rt2x00: do not pause queue unconditionally on error path
[linux-2.6/btrfs-unstable.git] / samples / vfio-mdev / mtty.c
blob09f255bdf3ace89b83b560b6d24a8ee1d136ee71
1 /*
2 * Mediated virtual PCI serial host device driver
4 * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
5 * Author: Neo Jia <cjia@nvidia.com>
6 * Kirti Wankhede <kwankhede@nvidia.com>
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
12 * Sample driver that creates mdev device that simulates serial port over PCI
13 * card.
17 #include <linux/init.h>
18 #include <linux/module.h>
19 #include <linux/device.h>
20 #include <linux/kernel.h>
21 #include <linux/fs.h>
22 #include <linux/poll.h>
23 #include <linux/slab.h>
24 #include <linux/cdev.h>
25 #include <linux/sched.h>
26 #include <linux/wait.h>
27 #include <linux/uuid.h>
28 #include <linux/vfio.h>
29 #include <linux/iommu.h>
30 #include <linux/sysfs.h>
31 #include <linux/ctype.h>
32 #include <linux/file.h>
33 #include <linux/mdev.h>
34 #include <linux/pci.h>
35 #include <linux/serial.h>
36 #include <uapi/linux/serial_reg.h>
37 #include <linux/eventfd.h>
39 * #defines
42 #define VERSION_STRING "0.1"
43 #define DRIVER_AUTHOR "NVIDIA Corporation"
45 #define MTTY_CLASS_NAME "mtty"
47 #define MTTY_NAME "mtty"
49 #define MTTY_STRING_LEN 16
51 #define MTTY_CONFIG_SPACE_SIZE 0xff
52 #define MTTY_IO_BAR_SIZE 0x8
53 #define MTTY_MMIO_BAR_SIZE 0x100000
55 #define STORE_LE16(addr, val) (*(u16 *)addr = val)
56 #define STORE_LE32(addr, val) (*(u32 *)addr = val)
58 #define MAX_FIFO_SIZE 16
60 #define CIRCULAR_BUF_INC_IDX(idx) (idx = (idx + 1) & (MAX_FIFO_SIZE - 1))
62 #define MTTY_VFIO_PCI_OFFSET_SHIFT 40
64 #define MTTY_VFIO_PCI_OFFSET_TO_INDEX(off) (off >> MTTY_VFIO_PCI_OFFSET_SHIFT)
65 #define MTTY_VFIO_PCI_INDEX_TO_OFFSET(index) \
66 ((u64)(index) << MTTY_VFIO_PCI_OFFSET_SHIFT)
67 #define MTTY_VFIO_PCI_OFFSET_MASK \
68 (((u64)(1) << MTTY_VFIO_PCI_OFFSET_SHIFT) - 1)
69 #define MAX_MTTYS 24
72 * Global Structures
75 struct mtty_dev {
76 dev_t vd_devt;
77 struct class *vd_class;
78 struct cdev vd_cdev;
79 struct idr vd_idr;
80 struct device dev;
81 } mtty_dev;
83 struct mdev_region_info {
84 u64 start;
85 u64 phys_start;
86 u32 size;
87 u64 vfio_offset;
90 #if defined(DEBUG_REGS)
91 const char *wr_reg[] = {
92 "TX",
93 "IER",
94 "FCR",
95 "LCR",
96 "MCR",
97 "LSR",
98 "MSR",
99 "SCR"
102 const char *rd_reg[] = {
103 "RX",
104 "IER",
105 "IIR",
106 "LCR",
107 "MCR",
108 "LSR",
109 "MSR",
110 "SCR"
112 #endif
114 /* loop back buffer */
115 struct rxtx {
116 u8 fifo[MAX_FIFO_SIZE];
117 u8 head, tail;
118 u8 count;
121 struct serial_port {
122 u8 uart_reg[8]; /* 8 registers */
123 struct rxtx rxtx; /* loop back buffer */
124 bool dlab;
125 bool overrun;
126 u16 divisor;
127 u8 fcr; /* FIFO control register */
128 u8 max_fifo_size;
129 u8 intr_trigger_level; /* interrupt trigger level */
132 /* State of each mdev device */
133 struct mdev_state {
134 int irq_fd;
135 struct eventfd_ctx *intx_evtfd;
136 struct eventfd_ctx *msi_evtfd;
137 int irq_index;
138 u8 *vconfig;
139 struct mutex ops_lock;
140 struct mdev_device *mdev;
141 struct mdev_region_info region_info[VFIO_PCI_NUM_REGIONS];
142 u32 bar_mask[VFIO_PCI_NUM_REGIONS];
143 struct list_head next;
144 struct serial_port s[2];
145 struct mutex rxtx_lock;
146 struct vfio_device_info dev_info;
147 int nr_ports;
150 struct mutex mdev_list_lock;
151 struct list_head mdev_devices_list;
153 static const struct file_operations vd_fops = {
154 .owner = THIS_MODULE,
157 /* function prototypes */
159 static int mtty_trigger_interrupt(uuid_le uuid);
161 /* Helper functions */
162 static struct mdev_state *find_mdev_state_by_uuid(uuid_le uuid)
164 struct mdev_state *mds;
166 list_for_each_entry(mds, &mdev_devices_list, next) {
167 if (uuid_le_cmp(mdev_uuid(mds->mdev), uuid) == 0)
168 return mds;
171 return NULL;
174 void dump_buffer(char *buf, uint32_t count)
176 #if defined(DEBUG)
177 int i;
179 pr_info("Buffer:\n");
180 for (i = 0; i < count; i++) {
181 pr_info("%2x ", *(buf + i));
182 if ((i + 1) % 16 == 0)
183 pr_info("\n");
185 #endif
188 static void mtty_create_config_space(struct mdev_state *mdev_state)
190 /* PCI dev ID */
191 STORE_LE32((u32 *) &mdev_state->vconfig[0x0], 0x32534348);
193 /* Control: I/O+, Mem-, BusMaster- */
194 STORE_LE16((u16 *) &mdev_state->vconfig[0x4], 0x0001);
196 /* Status: capabilities list absent */
197 STORE_LE16((u16 *) &mdev_state->vconfig[0x6], 0x0200);
199 /* Rev ID */
