1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2018 Ruslan Bukin <br@bsdpad.com> 5 * All rights reserved. 6 * 7 * This software was developed by SRI International and the University of 8 * Cambridge Computer Laboratory (Department of Computer Science and 9 * Technology) under DARPA contract HR0011-18-C-0016 ("ECATS"), as part of the 10 * DARPA SSITH research programme. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #include <sys/param.h> 38 #include <sys/systm.h> 39 #include <sys/bus.h> 40 #include <sys/kernel.h> 41 #include <sys/ktr.h> 42 #include <sys/module.h> 43 #include <sys/proc.h> 44 #include <sys/rman.h> 45 46 #include <machine/bus.h> 47 #include <machine/intr.h> 48 49 #include <dev/ofw/openfirm.h> 50 #include <dev/ofw/ofw_bus.h> 51 #include <dev/ofw/ofw_bus_subr.h> 52 53 #include "pic_if.h" 54 55 #define PLIC_MAX_IRQS 2048 56 #define PLIC_PRIORITY(n) (0x000000 + (n) * 0x4) 57 #define PLIC_ENABLE(n, h) (0x002000 + (h) * 0x80 + 4 * ((n) / 32)) 58 #define PLIC_THRESHOLD(h) (0x200000 + (h) * 0x1000 + 0x0) 59 #define PLIC_CLAIM(h) (0x200000 + (h) * 0x1000 + 0x4) 60 61 struct plic_irqsrc { 62 struct intr_irqsrc isrc; 63 u_int irq; 64 }; 65 66 struct plic_softc { 67 device_t dev; 68 struct resource * intc_res; 69 struct plic_irqsrc isrcs[PLIC_MAX_IRQS]; 70 int ndev; 71 }; 72 73 #define RD4(sc, reg) \ 74 bus_read_4(sc->intc_res, (reg)) 75 #define WR4(sc, reg, val) \ 76 bus_write_4(sc->intc_res, (reg), (val)) 77 78 static inline void 79 plic_irq_dispatch(struct plic_softc *sc, u_int irq, 80 struct trapframe *tf) 81 { 82 struct plic_irqsrc *src; 83 84 src = &sc->isrcs[irq]; 85 86 if (intr_isrc_dispatch(&src->isrc, tf) != 0) 87 device_printf(sc->dev, "Stray irq %u detected\n", irq); 88 } 89 90 static int 91 plic_intr(void *arg) 92 { 93 struct plic_softc *sc; 94 struct trapframe *tf; 95 uint32_t pending; 96 uint32_t cpu; 97 98 sc = arg; 99 cpu = PCPU_GET(cpuid); 100 101 pending = RD4(sc, PLIC_CLAIM(cpu)); 102 if (pending) { 103 tf = curthread->td_intr_frame; 104 plic_irq_dispatch(sc, pending, tf); 105 WR4(sc, PLIC_CLAIM(cpu), pending); 106 } 107 108 return (FILTER_HANDLED); 109 } 110 111 static void 112 plic_disable_intr(device_t dev, struct intr_irqsrc *isrc) 113 { 114 struct plic_softc *sc; 115 struct plic_irqsrc *src; 116 uint32_t reg; 117 uint32_t cpu; 118 119 sc = device_get_softc(dev); 120 src = (struct plic_irqsrc *)isrc; 121 122 cpu = PCPU_GET(cpuid); 123 124 reg = RD4(sc, PLIC_ENABLE(src->irq, cpu)); 125 reg &= ~(1 << (src->irq % 32)); 126 WR4(sc, PLIC_ENABLE(src->irq, cpu), reg); 127 } 128 129 static void 130 plic_enable_intr(device_t dev, struct intr_irqsrc *isrc) 131 { 132 struct plic_softc *sc; 133 struct plic_irqsrc *src; 134 uint32_t reg; 135 uint32_t cpu; 136 137 sc = device_get_softc(dev); 138 src = (struct plic_irqsrc *)isrc; 139 140 WR4(sc, PLIC_PRIORITY(src->irq), 1); 141 142 cpu = PCPU_GET(cpuid); 143 144 reg = RD4(sc, PLIC_ENABLE(src->irq, cpu)); 145 reg |= (1 << (src->irq % 32)); 146 