| /* | 
 |  * clk-flexgen.c | 
 |  * | 
 |  * Copyright (C) ST-Microelectronics SA 2013 | 
 |  * Author:  Maxime Coquelin <maxime.coquelin@st.com> for ST-Microelectronics. | 
 |  * License terms:  GNU General Public License (GPL), version 2  */ | 
 |  | 
 | #include <linux/clk.h> | 
 | #include <linux/clk-provider.h> | 
 | #include <linux/module.h> | 
 | #include <linux/slab.h> | 
 | #include <linux/io.h> | 
 | #include <linux/err.h> | 
 | #include <linux/string.h> | 
 | #include <linux/of.h> | 
 | #include <linux/of_address.h> | 
 |  | 
 | struct clkgen_data { | 
 | 	unsigned long flags; | 
 | 	bool mode; | 
 | }; | 
 |  | 
 | struct flexgen { | 
 | 	struct clk_hw hw; | 
 |  | 
 | 	/* Crossbar */ | 
 | 	struct clk_mux mux; | 
 | 	/* Pre-divisor's gate */ | 
 | 	struct clk_gate pgate; | 
 | 	/* Pre-divisor */ | 
 | 	struct clk_divider pdiv; | 
 | 	/* Final divisor's gate */ | 
 | 	struct clk_gate fgate; | 
 | 	/* Final divisor */ | 
 | 	struct clk_divider fdiv; | 
 | 	/* Asynchronous mode control */ | 
 | 	struct clk_gate sync; | 
 | 	/* hw control flags */ | 
 | 	bool control_mode; | 
 | }; | 
 |  | 
 | #define to_flexgen(_hw) container_of(_hw, struct flexgen, hw) | 
 | #define to_clk_gate(_hw) container_of(_hw, struct clk_gate, hw) | 
 |  | 
 | static int flexgen_enable(struct clk_hw *hw) | 
 | { | 
 | 	struct flexgen *flexgen = to_flexgen(hw); | 
 | 	struct clk_hw *pgate_hw = &flexgen->pgate.hw; | 
 | 	struct clk_hw *fgate_hw = &flexgen->fgate.hw; | 
 |  | 
 | 	__clk_hw_set_clk(pgate_hw, hw); | 
 | 	__clk_hw_set_clk(fgate_hw, hw); | 
 |  | 
 | 	clk_gate_ops.enable(pgate_hw); | 
 |  | 
 | 	clk_gate_ops.enable(fgate_hw); | 
 |  | 
 | 	pr_debug("%s: flexgen output enabled\n", clk_hw_get_name(hw)); | 
 | 	return 0; | 
 | } | 
 |  | 
 | static void flexgen_disable(struct clk_hw *hw) | 
 | { | 
 | 	struct flexgen *flexgen = to_flexgen(hw); | 
 | 	struct clk_hw *fgate_hw = &flexgen->fgate.hw; | 
 |  | 
 | 	/* disable only the final gate */ | 
 | 	__clk_hw_set_clk(fgate_hw, hw); | 
 |  | 
 | 	clk_gate_ops.disable(fgate_hw); | 
 |  | 
 | 	pr_debug("%s: flexgen output disabled\n", clk_hw_get_name(hw)); | 
 | } | 
 |  | 
 | static int flexgen_is_enabled(struct clk_hw *hw) | 
 | { | 
 | 	struct flexgen *flexgen = to_flexgen(hw); | 
 | 	struct clk_hw *fgate_hw = &flexgen->fgate.hw; | 
 |  | 
 | 	__clk_hw_set_clk(fgate_hw, hw); | 
 |  | 
 | 	if (!clk_gate_ops.is_enabled(fgate_hw)) | 
 | 		return 0; | 
 |  | 
 | 	return 1; | 
 | } | 
 |  | 
 | static u8 flexgen_get_parent(struct clk_hw *hw) | 
 | { | 
 | 	struct flexgen *flexgen = to_flexgen(hw); | 
 | 	struct clk_hw *mux_hw = &flexgen->mux.hw; | 
 |  | 
 | 	__clk_hw_set_clk(mux_hw, hw); | 
 |  | 
 | 	return clk_mux_ops.get_parent(mux_hw); | 
 | } | 
 |  | 
 | static int flexgen_set_parent(struct clk_hw *hw, u8 index) | 
 | { | 
 | 	struct flexgen *flexgen = to_flexgen(hw); | 
 | 	struct clk_hw *mux_hw = &flexgen->mux.hw; | 
 |  | 