200 mdev_state->vconfig[0x8] = 0x10;
202 /* programming interface class : 16550-compatible serial controller */
203 mdev_state->vconfig[0x9] = 0x02;
205 /* Sub class : 00 */
206 mdev_state->vconfig[0xa] = 0x00;
208 /* Base class : Simple Communication controllers */
209 mdev_state->vconfig[0xb] = 0x07;
211 /* base address registers */
212 /* BAR0: IO space */
213 STORE_LE32((u32 *) &mdev_state->vconfig[0x10], 0x000001);
214 mdev_state->bar_mask[0] = ~(MTTY_IO_BAR_SIZE) + 1;
216 if (mdev_state->nr_ports == 2) {
217 /* BAR1: IO space */
218 STORE_LE32((u32 *) &mdev_state->vconfig[0x14], 0x000001);
219 mdev_state->bar_mask[1] = ~(MTTY_IO_BAR_SIZE) + 1;
222 /* Subsystem ID */
223 STORE_LE32((u32 *) &mdev_state->vconfig[0x2c], 0x32534348);
225 mdev_state->vconfig[0x34] = 0x00; /* Cap Ptr */
226 mdev_state->vconfig[0x3d] = 0x01; /* interrupt pin (INTA#) */
228 /* Vendor specific data */
229 mdev_state->vconfig[0x40] = 0x23;
230 mdev_state->vconfig[0x43] = 0x80;
231 mdev_state->vconfig[0x44] = 0x23;
232 mdev_state->vconfig[0x48] = 0x23;
233 mdev_state->vconfig[0x4c] = 0x23;
235 mdev_state->vconfig[0x60] = 0x50;
236 mdev_state->vconfig[0x61] = 0x43;
237 mdev_state->vconfig[0x62] = 0x49;
238 mdev_state->vconfig[0x63] = 0x20;
239 mdev_state->vconfig[0x64] = 0x53;
240 mdev_state->vconfig[0x65] = 0x65;
241 mdev_state->vconfig[0x66] = 0x72;
242 mdev_state->vconfig[0x67] = 0x69;
243 mdev_state->vconfig[0x68] = 0x61;
244 mdev_state->vconfig[0x69] = 0x6c;
245 mdev_state->vconfig[0x6a] = 0x2f;
246 mdev_state->vconfig[0x6b] = 0x55;
247 mdev_state->vconfig[0x6c] = 0x41;
248 mdev_state->vconfig[0x6d] = 0x52;
249 mdev_state->vconfig[0x6e] = 0x54;
252 static void handle_pci_cfg_write(struct mdev_state *mdev_state, u16 offset,
253 char *buf, u32 count)
255 u32 cfg_addr, bar_mask, bar_index = 0;
257 switch (offset) {
258 case 0x04: /* device control */
259 case 0x06: /* device status */
260 /* do nothing */
261 break;
262 case 0x3c: /* interrupt line */
263 mdev_state->vconfig[0x3c] = buf[0];
264 break;
265 case 0x3d:
267 * Interrupt Pin is hardwired to INTA.
268 * This field is write protected by hardware
270 break;
271 case 0x10: /* BAR0 */
272 case 0x14: /* BAR1 */
273 if (offset == 0x10)
274 bar_index = 0;
275 else if (offset == 0x14)
276 bar_index = 1;
278 if ((mdev_state->nr_ports == 1) && (bar_index == 1)) {
279 STORE_LE32(&mdev_state->vconfig[offset], 0);
280 break;
283 cfg_addr = *(u32 *)buf;
284 pr_info("BAR%d addr 0x%x\n", bar_index, cfg_addr);
286 if (cfg_addr == 0xffffffff) {
287 bar_mask = mdev_state->bar_mask[bar_index];
288 cfg_addr = (cfg_addr & bar_mask);
291 cfg_addr |= (mdev_state->vconfig[offset] & 0x3ul);
292 STORE_LE32(&mdev_state->vconfig[offset], cfg_addr);
293 break;
294 case 0x18: /* BAR2 */
295 case 0x1c: /* BAR3 */
296 case 0x20: /* BAR4 */
297 STORE_LE32(&mdev_state->vconfig[offset], 0);
298 break;
299 default:
300 pr_info("PCI config write @0x%x of %d bytes not handled\n",
301 offset, count);
302 break;
306 static void handle_bar_write(unsigned int index, struct mdev_state *mdev_state,
307 u16 offset, char *buf, u32 count)
309 u8 data = *buf;
311 /* Handle data written by guest */
312 switch (offset) {
313 case UART_TX:
314 /* if DLAB set, data is LSB of divisor */
315 if (mdev_state->s[index].dlab) {
316 mdev_state->s[index].divisor |= data;
317 break;
320 mutex_lock(&mdev_state->rxtx_lock);
322 /* save in TX buffer */
323 if (mdev_state->s[index].rxtx.count <
324 mdev_state->s[index].max_fifo_size) {
325 mdev_state->s[index].rxtx.fifo[
326 mdev_state->s[index].rxtx.head] = data;
327 mdev_state->s[index].rxtx.count++;
328 CIRCULAR_BUF_INC_IDX(mdev_state->s[index].rxtx.head);
329 mdev_state->s[index].overrun = false;
332 * Trigger interrupt if receive data interrupt is
333 * enabled and fifo reached trigger level
335 if ((mdev_state->s[index].uart_reg[UART_IER] &
336 UART_IER_RDI) &&
337 (mdev_state->s[index].rxtx.count ==
338 mdev_state->s[index].intr_trigger_level)) {
339 /* trigger interrupt */
340 #if defined(DEBUG_INTR)
341 pr_err("Serial port %d: Fifo level trigger\n",
342 index);
343 #endif
344 mtty_trigger_interrupt(
345 mdev_uuid(mdev_state->mdev));
347 } else {
348 #if defined(DEBUG_INTR)
349 pr_err("Serial port %d: Buffer Overflow\n", index);
350 #endif
351 mdev_state->s[index].overrun = true;
354 * Trigger interrupt if receiver line status interrupt
355 * is enabled
357 if (mdev_state->s[index].uart_reg[UART_IER] &
358 UART_IER_RLSI)
