xref: /netbsd-src/sys/arch/arm/rockchip/rk_cru_arm.c (revision 4fb053697f9d68002b95c174d5a1bc8eedbd6977)
1 /* $NetBSD: rk_cru_arm.c,v 1.5 2022/08/23 05:39:06 ryo Exp $ */
2 
3 /*-
4  * Copyright (c) 2018 Jared McNeill <jmcneill@invisible.ca>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: rk_cru_arm.c,v 1.5 2022/08/23 05:39:06 ryo Exp $");
31 
32 #include <sys/param.h>
33 #include <sys/bus.h>
34 
35 #include <dev/clk/clk_backend.h>
36 
37 #include <arm/rockchip/rk_cru.h>
38 
39 u_int
rk_cru_arm_get_rate(struct rk_cru_softc * sc,struct rk_cru_clk * clk)40 rk_cru_arm_get_rate(struct rk_cru_softc *sc,
41     struct rk_cru_clk *clk)
42 {
43 	struct rk_cru_arm *arm = &clk->u.arm;
44 	struct clk *clkp, *clkp_parent;
45 
46 	KASSERT(clk->type == RK_CRU_ARM);
47 
48 	clkp = &clk->base;
49 	clkp_parent = clk_get_parent(clkp);
50 	if (clkp_parent == NULL)
51 		return 0;
52 
53 	const u_int fref = clk_get_rate(clkp_parent);
54 	if (fref == 0)
55 		return 0;
56 
57 	const uint32_t val = CRU_READ(sc, arm->divs[0].reg);
58 	const u_int div = __SHIFTOUT(val, arm->divs[0].mask) + 1;
59 
60 	return fref / div;
61 }
62 
63 static int
rk_cru_arm_set_rate_rates(struct rk_cru_softc * sc,struct rk_cru_clk * clk,u_int rate)64 rk_cru_arm_set_rate_rates(struct rk_cru_softc *sc,
65     struct rk_cru_clk *clk, u_int rate)
66 {
67 	struct rk_cru_arm *arm = &clk->u.arm;
68 	struct rk_cru_clk *main_parent, *alt_parent;
69 	const struct rk_cru_arm_rate *arm_rate = NULL;
70 	int error;
71 
72 	KASSERT(clk->type == RK_CRU_ARM);
73 
74 	if (arm->rates == NULL || rate == 0)
75 		return EIO;
76 
77 	for (int i = 0; i < arm->nrates; i++)
78 		if (arm->rates[i].rate == rate) {
79 			arm_rate = &arm->rates[i];
80 			break;
81 		}
82 	if (arm_rate == NULL)
83 		return EINVAL;
84 
85 	main_parent = rk_cru_clock_find(sc, arm->parents[arm->mux_main]);
86 	alt_parent = rk_cru_clock_find(sc, arm->parents[arm->mux_alt]);
87 	if (main_parent == NULL || alt_parent == NULL) {
88 		device_printf(sc->sc_dev, "couldn't get clock parents\n");
89 		return ENXIO;
90 	}
91 
92 	error = rk_cru_arm_set_parent(sc, clk, arm->parents[arm->mux_alt]);
93 	if (error != 0)
94 		return error;
95 
96 	const u_int parent_rate = arm_rate->rate / arm_rate->div;
97 
98 	error = clk_set_rate(&main_parent->base, parent_rate);
99 	if (error != 0)
100 		goto done;
101 
102 	for (int i = 0; i < __arraycount(arm->divs); i++) {
103 		if (arm->divs[i].reg == 0 && arm->divs[i].mask == 0)
104 			break;
105 
106 		const uint32_t write_mask = arm->divs[i].mask << 16;
107 		const uint32_t write_val = __SHIFTIN(arm_rate->div - 1,
108 		    arm->divs[i].mask);
109 		CRU_WRITE(sc, arm->divs[i].reg, write_mask | write_val);
110 	}
111 
112 done:
113 	rk_cru_arm_set_parent(sc, clk, arm->parents[arm->mux_main]);
114 	return error;
115 }
116 
117 static int
rk_cru_arm_set_rate_cpurates(struct rk_cru_softc * sc,struct rk_cru_clk * clk,u_int rate)118 rk_cru_arm_set_rate_cpurates(struct rk_cru_softc *sc,
119     struct rk_cru_clk *clk, u_int rate)
120 {
121 	struct rk_cru_arm *arm = &clk->u.arm;
122 	struct rk_cru_clk *main_parent, *alt_parent;
123 	const struct rk_cru_cpu_rate *cpu_rate = NULL;
124 	uint32_t write_mask, write_val;
125 	int error;
