Arun Kumar Neelakantam | ec35281 | 2018-06-11 18:32:20 +0530 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | /* Copyright (c) 2018, The Linux Foundation. All rights reserved. |
| 3 | */ |
| 4 | |
| 5 | #include <linux/delay.h> |
| 6 | #include <linux/interrupt.h> |
| 7 | #include <linux/ipc_router_xprt.h> |
| 8 | #include <linux/io.h> |
| 9 | #include <linux/of_device.h> |
| 10 | #include <linux/module.h> |
| 11 | #include <linux/platform_device.h> |
| 12 | #include <linux/types.h> |
| 13 | #include <linux/skbuff.h> |
| 14 | #include <linux/sched.h> |
Arun Kumar Neelakantam | 5b37df6 | 2018-07-12 17:39:37 +0530 | [diff] [blame] | 15 | #include <microvisor/microvisor.h> |
Arun Kumar Neelakantam | ec35281 | 2018-06-11 18:32:20 +0530 | [diff] [blame] | 16 | |
| 17 | #define MODULE_NAME "ipc_router_fifo_xprt" |
| 18 | #define XPRT_NAME_LEN 32 |
| 19 | |
| 20 | #define FIFO_MAGIC_KEY 0x24495043 /* "$IPC" */ |
| 21 | #define FIFO_SIZE 0x4000 |
| 22 | #define FIFO_0_START 0x1000 |
| 23 | #define FIFO_1_START (FIFO_0_START + FIFO_SIZE) |
| 24 | #define FIFO_MAGIC_IDX 0x0 |
| 25 | #define TAIL_0_IDX 0x1 |
| 26 | #define HEAD_0_IDX 0x2 |
| 27 | #define TAIL_1_IDX 0x3 |
| 28 | #define HEAD_1_IDX 0x4 |
| 29 | |
| 30 | struct msm_ipc_pipe { |
| 31 | __le32 *tail; |
| 32 | __le32 *head; |
| 33 | |
| 34 | void *fifo; |
| 35 | size_t length; |
| 36 | }; |
| 37 | |
| 38 | /** |
| 39 | * ipcr_fifo_xprt - IPC Router's FIFO XPRT structure |
| 40 | * @xprt: IPC Router XPRT structure to contain XPRT specific info. |
| 41 | * @tx_pipe: TX FIFO specific info. |
| 42 | * @rx_pipe: RX FIFO specific info. |
| 43 | * @fifo_xprt_wq: Workqueue to queue read & other XPRT related works. |
| 44 | * @in_pkt: Pointer to any partially read packet. |
| 45 | * @read_work: Read Work to perform read operation from SMD. |
| 46 | * @sft_close_complete: Variable to indicate completion of SSR handling |
| 47 | * by IPC Router. |
| 48 | * @xprt_version: IPC Router header version supported by this XPRT. |
| 49 | * @driver: Platform drivers register by this XPRT. |
| 50 | * @xprt_name: Name of the XPRT to be registered with IPC Router. |
| 51 | */ |
| 52 | struct ipcr_fifo_xprt { |
| 53 | struct msm_ipc_router_xprt xprt; |
| 54 | struct msm_ipc_pipe tx_pipe; |
| 55 | struct msm_ipc_pipe rx_pipe; |
| 56 | struct workqueue_struct *xprt_wq; |
| 57 | struct rr_packet *in_pkt; |
| 58 | struct delayed_work read_work; |
| 59 | struct completion sft_close_complete; |
| 60 | unsigned int xprt_version; |
| 61 | struct platform_driver driver; |
| 62 | char xprt_name[XPRT_NAME_LEN]; |
| 63 | void *fifo_base; |
| 64 | size_t fifo_size; |
| 65 | int tx_fifo_idx; |
| 66 | okl4_kcap_t kcap; |
| 67 | }; |
| 68 | |
| 69 | static void xprt_read_data(struct work_struct *work); |
