gate.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * OMAP gate clock support
  4 *
  5 * Copyright (C) 2013 Texas Instruments, Inc.
  6 *
  7 * Tero Kristo <t-kristo@ti.com>
  8 */
  9
 10#include <linux/clk-provider.h>
 11#include <linux/slab.h>
 12#include <linux/io.h>
 13#include <linux/of.h>
 14#include <linux/of_address.h>
 15#include <linux/clk/ti.h>
 16
 17#include "clock.h"
 18
 19#undef pr_fmt
 20#define pr_fmt(fmt) "%s: " fmt, __func__
 21
 22static int omap36xx_gate_clk_enable_with_hsdiv_restore(struct clk_hw *clk);
 23
 24static const struct clk_ops omap_gate_clkdm_clk_ops = {
 25	.init		= &omap2_init_clk_clkdm,
 26	.enable		= &omap2_clkops_enable_clkdm,
 27	.disable	= &omap2_clkops_disable_clkdm,
 28	.restore_context = clk_gate_restore_context,
 29};
 30
 31const struct clk_ops omap_gate_clk_ops = {
 32	.init		= &omap2_init_clk_clkdm,
 33	.enable		= &omap2_dflt_clk_enable,
 34	.disable	= &omap2_dflt_clk_disable,
 35	.is_enabled	= &omap2_dflt_clk_is_enabled,
 36	.restore_context = clk_gate_restore_context,
 37};
 38
 39static const struct clk_ops omap_gate_clk_hsdiv_restore_ops = {
 40	.init		= &omap2_init_clk_clkdm,
 41	.enable		= &omap36xx_gate_clk_enable_with_hsdiv_restore,
 42	.disable	= &omap2_dflt_clk_disable,
 43	.is_enabled	= &omap2_dflt_clk_is_enabled,
 44	.restore_context = clk_gate_restore_context,
 45};
 46
 47/**
 48 * omap36xx_gate_clk_enable_with_hsdiv_restore - enable clocks suffering
 49 *         from HSDivider PWRDN problem Implements Errata ID: i556.
 50 * @hw: DPLL output struct clk_hw
 51 *
 52 * 3630 only: dpll3_m3_ck, dpll4_m2_ck, dpll4_m3_ck, dpll4_m4_ck,
 53 * dpll4_m5_ck & dpll4_m6_ck dividers gets loaded with reset
 54 * valueafter their respective PWRDN bits are set.  Any dummy write
 55 * (Any other value different from the Read value) to the
 56 * corresponding CM_CLKSEL register will refresh the dividers.
 57 */
 58static int omap36xx_gate_clk_enable_with_hsdiv_restore(struct clk_hw *hw)
 59{
 60	struct clk_omap_divider *parent;
 61	struct clk_hw *parent_hw;
 62	u32 dummy_v, orig_v;
 63	int ret;
 64
 65	/* Clear PWRDN bit of HSDIVIDER */
 66	ret = omap2_dflt_clk_enable(hw);
 67
 68	/* Parent is the x2 node, get parent of parent for the m2 div */
 69	parent_hw = clk_hw_get_parent(clk_hw_get_parent(hw));
 70	parent = to_clk_omap_divider(parent_hw);
 71
 72	/* Restore the dividers */
 73	if (!ret) {
 74		orig_v = ti_clk_ll_ops->clk_readl(&parent->reg);
 75		dummy_v = orig_v;
 76
 77		/* Write any other value different from the Read value */
 78		dummy_v ^= (1 << parent->shift);
 79		ti_clk_ll_ops->clk_writel(dummy_v, &parent->reg);
 80
 81		/* Write the original divider */
 82		ti_clk_ll_ops->clk_writel(orig_v, &parent->reg);
 83	}
 84
 85	return ret;
 86}
 87
 88static struct clk *_register_gate(struct device_node *node, const char *name,
 89				  const char *parent_name, unsigned long flags,
 90				  struct clk_omap_reg *reg, u8 bit_idx,
 91				  u8 clk_gate_flags, const struct clk_ops *ops,
 92				  const struct clk_hw_omap_ops *hw_ops)
 93{
 94	struct clk_init_data init = { NULL };
 95	struct clk_hw_omap *clk_hw;
 96	struct clk *clk;
 97
 98	clk_hw = kzalloc(sizeof(*clk_hw), GFP_KERNEL);
 99	if (!clk_hw)
100		return ERR_PTR(-ENOMEM);
101
102	clk_hw->hw.init = &init;
103
104	init.name = name;
105	init.ops = ops;
106
107	memcpy(&clk_hw->enable_reg, reg, sizeof(*reg));
108	clk_hw->enable_bit = bit_idx;
109	clk_hw->ops = hw_ops;
110
111	clk_hw->flags = clk_gate_flags;
112
113	init.parent_names = &parent_name;
114	init.num_parents = 1;
115
116	init.flags = flags;
117
118	clk = of_ti_clk_register_omap_hw(node, &clk_hw->hw, name);
119
120	if (IS_ERR(clk))
121		kfree(clk_hw);
122
123	return clk;
124}
125
126static void __init _of_ti_gate_clk_setup(struct device_node *node,
127					 const struct clk_ops *ops,
128					 const struct clk_hw_omap_ops *hw_ops)
129{
130	struct clk *clk;
131	const char *parent_name;
