diff options
Diffstat (limited to 'drivers/clk/sunxi/clk-factors.c')
| -rw-r--r-- | drivers/clk/sunxi/clk-factors.c | 103 |
1 files changed, 39 insertions, 64 deletions
diff --git a/drivers/clk/sunxi/clk-factors.c b/drivers/clk/sunxi/clk-factors.c index 88523f91d9b..3806d97e529 100644 --- a/drivers/clk/sunxi/clk-factors.c +++ b/drivers/clk/sunxi/clk-factors.c @@ -30,17 +30,9 @@ * parent - fixed parent. No clk_set_parent support */ -struct clk_factors { - struct clk_hw hw; - void __iomem *reg; - struct clk_factors_config *config; - void (*get_factors) (u32 *rate, u32 parent, u8 *n, u8 *k, u8 *m, u8 *p); - spinlock_t *lock; -}; - #define to_clk_factors(_hw) container_of(_hw, struct clk_factors, hw) -#define SETMASK(len, pos) (((-1U) >> (31-len)) << (pos)) +#define SETMASK(len, pos) (((1U << (len)) - 1) << (pos)) #define CLRMASK(len, pos) (~(SETMASK(len, pos))) #define FACTOR_GET(bit, len, reg) (((reg) & SETMASK(len, bit)) >> (bit)) @@ -85,10 +77,45 @@ static long clk_factors_round_rate(struct clk_hw *hw, unsigned long rate, return rate; } +static long clk_factors_determine_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *best_parent_rate, + struct clk **best_parent_p) +{ + struct clk *clk = hw->clk, *parent, *best_parent = NULL; + int i, num_parents; + unsigned long parent_rate, best = 0, child_rate, best_child_rate = 0; + + /* find the parent that can help provide the fastest rate <= rate */ + num_parents = __clk_get_num_parents(clk); + for (i = 0; i < num_parents; i++) { + parent = clk_get_parent_by_index(clk, i); + if (!parent) + continue; + if (__clk_get_flags(clk) & CLK_SET_RATE_PARENT) + parent_rate = __clk_round_rate(parent, rate); + else + parent_rate = __clk_get_rate(parent); + + child_rate = clk_factors_round_rate(hw, rate, &parent_rate); + + if (child_rate <= rate && child_rate > best_child_rate) { + best_parent = parent; + best = parent_rate; + best_child_rate = child_rate; + } + } + + if (best_parent) + *best_parent_p = best_parent; + *best_parent_rate = best; + + return best_child_rate; +} + static int clk_factors_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long parent_rate) { - u8 n, k, m, p; + u8 n = 0, k = 0, m = 0, p = 0; u32 reg; struct clk_factors *factors = to_clk_factors(hw); struct clk_factors_config *config = factors->config; @@ -120,61 +147,9 @@ static int clk_factors_set_rate(struct clk_hw *hw, unsigned long rate, return 0; } -static const struct clk_ops clk_factors_ops = { +const struct clk_ops clk_factors_ops = { + .determine_rate = clk_factors_determine_rate, .recalc_rate = clk_factors_recalc_rate, .round_rate = clk_factors_round_rate, .set_rate = clk_factors_set_rate, }; - -/** - * clk_register_factors - register a factors clock with - * the clock framework - * @dev: device registering this clock - * @name: name of this clock - * @parent_name: name of clock's parent - * @flags: framework-specific flags - * @reg: register address to adjust factors - * @config: shift and width of factors n, k, m and p - * @get_factors: function to calculate the factors for a given frequency - * @lock: shared register lock for this clock - */ -struct clk *clk_register_factors(struct device *dev, const char *name, - const char *parent_name, - unsigned long flags, void __iomem *reg, - struct clk_factors_config *config, - void (*get_factors)(u32 *rate, u32 parent, - u8 *n, u8 *k, u8 *m, u8 *p), - spinlock_t *lock) -{ - struct clk_factors *factors; - struct clk *clk; - struct clk_init_data init; - - /* allocate the factors */ - factors = kzalloc(sizeof(struct clk_factors), GFP_KERNEL); - if (!factors) { - pr_err("%s: could not allocate factors clk\n", __func__); - return ERR_PTR(-ENOMEM); - } - - init.name = name; - init.ops = &clk_factors_ops; - init.flags = flags; - init.parent_names = (parent_name ? &parent_name : NULL); - init.num_parents = (parent_name ? 1 : 0); - - /* struct clk_factors assignments */ - factors->reg = reg; - factors->config = config; - factors->lock = lock; - factors->hw.init = &init; - factors->get_factors = get_factors; - - /* register the clock */ - clk = clk_register(dev, &factors->hw); - - if (IS_ERR(clk)) - kfree(factors); - - return clk; -} |
