720 lines · c
1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * nosy - Snoop mode driver for TI PCILynx 1394 controllers4 * Copyright (C) 2002-2007 Kristian Høgsberg5 */6 7#include <linux/device.h>8#include <linux/errno.h>9#include <linux/fs.h>10#include <linux/init.h>11#include <linux/interrupt.h>12#include <linux/io.h>13#include <linux/kernel.h>14#include <linux/kref.h>15#include <linux/miscdevice.h>16#include <linux/module.h>17#include <linux/mutex.h>18#include <linux/pci.h>19#include <linux/poll.h>20#include <linux/sched.h> /* required for linux/wait.h */21#include <linux/slab.h>22#include <linux/spinlock.h>23#include <linux/time64.h>24#include <linux/timex.h>25#include <linux/uaccess.h>26#include <linux/wait.h>27#include <linux/dma-mapping.h>28#include <linux/atomic.h>29#include <asm/byteorder.h>30 31#include "nosy.h"32#include "nosy-user.h"33 34#define TCODE_PHY_PACKET 0x1035#define PCI_DEVICE_ID_TI_PCILYNX 0x800036 37static char driver_name[] = KBUILD_MODNAME;38 39/* this is the physical layout of a PCL, its size is 128 bytes */40struct pcl {41 __le32 next;42 __le32 async_error_next;43 u32 user_data;44 __le32 pcl_status;45 __le32 remaining_transfer_count;46 __le32 next_data_buffer;47 struct {48 __le32 control;49 __le32 pointer;50 } buffer[13];51};52 53struct packet {54 unsigned int length;55 char data[];56};57 58struct packet_buffer {59 char *data;60 size_t capacity;61 long total_packet_count, lost_packet_count;62 atomic_t size;63 struct packet *head, *tail;64 wait_queue_head_t wait;65};66 67struct pcilynx {68 struct pci_dev *pci_device;69 __iomem char *registers;70 71 struct pcl *rcv_start_pcl, *rcv_pcl;72 __le32 *rcv_buffer;73 74 dma_addr_t rcv_start_pcl_bus, rcv_pcl_bus, rcv_buffer_bus;75 76 spinlock_t client_list_lock;77 struct list_head client_list;78 79 struct miscdevice misc;80 struct list_head link;81 struct kref kref;82};83 84static inline struct pcilynx *85lynx_get(struct pcilynx *lynx)86{87 kref_get(&lynx->kref);88 89 return lynx;90}91 92static void93lynx_release(struct kref *kref)94{95 kfree(container_of(kref, struct pcilynx, kref));96}97 98static inline void99lynx_put(struct pcilynx *lynx)100{101 kref_put(&lynx->kref, lynx_release);102}103 104struct client {105 struct pcilynx *lynx;106 u32 tcode_mask;107 struct packet_buffer buffer;108 struct list_head link;109};110 111static DEFINE_MUTEX(card_mutex);112static LIST_HEAD(card_list);113 114static int115packet_buffer_init(struct packet_buffer *buffer, size_t capacity)116{117 buffer->data = kmalloc(capacity, GFP_KERNEL);118 if (buffer->data == NULL)119 return -ENOMEM;120 buffer->head = (struct packet *) buffer->data;121 buffer->tail = (struct packet *) buffer->data;122 buffer->capacity = capacity;123 buffer->lost_packet_count = 0;124 atomic_set(&buffer->size, 0);125 init_waitqueue_head(&buffer->wait);126 127 return 0;128}129 130static void131packet_buffer_destroy(struct packet_buffer *buffer)132{133 kfree(buffer->data);134}135 136static int137packet_buffer_get(struct client *client, char __user *data, size_t user_length)138{139 struct packet_buffer *buffer = &client->buffer;140 size_t