 | 	__clk_hw_set_clk(mux_hw, hw); | 
 |  | 
 | 	return clk_mux_ops.set_parent(mux_hw, index); | 
 | } | 
 |  | 
 | static inline unsigned long | 
 | clk_best_div(unsigned long parent_rate, unsigned long rate) | 
 | { | 
 | 	return parent_rate / rate + ((rate > (2*(parent_rate % rate))) ? 0 : 1); | 
 | } | 
 |  | 
 | static long flexgen_round_rate(struct clk_hw *hw, unsigned long rate, | 
 | 				   unsigned long *prate) | 
 | { | 
 | 	unsigned long div; | 
 |  | 
 | 	/* Round div according to exact prate and wished rate */ | 
 | 	div = clk_best_div(*prate, rate); | 
 |  | 
 | 	if (clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT) { | 
 | 		*prate = rate * div; | 
 | 		return rate; | 
 | 	} | 
 |  | 
 | 	return *prate / div; | 
 | } | 
 |  | 
 | static unsigned long flexgen_recalc_rate(struct clk_hw *hw, | 
 | 		unsigned long parent_rate) | 
 | { | 
 | 	struct flexgen *flexgen = to_flexgen(hw); | 
 | 	struct clk_hw *pdiv_hw = &flexgen->pdiv.hw; | 
 | 	struct clk_hw *fdiv_hw = &flexgen->fdiv.hw; | 
 | 	unsigned long mid_rate; | 
 |  | 
 | 	__clk_hw_set_clk(pdiv_hw, hw); | 
 | 	__clk_hw_set_clk(fdiv_hw, hw); | 
 |  | 
 | 	mid_rate = clk_divider_ops.recalc_rate(pdiv_hw, parent_rate); | 
 |  | 
 | 	return clk_divider_ops.recalc_rate(fdiv_hw, mid_rate); | 
 | } | 
 |  | 
 | static int flexgen_set_rate(struct clk_hw *hw, unsigned long rate, | 
 | 				unsigned long parent_rate) | 
 | { | 
 | 	struct flexgen *flexgen = to_flexgen(hw); | 
 | 	struct clk_hw *pdiv_hw = &flexgen->pdiv.hw; | 
 | 	struct clk_hw *fdiv_hw = &flexgen->fdiv.hw; | 
 | 	struct clk_hw *sync_hw = &flexgen->sync.hw; | 
 | 	struct clk_gate *config = to_clk_gate(sync_hw); | 
 | 	unsigned long div = 0; | 
 | 	int ret = 0; | 
 | 	u32 reg; | 
 |  | 
 | 	__clk_hw_set_clk(pdiv_hw, hw); | 
 | 	__clk_hw_set_clk(fdiv_hw, hw); | 
 |  | 
 | 	if (flexgen->control_mode) { | 
 | 		reg = readl(config->reg); | 
 | 		reg &= ~BIT(config->bit_idx); | 
 | 		writel(reg, config->reg); | 
 | 	} | 
 |  | 
 | 	div = clk_best_div(parent_rate, rate); | 
 |  | 
 | 	/* | 
 | 	* pdiv is mainly targeted for low freq results, while fdiv | 
 | 	* should be used for div <= 64. The other way round can | 
 | 	* lead to 'duty cycle' issues. | 
 | 	*/ | 
 |  | 
 | 	if (div <= 64) { | 
 | 		clk_divider_ops.set_rate(pdiv_hw, parent_rate, parent_rate); | 
 | 		ret = clk_divider_ops.set_rate(fdiv_hw, rate, rate * div); | 
 | 	} else { | 
 | 		clk_divider_ops.set_rate(fdiv_hw, parent_rate, parent_rate); | 
 | 		ret = clk_divider_ops.set_rate(pdiv_hw, rate, rate * div); | 
 | 	} | 
 |  | 
 | 	return ret; | 
 | } | 
 |  | 
 | static const struct clk_ops flexgen_ops = { | 
 | 	.enable = flexgen_enable, | 
 | 	.disable = flexgen_disable, | 
 | 	.is_enabled = flexgen_is_enabled, | 
 | 	.get_parent = flexgen_get_parent, | 
 | 	.set_parent = flexgen_set_parent, | 
 | 	.round_rate = flexgen_round_rate, | 
 | 	.recalc_rate = flexgen_recalc_rate, | 
 | 	.set_rate = flexgen_set_rate, | 