126 
127 	KASSERT(clk->type == RK_CRU_ARM);
128 
129 	if (arm->cpurates == NULL || rate == 0)
130 		return EIO;
131 
132 	for (int i = 0; i < arm->nrates; i++)
133 		if (arm->cpurates[i].rate == rate) {
134 			cpu_rate = &arm->cpurates[i];
135 			break;
136 		}
137 	if (cpu_rate == NULL)
138 		return EINVAL;
139 
140 	main_parent = rk_cru_clock_find(sc, arm->parents[arm->mux_main]);
141 	alt_parent = rk_cru_clock_find(sc, arm->parents[arm->mux_alt]);
142 	if (main_parent == NULL || alt_parent == NULL) {
143 		device_printf(sc->sc_dev, "couldn't get clock parents\n");
144 		return ENXIO;
145 	}
146 
147 	/* XXX: TODO: apply cpu_rate->pre_muxs[] */
148 
149 	error = rk_cru_arm_set_parent(sc, clk, arm->parents[arm->mux_alt]);
150 	if (error != 0)
151 		return error;
152 
153 	error = clk_set_rate(&main_parent->base, rate);
154 	if (error != 0)
155 		goto done;
156 
157 	for (int i = 0; i < __arraycount(cpu_rate->divs); i++) {
158 		if (cpu_rate->divs[i].reg == 0 && cpu_rate->divs[i].mask == 0 &&
159 		    cpu_rate->divs[i].val == 0)
160 			break;
161 
162 		write_mask = cpu_rate->divs[i].mask << 16;
163 		write_val = cpu_rate->divs[i].val;
164 		CRU_WRITE(sc, cpu_rate->divs[i].reg, write_mask | write_val);
165 	}
166 
167 	for (int i = 0; i < __arraycount(arm->divs); i++) {
168 		if (arm->divs[i].reg == 0 && arm->divs[i].mask == 0)
169 			break;
170 
171 		write_mask = arm->divs[i].mask << 16;
172 		write_val = __SHIFTIN(0, arm->divs[i].mask);
173 		CRU_WRITE(sc, arm->divs[i].reg, write_mask | write_val);
174 	}
175 
176 	/* XXX: TODO: apply cpu_rate->post_muxs[] */
177 
178 done:
179 	rk_cru_arm_set_parent(sc, clk, arm->parents[arm->mux_main]);
180 	return error;
181 }
182 
183 
184 int
rk_cru_arm_set_rate(struct rk_cru_softc * sc,struct rk_cru_clk * clk,u_int rate)185 rk_cru_arm_set_rate(struct rk_cru_softc *sc,
186     struct rk_cru_clk *clk, u_int rate)
187 {
188 	struct rk_cru_arm *arm = &clk->u.arm;
189 
190 	if (arm->rates)
191 		return rk_cru_arm_set_rate_rates(sc, clk, rate);
192 	else if (arm->cpurates)
193 		return rk_cru_arm_set_rate_cpurates(sc, clk, rate);
194 	else
195 		return EIO;
196 }
197 
198 const char *
rk_cru_arm_get_parent(struct rk_cru_softc * sc,struct rk_cru_clk * clk)199 rk_cru_arm_get_parent(struct rk_cru_softc *sc,
200     struct rk_cru_clk *clk)
201 {
202 	struct rk_cru_arm *arm = &clk->u.arm;
203 
204 	KASSERT(clk->type == RK_CRU_ARM);
205 
206 	const uint32_t val = CRU_READ(sc, arm->mux_reg);
207 	const u_int mux = __SHIFTOUT(val, arm->mux_mask);
208 
209 	return arm->parents[mux];
210 }
211 
212 int
rk_cru_arm_set_parent(struct rk_cru_softc * sc,struct rk_cru_clk * clk,const char * parent)213 rk_cru_arm_set_parent(struct rk_cru_softc *sc,
214     struct rk_cru_clk *clk, const char *parent)
215 {
216 	struct rk_cru_arm *arm = &clk->u.arm;
217 
218 	KASSERT(clk->type == RK_CRU_ARM);
219 
220 	for (u_int mux = 0; mux < arm->nparents; mux++)
221 		if (strcmp(arm->parents[mux], parent) == 0) {
222 			const uint32_t write_mask = arm->mux_mask << 16;
223 			const uint32_t write_val = __SHIFTIN(mux, arm->mux_mask);
224 
225 			CRU_WRITE(sc, arm->mux_reg, write_mask | write_val);
226 			return 0;
227 		}
228 
229 	return EINVAL;
230 }
231