132	struct clk_omap_reg reg;
133	const char *name;
134	u8 enable_bit = 0;
135	u32 flags = 0;
136	u8 clk_gate_flags = 0;
137
138	if (ops != &omap_gate_clkdm_clk_ops) {
139		if (ti_clk_get_reg_addr(node, 0, &reg))
140			return;
141
142		enable_bit = reg.bit;
143	}
144
145	if (of_clk_get_parent_count(node) != 1) {
146		pr_err("%pOFn must have 1 parent\n", node);
147		return;
148	}
149
150	parent_name = of_clk_get_parent_name(node, 0);
151
152	if (of_property_read_bool(node, "ti,set-rate-parent"))
153		flags |= CLK_SET_RATE_PARENT;
154
155	if (of_property_read_bool(node, "ti,set-bit-to-disable"))
156		clk_gate_flags |= INVERT_ENABLE;
157
158	name = ti_dt_clk_name(node);
159	clk = _register_gate(node, name, parent_name, flags, &reg,
160			     enable_bit, clk_gate_flags, ops, hw_ops);
161
162	if (!IS_ERR(clk))
163		of_clk_add_provider(node, of_clk_src_simple_get, clk);
164}
165
166static void __init
167_of_ti_composite_gate_clk_setup(struct device_node *node,
168				const struct clk_hw_omap_ops *hw_ops)
169{
170	struct clk_hw_omap *gate;
171
172	gate = kzalloc(sizeof(*gate), GFP_KERNEL);
173	if (!gate)
174		return;
175
176	if (ti_clk_get_reg_addr(node, 0, &gate->enable_reg))
177		goto cleanup;
178
179	gate->enable_bit = gate->enable_reg.bit;
180	gate->ops = hw_ops;
181
182	if (!ti_clk_add_component(node, &gate->hw, CLK_COMPONENT_TYPE_GATE))
183		return;
184
185cleanup:
186	kfree(gate);
187}
188
189static void __init
190of_ti_composite_no_wait_gate_clk_setup(struct device_node *node)
191{
192	_of_ti_composite_gate_clk_setup(node, NULL);
193}
194CLK_OF_DECLARE(ti_composite_no_wait_gate_clk, "ti,composite-no-wait-gate-clock",
195	       of_ti_composite_no_wait_gate_clk_setup);
196
197#if defined(CONFIG_ARCH_OMAP2) || defined(CONFIG_ARCH_OMAP3)
198static void __init of_ti_composite_interface_clk_setup(struct device_node *node)
199{
200	_of_ti_composite_gate_clk_setup(node, &clkhwops_iclk_wait);
201}
202CLK_OF_DECLARE(ti_composite_interface_clk, "ti,composite-interface-clock",
203	       of_ti_composite_interface_clk_setup);
204#endif
205
206static void __init of_ti_composite_gate_clk_setup(struct device_node *node)
207{
208	_of_ti_composite_gate_clk_setup(node, &clkhwops_wait);
209}
210CLK_OF_DECLARE(ti_composite_gate_clk, "ti,composite-gate-clock",
211	       of_ti_composite_gate_clk_setup);
212
213
214static void __init of_ti_clkdm_gate_clk_setup(struct device_node *node)
215{
216	_of_ti_gate_clk_setup(node, &omap_gate_clkdm_clk_ops, NULL);
217}
218CLK_OF_DECLARE(ti_clkdm_gate_clk, "ti,clkdm-gate-clock",
219	       of_ti_clkdm_gate_clk_setup);
220
221static void __init of_ti_hsdiv_gate_clk_setup(struct device_node *node)
222{
223	_of_ti_gate_clk_setup(node, &omap_gate_clk_hsdiv_restore_ops,
224			      &clkhwops_wait);
225}
226CLK_OF_DECLARE(ti_hsdiv_gate_clk, "ti,hsdiv-gate-clock",
227	       of_ti_hsdiv_gate_clk_setup);
228
229static void __init of_ti_gate_clk_setup(struct device_node *node)
230{
231	_of_ti_gate_clk_setup(node, &omap_gate_clk_ops, NULL);
232}
233CLK_OF_DECLARE(ti_gate_clk, "ti,gate-clock", of_ti_gate_clk_setup);
234
235static void __init of_ti_wait_gate_clk_setup(struct device_node *node)
236{
237	_of_ti_gate_clk_setup(node, &omap_gate_clk_ops, &clkhwops_wait);
238}
239CLK_OF_DECLARE(ti_wait_gate_clk, "ti,wait-gate-clock",
240	       of_ti_wait_gate_clk_setup);
241
242#ifdef CONFIG_ARCH_OMAP3
243static void __init of_ti_am35xx_gate_clk_setup(struct device_node *node)
244{
245	_of_ti_gate_clk_setup(node, &omap_gate_clk_ops,
246			      &clkhwops_am35xx_ipss_module_wait);
247}
248CLK_OF_DECLARE(ti_am35xx_gate_clk, "ti,am35xx-gate-clock",
249	       of_ti_am35xx_gate_clk_setup);
250
251static void __init of_ti_dss_gate_clk_setup(struct device_node *node)
252{
253	_of_ti_gate_clk_setup(node, &omap_gate_clk_ops,
254			      &clkhwops_omap3430es2_dss_usbhost_wait);
255}
256CLK_OF_DECLARE(ti_dss_gate_clk, "ti,dss-gate-clock",
257	       of_ti_dss_gate_clk_setup);
258#endif