359 mtty_trigger_interrupt(
360 mdev_uuid(mdev_state->mdev));
362 mutex_unlock(&mdev_state->rxtx_lock);
363 break;
365 case UART_IER:
366 /* if DLAB set, data is MSB of divisor */
367 if (mdev_state->s[index].dlab)
368 mdev_state->s[index].divisor |= (u16)data << 8;
369 else {
370 mdev_state->s[index].uart_reg[offset] = data;
371 mutex_lock(&mdev_state->rxtx_lock);
372 if ((data & UART_IER_THRI) &&
373 (mdev_state->s[index].rxtx.head ==
374 mdev_state->s[index].rxtx.tail)) {
375 #if defined(DEBUG_INTR)
376 pr_err("Serial port %d: IER_THRI write\n",
377 index);
378 #endif
379 mtty_trigger_interrupt(
380 mdev_uuid(mdev_state->mdev));
383 mutex_unlock(&mdev_state->rxtx_lock);
386 break;
388 case UART_FCR:
389 mdev_state->s[index].fcr = data;
391 mutex_lock(&mdev_state->rxtx_lock);
392 if (data & (UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT)) {
393 /* clear loop back FIFO */
394 mdev_state->s[index].rxtx.count = 0;
395 mdev_state->s[index].rxtx.head = 0;
396 mdev_state->s[index].rxtx.tail = 0;
398 mutex_unlock(&mdev_state->rxtx_lock);
400 switch (data & UART_FCR_TRIGGER_MASK) {
401 case UART_FCR_TRIGGER_1:
402 mdev_state->s[index].intr_trigger_level = 1;
403 break;
405 case UART_FCR_TRIGGER_4:
406 mdev_state->s[index].intr_trigger_level = 4;
407 break;
409 case UART_FCR_TRIGGER_8:
410 mdev_state->s[index].intr_trigger_level = 8;
411 break;
413 case UART_FCR_TRIGGER_14:
414 mdev_state->s[index].intr_trigger_level = 14;
415 break;
419 * Set trigger level to 1 otherwise or implement timer with
420 * timeout of 4 characters and on expiring that timer set
421 * Recevice data timeout in IIR register
423 mdev_state->s[index].intr_trigger_level = 1;
424 if (data & UART_FCR_ENABLE_FIFO)
425 mdev_state->s[index].max_fifo_size = MAX_FIFO_SIZE;
426 else {
427 mdev_state->s[index].max_fifo_size = 1;
428 mdev_state->s[index].intr_trigger_level = 1;
431 break;
433 case UART_LCR:
434 if (data & UART_LCR_DLAB) {
435 mdev_state->s[index].dlab = true;
436 mdev_state->s[index].divisor = 0;
437 } else
438 mdev_state->s[index].dlab = false;
440 mdev_state->s[index].uart_reg[offset] = data;
441 break;
443 case UART_MCR:
444 mdev_state->s[index].uart_reg[offset] = data;
446 if ((mdev_state->s[index].uart_reg[UART_IER] & UART_IER_MSI) &&
447 (data & UART_MCR_OUT2)) {
448 #if defined(DEBUG_INTR)
449 pr_err("Serial port %d: MCR_OUT2 write\n", index);
450 #endif
451 mtty_trigger_interrupt(mdev_uuid(mdev_state->mdev));
454 if ((mdev_state->s[index].uart_reg[UART_IER] & UART_IER_MSI) &&
455 (data & (UART_MCR_RTS | UART_MCR_DTR))) {
456 #if defined(DEBUG_INTR)
457 pr_err("Serial port %d: MCR RTS/DTR write\n", index);
458 #endif
459 mtty_trigger_interrupt(mdev_uuid(mdev_state->mdev));
461 break;
463 case UART_LSR:
464 case UART_MSR:
465 /* do nothing */
466 break;
468 case UART_SCR:
469 mdev_state->s[index].uart_reg[offset] = data;
470 break;
472 default:
473 break;
477 static void handle_bar_read(unsigned int index, struct mdev_state *mdev_state,
478 u16 offset, char *buf, u32 count)
480 /* Handle read requests by guest */
481 switch (offset) {
482 case UART_RX:
483 /* if DLAB set, data is LSB of divisor */
484 if (mdev_state->s[index].dlab) {
485 *buf = (u8)mdev_state->s[index].divisor;
486 break;
489 mutex_lock(&mdev_state->rxtx_lock);
490 /* return data in tx buffer */
491 if (mdev_state->s[index].rxtx.head !=
492 mdev_state->s[index].rxtx.tail) {
493 *buf = mdev_state->s[index].rxtx.fifo[
494 mdev_state->s[index].rxtx.tail];
495 mdev_state->s[index].rxtx.count--;
496 CIRCULAR_BUF_INC_IDX(mdev_state->s[index].rxtx.tail);
499 if (mdev_state->s[index].rxtx.head ==
500 mdev_state->s[index].rxtx.tail) {
502 * Trigger interrupt if tx buffer empty interrupt is
503 * enabled and fifo is empty
505 #if defined(DEBUG_INTR)
506 pr_err("Serial port %d: Buffer Empty\n", index);
507 #endif
508 if (mdev_state->s[index].uart_reg[UART_IER] &
509 UART_IER_THRI)
510 mtty_trigger_interrupt(
511 mdev_uuid(mdev_state->mdev));
513 mutex_unlock(&mdev_state->rxtx_lock);
515 break;
517 case UART_IER:
518 if (mdev_state->s[index].dlab) {
519 *buf = (u8)(mdev_state->s[index].divisor >> 8);
520 break;
522 *buf = mdev_state->s[index].uart_reg[offset] & 0x0f;
523 break;
525 case UART_IIR:
527 u8 ier = mdev_state->s[index].uart_reg[UART_IER];
528 *buf = 0;
530 mutex_lock(&mdev_state->rxtx_lock);
531 /* Interrupt priority 1: Parity, overrun, framing or break */
532 if ((ier & UART_IER_RLSI) && mdev_state->s[index].overrun)
