diff options
Diffstat (limited to 'drivers/clk/sunxi/clk-factors.c')
| -rw-r--r-- | drivers/clk/sunxi/clk-factors.c | 270 |
1 files changed, 197 insertions, 73 deletions
diff --git a/drivers/clk/sunxi/clk-factors.c b/drivers/clk/sunxi/clk-factors.c index 88523f91d9b7..4d8f0422b876 100644 --- a/drivers/clk/sunxi/clk-factors.c +++ b/drivers/clk/sunxi/clk-factors.c @@ -1,26 +1,22 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * Copyright (C) 2013 Emilio López <emilio@elopez.com.ar> * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - * * Adjustable factor-based clock implementation */ #include <linux/clk-provider.h> -#include <linux/module.h> -#include <linux/slab.h> -#include <linux/io.h> +#include <linux/delay.h> #include <linux/err.h> +#include <linux/io.h> +#include <linux/of_address.h> +#include <linux/slab.h> #include <linux/string.h> -#include <linux/delay.h> - #include "clk-factors.h" /* - * DOC: basic adjustable factor-based clock that cannot gate + * DOC: basic adjustable factor-based clock * * Traits of this clock: * prepare - clk_prepare only ensures that parents are prepared @@ -30,17 +26,11 @@ * 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 FACTORS_MAX_PARENTS 5 + +#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)) @@ -54,7 +44,7 @@ static unsigned long clk_factors_recalc_rate(struct clk_hw *hw, u32 reg; unsigned long rate; struct clk_factors *factors = to_clk_factors(hw); - struct clk_factors_config *config = factors->config; + const struct clk_factors_config *config = factors->config; /* Fetch the register value */ reg = readl(factors->reg); @@ -69,32 +59,89 @@ static unsigned long clk_factors_recalc_rate(struct clk_hw *hw, if (config->pwidth != SUNXI_FACTORS_NOT_APPLICABLE) p = FACTOR_GET(config->pshift, config->pwidth, reg); + if (factors->recalc) { + struct factors_request factors_req = { + .parent_rate = parent_rate, + .n = n, + .k = k, + .m = m, + .p = p, + }; + + /* get mux details from mux clk structure */ + if (factors->mux) + factors_req.parent_index = + (reg >> factors->mux->shift) & + factors->mux->mask; + + factors->recalc(&factors_req); + + return factors_req.rate; + } + /* Calculate the rate */ - rate = (parent_rate * n * (k + 1) >> p) / (m + 1); + rate = (parent_rate * (n + config->n_start) * (k + 1) >> p) / (m + 1); return rate; } -static long clk_factors_round_rate(struct clk_hw *hw, unsigned long rate, - unsigned long *parent_rate) +static int clk_factors_determine_rate(struct clk_hw *hw, + struct clk_rate_request *req) { struct clk_factors *factors = to_clk_factors(hw); - factors->get_factors((u32 *)&rate, (u32)*parent_rate, - NULL, NULL, NULL, NULL); + struct clk_hw *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_hw_get_num_parents(hw); + for (i = 0; i < num_parents; i++) { + struct factors_request factors_req = { + .rate = req->rate, + .parent_index = i, + }; + parent = clk_hw_get_parent_by_index(hw, i); + if (!parent) + continue; + if (clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT) + parent_rate = clk_hw_round_rate(parent, req->rate); + else + parent_rate = clk_hw_get_rate(parent); + + factors_req.parent_rate = parent_rate; + factors->get_factors(&factors_req); + child_rate = factors_req.rate; + + if (child_rate <= req->rate && child_rate > best_child_rate) { + best_parent = parent; + best = parent_rate; + best_child_rate = child_rate; + } + } - return rate; + if (!best_parent) + return -EINVAL; + + req->best_parent_hw = best_parent; + req->best_parent_rate = best; + req->rate = best_child_rate; + + return 0; } static int clk_factors_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long parent_rate) { - u8 n, k, m, p; + struct factors_request req = { + .rate = rate, + .parent_rate = parent_rate, + }; u32 reg; struct clk_factors *factors = to_clk_factors(hw); - struct clk_factors_config *config = factors->config; + const struct clk_factors_config *config = factors->config; unsigned long flags = 0; - factors->get_factors((u32 *)&rate, (u32)parent_rate, &n, &k, &m, &p); + factors->get_factors(&req); if (factors->lock) spin_lock_irqsave(factors->lock, flags); @@ -103,10 +150,10 @@ static int clk_factors_set_rate(struct clk_hw *hw, unsigned long