1 /* $NetBSD: imx_ccm_fixed_factor.c,v 1.1 2020/12/23 14:42:38 skrll Exp $ */
2
3 /*-
4 * Copyright (c) 2020 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: imx_ccm_fixed_factor.c,v 1.1 2020/12/23 14:42:38 skrll Exp $");
31
32 #include <sys/param.h>
33 #include <sys/bus.h>
34
35 #include <dev/clk/clk_backend.h>
36
37 #include <arm/nxp/imx_ccm.h>
38
39 static u_int
imx_ccm_fixed_factor_get_parent_rate(struct clk * clkp)40 imx_ccm_fixed_factor_get_parent_rate(struct clk *clkp)
41 {
42 struct clk *clkp_parent;
43
44 clkp_parent = clk_get_parent(clkp);
45 if (clkp_parent == NULL)
46 return 0;
47
48 return clk_get_rate(clkp_parent);
49 }
50
51 u_int
imx_ccm_fixed_factor_get_rate(struct imx_ccm_softc * sc,struct imx_ccm_clk * clk)52 imx_ccm_fixed_factor_get_rate(struct imx_ccm_softc *sc,
53 struct imx_ccm_clk *clk)
54 {
55 struct imx_ccm_fixed_factor *fixed_factor = &clk->u.fixed_factor;
56 struct clk *clkp = &clk->base;
57
58 KASSERT(clk->type == IMX_CCM_FIXED_FACTOR);
59
60 const u_int p_rate = imx_ccm_fixed_factor_get_parent_rate(clkp);
61 if (p_rate == 0)
62 return 0;
63
64 return (u_int)(((uint64_t)p_rate * fixed_factor->mult) / fixed_factor->div);
65 }
66
67 static int
imx_ccm_fixed_factor_set_parent_rate(struct clk * clkp,u_int rate)68 imx_ccm_fixed_factor_set_parent_rate(struct clk *clkp, u_int rate)
69 {
70 struct clk *clkp_parent;
71
72 clkp_parent = clk_get_parent(clkp);
73 if (clkp_parent == NULL)
74 return ENXIO;
75
76 return clk_set_rate(clkp_parent, rate);
77 }
78
79 int
imx_ccm_fixed_factor_set_rate(struct imx_ccm_softc * sc,struct imx_ccm_clk * clk,u_int rate)80 imx_ccm_fixed_factor_set_rate(struct imx_ccm_softc *sc,
81 struct imx_ccm_clk *clk, u_int rate)
82 {
83 struct imx_ccm_fixed_factor *fixed_factor = &clk->u.fixed_factor;
84 struct clk *clkp = &clk->base;
85
86 KASSERT(clk->type == IMX_CCM_FIXED_FACTOR);
87
88 rate *= fixed_factor->div;
89 rate /= fixed_factor->mult;
90
91 return imx_ccm_fixed_factor_set_parent_rate(clkp, rate);
92 }
93
94 const char *
imx_ccm_fixed_factor_get_parent(struct imx_ccm_softc * sc,struct imx_ccm_clk * clk)95 imx_ccm_fixed_factor_get_parent(struct imx_ccm_softc *sc,
96 struct imx_ccm_clk *clk)
97 {
98 struct imx_ccm_fixed_factor *fixed_factor = &clk->u.fixed_factor;
99
100 KASSERT(clk->type == IMX_CCM_FIXED_FACTOR);
101
102 return fixed_factor->parent;
103 }
104