1/* $NetBSD: fdt_powerdomain.c,v 1.2 2024/06/12 06:39:28 rin Exp $ */ 2 3/*- 4 * Copyright (c) 2022 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Nick Hudson 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32#include <sys/cdefs.h> 33__KERNEL_RCSID(0, "$NetBSD: fdt_powerdomain.c,v 1.2 2024/06/12 06:39:28 rin Exp $"); 34 35#include <sys/param.h> 36 37#include <sys/bus.h> 38#include <sys/kmem.h> 39#include <sys/queue.h> 40 41#include <libfdt.h> 42#include <dev/fdt/fdtvar.h> 43 44 45struct fdtbus_powerdomain_controller { 46 device_t pdc_dev; 47 int pdc_phandle; 48 49 void *pdc_cookie; 50 51 int pdc_cells; 52 53 const struct fdtbus_powerdomain_controller_func *pdc_funcs; 54 55 LIST_ENTRY(fdtbus_powerdomain_controller) pdc_next; 56}; 57 58static LIST_HEAD(, fdtbus_powerdomain_controller) fdtbus_powerdomain_controllers = 59 LIST_HEAD_INITIALIZER(fdtbus_powerdomain_controllers); 60 61int 62fdtbus_register_powerdomain_controller(device_t dev, int phandle, 63 const struct fdtbus_powerdomain_controller_func *funcs) 64{ 65 struct fdtbus_powerdomain_controller *pdc; 66 67 uint32_t cells; 68 if (of_getprop_uint32(phandle, "#power-domain-cells", &cells) != 0) { 69 aprint_debug_dev(dev, "missing #power-domain-cells"); 70 return EINVAL; 71 } 72 73 pdc = kmem_alloc(sizeof(*pdc), KM_SLEEP); 74 pdc->pdc_dev = dev; 75 pdc->pdc_phandle = phandle; 76 pdc->pdc_funcs = funcs; 77 pdc->pdc_cells = cells; 78 79 LIST_INSERT_HEAD(&fdtbus_powerdomain_controllers, pdc, pdc_next); 80 81 return 0; 82} 83 84static struct fdtbus_powerdomain_controller * 85fdtbus_powerdomain_lookup(int phandle) 86{ 87 struct fdtbus_powerdomain_controller *pdc; 88 89 LIST_FOREACH(pdc, &fdtbus_powerdomain_controllers, pdc_next) { 90 if (pdc->pdc_phandle == phandle) 91 return pdc; 92 } 93 94 return NULL; 95} 96 97static int 98fdtbus_powerdomain_enable_internal(int phandle, int index, bool enable) 99{ 100 int len; 101 const uint32_t *pds = fdtbus_get_prop(phandle, "power-domains", &len); 102 103 if (pds == NULL) 104 return EINVAL; 105 106 for (const uint32_t *pd = pds; pd < pds + len / sizeof(*pd); index--) { 107 uint32_t pd_node = 108 fdtbus_get_phandle_from_native(be32toh(pd[0])); 109 struct fdtbus_powerdomain_controller *pdc = 110 fdtbus_powerdomain_lookup(pd_node); 111 112 if (pdc == NULL) 113 return ENXIO; 114 115 if (index < 0 || index == 0) 116 pdc->pdc_funcs->pdc_enable(pdc->pdc_dev, pd, enable); 117 if (index == 0) 118 break; 119 120 pd += pdc->pdc_cells + 1; 121 } 122 123 return 0; 124} 125 126int 127fdtbus_powerdomain_enable_index(int phandle, int index) 128{ 129 return fdtbus_powerdomain_enable_internal(phandle, index, true); 130} 131 132int 133fdtbus_powerdomain_disable_index(int phandle, int index) 134{ 135 return fdtbus_powerdomain_enable_internal(phandle, index, false); 136} 137 138int 139fdtbus_powerdomain_enable(int node) 140{ 141 return fdtbus_powerdomain_enable_index(node, -1); 142} 143 144int 145fdtbus_powerdomain_disable(int node) 146{ 147 return fdtbus_powerdomain_disable_index(node, -1); 148} 149