 | }; | 
 |  | 
 | static struct clk *clk_register_flexgen(const char *name, | 
 | 				const char **parent_names, u8 num_parents, | 
 | 				void __iomem *reg, spinlock_t *lock, u32 idx, | 
 | 				unsigned long flexgen_flags, bool mode) { | 
 | 	struct flexgen *fgxbar; | 
 | 	struct clk *clk; | 
 | 	struct clk_init_data init; | 
 | 	u32  xbar_shift; | 
 | 	void __iomem *xbar_reg, *fdiv_reg; | 
 |  | 
 | 	fgxbar = kzalloc(sizeof(struct flexgen), GFP_KERNEL); | 
 | 	if (!fgxbar) | 
 | 		return ERR_PTR(-ENOMEM); | 
 |  | 
 | 	init.name = name; | 
 | 	init.ops = &flexgen_ops; | 
 | 	init.flags = CLK_IS_BASIC | CLK_GET_RATE_NOCACHE | flexgen_flags; | 
 | 	init.parent_names = parent_names; | 
 | 	init.num_parents = num_parents; | 
 |  | 
 | 	xbar_reg = reg + 0x18 + (idx & ~0x3); | 
 | 	xbar_shift = (idx % 4) * 0x8; | 
 | 	fdiv_reg = reg + 0x164 + idx * 4; | 
 |  | 
 | 	/* Crossbar element config */ | 
 | 	fgxbar->mux.lock = lock; | 
 | 	fgxbar->mux.mask = BIT(6) - 1; | 
 | 	fgxbar->mux.reg = xbar_reg; | 
 | 	fgxbar->mux.shift = xbar_shift; | 
 | 	fgxbar->mux.table = NULL; | 
 |  | 
 |  | 
 | 	/* Pre-divider's gate config (in xbar register)*/ | 
 | 	fgxbar->pgate.lock = lock; | 
 | 	fgxbar->pgate.reg = xbar_reg; | 
 | 	fgxbar->pgate.bit_idx = xbar_shift + 6; | 
 |  | 
 | 	/* Pre-divider config */ | 
 | 	fgxbar->pdiv.lock = lock; | 
 | 	fgxbar->pdiv.reg = reg + 0x58 + idx * 4; | 
 | 	fgxbar->pdiv.width = 10; | 
 |  | 
 | 	/* Final divider's gate config */ | 
 | 	fgxbar->fgate.lock = lock; | 
 | 	fgxbar->fgate.reg = fdiv_reg; | 
 | 	fgxbar->fgate.bit_idx = 6; | 
 |  | 
 | 	/* Final divider config */ | 
 | 	fgxbar->fdiv.lock = lock; | 
 | 	fgxbar->fdiv.reg = fdiv_reg; | 
 | 	fgxbar->fdiv.width = 6; | 
 |  | 
 | 	/* Final divider sync config */ | 
 | 	fgxbar->sync.lock = lock; | 
 | 	fgxbar->sync.reg = fdiv_reg; | 
 | 	fgxbar->sync.bit_idx = 7; | 
 |  | 
 | 	fgxbar->control_mode = mode; | 
 |  | 
 | 	fgxbar->hw.init = &init; | 
 |  | 
 | 	clk = clk_register(NULL, &fgxbar->hw); | 
 | 	if (IS_ERR(clk)) | 
 | 		kfree(fgxbar); | 
 | 	else | 
 | 		pr_debug("%s: parent %s rate %u\n", | 
 | 			__clk_get_name(clk), | 
 | 			__clk_get_name(clk_get_parent(clk)), | 
 | 			(unsigned int)clk_get_rate(clk)); | 
 | 	return clk; | 
 | } | 
 |  | 
 | static const char ** __init flexgen_get_parents(struct device_node *np, | 
 | 						       int *num_parents) | 
 | { | 
 | 	const char **parents; | 
 | 	unsigned int nparents; | 
 |  | 
 | 	nparents = of_clk_get_parent_count(np); | 
 | 	if (WARN_ON(!nparents)) | 
 | 		return NULL; | 
 |  | 
 | 	parents = kcalloc(nparents, sizeof(const char *), GFP_KERNEL); | 
 | 	if (!parents) | 
 | 		return NULL; | 
 |  | 
 | 	*num_parents = of_clk_parent_fill(np, parents, nparents); | 
 |  | 
 | 	return parents; | 
 | } | 
 |  | 
 | static const struct clkgen_data clkgen_audio = { | 
 | 	.flags = CLK_SET_RATE_PARENT, | 
 | }; | 
 |  | 
 | static const struct clkgen_data clkgen_video = { | 
