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 * 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 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