533 *buf |= UART_IIR_RLSI;
535 /* Interrupt priority 2: Fifo trigger level reached */
536 if ((ier & UART_IER_RDI) &&
537 (mdev_state->s[index].rxtx.count ==
538 mdev_state->s[index].intr_trigger_level))
539 *buf |= UART_IIR_RDI;
541 /* Interrupt priotiry 3: transmitter holding register empty */
542 if ((ier & UART_IER_THRI) &&
543 (mdev_state->s[index].rxtx.head ==
544 mdev_state->s[index].rxtx.tail))
545 *buf |= UART_IIR_THRI;
547 /* Interrupt priotiry 4: Modem status: CTS, DSR, RI or DCD */
548 if ((ier & UART_IER_MSI) &&
549 (mdev_state->s[index].uart_reg[UART_MCR] &
550 (UART_MCR_RTS | UART_MCR_DTR)))
551 *buf |= UART_IIR_MSI;
553 /* bit0: 0=> interrupt pending, 1=> no interrupt is pending */
554 if (*buf == 0)
555 *buf = UART_IIR_NO_INT;
557 /* set bit 6 & 7 to be 16550 compatible */
558 *buf |= 0xC0;
559 mutex_unlock(&mdev_state->rxtx_lock);
561 break;
563 case UART_LCR:
564 case UART_MCR:
565 *buf = mdev_state->s[index].uart_reg[offset];
566 break;
568 case UART_LSR:
570 u8 lsr = 0;
572 mutex_lock(&mdev_state->rxtx_lock);
573 /* atleast one char in FIFO */
574 if (mdev_state->s[index].rxtx.head !=
575 mdev_state->s[index].rxtx.tail)
576 lsr |= UART_LSR_DR;
578 /* if FIFO overrun */
579 if (mdev_state->s[index].overrun)
580 lsr |= UART_LSR_OE;
582 /* transmit FIFO empty and tramsitter empty */
583 if (mdev_state->s[index].rxtx.head ==
584 mdev_state->s[index].rxtx.tail)
585 lsr |= UART_LSR_TEMT | UART_LSR_THRE;
587 mutex_unlock(&mdev_state->rxtx_lock);
588 *buf = lsr;
589 break;
591 case UART_MSR:
592 *buf = UART_MSR_DSR | UART_MSR_DDSR | UART_MSR_DCD;
594 mutex_lock(&mdev_state->rxtx_lock);
595 /* if AFE is 1 and FIFO have space, set CTS bit */
596 if (mdev_state->s[index].uart_reg[UART_MCR] &
597 UART_MCR_AFE) {
598 if (mdev_state->s[index].rxtx.count <
599 mdev_state->s[index].max_fifo_size)
600 *buf |= UART_MSR_CTS | UART_MSR_DCTS;
601 } else
602 *buf |= UART_MSR_CTS | UART_MSR_DCTS;
603 mutex_unlock(&mdev_state->rxtx_lock);
605 break;
607 case UART_SCR:
608 *buf = mdev_state->s[index].uart_reg[offset];
609 break;
611 default:
612 break;
616 static void mdev_read_base(struct mdev_state *mdev_state)
618 int index, pos;
619 u32 start_lo, start_hi;
620 u32 mem_type;
622 pos = PCI_BASE_ADDRESS_0;
624 for (index = 0; index <= VFIO_PCI_BAR5_REGION_INDEX; index++) {
626 if (!mdev_state->region_info[index].size)
627 continue;
629 start_lo = (*(u32 *)(mdev_state->vconfig + pos)) &
630 PCI_BASE_ADDRESS_MEM_MASK;
631 mem_type = (*(u32 *)(mdev_state->vconfig + pos)) &
632 PCI_BASE_ADDRESS_MEM_TYPE_MASK;
634 switch (mem_type) {
635 case PCI_BASE_ADDRESS_MEM_TYPE_64:
636 start_hi = (*(u32 *)(mdev_state->vconfig + pos + 4));
637 pos += 4;
638 break;
639 case PCI_BASE_ADDRESS_MEM_TYPE_32:
640 case PCI_BASE_ADDRESS_MEM_TYPE_1M:
641 /* 1M mem BAR treated as 32-bit BAR */
642 default:
643 /* mem unknown type treated as 32-bit BAR */
644 start_hi = 0;
645 break;
647 pos += 4;
648 mdev_state->region_info[index].start = ((u64)start_hi << 32) |
649 start_lo;
653 static ssize_t mdev_access(struct mdev_device *mdev, char *buf, size_t count,
654 loff_t pos, bool is_write)
656 struct mdev_state *mdev_state;
657 unsigned int index;
658 loff_t offset;
659 int ret = 0;
661 if (!mdev || !buf)
662 return -EINVAL;
664 mdev_state = mdev_get_drvdata(mdev);
665 if (!mdev_state) {
666 pr_err("%s mdev_state not found\n", __func__);
667 return -EINVAL;
670 mutex_lock(&mdev_state->ops_lock);
672 index = MTTY_VFIO_PCI_OFFSET_TO_INDEX(pos);
673 offset = pos & MTTY_VFIO_PCI_OFFSET_MASK;
674 switch (index) {
675 case VFIO_PCI_CONFIG_REGION_INDEX:
677 #if defined(DEBUG)
678 pr_info("%s: PCI config space %s at offset 0x%llx\n",
679 __func__, is_write ? "write" : "read", offset);
680 #endif
681 if (is_write) {
682 dump_buffer(buf, count);
683 handle_pci_cfg_write(mdev_state, offset, buf, count);
684 } else {
685 memcpy(buf, (mdev_state->vconfig + offset), count);
686 dump_buffer(buf, count);
689 break;
691 case VFIO_PCI_BAR0_REGION_INDEX ... VFIO_PCI_BAR5_REGION_INDEX:
692 if (!mdev_state->region_info[index].start)
693 mdev_read_base(mdev_state);
695 if (is_write) {
696 dump_buffer(buf, count);
698 #if defined(DEBUG_REGS)
699 pr_info("%s: BAR%d WR @0x%llx %s val:0x%02x dlab:%d\n",
700 __func__, index, offset, wr_reg[offset],
701 (u8)*buf, mdev_state->s[index].dlab);
702 #endif
703 handle_bar_write(index, mdev_state, offset, buf, count);
704 } else {
705 handle_bar_read(index, mdev_state, offset, buf, count);
