1 /* $NetBSD: apple_pmgr.c,v 1.2 2022/05/10 08:10:28 skrll 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: apple_pmgr.c,v 1.2 2022/05/10 08:10:28 skrll 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 /* 45 * Power manager registers 46 */ 47 #define PMGR_PS_TARGET_MASK __BITS(3, 0) 48 #define PMGR_PS_ACTUAL_MASK __BITS(7, 4) 49 #define PMGR_PS_ACTIVE 0xf 50 #define PMGR_PS_PWRGATE 0x0 51 52 struct apple_pmgr_softc { 53 device_t sc_dev; 54 bus_space_tag_t sc_bst; 55 bus_space_handle_t sc_bsh; 56 }; 57 58 #define PMGR_READ(sc, reg) \ 59 bus_space_read_4((sc)->sc_bst, (sc)->sc_bsh, (reg)) 60 #define PMGR_WRITE(sc, reg, val) \ 61 bus_space_write_4((sc)->sc_bst, (sc)->sc_bsh, (reg), (val)) 62 63 64 static const struct device_compatible_entry compat_data[] = { 65 { .compat = "apple,pmgr" }, 66 DEVICE_COMPAT_EOL 67 }; 68 69 static void 70 apple_pmgr_enable(device_t dev, const uint32_t *data, bool enable) 71 { 72 struct apple_pmgr_softc * const sc = device_private(dev); 73 const uint32_t pstate = enable ? PMGR_PS_ACTIVE : PMGR_PS_PWRGATE; 74 const int phandle = fdtbus_get_phandle_from_native(be32dec(data)); 75 76 fdtbus_powerdomain_enable(phandle); 77 78 bus_size_t off; 79 bus_size_t size; 80 if (fdtbus_get_reg(phandle, 0, &off, &size) != 0 || size != 4) { 81 aprint_error(": invalid 'reg' property\n"); 82 return; 83 } 84 85 uint32_t val = PMGR_READ(sc, off); 86 87 val &= ~PMGR_PS_TARGET_MASK; 88 val |= __SHIFTIN(pstate, PMGR_PS_TARGET_MASK); 89 PMGR_WRITE(sc, off, val); 90 91 for (int timo = 0; timo < 100; timo++) { 92 val = PMGR_READ(sc, off); 93 if (__SHIFTOUT(val, PMGR_PS_ACTUAL_MASK) == pstate) 94 break; 95 delay(1); 96 } 97 } 98 99 100 static int 101 apple_pmgr_match(device_t parent, cfdata_t cf, void *aux) 102 { 103 struct fdt_attach_args * const faa = aux; 104 105 return of_compatible_match(faa->faa_phandle, compat_data); 106 } 107 108 109 static void 110 apple_pmgr_attach(device_t parent, device_t self, void *aux) 111 { 112 struct apple_pmgr_softc * const sc = device_private(self); 113 struct fdt_attach_args * const faa = aux; 114 const int phandle = faa->faa_phandle; 115 116 bus_addr_t pmgr_addr; 117 bus_size_t pmgr_size; 118 119 int error = fdtbus_get_reg(phandle, 0, &pmgr_addr, &pmgr_size); 120 if (error) { 121 aprint_error(": couldn't get registers\n"); 122 return; 123 } 124 125 sc->sc_dev = self; 126 sc->sc_bst = faa->faa_bst; 127 128 error = bus_space_map(faa->faa_bst, pmgr_addr, pmgr_size, 0, 129 &sc->sc_bsh); 130 if (error) { 131 aprint_error(": couldn't map registers: %d\n", error); 132 return; 133 } 134 135 aprint_naive("\n"); 136 aprint_normal(": Apple PMGR\n"); 137 138 for (int node = OF_child(phandle); node; node = OF_peer(node)) { 139 static const struct device_compatible_entry compat_ps[] = { 140 { .compat = "apple,pmgr-pwrstate" }, 141 DEVICE_COMPAT_EOL 142 }; 143 144 if (!of_compatible_match(node, compat_ps)) 145 continue; 146 147 static struct fdtbus_powerdomain_controller_func funcs = { 148 .pdc_enable = apple_pmgr_enable, 149 }; 150 151 fdtbus_register_powerdomain_controller(self, node, &funcs); 152 } 153 } 154 155 CFATTACH_DECL_NEW(apple_pmgr, sizeof(struct apple_pmgr_softc), 156 apple_pmgr_match, apple_pmgr_attach, NULL, NULL); 157