meson_clk_div.c revision 1.2.2.2
1 1.2.2.2 pgoyette /* $NetBSD: meson_clk_div.c,v 1.2.2.2 2019/01/26 21:59:59 pgoyette Exp $ */ 2 1.2.2.2 pgoyette 3 1.2.2.2 pgoyette /*- 4 1.2.2.2 pgoyette * Copyright (c) 2017-2019 Jared McNeill <jmcneill (at) invisible.ca> 5 1.2.2.2 pgoyette * All rights reserved. 6 1.2.2.2 pgoyette * 7 1.2.2.2 pgoyette * Redistribution and use in source and binary forms, with or without 8 1.2.2.2 pgoyette * modification, are permitted provided that the following conditions 9 1.2.2.2 pgoyette * are met: 10 1.2.2.2 pgoyette * 1. Redistributions of source code must retain the above copyright 11 1.2.2.2 pgoyette * notice, this list of conditions and the following disclaimer. 12 1.2.2.2 pgoyette * 2. Redistributions in binary form must reproduce the above copyright 13 1.2.2.2 pgoyette * notice, this list of conditions and the following disclaimer in the 14 1.2.2.2 pgoyette * documentation and/or other materials provided with the distribution. 15 1.2.2.2 pgoyette * 16 1.2.2.2 pgoyette * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 1.2.2.2 pgoyette * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 1.2.2.2 pgoyette * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 1.2.2.2 pgoyette * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 1.2.2.2 pgoyette * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 1.2.2.2 pgoyette * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 22 1.2.2.2 pgoyette * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 1.2.2.2 pgoyette * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 1.2.2.2 pgoyette * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 1.2.2.2 pgoyette * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 1.2.2.2 pgoyette * SUCH DAMAGE. 27 1.2.2.2 pgoyette */ 28 1.2.2.2 pgoyette 29 1.2.2.2 pgoyette #include <sys/cdefs.h> 30 1.2.2.2 pgoyette __KERNEL_RCSID(0, "$NetBSD: meson_clk_div.c,v 1.2.2.2 2019/01/26 21:59:59 pgoyette Exp $"); 31 1.2.2.2 pgoyette 32 1.2.2.2 pgoyette #include <sys/param.h> 33 1.2.2.2 pgoyette #include <sys/bus.h> 34 1.2.2.2 pgoyette 35 1.2.2.2 pgoyette #include <dev/clk/clk_backend.h> 36 1.2.2.2 pgoyette 37 1.2.2.2 pgoyette #include <arm/amlogic/meson_clk.h> 38 1.2.2.2 pgoyette 39 1.2.2.2 pgoyette u_int 40 1.2.2.2 pgoyette meson_clk_div_get_rate(struct meson_clk_softc *sc, 41 1.2.2.2 pgoyette struct meson_clk_clk *clk) 42 1.2.2.2 pgoyette { 43 1.2.2.2 pgoyette struct meson_clk_div *div = &clk->u.div; 44 1.2.2.2 pgoyette struct clk *clkp, *clkp_parent; 45 1.2.2.2 pgoyette u_int rate, ratio; 46 1.2.2.2 pgoyette uint32_t val; 47 1.2.2.2 pgoyette 48 1.2.2.2 pgoyette KASSERT(clk->type == MESON_CLK_DIV); 49 1.2.2.2 pgoyette 50 1.2.2.2 pgoyette clkp = &clk->base; 51 1.2.2.2 pgoyette clkp_parent = clk_get_parent(clkp); 52 1.2.2.2 pgoyette if (clkp_parent == NULL) 53 1.2.2.2 pgoyette return 0; 54 1.2.2.2 pgoyette 55 1.2.2.2 pgoyette rate = clk_get_rate(clkp_parent); 56 1.2.2.2 pgoyette if (rate == 0) 57 1.2.2.2 pgoyette return 0; 58 1.2.2.2 pgoyette 59 1.2.2.2 pgoyette val = CLK_READ(sc, div->reg); 