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   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * Mellanox BlueField SoC TmFifo driver
   4 *
   5 * Copyright (C) 2019 Mellanox Technologies
   6 */
   7
   8#include <linux/acpi.h>
   9#include <linux/bitfield.h>
  10#include <linux/circ_buf.h>
  11#include <linux/efi.h>
  12#include <linux/irq.h>
  13#include <linux/module.h>
  14#include <linux/mutex.h>
  15#include <linux/platform_device.h>
  16#include <linux/types.h>
  17
  18#include <linux/virtio_config.h>
  19#include <linux/virtio_console.h>
  20#include <linux/virtio_ids.h>
  21#include <linux/virtio_net.h>
  22#include <linux/virtio_ring.h>
  23
  24#include "mlxbf-tmfifo-regs.h"
  25
  26/* Vring size. */
  27#define MLXBF_TMFIFO_VRING_SIZE			SZ_1K
  28
  29/* Console Tx buffer size. */
  30#define MLXBF_TMFIFO_CON_TX_BUF_SIZE		SZ_32K
  31
  32/* Console Tx buffer reserved space. */
  33#define MLXBF_TMFIFO_CON_TX_BUF_RSV_SIZE	8
  34
  35/* House-keeping timer interval. */
  36#define MLXBF_TMFIFO_TIMER_INTERVAL		(HZ / 10)
  37
  38/* Virtual devices sharing the TM FIFO. */
  39#define MLXBF_TMFIFO_VDEV_MAX		(VIRTIO_ID_CONSOLE + 1)
  40
  41/*
  42 * Reserve 1/16 of TmFifo space, so console messages are not starved by
  43 * the networking traffic.
  44 */
  45#define MLXBF_TMFIFO_RESERVE_RATIO		16
  46
  47/* Message with data needs at least two words (for header & data). */
  48#define MLXBF_TMFIFO_DATA_MIN_WORDS		2
  49
  50/* ACPI UID for BlueField-3. */
  51#define TMFIFO_BF3_UID				1
  52
  53struct mlxbf_tmfifo;
  54
  55/**
  56 * mlxbf_tmfifo_vring - Structure of the TmFifo virtual ring
  57 * @va: virtual address of the ring
  58 * @dma: dma address of the ring
  59 * @vq: pointer to the virtio virtqueue
  60 * @desc: current descriptor of the pending packet
  61 * @desc_head: head descriptor of the pending packet
  62 * @cur_len: processed length of the current descriptor
  63 * @rem_len: remaining length of the pending packet
  64 * @pkt_len: total length of the pending packet
  65 * @next_avail: next avail descriptor id
  66 * @num: vring size (number of descriptors)
  67 * @align: vring alignment size
  68 * @index: vring index
  69 * @vdev_id: vring virtio id (VIRTIO_ID_xxx)
  70 * @fifo: pointer to the tmfifo structure
  71 */
  72struct mlxbf_tmfifo_vring {
  73	void *va;
  74	dma_addr_t dma;
  75	struct virtqueue *vq;
  76	struct vring_desc *desc;
  77	struct vring_desc *desc_head;
  78	int cur_len;
  79	int rem_len;
  80	u32 pkt_len;
  81	u16 next_avail;
  82	int num;
  83	int align;
  84	int index;
  85	int vdev_id;
  86	struct mlxbf_tmfifo *fifo;
  87};
  88
  89/* Interrupt types. */
  90enum {
  91	MLXBF_TM_RX_LWM_IRQ,
  92	MLXBF_TM_RX_HWM_IRQ,
  93	MLXBF_TM_TX_LWM_IRQ,
  94	MLXBF_TM_TX_HWM_IRQ,
  95	MLXBF_TM_MAX_IRQ
  96};
  97
  98/* Ring types (Rx & Tx). */
  99enum {
 100	MLXBF_TMFIFO_VRING_RX,
 101	MLXBF_TMFIFO_VRING_TX,
 102	MLXBF_TMFIFO_VRING_MAX
 103};
 104
 105/**
 106 * mlxbf_tmfifo_vdev - Structure of the TmFifo virtual device
 107 * @vdev: virtio device, in which the vdev.id.device field has the
 108 *        VIRTIO_ID_xxx id to distinguish the virtual device.