| 70 | static void ipcr_fifo_raise_virq(struct ipcr_fifo_xprt *xprtp); |
| 71 | |
| 72 | static size_t fifo_rx_avail(struct msm_ipc_pipe *pipe) |
| 73 | { |
| 74 | u32 head; |
| 75 | u32 tail; |
| 76 | |
| 77 | head = le32_to_cpu(*pipe->head); |
| 78 | tail = le32_to_cpu(*pipe->tail); |
| 79 | |
| 80 | if (head < tail) |
| 81 | return pipe->length - tail + head; |
| 82 | |
| 83 | return head - tail; |
| 84 | } |
| 85 | |
| 86 | static void fifo_rx_peak(struct msm_ipc_pipe *pipe, |
| 87 | void *data, unsigned int offset, size_t count) |
| 88 | { |
| 89 | size_t len; |
| 90 | u32 tail; |
| 91 | |
| 92 | tail = le32_to_cpu(*pipe->tail); |
| 93 | tail += offset; |
| 94 | if (tail >= pipe->length) |
| 95 | tail -= pipe->length; |
| 96 | |
| 97 | len = min_t(size_t, count, pipe->length - tail); |
| 98 | if (len) |
| 99 | memcpy_fromio(data, pipe->fifo + tail, len); |
| 100 | |
| 101 | if (len != count) |
| 102 | memcpy_fromio(data + len, pipe->fifo, (count - len)); |
| 103 | } |
| 104 | |
| 105 | static void fifo_rx_advance(struct msm_ipc_pipe *pipe, size_t count) |
| 106 | { |
| 107 | u32 tail; |
| 108 | |
| 109 | tail = le32_to_cpu(*pipe->tail); |
| 110 | |
| 111 | tail += count; |
| 112 | if (tail > pipe->length) |
| 113 | tail -= pipe->length; |
| 114 | |
| 115 | *pipe->tail = cpu_to_le32(tail); |
| 116 | } |
| 117 | |
| 118 | static size_t fifo_tx_avail(struct msm_ipc_pipe *pipe) |
| 119 | { |
| 120 | u32 head; |
| 121 | u32 tail; |
| 122 | u32 avail; |
| 123 | |
| 124 | head = le32_to_cpu(*pipe->head); |
| 125 | tail = le32_to_cpu(*pipe->tail); |
| 126 | |
| 127 | if (tail <= head) |
| 128 | avail = pipe->length - head + tail; |
| 129 | else |
| 130 | avail = tail - head; |
| 131 | |
| 132 | return avail; |
| 133 | } |
| 134 | |
| 135 | static void fifo_tx_write(struct msm_ipc_pipe *pipe, |
| 136 | const void *data, size_t count) |
| 137 | { |
| 138 | size_t len; |
| 139 | u32 head; |
| 140 | |
| 141 | head = le32_to_cpu(*pipe->head); |
| 142 | |
| 143 | len = min_t(size_t, count, pipe->length - head); |
| 144 | if (len) |
| 145 | memcpy_toio(pipe->fifo + head, data, len); |
| 146 | |
| 147 | if (len != count) |
| 148 | memcpy_toio(pipe->fifo, data + len, count - len); |
| 149 | |
| 150 | head += count; |
| 151 | if (head >= pipe->length) |
| 152 | head -= pipe->length; |
| 153 | |
| 154 | /* Ensure ordering of fifo and head update */ |
| 155 | wmb(); |
| 156 | |
| 157 | *pipe->head = cpu_to_le32(head); |
| 158 | } |
| 159 | |
| 160 | /** |
| 161 | * set_xprt_version() - Set IPC Router header version in the transport |
| 162 | * @xprt: Reference to the transport structure. |
| 163 | * @version: The version to be set in transport. |
| 164 | */ |
| 165 | static void set_xprt_version(struct msm_ipc_router_xprt *xprt, |
| 166 | unsigned int version) |
| 167 | { |
| 168 | struct ipcr_fifo_xprt *xprtp; |