length;141 char *end;142 143 if (wait_event_interruptible(buffer->wait,144 atomic_read(&buffer->size) > 0) ||145 list_empty(&client->lynx->link))146 return -ERESTARTSYS;147 148 if (atomic_read(&buffer->size) == 0)149 return -ENODEV;150 151 length = buffer->head->length;152 153 if (length > user_length)154 return 0;155 156 end = buffer->data + buffer->capacity;157 158 if (&buffer->head->data[length] < end) {159 if (copy_to_user(data, buffer->head->data, length))160 return -EFAULT;161 buffer->head = (struct packet *) &buffer->head->data[length];162 } else {163 size_t split = end - buffer->head->data;164 165 if (copy_to_user(data, buffer->head->data, split))166 return -EFAULT;167 if (copy_to_user(data + split, buffer->data, length - split))168 return -EFAULT;169 buffer->head = (struct packet *) &buffer->data[length - split];170 }171 172 /*173 * Decrease buffer->size as the last thing, since this is what174 * keeps the interrupt from overwriting the packet we are175 * retrieving from the buffer.176 */177 atomic_sub(sizeof(struct packet) + length, &buffer->size);178 179 return length;180}181 182static void183packet_buffer_put(struct packet_buffer *buffer, void *data, size_t length)184{185 char *end;186 187 buffer->total_packet_count++;188 189 if (buffer->capacity <190 atomic_read(&buffer->size) + sizeof(struct packet) + length) {191 buffer->lost_packet_count++;192 return;193 }194 195 end = buffer->data + buffer->capacity;196 buffer->tail->length = length;197 198 if (&buffer->tail->data[length] < end) {199 memcpy(buffer->tail->data, data, length);200 buffer->tail = (struct packet *) &buffer->tail->data[length];201 } else {202 size_t split = end - buffer->tail->data;203 204 memcpy(buffer->tail->data, data, split);205 memcpy(buffer->data, data + split, length - split);206 buffer->tail = (struct packet *) &buffer->data[length - split];207 }208 209 /* Finally, adjust buffer size and wake up userspace reader. */210 211 atomic_add(sizeof(struct packet) + length, &buffer->size);212 wake_up_interruptible(&buffer->wait);213}214 215static inline void216reg_write(struct pcilynx *lynx, int offset, u32 data)217{218 writel(data, lynx->registers + offset);219}220 221static inline u32222reg_read(struct pcilynx *lynx, int offset)223{224 return readl(lynx->registers + offset);225}226 227static inline void228reg_set_bits(struct pcilynx *lynx, int offset, u32 mask)229{230 reg_write(lynx, offset, (reg_read(lynx, offset) | mask));231}232 233/*234 * Maybe the pcl programs could be set up to just append data instead235 * of using a whole packet.236 */237static inline void238run_pcl(struct pcilynx *lynx, dma_addr_t pcl_bus,239 int dmachan)240{241 reg_write(lynx, DMA0_CURRENT_PCL + dmachan * 0x20, pcl_bus);242 reg_write(lynx, DMA0_CHAN_CTRL + dmachan * 0x20,243 DMA_CHAN_CTRL_ENABLE | DMA_CHAN_CTRL_LINK);244}245 246static int247set_phy_reg(struct pcilynx *lynx, int addr, int val)248{249 if (addr > 15) {250 dev_err(&lynx->pci_device->dev,251 "PHY register address %d out of range\n", addr);252 return -1;253 }254 if (val > 0xff) {255 dev_err(&lynx->pci_device->dev,256 "PHY register value %d out of range\n", val);257 return -1;258 }259 reg_write(lynx, LINK_PHY, LINK_PHY_WRITE |260 LINK_PHY_ADDR(addr) | LINK_PHY_WDATA(val));261 262 return 0;263}264 265static int266nosy_open(struct inode *inode, struct file *file)267{268 int minor = iminor(inode);269 struct client *client;270 struct pcilynx *tmp, *lynx = NULL;271 272 mutex_lock(&card_mutex);273 list_for_each_entry(tmp, &card_list, link)274 if (tmp->misc.minor == minor) {275 lynx = lynx_get(tmp);276 break;277 }278 mutex_unlock(&card_mutex);279 if (lynx == NULL)280 return -ENODEV;281 282 client = kmalloc(sizeof *client, GFP_KERNEL);283 if (client == NULL)284 goto fail;285 286 client->tcode_mask = ~0;287 client->lynx = lynx;288 INIT_LIST_HEAD(&client->link);289 290 if (packet_buffer_init(&client->buffer, 128 * 1024) < 0)291 goto fail;292 293 file->private_data = client;294 295 return stream_open(inode, file);296fail:297 kfree(client);298 lynx_put(lynx);299 300 return -ENOMEM;301}302 303static int304nosy_release(struct inode *inode, struct file *file)305{306 struct client *client = file->private_data;307 struct pcilynx *lynx = client->lynx;308 309 spin_lock_irq(&lynx->client_list_lock);310 list_del_init(&client->link);311 spin_unlock_irq(&lynx->client_list_lock);312 313 packet_buffer_destroy(&client->buffer);314 kfree(client);315 lynx_put(lynx);316 317 return 0;318}319 320static __poll_t321nosy_poll(struct file *file, poll_table *pt)322{323 struct client *client = file->private_data;324 __poll_t ret = 0;325 326 poll_wait(file, &client->buffer.wait, pt);327 328 if (atomic_read(&client->buffer.size) > 0)329 ret = EPOLLIN | EPOLLRDNORM;330 331 if (list_empty(&client->lynx->link))332 ret |= EPOLLHUP;333 334 return ret;335}336 337static ssize_t338nosy_read(struct file *file, char __user *buffer, size_t count, loff_t *offset)339{340 struct client *client = file->private_data;341 342 return packet_buffer_get(client, buffer, count);343}344 345static long346nosy_ioctl(struct file *file, unsigned int cmd, unsigned long arg)347{348 struct client *client = file->private_data;349 spinlock_t *client_list_lock = &client->lynx->client_list_lock;350 struct nosy_stats stats;351 int ret;352 353 switch (cmd) {354 case NOSY_IOC_GET_STATS:355 spin_lock_irq(client_list_lock);356 stats.total_packet_count = client->buffer.total_packet_count;357 stats.lost_packet_count = client->buffer.lost_packet_count;358 spin_unlock_irq(client_list_lock);359 360 if (copy_to_user((void __user *) arg, &stats, sizeof stats))361 return -EFAULT;362 else363 return 0;364 365 case NOSY_IOC_START:366 ret = -EBUSY;367 spin_lock_irq(client_list_lock);368 if (list_empty(&client->link)) {369 list_add_tail(&client->link, &client->lynx->client_list);370 ret = 0;371 }372 spin_unlock_irq(client_list_lock);373 374 return ret;375 376 case NOSY_IOC_STOP:377 spin_lock_irq(client_list_lock);378 list_del_init(&client->link);379 spin_unlock_irq(client_list_lock);380 381 return 0;382 383 case NOSY_IOC_FILTER:384 spin_lock_irq(client_list_lock);385 client->tcode_mask = arg;386 spin_unlock_irq(client_list_lock);387 388 return 0;389 390 default:391 return -EINVAL;392 /* Flush buffer, configure filter. */393 }394}395 396static const struct file_operations nosy_ops = {397 .owner = THIS_MODULE,398 .read = nosy_read,399 .unlocked_ioctl = nosy_ioctl,400 .poll = nosy_poll,401 .open = nosy_open,402 .release = nosy_release,403};404 405#define PHY_PACKET_SIZE 12 /* 1 payload, 1 inverse, 1 ack = 3 quadlets */406 407static void408packet_irq_handler(struct pcilynx *lynx)409{410 struct client *client;411 u32 tcode_mask, tcode, timestamp;412 size_t length;413 struct timespec64 ts64;414 415 /* FIXME: Also report rcv_speed. */416 417 length = __le32_to_cpu(lynx->rcv_pcl->pcl_status) & 0x00001fff;418 tcode = __le32_to_cpu(lynx->rcv_buffer[1]) >> 4 & 0xf;419 420 ktime_get_real_ts64(&ts64);421 timestamp = ts64.tv_nsec / NSEC_PER_USEC;422 lynx->rcv_buffer[0] = (__force __le32)timestamp;423 424 if (length == PHY_PACKET_SIZE)425 tcode_mask = 1 << TCODE_PHY_PACKET;426 else427 tcode_mask = 1 << tcode;428 429 spin_lock(&lynx->client_list_lock);430 431 list_for_each_entry(client, &lynx->client_list, link)432 if (client->tcode_mask & tcode_mask)433 packet_buffer_put(&client->buffer,434 lynx->rcv_buffer, length + 4);435 436 spin_unlock(&lynx->client_list_lock);437}438 439static void440bus_reset_irq_handler(struct pcilynx *lynx)441{442 struct client *client;443 struct timespec64 ts64;444 u32 timestamp;445 446 ktime_get_real_ts64(&ts64);447 timestamp = ts64.tv_nsec / NSEC_PER_USEC;448 449 spin_lock(&lynx->client_list_lock);450 451 list_for_each_entry(client, &lynx->client_list, link)452 packet_buffer_put(&client->buffer, ×tamp, 4);453 454 spin_unlock(&lynx->client_list_lock);455}456 457static irqreturn_t458irq_handler(int irq, void *device)459{460 struct pcilynx *lynx = device;461 u32 pci_int_status;462 463 pci_int_status = reg_read(lynx, PCI_INT_STATUS);464 465 if (pci_int_status == ~0)466 /* Card was ejected. */467 return IRQ_NONE;468 469 if ((pci_int_status & PCI_INT_INT_PEND) == 0)470 /* Not our interrupt, bail out quickly. */471 return IRQ_NONE;472 473 if ((pci_int_status & PCI_INT_P1394_INT) != 0) {474 u32 link_int_status;475 476 link_int_status = reg_read(lynx, LINK_INT_STATUS);477 reg_write(lynx, LINK_INT_STATUS, link_int_status);478 479 if ((link_int_status & LINK_INT_PHY_BUSRESET) > 0)480 bus_reset_irq_handler(lynx);481 }482 483 /* Clear the PCI_INT_STATUS register only after clearing the484 * LINK_INT_STATUS register; otherwise the PCI_INT_P1394 will485 * be set again immediately. */486 487 reg_write(lynx, PCI_INT_STATUS, pci_int_status);488 489 if ((pci_int_status & PCI_INT_DMA0_HLT) > 0) {490 packet_irq_handler(lynx);491 run_pcl(lynx, lynx->rcv_start_pcl_bus, 0);492 }493 494 return IRQ_HANDLED;495}496 497static void498remove_card(struct pci_dev *dev)499{500 struct pcilynx *lynx = pci_get_drvdata(dev);501 struct client *client;502 503 mutex_lock(&card_mutex);504 list_del_init(&lynx->link);505 misc_deregister(&lynx->misc);506 mutex_unlock(&card_mutex);507 508 reg_write(lynx, PCI_INT_ENABLE, 0);509 free_irq(lynx->pci_device->irq, lynx);510 511 spin_lock_irq(&lynx->client_list_lock);512 list_for_each_entry(client, &lynx->client_list, link)513 