, - u32 div) +struct clk_hw * __init +at91_clk_register_master_div(struct regmap *regmap, + const char *name, const char *parent_name, + const struct clk_master_layout *layout, + const struct clk_master_characteristics *characteristics, + spinlock_t *lock, u32 flags) { - unsigned long tmp_rate, tmp_diff; + const struct clk_ops *ops; - if (div == MASTER_PRES_MAX) - tmp_rate = parent_rate / 3; + if (flags & CLK_SET_RATE_GATE) + ops = &master_div_ops; else - tmp_rate = parent_rate >> div; + ops = &master_div_ops_chg; - tmp_diff = abs(req->rate - tmp_rate); + return at91_clk_register_master_internal(regmap, name, 1, + &parent_name, layout, + characteristics, ops, + lock, flags, -EINVAL); +} - if (*best_diff < 0 || *best_diff >= tmp_diff) { - *best_rate = tmp_rate; - *best_diff = tmp_diff; - req->best_parent_rate = parent_rate; - req->best_parent_hw = parent; - } +static unsigned long +clk_sama7g5_master_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clk_master *master = to_clk_master(hw); + + return DIV_ROUND_CLOSEST_ULL(parent_rate, (1 << master->div)); } static int clk_sama7g5_master_determine_rate(struct clk_hw *hw, |