| 169 | |
| 170 | if (!xprt) |
| 171 | return; |
| 172 | xprtp = container_of(xprt, struct ipcr_fifo_xprt, xprt); |
| 173 | xprtp->xprt_version = version; |
| 174 | } |
| 175 | |
| 176 | static int get_xprt_version(struct msm_ipc_router_xprt *xprt) |
| 177 | { |
| 178 | struct ipcr_fifo_xprt *xprtp; |
| 179 | |
| 180 | if (!xprt) |
| 181 | return -EINVAL; |
| 182 | xprtp = container_of(xprt, struct ipcr_fifo_xprt, xprt); |
| 183 | return (int)xprtp->xprt_version; |
| 184 | } |
| 185 | |
| 186 | static int get_xprt_option(struct msm_ipc_router_xprt *xprt) |
| 187 | { |
| 188 | /* fragmented data is NOT supported */ |
| 189 | return 0; |
| 190 | } |
| 191 | |
| 192 | static int xprt_close(struct msm_ipc_router_xprt *xprt) |
| 193 | { |
| 194 | return 0; |
| 195 | } |
| 196 | |
| 197 | static void xprt_sft_close_done(struct msm_ipc_router_xprt *xprt) |
| 198 | { |
| 199 | struct ipcr_fifo_xprt *xprtp; |
| 200 | |
| 201 | if (!xprt) |
| 202 | return; |
| 203 | |
| 204 | xprtp = container_of(xprt, struct ipcr_fifo_xprt, xprt); |
| 205 | complete_all(&xprtp->sft_close_complete); |
| 206 | } |
| 207 | |
| 208 | static int xprt_write(void *data, uint32_t len, |
| 209 | struct msm_ipc_router_xprt *xprt) |
| 210 | { |
| 211 | struct rr_packet *pkt = (struct rr_packet *)data; |
| 212 | struct sk_buff *skb; |
| 213 | struct ipcr_fifo_xprt *xprtp; |
| 214 | |
| 215 | xprtp = container_of(xprt, struct ipcr_fifo_xprt, xprt); |
| 216 | |
| 217 | if (!pkt) |
| 218 | return -EINVAL; |
| 219 | |
| 220 | if (!len || pkt->length != len) |
| 221 | return -EINVAL; |
| 222 | |
| 223 | /* TODO: FIFO write : check if we can write full packet at one shot */ |
| 224 | if (skb_queue_len(pkt->pkt_fragment_q) != 1) { |
| 225 | pr_err("IPC router core is given fragmented data\n"); |
| 226 | return -EINVAL; |
| 227 | } |
| 228 | if (fifo_tx_avail(&xprtp->tx_pipe) < len) { |
| 229 | pr_err("No Space in FIFO\n"); |
| 230 | return -EAGAIN; |
| 231 | } |
| 232 | |
| 233 | skb_queue_walk(pkt->pkt_fragment_q, skb) { |
| 234 | fifo_tx_write(&xprtp->tx_pipe, skb->data, skb->len); |
| 235 | } |
| 236 | |
| 237 | ipcr_fifo_raise_virq(xprtp); |
| 238 | |
| 239 | return len; |
| 240 | } |
| 241 | |
| 242 | static void xprt_read_data(struct work_struct *work) |
| 243 | { |
| 244 | void *data; |
| 245 | size_t hdr_len; |
| 246 | size_t rx_avail; |
| 247 | size_t pkt_len; |
| 248 | struct rr_header_v1 hdr; |
| 249 | struct sk_buff *ipc_rtr_pkt; |
| 250 | struct ipcr_fifo_xprt *xprtp; |
| 251 | struct delayed_work *rwork = to_delayed_work(work); |
| 252 | |
| 253 | xprtp = container_of(rwork, struct ipcr_fifo_xprt, read_work); |
| 254 | |
| 255 | hdr_len = sizeof(struct rr_header_v1); |
| 256 | while (1) { |
| 257 | rx_avail = fifo_rx_avail(&xprtp->rx_pipe); |