 109 * @status: status of the device
 110 * @features: supported features of the device
 111 * @vrings: array of tmfifo vrings of this device
 112 * @config.cons: virtual console config -
 113 *               select if vdev.id.device is VIRTIO_ID_CONSOLE
 114 * @config.net: virtual network config -
 115 *              select if vdev.id.device is VIRTIO_ID_NET
 116 * @tx_buf: tx buffer used to buffer data before writing into the FIFO
 117 */
 118struct mlxbf_tmfifo_vdev {
 119	struct virtio_device vdev;
 120	u8 status;
 121	u64 features;
 122	struct mlxbf_tmfifo_vring vrings[MLXBF_TMFIFO_VRING_MAX];
 123	union {
 124		struct virtio_console_config cons;
 125		struct virtio_net_config net;
 126	} config;
 127	struct circ_buf tx_buf;
 128};
 129
 130/**
 131 * mlxbf_tmfifo_irq_info - Structure of the interrupt information
 132 * @fifo: pointer to the tmfifo structure
 133 * @irq: interrupt number
 134 * @index: index into the interrupt array
 135 */
 136struct mlxbf_tmfifo_irq_info {
 137	struct mlxbf_tmfifo *fifo;
 138	int irq;
 139	int index;
 140};
 141
 142/**
 143 * mlxbf_tmfifo_io - Structure of the TmFifo IO resource (for both rx & tx)
 144 * @ctl: control register offset (TMFIFO_RX_CTL / TMFIFO_TX_CTL)
 145 * @sts: status register offset (TMFIFO_RX_STS / TMFIFO_TX_STS)
 146 * @data: data register offset (TMFIFO_RX_DATA / TMFIFO_TX_DATA)
 147 */
 148struct mlxbf_tmfifo_io {
 149	void __iomem *ctl;
 150	void __iomem *sts;
 151	void __iomem *data;
 152};
 153
 154/**
 155 * mlxbf_tmfifo - Structure of the TmFifo
 156 * @vdev: array of the virtual devices running over the TmFifo
 157 * @lock: lock to protect the TmFifo access
 158 * @res0: mapped resource block 0
 159 * @res1: mapped resource block 1
 160 * @rx: rx io resource
 161 * @tx: tx io resource
 162 * @rx_fifo_size: number of entries of the Rx FIFO
 163 * @tx_fifo_size: number of entries of the Tx FIFO
 164 * @pend_events: pending bits for deferred events
 165 * @irq_info: interrupt information
 166 * @work: work struct for deferred process
 167 * @timer: background timer
 168 * @vring: Tx/Rx ring
 169 * @spin_lock: Tx/Rx spin lock
 170 * @is_ready: ready flag
 171 */
 172struct mlxbf_tmfifo {
 173	struct mlxbf_tmfifo_vdev *vdev[MLXBF_TMFIFO_VDEV_MAX];
 174	struct mutex lock;		/* TmFifo lock */
 175	void __iomem *res0;
 176	void __iomem *res1;
 177	struct mlxbf_tmfifo_io rx;
 178	struct mlxbf_tmfifo_io tx;
 179	int rx_fifo_size;
 180	int tx_fifo_size;
 181	unsigned long pend_events;
 182	struct mlxbf_tmfifo_irq_info irq_info[MLXBF_TM_MAX_IRQ];
 183	struct work_struct work;
 184	struct timer_list timer;
 185	struct mlxbf_tmfifo_vring *vring[2];
 186	spinlock_t spin_lock[2];	/* spin lock */
 187	bool is_ready;
 188};
 189
 190/**
 191 * mlxbf_tmfifo_msg_hdr - Structure of the TmFifo message header
 192 * @type: message type
 193 * @len: payload length in network byte order. Messages sent into the FIFO
 194 *       will be read by the other side as data stream in the same byte order.
 195 *       The length needs to be encoded into network order so both sides
 196 *       could understand it.
 197 */
 198struct mlxbf_tmfifo_msg_hdr {
 199	u8 type;
 200	__be16 len;
 201	u8 unused[5];
 202} __packed __aligned(sizeof(u64));
 203
 204/*
 205 * Default MAC.
 206 * This MAC address will be read from EFI persistent variable if configured.
 207 * It can also be reconfigured with standard Linux tools.
