1 /*-
2  * Copyright (c) 2016 Michal Meloun <mmel@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/param.h>
28 #include <sys/systm.h>
29 #include <sys/bus.h>
30 #include <sys/lock.h>
31 #include <sys/mutex.h>
32 #include <sys/rman.h>
33 
34 #include <machine/bus.h>
35 
36 #include <dev/clk/clk.h>
37 
38 #include <dt-bindings/clock/tegra124-car.h>
39 #include "tegra124_car.h"
40 
41 /* Flags */
42 #define	SMF_HAVE_DIVIDER_2	1
43 
44 struct super_mux_def {
45 	struct clknode_init_def	clkdef;
46 	uint32_t		base_reg;
47 	uint32_t		flags;
48 	int			src_pllx;
49 	int			src_div2;
50 };
51 
52 #define	PLIST(x) static const char *x[]
53 #define	SM(_id, cn, pl, r, x, d, f)				\
54 {									\
55 	.clkdef.id = _id,						\
56 	.clkdef.name = cn,						\
57 	.clkdef.parent_names = pl,					\
58 	.clkdef.parent_cnt = nitems(pl),				\
59 	.clkdef.flags = CLK_NODE_STATIC_STRINGS,				\
60 	.base_reg = r,							\
61 	.src_pllx = x,							\
62 	.src_div2 = d,							\
63 	.flags = f,							\
64 }
65 
66 PLIST(cclk_g_parents) = {
67 	"clk_m", "pllC_out0", "clk_s", "pllM_out0",
68 	"pllP_out0", "pllP_out4", "pllC2_out0", "pllC3_out0",
69 	"pllX_out", NULL, NULL, NULL,
70 	NULL, NULL, NULL,NULL, // "dfllCPU_out0"
71 };
72 
73 PLIST(cclk_lp_parents) = {
74 	"clk_m", "pllC_out0", "clk_s", "pllM_out0",
75 	"pllP_out0", "pllP_out4", "pllC2_out0", "pllC3_out0",
76 	"pllX_out", NULL, NULL, NULL,
77 	NULL, NULL, NULL, NULL,
78 	"pllX_out0"
79 };
80 
81 PLIST(sclk_parents) = {
82 	"clk_m", "pllC_out1", "pllP_out4", "pllP_out0",
83 	"pllP_out2", "pllC_out0", "clk_s", "pllM_out1",
84 };
85 
86 static struct super_mux_def super_mux_def[] = {
87  SM(TEGRA124_CLK_CCLK_G, "cclk_g", cclk_g_parents, CCLKG_BURST_POLICY, 0, 0, 0),
88  SM(TEGRA124_CLK_CCLK_LP, "cclk_lp", cclk_lp_parents, CCLKLP_BURST_POLICY, 8, 16, SMF_HAVE_DIVIDER_2),
89  SM(TEGRA124_CLK_SCLK, "sclk", sclk_parents, SCLK_BURST_POLICY, 0, 0, 0),
90 };
91 
92 static int super_mux_init(struct clknode *clk, device_t dev);
93 static int super_mux_set_mux(struct clknode *clk, int idx);
94 
95 struct super_mux_sc {
96 	device_t		clkdev;
97 	uint32_t		base_reg;
98 	int			src_pllx;
99 	int			src_div2;
100 	uint32_t		flags;
101 
102 	int 			mux;
103 };
104 
105 static clknode_method_t super_mux_methods[] = {
106 	/* Device interface */
107 	CLKNODEMETHOD(clknode_init,		super_mux_init),
108 	CLKNODEMETHOD(clknode_set_mux, 		super_mux_set_mux),
109 	CLKNODEMETHOD_END
110 };
111 DEFINE_CLASS_1(tegra124_super_mux, tegra124_super_mux_class, super_mux_methods,
112    sizeof(struct super_mux_sc), clknode_class);
113 
114 /* Mux status. */
115 #define	SUPER_MUX_STATE_STDBY		0
116 #define	SUPER_MUX_STATE_IDLE		1
117 #define	SUPER_MUX_STATE_RUN		2
118 #define	SUPER_MUX_STATE_IRQ		3
119 #define	SUPER_MUX_STATE_FIQ		4
120 
121 /* Mux register bits. */
122 #define	SUPER_MUX_STATE_BIT_SHIFT	28
123 #define	SUPER_MUX_STATE_BIT_MASK	0xF
124 /* State is Priority encoded */
125 #define	SUPER_MUX_STATE_BIT_STDBY	0x00
126 #define	SUPER_MUX_STATE_BIT_IDLE	0x01
127 #define	SUPER_MUX_STATE_BIT_RUN		0x02
128 #define	SUPER_MUX_STATE_BIT_IRQ		0x04
129 #define	SUPER_MUX_STATE_BIT_FIQ		0x08
130 
131 #define	SUPER_MUX_MUX_WIDTH		4
132 #define	SUPER_MUX_LP_DIV2_BYPASS	(1 << 16)
133 
134 static uint32_t
135 super_mux_get_state(uint32_t reg)
136 {
137 	reg = (reg >> SUPER_MUX_STATE_BIT_SHIFT) & SUPER_MUX_STATE_BIT_MASK;