Arun Kumar Neelakantam | b691251 | 2018-07-19 13:51:39 +0530 | [diff] [blame] | 258 | if (!rx_avail) |
Arun Kumar Neelakantam | ec35281 | 2018-06-11 18:32:20 +0530 | [diff] [blame] | 259 | break; |
| 260 | |
| 261 | fifo_rx_peak(&xprtp->rx_pipe, &hdr, 0, hdr_len); |
| 262 | pkt_len = ipc_router_peek_pkt_size((char *)&hdr); |
| 263 | |
| 264 | if (pkt_len < 0) { |
| 265 | pr_err("%s invalid pkt_len %zu\n", __func__, pkt_len); |
| 266 | break; |
| 267 | } |
| 268 | if (!xprtp->in_pkt) { |
| 269 | xprtp->in_pkt = create_pkt(NULL); |
| 270 | if (!xprtp->in_pkt) |
| 271 | break; |
| 272 | } |
| 273 | ipc_rtr_pkt = alloc_skb(pkt_len, GFP_KERNEL); |
| 274 | if (!ipc_rtr_pkt) { |
| 275 | release_pkt(xprtp->in_pkt); |
| 276 | xprtp->in_pkt = NULL; |
| 277 | break; |
| 278 | } |
| 279 | data = skb_put(ipc_rtr_pkt, pkt_len); |
| 280 | do { |
| 281 | rx_avail = fifo_rx_avail(&xprtp->rx_pipe); |
| 282 | if (rx_avail >= pkt_len) { |
| 283 | fifo_rx_peak(&xprtp->rx_pipe, data, 0, pkt_len); |
| 284 | fifo_rx_advance(&xprtp->rx_pipe, pkt_len); |
| 285 | break; |
| 286 | } |
| 287 | pr_debug("%s wait for FULL PKT [avail: len][%zu:%zu]\n", |
| 288 | __func__, rx_avail, pkt_len); |
| 289 | /* wait for complete packet written into FIFO */ |
| 290 | msleep(20); |
| 291 | } while (1); |
| 292 | |
| 293 | skb_queue_tail(xprtp->in_pkt->pkt_fragment_q, ipc_rtr_pkt); |
| 294 | xprtp->in_pkt->length = pkt_len; |
| 295 | msm_ipc_router_xprt_notify(&xprtp->xprt, |
| 296 | IPC_ROUTER_XPRT_EVENT_DATA, |
| 297 | (void *)xprtp->in_pkt); |
| 298 | release_pkt(xprtp->in_pkt); |
| 299 | xprtp->in_pkt = NULL; |
| 300 | } |
| 301 | } |
| 302 | |
| 303 | static void ipcr_fifo_raise_virq(struct ipcr_fifo_xprt *xprtp) |
| 304 | { |
| 305 | okl4_error_t err; |
| 306 | unsigned long payload = 0xffff; |
| 307 | |
| 308 | err = _okl4_sys_vinterrupt_raise(xprtp->kcap, payload); |
| 309 | } |
| 310 | |
| 311 | static irqreturn_t ipcr_fifo_virq_handler(int irq, void *dev_id) |
| 312 | { |
| 313 | struct ipcr_fifo_xprt *xprtp = dev_id; |
| 314 | |
| 315 | queue_delayed_work(xprtp->xprt_wq, &xprtp->read_work, 0); |
| 316 | return IRQ_HANDLED; |
| 317 | } |
| 318 | |
| 319 | /** |
| 320 | * ipcr_fifo_config_init() - init FIFO xprt configs |
| 321 | * |
| 322 | * @return: 0 on success, standard Linux error codes on error. |
| 323 | * |
| 324 | * This function is called to initialize the FIFO XPRT pointer with |
| 325 | * the FIFO XPRT configurations either from device tree or static arrays. |
| 326 | */ |
| 327 | static int ipcr_fifo_config_init(struct ipcr_fifo_xprt *xprtp) |
| 328 | { |
| 329 | __le32 *descs; |
| 330 | |
| 331 | descs = xprtp->fifo_base; |
| 332 | descs[FIFO_MAGIC_IDX] = FIFO_MAGIC_KEY; |
| 333 | |
| 334 | if (xprtp->tx_fifo_idx) { |
| 335 | xprtp->tx_pipe.tail = &descs[TAIL_0_IDX]; |
| 336 | xprtp->tx_pipe.head = &descs[HEAD_0_IDX]; |