wake_up_interruptible(&client->buffer.wait);514 spin_unlock_irq(&lynx->client_list_lock);515 516 dma_free_coherent(&lynx->pci_device->dev, sizeof(struct pcl),517 lynx->rcv_start_pcl, lynx->rcv_start_pcl_bus);518 dma_free_coherent(&lynx->pci_device->dev, sizeof(struct pcl),519 lynx->rcv_pcl, lynx->rcv_pcl_bus);520 dma_free_coherent(&lynx->pci_device->dev, PAGE_SIZE, lynx->rcv_buffer,521 lynx->rcv_buffer_bus);522 523 iounmap(lynx->registers);524 pci_disable_device(dev);525 lynx_put(lynx);526}527 528#define RCV_BUFFER_SIZE (16 * 1024)529 530static int531add_card(struct pci_dev *dev, const struct pci_device_id *unused)532{533 struct pcilynx *lynx;534 u32 p, end;535 int ret, i;536 537 if (dma_set_mask(&dev->dev, DMA_BIT_MASK(32))) {538 dev_err(&dev->dev,539 "DMA address limits not supported for PCILynx hardware\n");540 return -ENXIO;541 }542 if (pci_enable_device(dev)) {543 dev_err(&dev->dev, "Failed to enable PCILynx hardware\n");544 return -ENXIO;545 }546 pci_set_master(dev);547 548 lynx = kzalloc(sizeof *lynx, GFP_KERNEL);549 if (lynx == NULL) {550 dev_err(&dev->dev, "Failed to allocate control structure\n");551 ret = -ENOMEM;552 goto fail_disable;553 }554 lynx->pci_device = dev;555 pci_set_drvdata(dev, lynx);556 557 spin_lock_init(&lynx->client_list_lock);558 INIT_LIST_HEAD(&lynx->client_list);559 kref_init(&lynx->kref);560 561 lynx->registers = ioremap(pci_resource_start(dev, 0),562 PCILYNX_MAX_REGISTER);563 if (lynx->registers == NULL) {564 dev_err(&dev->dev, "Failed to map registers\n");565 ret = -ENOMEM;566 goto fail_deallocate_lynx;567 }568 569 lynx->rcv_start_pcl = dma_alloc_coherent(&lynx->pci_device->dev,570 sizeof(struct pcl),571 &lynx->rcv_start_pcl_bus,572 GFP_KERNEL);573 lynx->rcv_pcl = dma_alloc_coherent(&lynx->pci_device->dev,574 sizeof(struct pcl),575 &lynx->rcv_pcl_bus, GFP_KERNEL);576 lynx->rcv_buffer = dma_alloc_coherent(&lynx->pci_device->dev,577 RCV_BUFFER_SIZE,578 &lynx->rcv_buffer_bus, GFP_KERNEL);579 if (lynx->rcv_start_pcl == NULL ||580 lynx->rcv_pcl == NULL ||581 lynx->rcv_buffer == NULL) {582 dev_err(&dev->dev, "Failed to allocate receive buffer\n");583 ret = -ENOMEM;584 goto fail_deallocate_buffers;585 }586 lynx->rcv_start_pcl->next = cpu_to_le32(lynx->rcv_pcl_bus);587 lynx->rcv_pcl->next = cpu_to_le32(PCL_NEXT_INVALID);588 lynx->rcv_pcl->async_error_next = cpu_to_le32(PCL_NEXT_INVALID);589 590 lynx->rcv_pcl->buffer[0].control =591 cpu_to_le32(PCL_CMD_RCV | PCL_BIGENDIAN | 2044);592 lynx->rcv_pcl->buffer[0].pointer =593 cpu_to_le32(lynx->rcv_buffer_bus + 4);594 p = lynx->rcv_buffer_bus + 2048;595 end = lynx->rcv_buffer_bus + RCV_BUFFER_SIZE;596 for (i = 1; p < end; i++, p += 2048) {597 lynx->rcv_pcl->buffer[i].control =598 cpu_to_le32(PCL_CMD_RCV | PCL_BIGENDIAN | 2048);599 lynx->rcv_pcl->buffer[i].pointer = cpu_to_le32(p);600 }601 lynx->rcv_pcl->buffer[i - 1].control |= cpu_to_le32(PCL_LAST_BUFF);602 603 reg_set_bits(lynx, MISC_CONTROL, MISC_CONTROL_SWRESET);604 /* Fix buggy cards with autoboot pin not tied low: */605 reg_write(lynx, DMA0_CHAN_CTRL, 0);606 reg_write(lynx, DMA_GLOBAL_REGISTER, 0x00 << 24);607 608#if 