WR4(sc, PLIC_ENABLE(src->irq, cpu), reg); 147 } 148 149 static int 150 plic_map_intr(device_t dev, struct intr_map_data *data, 151 struct intr_irqsrc **isrcp) 152 { 153 struct intr_map_data_fdt *daf; 154 struct plic_softc *sc; 155 156 sc = device_get_softc(dev); 157 158 if (data->type != INTR_MAP_DATA_FDT) 159 return (ENOTSUP); 160 161 daf = (struct intr_map_data_fdt *)data; 162 if (daf->ncells != 1 || daf->cells[0] > sc->ndev) 163 return (EINVAL); 164 165 *isrcp = &sc->isrcs[daf->cells[0]].isrc; 166 167 return (0); 168 } 169 170 static int 171 plic_probe(device_t dev) 172 { 173 174 if (!ofw_bus_status_okay(dev)) 175 return (ENXIO); 176 177 if (!ofw_bus_is_compatible(dev, "riscv,plic0")) 178 return (ENXIO); 179 180 device_set_desc(dev, "RISC-V PLIC"); 181 182 return (BUS_PROBE_DEFAULT); 183 } 184 185 static int 186 plic_attach(device_t dev) 187 { 188 struct plic_irqsrc *isrcs; 189 struct plic_softc *sc; 190 struct intr_pic *pic; 191 uint32_t irq; 192 const char *name; 193 phandle_t node; 194 phandle_t xref; 195 uint32_t cpu; 196 int error; 197 int rid; 198 199 sc = device_get_softc(dev); 200 201 sc->dev = dev; 202 203 node = ofw_bus_get_node(dev); 204 if ((OF_getencprop(node, "riscv,ndev", &sc->ndev, 205 sizeof(sc->ndev))) < 0) { 206 device_printf(dev, 207 "Error: could not get number of devices\n"); 208 return (ENXIO); 209 } 210 211 if (sc->ndev >= PLIC_MAX_IRQS) { 212 device_printf(dev, 213 "Error: invalid ndev (%d)\n", sc->ndev); 214 return (ENXIO); 215 } 216 217 /* Request memory resources */ 218 rid = 0; 219 sc->intc_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, 220 RF_ACTIVE); 221 if (sc->intc_res == NULL) { 222 device_printf(dev, 223 "Error: could not allocate memory resources\n"); 224 return (ENXIO); 225 } 226 227 isrcs = sc->isrcs; 228 name = device_get_nameunit(sc->dev); 229 cpu = PCPU_GET(cpuid); 230 for (irq = 1; irq <= sc->ndev; irq++) { 231 isrcs[irq].irq = irq; 232 error = intr_isrc_register(&isrcs[irq].isrc, sc->dev, 233 0, "%s,%u", name, irq); 234 if (error != 0) 235 return (error); 236 237 WR4(sc, PLIC_PRIORITY(irq), 0); 238 WR4(sc, PLIC_ENABLE(irq, cpu), 0); 239 } 240 WR4(sc, PLIC_THRESHOLD(cpu), 0); 241 242 xref = OF_xref_from_node(node); 243 pic = intr_pic_register(sc->dev, xref); 244 if (pic == NULL) 245 return (ENXIO); 246 247 csr_set(sie, SIE_SEIE); 248 249 return (intr_pic_claim_root(sc->dev, xref, plic_intr, sc, 0)); 250 } 251 252 static device_method_t plic_methods[] = { 253 DEVMETHOD(device_probe, plic_probe), 254 DEVMETHOD(device_attach, plic_attach), 255 256 DEVMETHOD(pic_disable_intr, plic_disable_intr), 257 DEVMETHOD(pic_enable_intr, plic_enable_intr), 258 DEVMETHOD(pic_map_intr, plic_map_intr), 259 260 DEVMETHOD_END 261 }; 262 263 static driver_t plic_driver = { 264 "plic", 265 plic_methods, 266 sizeof(struct plic_softc), 267 }; 268 269 static devclass_t plic_devclass; 270 271 EARLY_DRIVER_MODULE(plic, simplebus, plic_driver, plic_devclass, 272 0, 0, BUS_PASS_INTERRUPT + BUS_PASS_ORDER_MIDDLE); 273