| 337 | xprtp->tx_pipe.fifo = xprtp->fifo_base + FIFO_0_START; |
| 338 | xprtp->tx_pipe.length = FIFO_SIZE; |
| 339 | |
| 340 | xprtp->rx_pipe.tail = &descs[TAIL_1_IDX]; |
| 341 | xprtp->rx_pipe.head = &descs[HEAD_1_IDX]; |
| 342 | xprtp->rx_pipe.fifo = xprtp->fifo_base + FIFO_1_START; |
| 343 | xprtp->rx_pipe.length = FIFO_SIZE; |
| 344 | } else { |
| 345 | xprtp->tx_pipe.tail = &descs[TAIL_1_IDX]; |
| 346 | xprtp->tx_pipe.head = &descs[HEAD_1_IDX]; |
| 347 | xprtp->tx_pipe.fifo = xprtp->fifo_base + FIFO_1_START; |
| 348 | xprtp->tx_pipe.length = FIFO_SIZE; |
| 349 | |
| 350 | xprtp->rx_pipe.tail = &descs[TAIL_0_IDX]; |
| 351 | xprtp->rx_pipe.head = &descs[HEAD_0_IDX]; |
| 352 | xprtp->rx_pipe.fifo = xprtp->fifo_base + FIFO_0_START; |
| 353 | xprtp->rx_pipe.length = FIFO_SIZE; |
| 354 | } |
| 355 | |
| 356 | /* Reset respective index */ |
| 357 | *xprtp->tx_pipe.head = 0; |
| 358 | *xprtp->rx_pipe.tail = 0; |
| 359 | |
| 360 | xprtp->xprt.link_id = 1; |
| 361 | xprtp->xprt_version = 1; |
| 362 | |
| 363 | strlcpy(xprtp->xprt_name, "IPCR_FIFO_XPRT", XPRT_NAME_LEN); |
| 364 | xprtp->xprt.name = xprtp->xprt_name; |
| 365 | |
| 366 | xprtp->xprt.set_version = set_xprt_version; |
| 367 | xprtp->xprt.get_version = get_xprt_version; |
| 368 | xprtp->xprt.get_option = get_xprt_option; |
| 369 | xprtp->xprt.read_avail = NULL; |
| 370 | xprtp->xprt.read = NULL; |
| 371 | xprtp->xprt.write_avail = NULL; |
| 372 | xprtp->xprt.write = xprt_write; |
| 373 | xprtp->xprt.close = xprt_close; |
| 374 | xprtp->xprt.sft_close_done = xprt_sft_close_done; |
| 375 | xprtp->xprt.priv = NULL; |
| 376 | |
| 377 | xprtp->in_pkt = NULL; |
| 378 | xprtp->xprt_wq = create_singlethread_workqueue(xprtp->xprt_name); |
| 379 | if (!xprtp->xprt_wq) |
| 380 | return -EFAULT; |
| 381 | |
| 382 | INIT_DELAYED_WORK(&xprtp->read_work, xprt_read_data); |
| 383 | |
| 384 | msm_ipc_router_xprt_notify(&xprtp->xprt, |
| 385 | IPC_ROUTER_XPRT_EVENT_OPEN, |
| 386 | NULL); |
| 387 | |
| 388 | if (fifo_rx_avail(&xprtp->rx_pipe)) |
| 389 | queue_delayed_work(xprtp->xprt_wq, &xprtp->read_work, 0); |
| 390 | |
| 391 | return 0; |
| 392 | } |
| 393 | |
| 394 | /** |
| 395 | * ipcr_fifo_xprt_probe() - Probe an FIFO xprt |
| 396 | * |
| 397 | * @pdev: Platform device corresponding to FIFO xprt. |
| 398 | * |
| 399 | * @return: 0 on success, standard Linux error codes on error. |
| 400 | * |
| 401 | * This function is called when the underlying device tree driver registers |
| 402 | * a platform device, mapped to an FIFO transport. |
| 403 | */ |
| 404 | static int ipcr_fifo_xprt_probe(struct platform_device *pdev) |
| 405 | { |
| 406 | int irq; |
| 407 | int ret; |
| 408 | struct resource *r; |
| 409 | struct device *parent; |
| 410 | struct ipcr_fifo_xprt *xprtp; |
| 411 | struct device_node *ipc_irq_np; |