 208 */
 209static u8 mlxbf_tmfifo_net_default_mac[ETH_ALEN] = {
 210	0x00, 0x1A, 0xCA, 0xFF, 0xFF, 0x01
 211};
 212
 213/* EFI variable name of the MAC address. */
 214static efi_char16_t mlxbf_tmfifo_efi_name[] = L"RshimMacAddr";
 215
 216/* Maximum L2 header length. */
 217#define MLXBF_TMFIFO_NET_L2_OVERHEAD	36
 218
 219/* Supported virtio-net features. */
 220#define MLXBF_TMFIFO_NET_FEATURES \
 221	(BIT_ULL(VIRTIO_NET_F_MTU) | BIT_ULL(VIRTIO_NET_F_STATUS) | \
 222	 BIT_ULL(VIRTIO_NET_F_MAC))
 223
 224#define mlxbf_vdev_to_tmfifo(d) container_of(d, struct mlxbf_tmfifo_vdev, vdev)
 225
 226/* Free vrings of the FIFO device. */
 227static void mlxbf_tmfifo_free_vrings(struct mlxbf_tmfifo *fifo,
 228				     struct mlxbf_tmfifo_vdev *tm_vdev)
 229{
 230	struct mlxbf_tmfifo_vring *vring;
 231	int i, size;
 232
 233	for (i = 0; i < ARRAY_SIZE(tm_vdev->vrings); i++) {
 234		vring = &tm_vdev->vrings[i];
 235		if (vring->va) {
 236			size = vring_size(vring->num, vring->align);
 237			dma_free_coherent(tm_vdev->vdev.dev.parent, size,
 238					  vring->va, vring->dma);
 239			vring->va = NULL;
 240			if (vring->vq) {
 241				vring_del_virtqueue(vring->vq);
 242				vring->vq = NULL;
 243			}
 244		}
 245	}
 246}
 247
 248/* Allocate vrings for the FIFO. */
 249static int mlxbf_tmfifo_alloc_vrings(struct mlxbf_tmfifo *fifo,
 250				     struct mlxbf_tmfifo_vdev *tm_vdev)
 251{
 252	struct mlxbf_tmfifo_vring *vring;
 253	struct device *dev;
 254	dma_addr_t dma;
 255	int i, size;
 256	void *va;
 257
 258	for (i = 0; i < ARRAY_SIZE(tm_vdev->vrings); i++) {
 259		vring = &tm_vdev->vrings[i];
 260		vring->fifo = fifo;
 261		vring->num = MLXBF_TMFIFO_VRING_SIZE;
 262		vring->align = SMP_CACHE_BYTES;
 263		vring->index = i;
 264		vring->vdev_id = tm_vdev->vdev.id.device;
 265		dev = &tm_vdev->vdev.dev;
 266
 267		size = vring_size(vring->num, vring->align);
 268		va = dma_alloc_coherent(dev->parent, size, &dma, GFP_KERNEL);
 269		if (!va) {
 270			mlxbf_tmfifo_free_vrings(fifo, tm_vdev);
 271			dev_err(dev->parent, "dma_alloc_coherent failed\n");
 272			return -ENOMEM;
 273		}
 274
 275		vring->va = va;
 276		vring->dma = dma;
 277	}
 278
 279	return 0;
 280}
 281
 282/* Disable interrupts of the FIFO device. */
 283static void mlxbf_tmfifo_disable_irqs(struct mlxbf_tmfifo *fifo)
 284{
 285	int i, irq;
 286
 287	for (i = 0; i < MLXBF_TM_MAX_IRQ; i++) {
 288		irq = fifo->irq_info[i].irq;
 289		fifo->irq_info[i].irq = 0;
 290		disable_irq(irq);
 291	}
 292}
 293
 294/* Interrupt handler. */
 295static irqreturn_t mlxbf_tmfifo_irq_handler(int irq, void *arg)
 296{
 297	struct mlxbf_tmfifo_irq_info *irq_info = arg;
 298
 299	if (!test_and_set_bit(irq_info->index, &irq_info->fifo->pend_events))
 300		schedule_work(&irq_info->fifo->work);
 301
 302	return IRQ_HANDLED;
 303}
 304
 305/* Get the next packet descriptor from the vring. */
 306static struct vring_desc *
 307mlxbf_tmfifo_get_next_desc(struct mlxbf_tmfifo_vring *vring)
 308{
 309	const struct vring *vr = virtqueue_get_vring(vring->vq);
 310	struct virtio_device *vdev = vring->vq->vdev;
