xref: /openbmc/linux/drivers/clk/qcom/clk-rpmh.c (revision 8fdf9062)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2018, The Linux Foundation. All rights reserved.
4  */
5 
6 #include <linux/clk-provider.h>
7 #include <linux/err.h>
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/of.h>
11 #include <linux/of_device.h>
12 #include <linux/platform_device.h>
13 #include <soc/qcom/cmd-db.h>
14 #include <soc/qcom/rpmh.h>
15 
16 #include <dt-bindings/clock/qcom,rpmh.h>
17 
18 #define CLK_RPMH_ARC_EN_OFFSET		0
19 #define CLK_RPMH_VRM_EN_OFFSET		4
20 
21 /**
22  * struct clk_rpmh - individual rpmh clock data structure
23  * @hw:			handle between common and hardware-specific interfaces
24  * @res_name:		resource name for the rpmh clock
25  * @div:		clock divider to compute the clock rate
26  * @res_addr:		base address of the rpmh resource within the RPMh
27  * @res_on_val:		rpmh clock enable value
28  * @state:		rpmh clock requested state
29  * @aggr_state:		rpmh clock aggregated state
30  * @last_sent_aggr_state: rpmh clock last aggr state sent to RPMh
31  * @valid_state_mask:	mask to determine the state of the rpmh clock
32  * @dev:		device to which it is attached
33  * @peer:		pointer to the clock rpmh sibling
34  */
35 struct clk_rpmh {
36 	struct clk_hw hw;
37 	const char *res_name;
38 	u8 div;
39 	u32 res_addr;
40 	u32 res_on_val;
41 	u32 state;
42 	u32 aggr_state;
43 	u32 last_sent_aggr_state;
44 	u32 valid_state_mask;
45 	struct device *dev;
46 	struct clk_rpmh *peer;
47 };
48 
49 struct clk_rpmh_desc {
50 	struct clk_hw **clks;
51 	size_t num_clks;
52 };
53 
54 static DEFINE_MUTEX(rpmh_clk_lock);
55 
56 #define __DEFINE_CLK_RPMH(_platform, _name, _name_active, _res_name,	\
57 			  _res_en_offset, _res_on, _div)		\
58 	static struct clk_rpmh _platform##_##_name_active;		\
59 	static struct clk_rpmh _platform##_##_name = {			\
60 		.res_name = _res_name,					\
61 		.res_addr = _res_en_offset,				\
62 		.res_on_val = _res_on,					\
63 		.div = _div,						\
64 		.peer = &_platform##_##_name_active,			\
65 		.valid_state_mask = (BIT(RPMH_WAKE_ONLY_STATE) |	\
66 				      BIT(RPMH_ACTIVE_ONLY_STATE) |	\
67 				      BIT(RPMH_SLEEP_STATE)),		\
68 		.hw.init = &(struct clk_init_data){			\
69 			.ops = &clk_rpmh_ops,				\
70 			.name = #_name,					\
71 			.parent_names = (const char *[]){ "xo_board" },	\
72 			.num_parents = 1,				\
73 		},							\
74 	};								\
75 	static struct clk_rpmh _platform##_##_name_active = {		\
76 		.res_name = _res_name,					\
77 		.res_addr = _res_en_offset,				\
78 		.res_on_val = _res_on,					\
79 		.div = _div,						\
80 		.peer = &_platform##_##_name,				\
81 		.valid_state_mask = (BIT(RPMH_WAKE_ONLY_STATE) |	\
82 					BIT(RPMH_ACTIVE_ONLY_STATE)),	\
83 		.hw.init = &(struct clk_init_data){			\
84 			.ops = &clk_rpmh_ops,				\
85 			.name = #_name_active,				\
86 			.parent_names = (const char *[]){ "xo_board" },	\
87 			.num_parents = 1,				\
88 		},							\
89 	}
90 
91 #define DEFINE_CLK_RPMH_ARC(_platform, _name, _name_active, _res_name,	\
92 			    _res_on, _div)				\
93 	__DEFINE_CLK_RPMH(_platform, _name, _name_active, _res_name,	\
94 			  CLK_RPMH_ARC_EN_OFFSET, _res_on, _div)
95 
96 #define DEFINE_CLK_RPMH_VRM(_platform, _name, _name_active, _res_name,	\
97 				_div)					\
98 	__DEFINE_CLK_RPMH(_platform, _name, _name_active, _res_name,	\
99 			  CLK_RPMH_VRM_EN_OFFSET, 1, _div)
100 
101 static inline struct clk_rpmh *to_clk_rpmh(struct clk_hw *_hw)
102 {
103 	return container_of(_hw, struct clk_rpmh, hw);
104 }
105 
106 static inline bool has_state_changed(struct clk_rpmh *c, u32 state)
107 {
108 	return (c->last_sent_aggr_state & BIT(state))
109 		!= (c->aggr_state & BIT(state));
110 }
111 
112 static int clk_rpmh_send_aggregate_command(struct clk_rpmh *c)
113 {
114 	struct tcs_cmd cmd = { 0 };
115 	u32 cmd_state, on_val;
116 	enum rpmh_state state = RPMH_SLEEP_STATE;
117 	int ret;
118 
119 	cmd.addr = c->res_addr;
120 	cmd_state = c->aggr_state;
121 	on_val = c->res_on_val;
122 
123 	for (; state <= RPMH_ACTIVE_ONLY_STATE; state++) {
124 		if (has_state_changed(c, state)) {
125 			if (cmd_state & BIT(state))
126 				cmd.data = on_val;
127 
128 			ret = rpmh_write_async(c->dev, state, &cmd, 1);
129 			if (ret) {
130 				dev_err(c->dev, "set %s state of %s failed: (%d)\n",
131 					!state ? "sleep" :
132 					state == RPMH_WAKE_ONLY_STATE	?