| 412 | struct device_node *ipc_shm_np; |
| 413 | struct platform_device *ipc_shm_dev; |
| 414 | |
| 415 | xprtp = devm_kzalloc(&pdev->dev, sizeof(*xprtp), GFP_KERNEL); |
| 416 | if (IS_ERR_OR_NULL(xprtp)) |
| 417 | return -ENOMEM; |
| 418 | |
| 419 | parent = &pdev->dev; |
| 420 | ipc_irq_np = parent->of_node; |
| 421 | |
| 422 | irq = platform_get_irq(pdev, 0); |
| 423 | |
| 424 | if (irq >= 0) { |
| 425 | ret = devm_request_irq(parent, irq, ipcr_fifo_virq_handler, |
| 426 | IRQF_TRIGGER_RISING, dev_name(parent), |
| 427 | xprtp); |
| 428 | if (ret < 0) |
| 429 | return -ENODEV; |
| 430 | } |
| 431 | |
| 432 | /* this kcap is required to raise VIRQ */ |
| 433 | ret = of_property_read_u32(ipc_irq_np, "reg", &xprtp->kcap); |
| 434 | if (ret < 0) |
| 435 | return -ENODEV; |
| 436 | |
| 437 | ipc_shm_np = of_parse_phandle(ipc_irq_np, "qcom,ipc-shm", 0); |
| 438 | if (!ipc_shm_np) |
| 439 | return -ENODEV; |
| 440 | |
| 441 | ipc_shm_dev = of_find_device_by_node(ipc_shm_np); |
| 442 | if (!ipc_shm_dev) |
| 443 | return -ENODEV; |
| 444 | |
| 445 | r = platform_get_resource(ipc_shm_dev, IORESOURCE_MEM, 0); |
| 446 | if (!r) { |
| 447 | pr_err("%s failed to get shared FIFO\n", __func__); |
| 448 | return -ENODEV; |
| 449 | } |
| 450 | |
| 451 | xprtp->tx_fifo_idx = of_property_read_bool(ipc_shm_np, |
| 452 | "qcom,tx-is-first"); |
| 453 | |
| 454 | xprtp->fifo_size = resource_size(r); |
| 455 | xprtp->fifo_base = devm_ioremap_nocache(&pdev->dev, r->start, |
| 456 | resource_size(r)); |
| 457 | if (!xprtp->fifo_base) { |
| 458 | pr_err("%s ioreamp_nocache() failed\n", __func__); |
| 459 | return -ENOMEM; |
| 460 | } |
| 461 | |
| 462 | ret = ipcr_fifo_config_init(xprtp); |
| 463 | if (ret) { |
| 464 | IPC_RTR_ERR("%s init failed ret[%d]\n", __func__, ret); |
| 465 | return ret; |
| 466 | } |
| 467 | |
| 468 | return 0; |
| 469 | } |
| 470 | |
| 471 | static const struct of_device_id ipcr_fifo_xprt_match_table[] = { |
| 472 | { .compatible = "qcom,ipcr-fifo-xprt" }, |
| 473 | {}, |
| 474 | }; |
| 475 | |
| 476 | static struct platform_driver ipcr_fifo_xprt_driver = { |
| 477 | .probe = ipcr_fifo_xprt_probe, |
| 478 | .driver = { |
| 479 | .name = MODULE_NAME, |
| 480 | .owner = THIS_MODULE, |
| 481 | .of_match_table = ipcr_fifo_xprt_match_table, |
| 482 | }, |
| 483 | }; |
| 484 | |
| 485 | static int __init ipcr_fifo_xprt_init(void) |
| 486 | { |
| 487 | int rc; |
| 488 | |
| 489 | rc = platform_driver_register(&ipcr_fifo_xprt_driver); |
| 490 | if (rc) { |
| 491 | IPC_RTR_ERR("%s: driver register failed %d\n", __func__, rc); |
| 492 | return rc; |
| 493 | } |
| 494 | |
| 495 | return 0; |
| 496 | } |
| 497 | |
| 498 | module_init(ipcr_fifo_xprt_init); |
| 499 | MODULE_DESCRIPTION("IPC Router FIFO XPRT"); |
| 500 | MODULE_LICENSE("GPL v2"); |