706 dump_buffer(buf, count);
708 #if defined(DEBUG_REGS)
709 pr_info("%s: BAR%d RD @0x%llx %s val:0x%02x dlab:%d\n",
710 __func__, index, offset, rd_reg[offset],
711 (u8)*buf, mdev_state->s[index].dlab);
712 #endif
714 break;
716 default:
717 ret = -1;
718 goto accessfailed;
721 ret = count;
724 accessfailed:
725 mutex_unlock(&mdev_state->ops_lock);
727 return ret;
730 int mtty_create(struct kobject *kobj, struct mdev_device *mdev)
732 struct mdev_state *mdev_state;
733 char name[MTTY_STRING_LEN];
734 int nr_ports = 0, i;
736 if (!mdev)
737 return -EINVAL;
739 for (i = 0; i < 2; i++) {
740 snprintf(name, MTTY_STRING_LEN, "%s-%d",
741 dev_driver_string(mdev_parent_dev(mdev)), i + 1);
742 if (!strcmp(kobj->name, name)) {
743 nr_ports = i + 1;
744 break;
748 if (!nr_ports)
749 return -EINVAL;
751 mdev_state = kzalloc(sizeof(struct mdev_state), GFP_KERNEL);
752 if (mdev_state == NULL)
753 return -ENOMEM;
755 mdev_state->nr_ports = nr_ports;
756 mdev_state->irq_index = -1;
757 mdev_state->s[0].max_fifo_size = MAX_FIFO_SIZE;
758 mdev_state->s[1].max_fifo_size = MAX_FIFO_SIZE;
759 mutex_init(&mdev_state->rxtx_lock);
760 mdev_state->vconfig = kzalloc(MTTY_CONFIG_SPACE_SIZE, GFP_KERNEL);
762 if (mdev_state->vconfig == NULL) {
763 kfree(mdev_state);
764 return -ENOMEM;
767 mutex_init(&mdev_state->ops_lock);
768 mdev_state->mdev = mdev;
769 mdev_set_drvdata(mdev, mdev_state);
771 mtty_create_config_space(mdev_state);
773 mutex_lock(&mdev_list_lock);
774 list_add(&mdev_state->next, &mdev_devices_list);
775 mutex_unlock(&mdev_list_lock);
777 return 0;
780 int mtty_remove(struct mdev_device *mdev)
782 struct mdev_state *mds, *tmp_mds;
783 struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
784 int ret = -EINVAL;
786 mutex_lock(&mdev_list_lock);
787 list_for_each_entry_safe(mds, tmp_mds, &mdev_devices_list, next) {
788 if (mdev_state == mds) {
789 list_del(&mdev_state->next);
790 mdev_set_drvdata(mdev, NULL);
791 kfree(mdev_state->vconfig);
792 kfree(mdev_state);
793 ret = 0;
794 break;
797 mutex_unlock(&mdev_list_lock);
799 return ret;
802 int mtty_reset(struct mdev_device *mdev)
804 struct mdev_state *mdev_state;
806 if (!mdev)
807 return -EINVAL;
809 mdev_state = mdev_get_drvdata(mdev);
810 if (!mdev_state)
811 return -EINVAL;
813 pr_info("%s: called\n", __func__);
815 return 0;
818 ssize_t mtty_read(struct mdev_device *mdev, char __user *buf, size_t count,
819 loff_t *ppos)
821 unsigned int done = 0;
822 int ret;
824 while (count) {
825 size_t filled;
827 if (count >= 4 && !(*ppos % 4)) {
828 u32 val;
830 ret = mdev_access(mdev, (char *)&val, sizeof(val),
831 *ppos, false);
832 if (ret <= 0)
833 goto read_err;
835 if (copy_to_user(buf, &val, sizeof(val)))
836 goto read_err;
838 filled = 4;
839 } else if (count >= 2 && !(*ppos % 2)) {
840 u16 val;
842 ret = mdev_access(mdev, (char *)&val, sizeof(val),
843 *ppos, false);
844 if (ret <= 0)
845 goto read_err;
847 if (copy_to_user(buf, &val, sizeof(val)))
848 goto read_err;
850 filled = 2;
851 } else {
852 u8 val;
854 ret = mdev_access(mdev, (char *)&val, sizeof(val),
855 *ppos, false);
856 if (ret <= 0)
857 goto read_err;
859 if (copy_to_user(buf, &val, sizeof(val)))
860 goto read_err;
862 filled = 1;
865 count -= filled;
866 done += filled;
867 *ppos += filled;
868 buf += filled;
871 return done;
873 read_err:
874 return -EFAULT;
877 ssize_t mtty_write(struct mdev_device *mdev, const char __user *buf,
878 size_t count, loff_t *ppos)
880 unsigned int done = 0;
881 int ret;
883 while (count) {
884 size_t filled;
886 if (count >= 4 && !(*ppos % 4)) {
887 u32 val;
889 if (copy_from_user(&val, buf, sizeof(val)))
890 goto write_err;
892 ret = mdev_access(mdev, (char *)&val, sizeof(val),
893 *ppos, true);
894 if (ret <= 0)
895 goto write_err;
897 filled = 4;
898 } else if (count >= 2 && !(*ppos % 2)) {
899 u16 val;
901 if (copy_from_user(&val, buf, sizeof(val)))
902 goto write_err;
904 ret = mdev_access(mdev, (char *)&val, sizeof(val),
905 *ppos, true);
906 if (ret <= 0)
907 goto write_err;
909 filled = 2;
910 } else {
911 u8 val;
913 if (copy_from_user(&val, buf, sizeof(val)))
914 goto write_err;
916 ret = mdev_access(mdev, (char *)&val, sizeof(val),
917 *ppos, true);
918 if (ret <= 0)
919 goto write_err;
921 filled = 1;
923 count -= filled;
924 done += filled;
925 *ppos += filled;
926 buf += filled;
929 return done;
930 write_err:
931 return -EFAULT;
934 static int mtty_set_irqs(struct mdev_device *mdev, uint32_t flags,