133 					"wake" : "active", c->res_name, ret);
134 				return ret;
135 			}
136 		}
137 	}
138 
139 	c->last_sent_aggr_state = c->aggr_state;
140 	c->peer->last_sent_aggr_state =  c->last_sent_aggr_state;
141 
142 	return 0;
143 }
144 
145 /*
146  * Update state and aggregate state values based on enable value.
147  */
148 static int clk_rpmh_aggregate_state_send_command(struct clk_rpmh *c,
149 						bool enable)
150 {
151 	int ret;
152 
153 	/* Nothing required to be done if already off or on */
154 	if (enable == c->state)
155 		return 0;
156 
157 	c->state = enable ? c->valid_state_mask : 0;
158 	c->aggr_state = c->state | c->peer->state;
159 	c->peer->aggr_state = c->aggr_state;
160 
161 	ret = clk_rpmh_send_aggregate_command(c);
162 	if (!ret)
163 		return 0;
164 
165 	if (ret && enable)
166 		c->state = 0;
167 	else if (ret)
168 		c->state = c->valid_state_mask;
169 
170 	WARN(1, "clk: %s failed to %s\n", c->res_name,
171 	     enable ? "enable" : "disable");
172 	return ret;
173 }
174 
175 static int clk_rpmh_prepare(struct clk_hw *hw)
176 {
177 	struct clk_rpmh *c = to_clk_rpmh(hw);
178 	int ret = 0;
179 
180 	mutex_lock(&rpmh_clk_lock);
181 	ret = clk_rpmh_aggregate_state_send_command(c, true);
182 	mutex_unlock(&rpmh_clk_lock);
183 
184 	return ret;
185 };
186 
187 static void clk_rpmh_unprepare(struct clk_hw *hw)
188 {
189 	struct clk_rpmh *c = to_clk_rpmh(hw);
190 
191 	mutex_lock(&rpmh_clk_lock);
192 	clk_rpmh_aggregate_state_send_command(c, false);
193 	mutex_unlock(&rpmh_clk_lock);
194 };
195 
196 static unsigned long clk_rpmh_recalc_rate(struct clk_hw *hw,
197 					unsigned long prate)
198 {
199 	struct clk_rpmh *r = to_clk_rpmh(hw);
200 
201 	/*
202 	 * RPMh clocks have a fixed rate. Return static rate.