138 	if (reg & SUPER_MUX_STATE_BIT_FIQ)
139 		 return (SUPER_MUX_STATE_FIQ);
140 	if (reg & SUPER_MUX_STATE_BIT_IRQ)
141 		 return (SUPER_MUX_STATE_IRQ);
142 	if (reg & SUPER_MUX_STATE_BIT_RUN)
143 		 return (SUPER_MUX_STATE_RUN);
144 	if (reg & SUPER_MUX_STATE_BIT_IDLE)
145 		 return (SUPER_MUX_STATE_IDLE);
146 	return (SUPER_MUX_STATE_STDBY);
147 }
148 
149 static int
150 super_mux_init(struct clknode *clk, device_t dev)
151 {
152 	struct super_mux_sc *sc;
153 	uint32_t reg;
154 	int shift, state;
155 
156 	sc = clknode_get_softc(clk);
157 
158 	DEVICE_LOCK(sc);
159 	RD4(sc, sc->base_reg, &reg);
160 	DEVICE_UNLOCK(sc);
161 	state = super_mux_get_state(reg);
162 
163 	if ((state != SUPER_MUX_STATE_RUN) &&
164 	    (state != SUPER_MUX_STATE_IDLE)) {
165 		panic("Unexpected super mux state: %u", state);
166 	}
167 
168 	shift = state * SUPER_MUX_MUX_WIDTH;
169 
170 	sc->mux = (reg >> shift) & ((1 << SUPER_MUX_MUX_WIDTH) - 1);
171 
172 	/*
173 	 * CCLKLP uses PLLX/2 as source if LP_DIV2_BYPASS isn't set
174 	 * and source mux is set to PLLX.
175 	 */
176 	if (sc->flags & SMF_HAVE_DIVIDER_2) {
177 		if (((reg & SUPER_MUX_LP_DIV2_BYPASS) == 0) &&
178 		    (sc->mux == sc->src_pllx))
179 		sc->mux = sc->src_div2;
180 	}
181 	clknode_init_parent_idx(clk, sc->mux);
182 
183 	return(0);
184 }
185 
186 static int
187 super_mux_set_mux(struct clknode *clk, int idx)
188 {
189 
190 	struct super_mux_sc *sc;
191 	int shift, state;
192 	uint32_t reg, dummy;
193 
194 	sc = clknode_get_softc(clk);
195 
196 	DEVICE_LOCK(sc);
197 	RD4(sc, sc->base_reg, &reg);
198 	state = super_mux_get_state(reg);
199 
200 	if ((state != SUPER_MUX_STATE_RUN) &&
201 	    (state != SUPER_MUX_STATE_IDLE)) {
202 		panic("Unexpected super mux state: %u", state);
203 	}
204 	shift = (state - 1) * SUPER_MUX_MUX_WIDTH;
205 	sc->mux = idx;
206 	if (sc->flags & SMF_HAVE_DIVIDER_2) {
207 		if (idx == sc->src_div2) {
208 			idx = sc->src_pllx;
209 			reg &= ~SUPER_MUX_LP_DIV2_BYPASS;
210 			WR4(sc, sc->base_reg, reg);
211 			RD4(sc, sc->base_reg, &dummy);
212 		} else if (idx == sc->src_pllx) {
213 			reg = SUPER_MUX_LP_DIV2_BYPASS;
214 			WR4(sc, sc->base_reg, reg);
215 			RD4(sc, sc->base_reg, &dummy);
216 		}
217 	}
218 	reg &= ~(((1 << SUPER_MUX_MUX_WIDTH) - 1) << shift);
219 	reg |= idx << shift;
220 
221 	WR4(sc, sc->base_reg, reg);
222 	RD4(sc, sc->base_reg, &dummy);
223 	DEVICE_UNLOCK(sc);
224 
225 	return(0);
226 }
227 
228 static int
229 super_mux_register(struct clkdom *clkdom, struct super_mux_def *clkdef)
230 {
231 	struct clknode *clk;
232 	struct super_mux_sc *sc;
233 
234 	clk = clknode_create(clkdom, &tegra124_super_mux_class,
235 	    &clkdef->clkdef);
236 	if (clk == NULL)
237 		return (1);
238 
239 	sc = clknode_get_softc(clk);
240 	sc->clkdev = clknode_get_device(clk);
241 	sc->base_reg = clkdef->base_reg;
242 	sc->src_pllx = clkdef->src_pllx;
243 	sc->src_div2 = clkdef->src_div2;
244 	sc->flags = clkdef->flags;
245 
246 	clknode_register(clkdom, clk);
247 	return (0);
248 }
249 
250 void
251 tegra124_super_mux_clock(struct tegra124_car_softc *sc)
252 {
253 	int i, rv;
254 
255 	for (i = 0; i <  nitems(super_mux_def); i++) {
256 		rv = super_mux_register(sc->clkdom, &super_mux_def[i]);
257 		if (rv != 0)
258 			panic("super_mux_register failed");
259 	}
260 
261 }
262