935 unsigned int index, unsigned int start,
936 unsigned int count, void *data)
938 int ret = 0;
939 struct mdev_state *mdev_state;
941 if (!mdev)
942 return -EINVAL;
944 mdev_state = mdev_get_drvdata(mdev);
945 if (!mdev_state)
946 return -EINVAL;
948 mutex_lock(&mdev_state->ops_lock);
949 switch (index) {
950 case VFIO_PCI_INTX_IRQ_INDEX:
951 switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
952 case VFIO_IRQ_SET_ACTION_MASK:
953 case VFIO_IRQ_SET_ACTION_UNMASK:
954 break;
955 case VFIO_IRQ_SET_ACTION_TRIGGER:
957 if (flags & VFIO_IRQ_SET_DATA_NONE) {
958 pr_info("%s: disable INTx\n", __func__);
959 if (mdev_state->intx_evtfd)
960 eventfd_ctx_put(mdev_state->intx_evtfd);
961 break;
964 if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
965 int fd = *(int *)data;
967 if (fd > 0) {
968 struct eventfd_ctx *evt;
970 evt = eventfd_ctx_fdget(fd);
971 if (IS_ERR(evt)) {
972 ret = PTR_ERR(evt);
973 break;
975 mdev_state->intx_evtfd = evt;
976 mdev_state->irq_fd = fd;
977 mdev_state->irq_index = index;
978 break;
981 break;
984 break;
985 case VFIO_PCI_MSI_IRQ_INDEX:
986 switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
987 case VFIO_IRQ_SET_ACTION_MASK:
988 case VFIO_IRQ_SET_ACTION_UNMASK:
989 break;
990 case VFIO_IRQ_SET_ACTION_TRIGGER:
991 if (flags & VFIO_IRQ_SET_DATA_NONE) {
992 if (mdev_state->msi_evtfd)
993 eventfd_ctx_put(mdev_state->msi_evtfd);
994 pr_info("%s: disable MSI\n", __func__);
995 mdev_state->irq_index = VFIO_PCI_INTX_IRQ_INDEX;
996 break;
998 if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
999 int fd = *(int *)data;
1000 struct eventfd_ctx *evt;
1002 if (fd <= 0)
1003 break;
1005 if (mdev_state->msi_evtfd)
1006 break;
1008 evt = eventfd_ctx_fdget(fd);
1009 if (IS_ERR(evt)) {
1010 ret = PTR_ERR(evt);
1011 break;
1013 mdev_state->msi_evtfd = evt;
1014 mdev_state->irq_fd = fd;
1015 mdev_state->irq_index = index;
1017 break;
1019 break;
1020 case VFIO_PCI_MSIX_IRQ_INDEX:
1021 pr_info("%s: MSIX_IRQ\n", __func__);
1022 break;
1023 case VFIO_PCI_ERR_IRQ_INDEX:
1024 pr_info("%s: ERR_IRQ\n", __func__);
1025 break;
1026 case VFIO_PCI_REQ_IRQ_INDEX:
1027 pr_info("%s: REQ_IRQ\n", __func__);
1028 break;
1031 mutex_unlock(&mdev_state->ops_lock);
1032 return ret;
1035 static int mtty_trigger_interrupt(uuid_le uuid)
1037 int ret = -1;
1038 struct mdev_state *mdev_state;
1040 mdev_state = find_mdev_state_by_uuid(uuid);
1042 if (!mdev_state) {
1043 pr_info("%s: mdev not found\n", __func__);
1044 return -EINVAL;
1047 if ((mdev_state->irq_index == VFIO_PCI_MSI_IRQ_INDEX) &&
1048 (!mdev_state->msi_evtfd))
1049 return -EINVAL;
1050 else if ((mdev_state->irq_index == VFIO_PCI_INTX_IRQ_INDEX) &&
1051 (!mdev_state->intx_evtfd)) {
1052 pr_info("%s: Intr eventfd not found\n", __func__);
1053 return -EINVAL;
1056 if (mdev_state->irq_index == VFIO_PCI_MSI_IRQ_INDEX)
1057 ret = eventfd_signal(mdev_state->msi_evtfd, 1);
1058 else
1059 ret = eventfd_signal(mdev_state->intx_evtfd, 1);
1061 #if defined(DEBUG_INTR)
1062 pr_info("Intx triggered\n");
1063 #endif
1064 if (ret != 1)
1065 pr_err("%s: eventfd signal failed (%d)\n", __func__, ret);
1067 return ret;
1070 int mtty_get_region_info(struct mdev_device *mdev,
1071 struct vfio_region_info *region_info,
1072 u16 *cap_type_id, void **cap_type)
1074 unsigned int size = 0;
1075 struct mdev_state *mdev_state;
1076 u32 bar_index;
1078 if (!mdev)
1079 return -EINVAL;
1081 mdev_state = mdev_get_drvdata(mdev);
1082 if (!mdev_state)
1083 return -EINVAL;
1085 bar_index = region_info->index;
1086 if (bar_index >= VFIO_PCI_NUM_REGIONS)
1087 return -EINVAL;
1089 mutex_lock(&mdev_state->ops_lock);
1091 switch (bar_index) {
1092 case VFIO_PCI_CONFIG_REGION_INDEX:
1093 size = MTTY_CONFIG_SPACE_SIZE;
1094 break;
1095 case VFIO_PCI_BAR0_REGION_INDEX:
1096 size = MTTY_IO_BAR_SIZE;
1097 break;
1098 case VFIO_PCI_BAR1_REGION_INDEX:
1099 if (mdev_state->nr_ports == 2)
1100 size = MTTY_IO_BAR_SIZE;
1101 break;
1102 default:
1103 size = 0;
1104 break;
1107 mdev_state->region_info[bar_index].size = size;
1108 mdev_state->region_info[bar_index].vfio_offset =
1109 MTTY_VFIO_PCI_INDEX_TO_OFFSET(bar_index);
1111 region_info->size = size;
1112 region_info->offset = MTTY_VFIO_PCI_INDEX_TO_OFFSET(bar_index);
1113 region_info->flags = VFIO_REGION_INFO_FLAG_READ |
1114 VFIO_REGION_INFO_FLAG_WRITE;
1115 mutex_unlock(&mdev_state->ops_lock);
1116 return 0;
1119 int mtty_get_irq_info(struct mdev_device *mdev, struct vfio_irq_info *irq_info)