 | 	.flags = CLK_SET_RATE_PARENT, | 
 | 	.mode = 1, | 
 | }; | 
 |  | 
 | static const struct of_device_id flexgen_of_match[] = { | 
 | 	{ | 
 | 		.compatible = "st,flexgen-audio", | 
 | 		.data = &clkgen_audio, | 
 | 	}, | 
 | 	{ | 
 | 		.compatible = "st,flexgen-video", | 
 | 		.data = &clkgen_video, | 
 | 	}, | 
 | 	{} | 
 | }; | 
 |  | 
 | static void __init st_of_flexgen_setup(struct device_node *np) | 
 | { | 
 | 	struct device_node *pnode; | 
 | 	void __iomem *reg; | 
 | 	struct clk_onecell_data *clk_data; | 
 | 	const char **parents; | 
 | 	int num_parents, i; | 
 | 	spinlock_t *rlock = NULL; | 
 | 	const struct of_device_id *match; | 
 | 	struct clkgen_data *data = NULL; | 
 | 	unsigned long flex_flags = 0; | 
 | 	int ret; | 
 | 	bool clk_mode = 0; | 
 |  | 
 | 	pnode = of_get_parent(np); | 
 | 	if (!pnode) | 
 | 		return; | 
 |  | 
 | 	reg = of_iomap(pnode, 0); | 
 | 	if (!reg) | 
 | 		return; | 
 |  | 
 | 	parents = flexgen_get_parents(np, &num_parents); | 
 | 	if (!parents) { | 
 | 		iounmap(reg); | 
 | 		return; | 
 | 	} | 
 |  | 
 | 	match = of_match_node(flexgen_of_match, np); | 
 | 	if (match) { | 
 | 		data = (struct clkgen_data *)match->data; | 
 | 		flex_flags = data->flags; | 
 | 		clk_mode = data->mode; | 
 | 	} | 
 |  | 
 | 	clk_data = kzalloc(sizeof(*clk_data), GFP_KERNEL); | 
 | 	if (!clk_data) | 
 | 		goto err; | 
 |  | 
 | 	ret = of_property_count_strings(np, "clock-output-names"); | 
 | 	if (ret <= 0) { | 
 | 		pr_err("%s: Failed to get number of output clocks (%d)", | 
 | 				__func__, clk_data->clk_num); | 
 | 		goto err; | 
 | 	} | 
 | 	clk_data->clk_num = ret; | 
 |  | 
 | 	clk_data->clks = kcalloc(clk_data->clk_num, sizeof(struct clk *), | 
 | 			GFP_KERNEL); | 
 | 	if (!clk_data->clks) | 
 | 		goto err; | 
 |  | 
 | 	rlock = kzalloc(sizeof(spinlock_t), GFP_KERNEL); | 
 | 	if (!rlock) | 
 | 		goto err; | 
 |  | 
 | 	spin_lock_init(rlock); | 
 |  | 
 | 	for (i = 0; i < clk_data->clk_num; i++) { | 
 | 		struct clk *clk; | 
 | 		const char *clk_name; | 
 |  | 
 | 		if (of_property_read_string_index(np, "clock-output-names", | 
 | 						  i, &clk_name)) { | 
 | 			break; | 
 | 		} | 
 |  | 
 | 		of_clk_detect_critical(np, i, &flex_flags); | 
 |  | 
 | 		/* | 
 | 		 * If we read an empty clock name then the output is unused | 
 | 		 */ | 
 | 		if (*clk_name == '\0') | 
 | 			continue; | 
 |  | 
 | 		clk = clk_register_flexgen(clk_name, parents, num_parents, | 
 | 					   reg, rlock, i, flex_flags, clk_mode); | 
 |  | 
 | 		if (IS_ERR(clk)) | 
 | 			goto err; | 
 |  | 
 | 		clk_data->clks[i] = clk; | 
 | 	} | 
 |  | 
 | 	kfree(parents); | 
 | 	of_clk_add_provider(np, of_clk_src_onecell_get, clk_data); | 
 |  | 
 | 	return; | 
 |  | 
 | err: | 
 | 	iounmap(reg); | 
 | 	if (clk_data) | 
 | 		kfree(clk_data->clks); | 
 | 	kfree(clk_data); | 
 | 	kfree(parents); | 
 | 	kfree(rlock); | 
 | } | 
 | CLK_OF_DECLARE(flexgen, "st,flexgen", st_of_flexgen_setup); |