xref: /netbsd-src/sys/arch/arm/rockchip/rk_cru_mux.c (revision a515ac423f83e7933b61c8c4cdc5c2374b4a637d)
1 /* $NetBSD: rk_cru_mux.c,v 1.2 2018/06/30 17:54:07 jmcneill 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_mux.c,v 1.2 2018/06/30 17:54:07 jmcneill 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 const char *
rk_cru_mux_get_parent(struct rk_cru_softc * sc,struct rk_cru_clk * clk)40 rk_cru_mux_get_parent(struct rk_cru_softc *sc,
41     struct rk_cru_clk *clk)
42 {
43 	struct rk_cru_mux *mux = &clk->u.mux;
44 	const bool mux_grf = (mux->flags & RK_MUX_GRF) != 0;
45 	uint32_t val;
46 
47 	KASSERT(clk->type == RK_CRU_MUX);
48 
49 	if (mux_grf) {
50 		if (!HAS_GRF(sc))
51 			return NULL;
52 		syscon_lock(sc->sc_grf);
53 		val = syscon_read_4(sc->sc_grf, mux->reg);
54 		syscon_unlock(sc->sc_grf);
55 	} else {
56 		val = CRU_READ(sc, mux->reg);
57 	}
58 	const u_int index = __SHIFTOUT(val, mux->mask);
59 
60 	return mux->parents[index];
61 }
62 
63 int
rk_cru_mux_set_parent(struct rk_cru_softc * sc,struct rk_cru_clk * clk,const char * parent)64 rk_cru_mux_set_parent(struct rk_cru_softc *sc,
65     struct rk_cru_clk *clk, const char *parent)
66 {
67 	struct rk_cru_mux *mux = &clk->u.mux;
68 	const bool mux_grf = (mux->flags & RK_MUX_GRF) != 0;
69 
70 	KASSERT(clk->type == RK_CRU_MUX);
71 
72 	if (mux_grf && !HAS_GRF(sc))
73 		return ENXIO;
74 
75 	for (u_int index = 0; index < mux->nparents; index++) {
76 		if (strcmp(mux->parents[index], parent) == 0) {
77 			const uint32_t write_mask = mux->mask << 16;
78 			const uint32_t write_val = __SHIFTIN(index, mux->mask);
79 
80 			if (mux_grf) {
81 				syscon_lock(sc->sc_grf);
82 				syscon_write_4(sc->sc_grf, mux->reg, write_mask | write_val);
83 				syscon_unlock(sc->sc_grf);
84 			} else
85 				CRU_WRITE(sc, mux->reg, write_mask | write_val);
86 
87 			return 0;
88 		}
89 	}
90 
91 	return EINVAL;
92 }
93