rate, reg = readl(factors->reg); /* Set up the new factors - macros do not do anything if width is 0 */ - reg = FACTOR_SET(config->nshift, config->nwidth, reg, n); - reg = FACTOR_SET(config->kshift, config->kwidth, reg, k); - reg = FACTOR_SET(config->mshift, config->mwidth, reg, m); - reg = FACTOR_SET(config->pshift, config->pwidth, reg, p); + reg = FACTOR_SET(config->nshift, config->nwidth, reg, req.n); + reg = FACTOR_SET(config->kshift, config->kwidth, reg, req.k); + reg = FACTOR_SET(config->mshift, config->mwidth, reg, req.m); + reg = FACTOR_SET(config->pshift, config->pwidth, reg, req.p); /* Apply them now */ writel(reg, factors->reg); @@ -121,60 +168,137 @@ static int clk_factors_set_rate(struct clk_hw *hw, unsigned long rate, } static 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) +static struct clk *__sunxi_factors_register(struct device_node *node, + const struct factors_data *data, + spinlock_t *lock, void __iomem *reg, + unsigned long flags) { - struct clk_factors *factors; struct clk *clk; - struct clk_init_data init; + struct clk_factors *factors; + struct clk_gate *gate = NULL; + struct clk_mux *mux = NULL; + struct clk_hw *gate_hw = NULL; + struct clk_hw *mux_hw = NULL; + const char *clk_name = node->name; + const char *parents[FACTORS_MAX_PARENTS]; + int ret, i = 0; + + /* if we have a mux, we will have >1 parents */ + i = of_clk_parent_fill(node, parents, FACTORS_MAX_PARENTS); + + /* + * some factor clocks, such as pll5 and pll6, may have multiple + * outputs, and have their name designated in factors_data + */ + if (data->name) + clk_name = data->name; + else + of_property_read_string(node, "clock-output-names", &clk_name); - /* 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); + if (!factors) + goto err_factors; - /* struct clk_factors assignments */ + /* set up factors properties */ factors->reg = reg; - factors->config = config; + factors->config = data->table; + factors->get_factors = data->getter; + factors->recalc = data->recalc; factors->lock = lock; - factors->hw.init = &init; - factors->get_factors = get_factors; - /* register the clock */ - clk = clk_register(dev, &factors->hw); + /* Add a gate if this factor clock can be gated */ + if (data->enable) { + gate = kzalloc(sizeof(struct clk_gate), GFP_KERNEL); + if (!gate) + goto err_gate; + + factors->gate = gate; + + /* set up gate properties */ + gate->reg = reg; + gate->bit_idx = data->enable; + gate->lock = factors->lock; + gate_hw = &gate->hw; + } + + /* Add a mux if this factor clock can be muxed */ + if (data->mux) { + mux = kzalloc(sizeof(struct clk_mux), GFP_KERNEL); + if (!mux) + goto err_mux; + factors->mux = mux; + + /* set up gate properties */ + mux->reg = reg; + mux->shift = data->mux; + mux->mask = data->muxmask; + mux->lock = factors->lock; + mux_hw = &mux->hw; + } + + clk = clk_register_composite(NULL, clk_name, + parents, i, + mux_hw, &clk_mux_ops, + &factors->hw, &clk_factors_ops, + gate_hw, &clk_gate_ops, CLK_IS_CRITICAL); if (IS_ERR(clk)) - kfree(factors); + goto err_register; + + ret = of_clk_add_provider(node, of_clk_src_simple_get, clk); + if (ret) + goto err_provider; return clk; + +err_provider: + /* TODO: The composite clock stuff will leak a bit here. */ + clk_unregister(clk); +err_register: + kfree(mux); +err_mux: + kfree(gate); +err_gate: + kfree(factors); +err_factors: + return NULL; +} + +struct clk *sunxi_factors_register(struct device_node *node, + const struct factors_data *data, + spinlock_t *lock, + void __iomem *reg) +{ + return __sunxi_factors_register(node, data, lock, reg, 0); +} + +struct clk *sunxi_factors_register_critical(struct device_node *node, + const struct factors_data *data, + spinlock_t *lock, + void __iomem *reg) +{ + return __sunxi_factors_register(node, data, lock, reg, CLK_IS_CRITICAL); +} + +void sunxi_factors_unregister(struct device_node *node, struct clk *clk) +{ + struct clk_hw *hw = __clk_get_hw(clk); + struct clk_factors *factors; + + if (!hw) + return; + + factors = to_clk_factors(hw); + + of_clk_del_provider(node); + /* TODO: The composite clock stuff will leak a bit here. */ + clk_unregister(clk); + kfree(factors->mux); + kfree(factors->gate); + kfree(factors); } |