0609 /* now, looking for PHY register set */610 if ((get_phy_reg(lynx, 2) & 0xe0) == 0xe0) {611 lynx->phyic.reg_1394a = 1;612 PRINT(KERN_INFO, lynx->id,613 "found 1394a conform PHY (using extended register set)");614 lynx->phyic.vendor = get_phy_vendorid(lynx);615 lynx->phyic.product = get_phy_productid(lynx);616 } else {617 lynx->phyic.reg_1394a = 0;618 PRINT(KERN_INFO, lynx->id, "found old 1394 PHY");619 }620#endif621 622 /* Setup the general receive FIFO max size. */623 reg_write(lynx, FIFO_SIZES, 255);624 625 reg_set_bits(lynx, PCI_INT_ENABLE, PCI_INT_DMA_ALL);626 627 reg_write(lynx, LINK_INT_ENABLE,628 LINK_INT_PHY_TIME_OUT | LINK_INT_PHY_REG_RCVD |629 LINK_INT_PHY_BUSRESET | LINK_INT_IT_STUCK |630 LINK_INT_AT_STUCK | LINK_INT_SNTRJ |631 LINK_INT_TC_ERR | LINK_INT_GRF_OVER_FLOW |632 LINK_INT_ITF_UNDER_FLOW | LINK_INT_ATF_UNDER_FLOW);633 634 /* Disable the L flag in self ID packets. */635 set_phy_reg(lynx, 4, 0);636 637 /* Put this baby into snoop mode */638 reg_set_bits(lynx, LINK_CONTROL, LINK_CONTROL_SNOOP_ENABLE);639 640 run_pcl(lynx, lynx->rcv_start_pcl_bus, 0);641 642 if (request_irq(dev->irq, irq_handler, IRQF_SHARED,643 driver_name, lynx)) {644 dev_err(&dev->dev,645 "Failed to allocate shared interrupt %d\n", dev->irq);646 ret = -EIO;647 goto fail_deallocate_buffers;648 }649 650 lynx->misc.parent = &dev->dev;651 lynx->misc.minor = MISC_DYNAMIC_MINOR;652 lynx->misc.name = "nosy";653 lynx->misc.fops = &nosy_ops;654 655 mutex_lock(&card_mutex);656 ret = misc_register(&lynx->misc);657 if (ret) {658 dev_err(&dev->dev, "Failed to register misc char device\n");659 mutex_unlock(&card_mutex);660 goto fail_free_irq;661 }662 list_add_tail(&lynx->link, &card_list);663 mutex_unlock(&card_mutex);664 665 dev_info(&dev->dev,666 "Initialized PCILynx IEEE1394 card, irq=%d\n", dev->irq);667 668 return 0;669 670fail_free_irq:671 reg_write(lynx, PCI_INT_ENABLE, 0);672 free_irq(lynx->pci_device->irq, lynx);673 674fail_deallocate_buffers:675 if (lynx->rcv_start_pcl)676 dma_free_coherent(&lynx->pci_device->dev, sizeof(struct pcl),677 lynx->rcv_start_pcl,678 lynx->rcv_start_pcl_bus);679 if (lynx->rcv_pcl)680 dma_free_coherent(&lynx->pci_device->dev, sizeof(struct pcl),681 lynx->rcv_pcl, lynx->rcv_pcl_bus);682 if (lynx->rcv_buffer)683 dma_free_coherent(&lynx->pci_device->dev, PAGE_SIZE,684 lynx->rcv_buffer, lynx->rcv_buffer_bus);685 iounmap(lynx->registers);686 687fail_deallocate_lynx:688 kfree(lynx);689 690fail_disable:691 pci_disable_device(dev);692 693 return ret;694}695 696static struct pci_device_id pci_table[] = {697 {698 .vendor = PCI_VENDOR_ID_TI,699 .device = PCI_DEVICE_ID_TI_PCILYNX,700 .subvendor = PCI_ANY_ID,701 .subdevice = PCI_ANY_ID,702 },703 { } /* Terminating entry */704};705 706MODULE_DEVICE_TABLE(pci, pci_table);707 708static struct pci_driver lynx_pci_driver = {709 .name = driver_name,710 .id_table = pci_table,711 .probe = add_card,712 .remove = remove_card,713};714 715module_pci_driver(lynx_pci_driver);716 717MODULE_AUTHOR("Kristian Hoegsberg");718MODULE_DESCRIPTION("Snoop mode driver for TI pcilynx 1394 controllers");719MODULE_LICENSE("GPL");720