1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2022 Ruslan Bukin <br@bsdpad.com> 5 * 6 * This work was supported by Innovate UK project 105694, "Digital Security 7 * by Design (DSbD) Technology Platform Prototype". 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 */ 30 31 #include <sys/param.h> 32 #include <sys/systm.h> 33 #include <sys/bus.h> 34 #include <sys/rman.h> 35 #include <sys/kernel.h> 36 #include <sys/module.h> 37 38 #include <machine/bus.h> 39 40 #include <dev/fdt/simplebus.h> 41 #include <dev/fdt/fdt_common.h> 42 #include <dev/ofw/ofw_bus_subr.h> 43 44 #include "mmio_sram_if.h" 45 46 #define dprintf(fmt, ...) 47 48 static struct resource_spec mmio_sram_spec[] = { 49 { SYS_RES_MEMORY, 0, RF_ACTIVE }, 50 { -1, 0 } 51 }; 52 53 struct mmio_sram_softc { 54 struct resource *res[1]; 55 device_t dev; 56 }; 57 58 static int 59 mmio_sram_probe(device_t dev) 60 { 61 62 if (!ofw_bus_is_compatible(dev, "mmio-sram")) 63 return (ENXIO); 64 65 if (!ofw_bus_status_okay(dev)) 66 return (ENXIO); 67 68 device_set_desc(dev, "MMIO SRAM"); 69 70 return (BUS_PROBE_DEFAULT); 71 } 72 73 static int 74 mmio_sram_attach(device_t dev) 75 { 76 struct mmio_sram_softc *sc; 77 phandle_t node; 78 int rv; 79 80 sc = device_get_softc(dev); 81 sc->dev = dev; 82 83 if (bus_alloc_resources(dev, mmio_sram_spec, sc->res) != 0) { 84 device_printf(dev, "Can't allocate resources for device.\n"); 85 return (ENXIO); 86 } 87 88 node = ofw_bus_get_node(dev); 89 if (node == -1) 90 return (ENXIO); 91 92 rv = simplebus_attach_impl(dev, SB_FLAG_NO_RANGES, node); 93 if (rv != 0) 94 return (rv); 95 96 bus_attach_children(dev); 97 return (0); 98 } 99 100 static int 101 mmio_sram_detach(device_t dev) 102 { 103 struct mmio_sram_softc *sc; 104 105 sc = device_get_softc(dev); 106 107 bus_release_resources(dev, mmio_sram_spec, sc->res); 108 109 return (0); 110 } 111 112 static uint8_t 113 mmio_sram_read_1(device_t dev, bus_size_t offset) 114 { 115 struct mmio_sram_softc *sc; 116 117 sc = device_get_softc(dev); 118 119 dprintf("%s: reading from %lx\n", __func__, offset); 120 121 return (bus_read_1(sc->res[0], offset)); 122 } 123 124 static void 125 mmio_sram_write_1(device_t dev, bus_size_t offset, uint8_t val) 126 { 127 struct mmio_sram_softc *sc; 128 129 sc = device_get_softc(dev); 130 131 dprintf("%s: writing to %lx val %x\n", __func__, offset, val); 132 133 bus_write_1(sc->res[0], offset, val); 134 } 135 136 static device_method_t mmio_sram_methods[] = { 137 /* Device Interface */ 138 DEVMETHOD(device_probe, mmio_sram_probe), 139 DEVMETHOD(device_attach, mmio_sram_attach), 140 DEVMETHOD(device_detach, mmio_sram_detach), 141 142 /* MMIO interface */ 143 DEVMETHOD(mmio_sram_read_1, mmio_sram_read_1), 144 DEVMETHOD(mmio_sram_write_1, mmio_sram_write_1), 145 DEVMETHOD_END 146 }; 147 148 DEFINE_CLASS_1(mmio_sram, mmio_sram_driver, mmio_sram_methods, 149 sizeof(struct mmio_sram_softc), simplebus_driver); 150 151 EARLY_DRIVER_MODULE(mmio_sram, simplebus, mmio_sram_driver, 0, 0, 152 BUS_PASS_SUPPORTDEV + BUS_PASS_ORDER_MIDDLE); 153 MODULE_VERSION(mmio_sram, 1); 154