sys/arm/ti/clk/ti_divider_clock.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (c) 2020 Oskar Holmlund <oskar.holmlund@ohdata.se>
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
  20  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  21  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  22  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  23  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  25  * SUCH DAMAGE.
  26  *
  27  * $FreeBSD$
  28  */
  29
  30 #include <sys/cdefs.h>
  31 __FBSDID("$FreeBSD$");
  32
  33 #include <sys/param.h>
  34 #include <sys/conf.h>
  35 #include <sys/bus.h>
  36 #include <sys/kernel.h>
  37 #include <sys/module.h>
  38 #include <sys/systm.h>
  39 #include <sys/libkern.h>
  40
  41 #include <machine/bus.h>
  42 #include <dev/fdt/simplebus.h>
  43
  44 #include <dev/extres/clk/clk_div.h>
  45 #include <dev/ofw/ofw_bus.h>
  46 #include <dev/ofw/ofw_bus_subr.h>
  47
  48 #include "clock_common.h"
  49
  50 #if 0
  51 #define DPRINTF(dev, msg...) device_printf(dev, msg)
  52 #else
  53 #define DPRINTF(dev, msg...)
  54 #endif
  55
  56 /*
  57  * Devicetree description
  58  * Documentation/devicetree/bindings/clock/ti/divider.txt
  59  */
  60
  61 struct ti_divider_softc {
  62         device_t                sc_dev;
  63         bool                    attach_done;
  64         struct clk_div_def      div_def;
  65
  66         struct clock_cell_info  clock_cell;
  67         struct clkdom           *clkdom;
  68 };
  69
  70 static int ti_divider_probe(device_t dev);
  71 static int ti_divider_attach(device_t dev);
  72 static int ti_divider_detach(device_t dev);
  73
  74 #define TI_DIVIDER_CLOCK                2
  75 #define TI_COMPOSITE_DIVIDER_CLOCK      1
  76 #define TI_DIVIDER_END                  0
  77
  78 static struct ofw_compat_data compat_data[] = {
  79         { "ti,divider-clock",           TI_DIVIDER_CLOCK },
  80         { "ti,composite-divider-clock", TI_COMPOSITE_DIVIDER_CLOCK },
  81         { NULL,                         TI_DIVIDER_END }
  82 };
  83
  84 static int
  85 register_clk(struct ti_divider_softc *sc) {
  86         int err;
  87
  88         sc->clkdom = clkdom_create(sc->sc_dev);
  89         if (sc->clkdom == NULL) {
  90                 DPRINTF(sc->sc_dev, "Failed to create clkdom\n");
  91                 return (ENXIO);
  92         }
  93
  94         err = clknode_div_register(sc->clkdom, &sc->div_def);
  95         if (err) {
  96                 DPRINTF(sc->sc_dev, "clknode_div_register failed %x\n", err);
  97                 return (ENXIO);
  98         }
  99
 100         err = clkdom_finit(sc->clkdom);
 101         if (err) {
 102                 DPRINTF(sc->sc_dev, "Clk domain finit fails %x.\n", err);
 103                 return (ENXIO);
 104         }
 105
 106         return (0);
 107 }
 108
 109 static int
 110 ti_divider_probe(device_t dev)
 111 {
 112         if (!ofw_bus_status_okay(dev))
 113                 return (ENXIO);
 114
 115         if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
 116                 return (ENXIO);
 117
 118         device_set_desc(dev, "TI Divider Clock");
 119
 120         return (BUS_PROBE_DEFAULT);
 121 }
 122
 123 static int
 124 ti_divider_attach(device_t dev)
 125 {
 126         struct ti_divider_softc *sc;
 127         phandle_t       node;
 128         int             err;
 129         cell_t          value;
 130         uint32_t        ti_max_div;
 131
 132         sc = device_get_softc(dev);
 133         sc->sc_dev = dev;
 134         node = ofw_bus_get_node(dev);
 135
 136         /* Grab the content of reg properties */
 137         OF_getencprop(node, "reg", &value, sizeof(value));
 138         sc->div_def.offset = value;
 139
 140         if (OF_hasprop(node, "ti,bit-shift")) {
 141                 OF_getencprop(node, "ti,bit-shift", &value, sizeof(value));
 142                 sc->div_def.i_shift = value;
 143         }
 144
 145         if (OF_hasprop(node, "ti,index-starts-at-one")) {
 146                 sc->div_def.div_flags = CLK_DIV_ZERO_BASED;
 147         }
 148
 149         if (OF_hasprop(node, "ti,index-power-of-two")) {
 150                 /* FIXME: later */
 151                 device_printf(sc->sc_dev, "ti,index-power-of-two - Not implemented\n");