203 	 */
204 	return prate / r->div;
205 }
206 
207 static const struct clk_ops clk_rpmh_ops = {
208 	.prepare	= clk_rpmh_prepare,
209 	.unprepare	= clk_rpmh_unprepare,
210 	.recalc_rate	= clk_rpmh_recalc_rate,
211 };
212 
213 /* Resource name must match resource id present in cmd-db. */
214 DEFINE_CLK_RPMH_ARC(sdm845, bi_tcxo, bi_tcxo_ao, "xo.lvl", 0x3, 2);
215 DEFINE_CLK_RPMH_VRM(sdm845, ln_bb_clk2, ln_bb_clk2_ao, "lnbclka2", 2);
216 DEFINE_CLK_RPMH_VRM(sdm845, ln_bb_clk3, ln_bb_clk3_ao, "lnbclka3", 2);
217 DEFINE_CLK_RPMH_VRM(sdm845, rf_clk1, rf_clk1_ao, "rfclka1", 1);
218 DEFINE_CLK_RPMH_VRM(sdm845, rf_clk2, rf_clk2_ao, "rfclka2", 1);
219 DEFINE_CLK_RPMH_VRM(sdm845, rf_clk3, rf_clk3_ao, "rfclka3", 1);
220 
221 static struct clk_hw *sdm845_rpmh_clocks[] = {
222 	[RPMH_CXO_CLK]		= &sdm845_bi_tcxo.hw,
223 	[RPMH_CXO_CLK_A]	= &sdm845_bi_tcxo_ao.hw,
224 	[RPMH_LN_BB_CLK2]	= &sdm845_ln_bb_clk2.hw,
225 	[RPMH_LN_BB_CLK2_A]	= &sdm845_ln_bb_clk2_ao.hw,
226 	[RPMH_LN_BB_CLK3]	= &sdm845_ln_bb_clk3.hw,
227 	[RPMH_LN_BB_CLK3_A]	= &sdm845_ln_bb_clk3_ao.hw,
228 	[RPMH_RF_CLK1]		= &sdm845_rf_clk1.hw,
229 	[RPMH_RF_CLK1_A]	= &sdm845_rf_clk1_ao.hw,
230 	[RPMH_RF_CLK2]		= &sdm845_rf_clk2.hw,
231 	[RPMH_RF_CLK2_A]	= &sdm845_rf_clk2_ao.hw,
232 	[RPMH_RF_CLK3]		= &sdm845_rf_clk3.hw,
233 	[RPMH_RF_CLK3_A]	= &sdm845_rf_clk3_ao.hw,
234 };
235 
236 static const struct clk_rpmh_desc clk_rpmh_sdm845 = {
237 	.clks = sdm845_rpmh_clocks,
238 	.num_clks = ARRAY_SIZE(sdm845_rpmh_clocks),
239 };
240 
241 static struct clk_hw *of_clk_rpmh_hw_get(struct of_phandle_args *clkspec,
242 					 void *data)
243 {
244 	struct clk_rpmh_desc *rpmh = data;
245 	unsigned int idx = clkspec->args[0];
246 
247 	if (idx >= rpmh->num_clks) {
248 		pr_err("%s: invalid index %u\n", __func__, idx);
249 		return ERR_PTR(-EINVAL);
250 	}
251 
252 	return rpmh->clks[idx];
253 }
254 
255 static int clk_rpmh_probe(struct platform_device *pdev)
256 {
257 	struct clk_hw **hw_clks;
258 	struct clk_rpmh *rpmh_clk;
259 	const struct clk_rpmh_desc *desc;
260 	int ret, i;
261 
262 	desc = of_device_get_match_data(&pdev->dev);
263 	if (!desc)
264 		return -ENODEV;
265 
266 	hw_clks = desc->clks;
267 
268 	for (i = 0; i < desc->num_clks; i++) {
269 		u32 res_addr;
270 
271 		rpmh_clk = to_clk_rpmh(hw_clks[i]);
272 		res_addr = cmd_db_read_addr(rpmh_clk->res_name);
273 		if (!res_addr) {
274 			dev_err(&pdev->dev, "missing RPMh resource address for %s\n",
275 				rpmh_clk->res_name);
276 			return -ENODEV;
277 		}
278 		rpmh_clk->res_addr += res_addr;
279 		rpmh_clk->dev = &pdev->dev;
280 
281 		ret = devm_clk_hw_register(&pdev->dev, hw_clks[i]);
282 		if (ret) {
283 			dev_err(&pdev->dev, "failed to register %s\n",
284 				hw_clks[i]->init->name);
285 			return ret;
286 		}
287 	}
288 
289 	/* typecast to silence compiler warning */
290 	ret = devm_of_clk_add_hw_provider(&pdev->dev, of_clk_rpmh_hw_get,
291 					  (void *)desc);
292 	if (ret) {
293 		dev_err(&pdev->dev, "Failed to add clock provider\n");
294 		return ret;
295 	}
296 
297 	dev_dbg(&pdev->dev, "Registered RPMh clocks\n");
298 
299 	return 0;
300 }
301 
302 static const struct of_device_id clk_rpmh_match_table[] = {
303 	{ .compatible = "qcom,sdm845-rpmh-clk", .data = &clk_rpmh_sdm845},
304 	{ }
305 };
306 MODULE_DEVICE_TABLE(of, clk_rpmh_match_table);
307 
308 static struct platform_driver clk_rpmh_driver = {
309 	.probe		= clk_rpmh_probe,
310 	.driver		= {
311 		.name	= "clk-rpmh",
312 		.of_match_table = clk_rpmh_match_table,
313 	},
314 };
315 
316 static int __init clk_rpmh_init(void)
317 {
318 	return platform_driver_register(&clk_rpmh_driver);
319 }
320 subsys_initcall(clk_rpmh_init);
321 
322 static void __exit clk_rpmh_exit(void)
323 {
324 	platform_driver_unregister(&clk_rpmh_driver);
325 }
326 module_exit(clk_rpmh_exit);
327 
328 MODULE_DESCRIPTION("QCOM RPMh Clock Driver");
329 MODULE_LICENSE("GPL v2");
330