1 /* $NetBSD: imx_ccm_mux.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_mux.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 #include <dev/fdt/fdtvar.h>
40
41 const char *
imx_ccm_mux_get_parent(struct imx_ccm_softc * sc,struct imx_ccm_clk * clk)42 imx_ccm_mux_get_parent(struct imx_ccm_softc *sc,
43 struct imx_ccm_clk *clk)
44 {
45 struct imx_ccm_mux *mux = &clk->u.mux;
46
47 KASSERT(clk->type == IMX_CCM_MUX);
48
49 const uint32_t val = CCM_READ(sc, clk->regidx, mux->reg);
50 const u_int sel = __SHIFTOUT(val, mux->sel);
51
52 if (sel >= mux->nparents)
53 return NULL;
54
55 return mux->parents[sel];
56 }
57
58 int
imx_ccm_mux_set_parent(struct imx_ccm_softc * sc,struct imx_ccm_clk * clk,const char * parent)59 imx_ccm_mux_set_parent(struct imx_ccm_softc *sc,
60 struct imx_ccm_clk *clk, const char *parent)
61 {
62 struct imx_ccm_mux *mux = &clk->u.mux;
63 uint32_t val;
64
65 KASSERT(clk->type == IMX_CCM_MUX);
66
67 for (u_int sel = 0; sel < mux->nparents; sel++) {
68 if (strcmp(mux->parents[sel], parent) == 0) {
69 val = CCM_READ(sc, clk->regidx, mux->reg);
70 val &= ~mux->sel;
71 val |= __SHIFTIN(sel, mux->sel);
72 CCM_WRITE(sc, clk->regidx, mux->reg, val);
73 return 0;
74 }
75 }
76
77 return EINVAL;
78 }
79