60 1.2.2.2 pgoyette if (div->div) 61 1.2.2.2 pgoyette ratio = __SHIFTOUT(val, div->div); 62 1.2.2.2 pgoyette else 63 1.2.2.2 pgoyette ratio = 0; 64 1.2.2.2 pgoyette 65 1.2.2.2 pgoyette if (div->flags & MESON_CLK_DIV_POWER_OF_TWO) { 66 1.2.2.2 pgoyette return rate >> ratio; 67 1.2.2.2 pgoyette } else if (div->flags & MESON_CLK_DIV_CPU_SCALE_TABLE) { 68 1.2.2.2 pgoyette if (ratio < 1 || ratio > 8) 69 1.2.2.2 pgoyette return 0; 70 1.2.2.2 pgoyette return rate / ((ratio + 1) * 2); 71 1.2.2.2 pgoyette } else { 72 1.2.2.2 pgoyette return rate / (ratio + 1); 73 1.2.2.2 pgoyette } 74 1.2.2.2 pgoyette } 75 1.2.2.2 pgoyette 76 1.2.2.2 pgoyette int 77 1.2.2.2 pgoyette meson_clk_div_set_rate(struct meson_clk_softc *sc, 78 1.2.2.2 pgoyette struct meson_clk_clk *clk, u_int new_rate) 79 1.2.2.2 pgoyette { 80 1.2.2.2 pgoyette struct meson_clk_div *div = &clk->u.div; 81 1.2.2.2 pgoyette struct clk *clkp, *clkp_parent; 82 1.2.2.2 pgoyette int parent_rate; 83 1.2.2.2 pgoyette uint32_t val, raw_div; 84 1.2.2.2 pgoyette int ratio; 85 1.2.2.2 pgoyette 86 1.2.2.2 pgoyette KASSERT(clk->type == MESON_CLK_DIV); 87 1.2.2.2 pgoyette 88 1.2.2.2 pgoyette clkp = &clk->base; 89 1.2.2.2 pgoyette clkp_parent = clk_get_parent(clkp); 90 1.2.2.2 pgoyette if (clkp_parent == NULL) 91 1.2.2.2 pgoyette return ENXIO; 92 1.2.2.2 pgoyette 93 1.2.2.2 pgoyette if ((div->flags & MESON_CLK_DIV_SET_RATE_PARENT) != 0) 94 1.2.2.2 pgoyette return clk_set_rate(clkp_parent, new_rate); 95 1.2.2.2 pgoyette 96 1.2.2.2 pgoyette if (div->div == 0) 97 1.2.2.2 pgoyette return ENXIO; 98 1.2.2.2 pgoyette 99 1.2.2.2 pgoyette val = CLK_READ(sc, div->reg); 100 1.2.2.2 pgoyette 101 1.2.2.2 pgoyette parent_rate = clk_get_rate(clkp_parent); 102 1.2.2.2 pgoyette if (parent_rate == 0) 103 1.2.2.2 pgoyette return (new_rate == 0) ? 0 : ERANGE; 104 1.2.2.2 pgoyette 105 1.2.2.2 pgoyette ratio = howmany(parent_rate, new_rate); 106 1.2.2.2 pgoyette if ((div->flags & MESON_CLK_DIV_POWER_OF_TWO) != 0) { 107 1.2.2.2 pgoyette return EINVAL; 108 1.2.2.2 pgoyette } else if ((div->flags & MESON_CLK_DIV_CPU_SCALE_TABLE) != 0) { 109 1.2.2.2 pgoyette return EINVAL; 110 1.2.2.2 pgoyette } else { 111 1.2.2.2 pgoyette raw_div = (ratio > 0) ? ratio - 1 : 0; 112 1.2.2.2 pgoyette } 113 1.2.2.2 pgoyette if (raw_div > __SHIFTOUT_MASK(div->div)) 114 1.2.2.2 pgoyette return ERANGE; 115 1.2.2.2 pgoyette 116 1.2.2.2 pgoyette val &= ~div->div; 117 1.2.2.2 pgoyette val |= __SHIFTIN(raw_div, div->div); 118 1.2.2.2 pgoyette CLK_WRITE(sc, div->reg, val); 119 1.2.2.2 pgoyette 120 1.2.2.2 pgoyette return 0; 121 1.2.2.2 pgoyette } 122 1.2.2.2 pgoyette 123 1.2.2.2 pgoyette const char * 124 1.2.2.2 pgoyette meson_clk_div_get_parent(struct meson_clk_softc *sc, 125 1.2.2.2 pgoyette struct meson_clk_clk *clk) 126 1.2.2.2 pgoyette { 127 1.2.2.2 pgoyette struct meson_clk_div *div = &clk->u.div; 128 1.2.2.2 pgoyette 129 1.2.2.2 pgoyette KASSERT(clk->type == MESON_CLK_DIV); 130 1.2.2.2 pgoyette 131 1.2.2.2 pgoyette return div->parent; 132 1.2.2.2 pgoyette } 133
Indexes created Tue Sep 30 20:09:53 GMT 2025