1121 switch (irq_info->index) {
1122 case VFIO_PCI_INTX_IRQ_INDEX:
1123 case VFIO_PCI_MSI_IRQ_INDEX:
1124 case VFIO_PCI_REQ_IRQ_INDEX:
1125 break;
1127 default:
1128 return -EINVAL;
1131 irq_info->flags = VFIO_IRQ_INFO_EVENTFD;
1132 irq_info->count = 1;
1134 if (irq_info->index == VFIO_PCI_INTX_IRQ_INDEX)
1135 irq_info->flags |= (VFIO_IRQ_INFO_MASKABLE |
1136 VFIO_IRQ_INFO_AUTOMASKED);
1137 else
1138 irq_info->flags |= VFIO_IRQ_INFO_NORESIZE;
1140 return 0;
1143 int mtty_get_device_info(struct mdev_device *mdev,
1144 struct vfio_device_info *dev_info)
1146 dev_info->flags = VFIO_DEVICE_FLAGS_PCI;
1147 dev_info->num_regions = VFIO_PCI_NUM_REGIONS;
1148 dev_info->num_irqs = VFIO_PCI_NUM_IRQS;
1150 return 0;
1153 static long mtty_ioctl(struct mdev_device *mdev, unsigned int cmd,
1154 unsigned long arg)
1156 int ret = 0;
1157 unsigned long minsz;
1158 struct mdev_state *mdev_state;
1160 if (!mdev)
1161 return -EINVAL;
1163 mdev_state = mdev_get_drvdata(mdev);
1164 if (!mdev_state)
1165 return -ENODEV;
1167 switch (cmd) {
1168 case VFIO_DEVICE_GET_INFO:
1170 struct vfio_device_info info;
1172 minsz = offsetofend(struct vfio_device_info, num_irqs);
1174 if (copy_from_user(&info, (void __user *)arg, minsz))
1175 return -EFAULT;
1177 if (info.argsz < minsz)
1178 return -EINVAL;
1180 ret = mtty_get_device_info(mdev, &info);
1181 if (ret)
1182 return ret;
1184 memcpy(&mdev_state->dev_info, &info, sizeof(info));
1186 if (copy_to_user((void __user *)arg, &info, minsz))
1187 return -EFAULT;
1189 return 0;
1191 case VFIO_DEVICE_GET_REGION_INFO:
1193 struct vfio_region_info info;
1194 u16 cap_type_id = 0;
1195 void *cap_type = NULL;
1197 minsz = offsetofend(struct vfio_region_info, offset);
1199 if (copy_from_user(&info, (void __user *)arg, minsz))
1200 return -EFAULT;
1202 if (info.argsz < minsz)
1203 return -EINVAL;
1205 ret = mtty_get_region_info(mdev, &info, &cap_type_id,
1206 &cap_type);
1207 if (ret)
1208 return ret;
1210 if (copy_to_user((void __user *)arg, &info, minsz))
1211 return -EFAULT;
1213 return 0;
1216 case VFIO_DEVICE_GET_IRQ_INFO:
1218 struct vfio_irq_info info;
1220 minsz = offsetofend(struct vfio_irq_info, count);
1222 if (copy_from_user(&info, (void __user *)arg, minsz))
1223 return -EFAULT;
1225 if ((info.argsz < minsz) ||
1226 (info.index >= mdev_state->dev_info.num_irqs))
1227 return -EINVAL;
1229 ret = mtty_get_irq_info(mdev, &info);
1230 if (ret)
1231 return ret;
1233 if (copy_to_user((void __user *)arg, &info, minsz))
1234 return -EFAULT;
1236 return 0;
1238 case VFIO_DEVICE_SET_IRQS:
1240 struct vfio_irq_set hdr;
1241 u8 *data = NULL, *ptr = NULL;
1242 size_t data_size = 0;
1244 minsz = offsetofend(struct vfio_irq_set, count);
1246 if (copy_from_user(&hdr, (void __user *)arg, minsz))
1247 return -EFAULT;
1249 ret = vfio_set_irqs_validate_and_prepare(&hdr,
1250 mdev_state->dev_info.num_irqs,
1251 VFIO_PCI_NUM_IRQS,
1252 &data_size);
1253 if (ret)
1254 return ret;
1256 if (data_size) {
1257 ptr = data = memdup_user((void __user *)(arg + minsz),
1258 data_size);
1259 if (IS_ERR(data))
1260 return PTR_ERR(data);
1263 ret = mtty_set_irqs(mdev, hdr.flags, hdr.index, hdr.start,
1264 hdr.count, data);
1266 kfree(ptr);
1267 return ret;
1269 case VFIO_DEVICE_RESET:
1270 return mtty_reset(mdev);
1272 return -ENOTTY;
1275 int mtty_open(struct mdev_device *mdev)
1277 pr_info("%s\n", __func__);
1278 return 0;
1281 void mtty_close(struct mdev_device *mdev)
1283 pr_info("%s\n", __func__);
1286 static ssize_t
1287 sample_mtty_dev_show(struct device *dev, struct device_attribute *attr,
1288 char *buf)
1290 return sprintf(buf, "This is phy device\n");
1293 static DEVICE_ATTR_RO(sample_mtty_dev);
1295 static struct attribute *mtty_dev_attrs[] = {
1296 &dev_attr_sample_mtty_dev.attr,
1297 NULL,
1300 static const struct attribute_group mtty_dev_group = {
1301 .name = "mtty_dev",
1302 .attrs = mtty_dev_attrs,
1305 const struct attribute_group *mtty_dev_groups[] = {
1306 &mtty_dev_group,
1307 NULL,
1310 static ssize_t
1311 sample_mdev_dev_show(struct device *dev, struct device_attribute *attr,
1312 char *buf)
1314 if (mdev_from_dev(dev))
1315 return sprintf(buf, "This is MDEV %s\n", dev_name(dev));
1317 return sprintf(buf, "\n");
1320 static DEVICE_ATTR_RO(sample_mdev_dev);
1322 static struct attribute *mdev_dev_attrs[] = {
1323 &dev_attr_sample_mdev_dev.attr,
1324 NULL,
1327 static const struct attribute_group mdev_dev_group = {
1328 .name = "vendor",