 152                 /* remember to update i_width a few lines below */
 153         }
 154         if (OF_hasprop(node, "ti,max-div")) {
 155                 OF_getencprop(node, "ti,max-div", &value, sizeof(value));
 156                 ti_max_div = value;
 157         }
 158
 159         if (OF_hasprop(node, "clock-output-names"))
 160                 device_printf(sc->sc_dev, "clock-output-names\n");
 161         if (OF_hasprop(node, "ti,dividers"))
 162                 device_printf(sc->sc_dev, "ti,dividers\n");
 163         if (OF_hasprop(node, "ti,min-div"))
 164                 device_printf(sc->sc_dev, "ti,min-div - Not implemented\n");
 165
 166         if (OF_hasprop(node, "ti,autoidle-shift"))
 167                 device_printf(sc->sc_dev, "ti,autoidle-shift - Not implemented\n");
 168         if (OF_hasprop(node, "ti,set-rate-parent"))
 169                 device_printf(sc->sc_dev, "ti,set-rate-parent - Not implemented\n");
 170         if (OF_hasprop(node, "ti,latch-bit"))
 171                 device_printf(sc->sc_dev, "ti,latch-bit - Not implemented\n");
 172
 173         /* Figure out the width from ti_max_div */
 174         if (sc->div_def.div_flags)
 175                 sc->div_def.i_width = fls(ti_max_div-1);
 176         else
 177                 sc->div_def.i_width = fls(ti_max_div);
 178
 179         DPRINTF(sc->sc_dev, "div_def.i_width %x\n", sc->div_def.i_width);
 180
 181         read_clock_cells(sc->sc_dev, &sc->clock_cell);
 182
 183         create_clkdef(sc->sc_dev, &sc->clock_cell, &sc->div_def.clkdef);
 184
 185         err = find_parent_clock_names(sc->sc_dev, &sc->clock_cell, &sc->div_def.clkdef);
 186
 187         if (err) {
 188                 /* free_clkdef will be called in ti_divider_new_pass */
 189                 DPRINTF(sc->sc_dev, "find_parent_clock_names failed\n");
 190                 return (bus_generic_attach(sc->sc_dev));
 191         }
 192
 193         err = register_clk(sc);
 194
 195         if (err) {
 196                 /* free_clkdef will be called in ti_divider_new_pass */
 197                 DPRINTF(sc->sc_dev, "register_clk failed\n");
 198                 return (bus_generic_attach(sc->sc_dev));
 199         }
 200
 201         sc->attach_done = true;
 202
 203         free_clkdef(&sc->div_def.clkdef);
 204
 205         return (bus_generic_attach(sc->sc_dev));
 206 }
 207
 208 static int
 209 ti_divider_detach(device_t dev)
 210 {
 211         return (EBUSY);
 212 }
 213
 214 static void
 215 ti_divider_new_pass(device_t dev)
 216 {
 217         struct ti_divider_softc *sc;
 218         int err;
 219
 220         sc = device_get_softc(dev);
 221
 222         if (sc->attach_done) {
 223                 return;
 224         }
 225
 226         err = find_parent_clock_names(sc->sc_dev, &sc->clock_cell, &sc->div_def.clkdef);
 227         if (err) {
 228                 /* free_clkdef will be called in a later call to ti_divider_new_pass */
 229                 DPRINTF(sc->sc_dev, "new_pass find_parent_clock_names failed\n");
 230                 return;
 231         }
 232
 233         err = register_clk(sc);
 234         if (err) {
 235                 /* free_clkdef will be called in a later call to ti_divider_new_pass */
 236                 DPRINTF(sc->sc_dev, "new_pass register_clk failed\n");
 237                 return;
 238         }
 239
 240         sc->attach_done = true;
 241
 242         free_clkdef(&sc->div_def.clkdef);
 243 }
 244
 245 static device_method_t ti_divider_methods[] = {
 246         /* Device interface */
 247         DEVMETHOD(device_probe,         ti_divider_probe),
 248         DEVMETHOD(device_attach,        ti_divider_attach),
 249         DEVMETHOD(device_detach,        ti_divider_detach),
 250
 251         /* Bus interface */
 252         DEVMETHOD(bus_new_pass,         ti_divider_new_pass),
 253
 254         DEVMETHOD_END
 255 };
 256
 257 DEFINE_CLASS_0(ti_divider, ti_divider_driver, ti_divider_methods,
 258         sizeof(struct ti_divider_softc));
 259
 260 static devclass_t ti_divider_devclass;
 261
 262 EARLY_DRIVER_MODULE(ti_divider, simplebus, ti_divider_driver,
 263         ti_divider_devclass, 0, 0, BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
 264 MODULE_VERSION(ti_divider, 1);