1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2022 Ruslan Bukin <br@bsdpad.com> 5 * Copyright (c) 2023 Arm Ltd 6 * 7 * This work was supported by Innovate UK project 105694, "Digital Security 8 * by Design (DSbD) Technology Platform Prototype". 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 AUTHOR AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 34 #include <sys/param.h> 35 #include <sys/systm.h> 36 #include <sys/bus.h> 37 #include <sys/cpu.h> 38 #include <sys/kernel.h> 39 #include <sys/module.h> 40 41 #include <dev/fdt/simplebus.h> 42 #include <dev/fdt/fdt_common.h> 43 #include <dev/ofw/ofw_bus_subr.h> 44 45 #include "dev/mailbox/arm/arm_doorbell.h" 46 47 #include "scmi.h" 48 #include "scmi_protocols.h" 49 #include "scmi_shmem.h" 50 51 #define SCMI_MBOX_POLL_INTERVAL_MS 3 52 53 struct scmi_mailbox_softc { 54 struct scmi_softc base; 55 device_t a2p_dev; 56 struct arm_doorbell *db; 57 }; 58 59 static int scmi_mailbox_transport_init(device_t); 60 static void scmi_mailbox_transport_cleanup(device_t); 61 static int scmi_mailbox_xfer_msg(device_t, struct scmi_msg *); 62 static int scmi_mailbox_poll_msg(device_t, struct scmi_msg *, 63 unsigned int); 64 static int scmi_mailbox_collect_reply(device_t, struct scmi_msg *); 65 static void scmi_mailbox_tx_complete(device_t, void *); 66 67 static int scmi_mailbox_probe(device_t); 68 69 static void 70 scmi_mailbox_a2p_callback(void *arg) 71 { 72 struct scmi_mailbox_softc *sc; 73 uint32_t msg_header; 74 int ret; 75 76 sc = arg; 77 78 ret = scmi_shmem_read_msg_header(sc->a2p_dev, &msg_header); 79 if (ret == 0) 80 scmi_rx_irq_callback(sc->base.dev, sc->a2p_dev, msg_header); 81 } 82 83 static int 84 scmi_mailbox_transport_init(device_t dev) 85 { 86 struct scmi_mailbox_softc *sc; 87 phandle_t node; 88 89 sc = device_get_softc(dev); 90 91 node = ofw_bus_get_node(dev); 92 if (node == -1) 93 return (ENXIO); 94 /* 95 * TODO 96 * - Support P2A shmem + IRQ/doorbell 97 * - Support other mailbox devices 98 */ 99 sc->a2p_dev = scmi_shmem_get(dev, node, SCMI_CHAN_A2P); 100 if (sc->a2p_dev == NULL) { 101 device_printf(dev, "A2P shmem dev not found.\n"); 102 return (ENXIO); 103 } 104 105 /* TODO: Fix ofw_get...mbox doorbell names NOT required in Linux DT */ 106 sc->db = arm_doorbell_ofw_get(dev, "tx"); 107 if (sc->db == NULL) { 108 device_printf(dev, "Doorbell device not found.\n"); 109 return (ENXIO); 110 } 111 112 sc->base.trs_desc.reply_timo_ms = 30; 113 114 arm_doorbell_set_handler(sc->db, scmi_mailbox_a2p_callback, sc); 115 116 return (0); 117 } 118 119 static void 120 scmi_mailbox_transport_cleanup(device_t dev) 121 { 122 struct scmi_mailbox_softc *sc; 123 124 sc = device_get_softc(dev); 125 126 arm_doorbell_set_handler(sc->db, NULL, NULL); 127 } 128 129 static int 130 scmi_mailbox_xfer_msg(device_t dev, struct scmi_msg *msg) 131 { 132 struct scmi_mailbox_softc *sc; 133 int ret; 134 135 sc = device_get_softc(dev); 136 137 ret = scmi_shmem_prepare_msg(sc->a2p_dev, (uint8_t *)&msg->hdr, 138 msg->tx_len, msg->polling); 139 if (ret != 0) 140 return (ret); 141 142 /* Interrupt SCP firmware. */ 143 arm_doorbell_set(sc->db); 144 145 return (0); 146 } 147 148 static int 149 scmi_mailbox_poll_msg(device_t dev, struct scmi_msg *msg, unsigned int tmo_ms) 150 { 151 struct scmi_mailbox_softc *sc; 152 unsigned int tmo_loops = tmo_ms / SCMI_MBOX_POLL_INTERVAL_MS; 153 154 sc = device_get_softc(dev); 155 156 do { 157 if (scmi_shmem_poll_msg(sc->a2p_dev, &msg->hdr)) 158 break; 159 DELAY(SCMI_MBOX_POLL_INTERVAL_MS * 1000); 160 } while (tmo_loops--); 161 162 return (tmo_loops ? 0 : 1); 163 } 164 165 static int 166 scmi_mailbox_collect_reply(device_t dev, struct scmi_msg *msg) 167 { 168 struct scmi_mailbox_softc *sc; 169 int ret; 170 171 sc = device_get_softc(dev); 172 173 ret = scmi_shmem_read_msg_payload(sc->a2p_dev, 174 msg->payld, msg->rx_len - SCMI_MSG_HDR_SIZE); 175 176 return (ret); 177 } 178 179 static void 180 scmi_mailbox_tx_complete(device_t dev, void *chan) 181 { 182 struct scmi_mailbox_softc *sc; 183 184 sc = device_get_softc(dev); 185 scmi_shmem_tx_complete(sc->a2p_dev); 186 } 187 188 static void 189 scmi_mailbox_clear_channel(device_t dev, void *chan) 190 { 191 /* Only P2A channel can be cleared forcibly by agent */ 192 scmi_shmem_clear_channel(chan); 193 } 194 195 static int 196 scmi_mailbox_probe(device_t dev) 197 { 198 199 if (!ofw_bus_is_compatible(dev, "arm,scmi")) 200 return (ENXIO); 201 202 if (!ofw_bus_status_okay(dev)) 203 return (ENXIO); 204 205 device_set_desc(dev, "ARM SCMI Mailbox Transport driver"); 206 207 return (BUS_PROBE_DEFAULT); 208 } 209 210 static device_method_t scmi_mailbox_methods[] = { 211 DEVMETHOD(device_probe, scmi_mailbox_probe), 212 213 /* SCMI interface */ 214 DEVMETHOD(scmi_transport_init, scmi_mailbox_transport_init), 215 DEVMETHOD(scmi_transport_cleanup, scmi_mailbox_transport_cleanup), 216 DEVMETHOD(scmi_xfer_msg, scmi_mailbox_xfer_msg), 217 DEVMETHOD(scmi_poll_msg, scmi_mailbox_poll_msg), 218 DEVMETHOD(scmi_collect_reply, scmi_mailbox_collect_reply), 219 DEVMETHOD(scmi_tx_complete, scmi_mailbox_tx_complete), 220 DEVMETHOD(scmi_clear_channel, scmi_mailbox_clear_channel), 221 222 DEVMETHOD_END 223 }; 224 225 DEFINE_CLASS_1(scmi_mailbox, scmi_mailbox_driver, scmi_mailbox_methods, 226 sizeof(struct scmi_mailbox_softc), scmi_driver); 227 228 DRIVER_MODULE(scmi_mailbox, simplebus, scmi_mailbox_driver, 0, 0); 229 MODULE_VERSION(scmi_mailbox, 1); 230