1 /* $NetBSD: meson_resets.c,v 1.4 2021/01/27 03:10:18 thorpej Exp $ */ 2 3 /*- 4 * Copyright (c) 2017-2019 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: meson_resets.c,v 1.4 2021/01/27 03:10:18 thorpej Exp $"); 31 32 #include <sys/param.h> 33 #include <sys/bus.h> 34 #include <sys/cpu.h> 35 #include <sys/device.h> 36 37 #include <dev/fdt/fdtvar.h> 38 39 #include <dev/clk/clk_backend.h> 40 41 #define RESET_REG(index) (((index) / 32) * 4) 42 #define RESET_MASK(index) __BIT((index) % 32) 43 44 #define LEVEL_OFFSET 0x7c 45 46 static const struct device_compatible_entry compat_data[] = { 47 { .compat = "amlogic,meson8b-reset" }, 48 { .compat = "amlogic,meson-axg-reset" }, 49 { .compat = "amlogic,meson-gxbb-reset" }, 50 DEVICE_COMPAT_EOL 51 }; 52 53 struct meson_resets_softc { 54 device_t sc_dev; 55 bus_space_tag_t sc_bst; 56 bus_space_handle_t sc_bsh; 57 }; 58 59 #define RESET_READ(sc, reg) \ 60 bus_space_read_4((sc)->sc_bst, (sc)->sc_bsh, (reg)) 61 #define RESET_WRITE(sc, reg, val) \ 62 bus_space_write_4((sc)->sc_bst, (sc)->sc_bsh, (reg), (val)) 63 64 static void * 65 meson_resets_acquire(device_t dev, const void *data, size_t len) 66 { 67 if (len != 4) 68 return NULL; 69 70 /* Specifier is an index. Just return it. */ 71 return (void *)(uintptr_t)be32dec(data); 72 } 73 74 static void 75 meson_resets_release(device_t dev, void *priv) 76 { 77 } 78 79 static int 80 meson_resets_assert(device_t dev, void *priv) 81 { 82 struct meson_resets_softc * const sc = device_private(dev); 83 const uintptr_t index = (uintptr_t)priv; 84 85 const bus_size_t reset_reg = RESET_REG(index) + LEVEL_OFFSET; 86 const uint32_t reset_mask = RESET_MASK(index); 87 88 const uint32_t val = RESET_READ(sc, reset_reg); 89 RESET_WRITE(sc, reset_reg, val & ~reset_mask); 90 91 return 0; 92 } 93 94 static int 95 meson_resets_deassert(device_t dev, void *priv) 96 { 97 struct meson_resets_softc * const sc = device_private(dev); 98 const uintptr_t index = (uintptr_t)priv; 99 100 const bus_size_t reset_reg = RESET_REG(index) + LEVEL_OFFSET; 101 const uint32_t reset_mask = RESET_MASK(index); 102 103 const uint32_t val = RESET_READ(sc, reset_reg); 104 RESET_WRITE(sc, reset_reg, val | reset_mask); 105 106 return 0; 107 } 108 109 static const struct fdtbus_reset_controller_func meson_fdtreset_funcs = { 110 .acquire = meson_resets_acquire, 111 .release = meson_resets_release, 112 .reset_assert = meson_resets_assert, 113 .reset_deassert = meson_resets_deassert, 114 }; 115 116 static int 117 meson_resets_match(device_t parent, cfdata_t cf, void *aux) 118 { 119 struct fdt_attach_args * const faa = aux; 120 121 return of_compatible_match(faa->faa_phandle, compat_data); 122 } 123 124 static void 125 meson_resets_attach(device_t parent, device_t self, void *aux) 126 { 127 struct meson_resets_softc * const sc = device_private(self); 128 struct fdt_attach_args * const faa = aux; 129 const int phandle = faa->faa_phandle; 130 bus_addr_t addr; 131 bus_size_t size; 132 133 if (fdtbus_get_reg(phandle, 0, &addr, &size) != 0) { 134 aprint_error(": couldn't get registers\n"); 135 return; 136 } 137 138 sc->sc_dev = self; 139 sc->sc_bst = faa->faa_bst; 140 if (bus_space_map(sc->sc_bst, addr, size, 0, &sc->sc_bsh) != 0) { 141 aprint_error(": couldn't map registers\n"); 142 return; 143 } 144 145 aprint_naive("\n"); 146 aprint_normal("\n"); 147 148 fdtbus_register_reset_controller(sc->sc_dev, phandle, 149 &meson_fdtreset_funcs); 150 } 151 152 CFATTACH_DECL_NEW(meson_resets, sizeof(struct meson_resets_softc), 153 meson_resets_match, meson_resets_attach, NULL, NULL); 154