1329 .attrs = mdev_dev_attrs,
1332 const struct attribute_group *mdev_dev_groups[] = {
1333 &mdev_dev_group,
1334 NULL,
1337 static ssize_t
1338 name_show(struct kobject *kobj, struct device *dev, char *buf)
1340 char name[MTTY_STRING_LEN];
1341 int i;
1342 const char *name_str[2] = {"Single port serial", "Dual port serial"};
1344 for (i = 0; i < 2; i++) {
1345 snprintf(name, MTTY_STRING_LEN, "%s-%d",
1346 dev_driver_string(dev), i + 1);
1347 if (!strcmp(kobj->name, name))
1348 return sprintf(buf, "%s\n", name_str[i]);
1351 return -EINVAL;
1354 MDEV_TYPE_ATTR_RO(name);
1356 static ssize_t
1357 available_instances_show(struct kobject *kobj, struct device *dev, char *buf)
1359 char name[MTTY_STRING_LEN];
1360 int i;
1361 struct mdev_state *mds;
1362 int ports = 0, used = 0;
1364 for (i = 0; i < 2; i++) {
1365 snprintf(name, MTTY_STRING_LEN, "%s-%d",
1366 dev_driver_string(dev), i + 1);
1367 if (!strcmp(kobj->name, name)) {
1368 ports = i + 1;
1369 break;
1373 if (!ports)
1374 return -EINVAL;
1376 list_for_each_entry(mds, &mdev_devices_list, next)
1377 used += mds->nr_ports;
1379 return sprintf(buf, "%d\n", (MAX_MTTYS - used)/ports);
1382 MDEV_TYPE_ATTR_RO(available_instances);
1385 static ssize_t device_api_show(struct kobject *kobj, struct device *dev,
1386 char *buf)
1388 return sprintf(buf, "%s\n", VFIO_DEVICE_API_PCI_STRING);
1391 MDEV_TYPE_ATTR_RO(device_api);
1393 static struct attribute *mdev_types_attrs[] = {
1394 &mdev_type_attr_name.attr,
1395 &mdev_type_attr_device_api.attr,
1396 &mdev_type_attr_available_instances.attr,
1397 NULL,
1400 static struct attribute_group mdev_type_group1 = {
1401 .name = "1",
1402 .attrs = mdev_types_attrs,
1405 static struct attribute_group mdev_type_group2 = {
1406 .name = "2",
1407 .attrs = mdev_types_attrs,
1410 struct attribute_group *mdev_type_groups[] = {
1411 &mdev_type_group1,
1412 &mdev_type_group2,
1413 NULL,
1416 static const struct mdev_parent_ops mdev_fops = {
1417 .owner = THIS_MODULE,
1418 .dev_attr_groups = mtty_dev_groups,
1419 .mdev_attr_groups = mdev_dev_groups,
1420 .supported_type_groups = mdev_type_groups,
1421 .create = mtty_create,
1422 .remove = mtty_remove,
1423 .open = mtty_open,
1424 .release = mtty_close,
1425 .read = mtty_read,
1426 .write = mtty_write,
1427 .ioctl = mtty_ioctl,
1430 static void mtty_device_release(struct device *dev)
1432 dev_dbg(dev, "mtty: released\n");
1435 static int __init mtty_dev_init(void)
1437 int ret = 0;
1439 pr_info("mtty_dev: %s\n", __func__);
1441 memset(&mtty_dev, 0, sizeof(mtty_dev));
1443 idr_init(&mtty_dev.vd_idr);
1445 ret = alloc_chrdev_region(&mtty_dev.vd_devt, 0, MINORMASK, MTTY_NAME);
1447 if (ret < 0) {
1448 pr_err("Error: failed to register mtty_dev, err:%d\n", ret);
1449 return ret;
1452 cdev_init(&mtty_dev.vd_cdev, &vd_fops);
1453 cdev_add(&mtty_dev.vd_cdev, mtty_dev.vd_devt, MINORMASK);
1455 pr_info("major_number:%d\n", MAJOR(mtty_dev.vd_devt));
1457 mtty_dev.vd_class = class_create(THIS_MODULE, MTTY_CLASS_NAME);
1459 if (IS_ERR(mtty_dev.vd_class)) {
1460 pr_err("Error: failed to register mtty_dev class\n");
1461 ret = PTR_ERR(mtty_dev.vd_class);
1462 goto failed1;
1465 mtty_dev.dev.class = mtty_dev.vd_class;
1466 mtty_dev.dev.release = mtty_device_release;
1467 dev_set_name(&mtty_dev.dev, "%s", MTTY_NAME);
1469 ret = device_register(&mtty_dev.dev);
1470 if (ret)
1471 goto failed2;
1473 ret = mdev_register_device(&mtty_dev.dev, &mdev_fops);
1474 if (ret)
1475 goto failed3;
1477 mutex_init(&mdev_list_lock);
1478 INIT_LIST_HEAD(&mdev_devices_list);
1480 goto all_done;
1482 failed3:
1484 device_unregister(&mtty_dev.dev);
1485 failed2:
1486 class_destroy(mtty_dev.vd_class);
1488 failed1:
1489 cdev_del(&mtty_dev.vd_cdev);
1490 unregister_chrdev_region(mtty_dev.vd_devt, MINORMASK);
1492 all_done:
1493 return ret;
1496 static void __exit mtty_dev_exit(void)
1498 mtty_dev.dev.bus = NULL;
1499 mdev_unregister_device(&mtty_dev.dev);
1501 device_unregister(&mtty_dev.dev);
1502 idr_destroy(&mtty_dev.vd_idr);
1503 cdev_del(&mtty_dev.vd_cdev);
1504 unregister_chrdev_region(mtty_dev.vd_devt, MINORMASK);
1505 class_destroy(mtty_dev.vd_class);
1506 mtty_dev.vd_class = NULL;
1507 pr_info("mtty_dev: Unloaded!\n");
1510 module_init(mtty_dev_init)
1511 module_exit(mtty_dev_exit)
1513 MODULE_LICENSE("GPL v2");
1514 MODULE_INFO(supported, "Test driver that simulate serial port over PCI");
1515 MODULE_VERSION(VERSION_STRING);
1516 MODULE_AUTHOR(DRIVER_AUTHOR);