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1// SPDX-License-Identifier: GPL-2.02/*3 * Zynq UltraScale+ MPSoC mux4 *5 *  Copyright (C) 2016-2018 Xilinx6 */7 8#include <linux/clk-provider.h>9#include <linux/slab.h>10#include "clk-zynqmp.h"11 12/*13 * DOC: basic adjustable multiplexer clock that cannot gate14 *15 * Traits of this clock:16 * prepare - clk_prepare only ensures that parents are prepared17 * enable - clk_enable only ensures that parents are enabled18 * rate - rate is only affected by parent switching.  No clk_set_rate support19 * parent - parent is adjustable through clk_set_parent20 */21 22/**23 * struct zynqmp_clk_mux - multiplexer clock24 *25 * @hw:		handle between common and hardware-specific interfaces26 * @flags:	hardware-specific flags27 * @clk_id:	Id of clock28 */29struct zynqmp_clk_mux {30	struct clk_hw hw;31	u8 flags;32	u32 clk_id;33};34 35#define to_zynqmp_clk_mux(_hw) container_of(_hw, struct zynqmp_clk_mux, hw)36 37/**38 * zynqmp_clk_mux_get_parent() - Get parent of clock39 * @hw:		handle between common and hardware-specific interfaces40 *41 * Return: Parent index on success or number of parents in case of error42 */43static u8 zynqmp_clk_mux_get_parent(struct clk_hw *hw)44{45	struct zynqmp_clk_mux *mux = to_zynqmp_clk_mux(hw);46	const char *clk_name = clk_hw_get_name(hw);47	u32 clk_id = mux->clk_id;48	u32 val;49	int ret;50 51	ret = zynqmp_pm_clock_getparent(clk_id, &val);52 53	if (ret) {54		pr_debug("%s() getparent failed for clock: %s, ret = %d\n",55			 __func__, clk_name, ret);56		/*57		 * clk_core_get_parent_by_index() takes num_parents as incorrect58		 * index which is exactly what I want to return here59		 */60		return clk_hw_get_num_parents(hw);61	}62 63	return val;64}65 66/**67 * zynqmp_clk_mux_set_parent() - Set parent of clock68 * @hw:		handle between common and hardware-specific interfaces69 * @index:	Parent index70 *71 * Return: 0 on success else error+reason72 */73static int zynqmp_clk_mux_set_parent(struct clk_hw *hw, u8 index)74{75	struct zynqmp_clk_mux *mux = to_zynqmp_clk_mux(hw);76	const char *clk_name = clk_hw_get_name(hw);77	u32 clk_id = mux->clk_id;78	int ret;79 80	ret = zynqmp_pm_clock_setparent(clk_id, index);81 82	if (ret)83		pr_debug("%s() set parent failed for clock: %s, ret = %d\n",84			 __func__, clk_name, ret);85 86	return ret;87}88 89static const struct clk_ops zynqmp_clk_mux_ops = {90	.get_parent = zynqmp_clk_mux_get_parent,91	.set_parent = zynqmp_clk_mux_set_parent,92	.determine_rate = __clk_mux_determine_rate_closest,93};94 95static const struct clk_ops zynqmp_clk_mux_ro_ops = {96	.get_parent = zynqmp_clk_mux_get_parent,97};98 99static inline unsigned long zynqmp_clk_map_mux_ccf_flags(100				       const u32 zynqmp_type_flag)101{102	unsigned long ccf_flag = 0;103 104	if (zynqmp_type_flag & ZYNQMP_CLK_MUX_INDEX_ONE)105		ccf_flag |= CLK_MUX_INDEX_ONE;106	if (zynqmp_type_flag & ZYNQMP_CLK_MUX_INDEX_BIT)107		ccf_flag |= CLK_MUX_INDEX_BIT;108	if (zynqmp_type_flag & ZYNQMP_CLK_MUX_HIWORD_MASK)109		ccf_flag |= CLK_MUX_HIWORD_MASK;110	if (zynqmp_type_flag & ZYNQMP_CLK_MUX_READ_ONLY)111		ccf_flag |= CLK_MUX_READ_ONLY;112	if (zynqmp_type_flag & ZYNQMP_CLK_MUX_ROUND_CLOSEST)113		ccf_flag |= CLK_MUX_ROUND_CLOSEST;114	if (zynqmp_type_flag & ZYNQMP_CLK_MUX_BIG_ENDIAN)115		ccf_flag |= CLK_MUX_BIG_ENDIAN;116 117	return ccf_flag;118}119 120/**121 * zynqmp_clk_register_mux() - Register a mux table with the clock122 *			       framework123 * @name:		Name of this clock124 * @clk_id:		Id of this clock125 * @parents:		Name of this clock's parents126 * @num_parents:	Number of parents127 * @nodes:		Clock topology node128 *129 * Return: clock hardware of the registered clock mux130 */131struct clk_hw *zynqmp_clk_register_mux(const char *name, u32 clk_id,132				       const char * const *parents,133				       u8 num_parents,134				       const struct clock_topology *nodes)135{136	struct zynqmp_clk_mux *mux;137	struct clk_hw *hw;138	struct clk_init_data init;139	int ret;140 141	mux = kzalloc(sizeof(*mux), GFP_KERNEL);142	if (!mux)143		return ERR_PTR(-ENOMEM);144 145	init.name = name;146	if (nodes->type_flag & CLK_MUX_READ_ONLY)147		init.ops = &zynqmp_clk_mux_ro_ops;148	else149		init.ops = &zynqmp_clk_mux_ops;150 151	init.flags = zynqmp_clk_map_common_ccf_flags(nodes->flag);152 153	init.parent_names = parents;154	init.num_parents = num_parents;155	mux->flags = zynqmp_clk_map_mux_ccf_flags(nodes->type_flag);156	mux->hw.init = &init;157	mux->clk_id = clk_id;158 159	hw = &mux->hw;160	ret = clk_hw_register(NULL, hw);161	if (ret) {162		kfree(mux);163		hw = ERR_PTR(ret);164	}165 166	return hw;167}168