 311	unsigned int idx, head;
 312
 313	if (vring->next_avail == virtio16_to_cpu(vdev, vr->avail->idx))
 314		return NULL;
 315
 316	/* Make sure 'avail->idx' is visible already. */
 317	virtio_rmb(false);
 318
 319	idx = vring->next_avail % vr->num;
 320	head = virtio16_to_cpu(vdev, vr->avail->ring[idx]);
 321	if (WARN_ON(head >= vr->num))
 322		return NULL;
 323
 324	vring->next_avail++;
 325
 326	return &vr->desc[head];
 327}
 328
 329/* Release virtio descriptor. */
 330static void mlxbf_tmfifo_release_desc(struct mlxbf_tmfifo_vring *vring,
 331				      struct vring_desc *desc, u32 len)
 332{
 333	const struct vring *vr = virtqueue_get_vring(vring->vq);
 334	struct virtio_device *vdev = vring->vq->vdev;
 335	u16 idx, vr_idx;
 336
 337	vr_idx = virtio16_to_cpu(vdev, vr->used->idx);
 338	idx = vr_idx % vr->num;
 339	vr->used->ring[idx].id = cpu_to_virtio32(vdev, desc - vr->desc);
 340	vr->used->ring[idx].len = cpu_to_virtio32(vdev, len);
 341
 342	/*
 343	 * Virtio could poll and check the 'idx' to decide whether the desc is
 344	 * done or not. Add a memory barrier here to make sure the update above
 345	 * completes before updating the idx.
 346	 */
 347	virtio_mb(false);
 348	vr->used->idx = cpu_to_virtio16(vdev, vr_idx + 1);
 349}
 350
 351/* Get the total length of the descriptor chain. */
 352static u32 mlxbf_tmfifo_get_pkt_len(struct mlxbf_tmfifo_vring *vring,
 353				    struct vring_desc *desc)
 354{
 355	const struct vring *vr = virtqueue_get_vring(vring->vq);
 356	struct virtio_device *vdev = vring->vq->vdev;
 357	u32 len = 0, idx;
 358
 359	while (desc) {
 360		len += virtio32_to_cpu(vdev, desc->len);
 361		if (!(virtio16_to_cpu(vdev, desc->flags) & VRING_DESC_F_NEXT))
 362			break;
 363		idx = virtio16_to_cpu(vdev, desc->next);
 364		desc = &vr->desc[idx];
 365	}
 366
 367	return len;
 368}
 369
 370static void mlxbf_tmfifo_release_pending_pkt(struct mlxbf_tmfifo_vring *vring)
 371{
 372	struct vring_desc *desc_head;
 373	u32 len = 0;
 374
 375	if (vring->desc_head) {
 376		desc_head = vring->desc_head;
 377		len = vring->pkt_len;
 378	} else {
 379		desc_head = mlxbf_tmfifo_get_next_desc(vring);
 380		len = mlxbf_tmfifo_get_pkt_len(vring, desc_head);
 381	}
 382
 383	if (desc_head)
 384		mlxbf_tmfifo_release_desc(vring, desc_head, len);
 385
 386	vring->pkt_len = 0;
 387	vring->desc = NULL;
 388	vring->desc_head = NULL;
 389}
 390
 391static void mlxbf_tmfifo_init_net_desc(struct mlxbf_tmfifo_vring *vring,
 392				       struct vring_desc *desc, bool is_rx)
 393{
 394	struct virtio_device *vdev = vring->vq->vdev;
 395	struct virtio_net_hdr *net_hdr;
 396
 397	net_hdr = phys_to_virt(virtio64_to_cpu(vdev, desc->addr));
 398	memset(net_hdr, 0, sizeof(*net_hdr));
 399}
 400
 401/* Get and initialize the next packet. */
 402static struct vring_desc *
 403mlxbf_tmfifo_get_next_pkt(struct mlxbf_tmfifo_vring *vring, bool is_rx)
 404{
 405	struct vring_desc *desc;
 406
 407	desc = mlxbf_tmfifo_get_next_desc(vring);
 408	if (desc && is_rx && vring->vdev_id == VIRTIO_ID_NET)
 409		mlxbf_tmfifo_init_net_desc(vring, desc, is_rx);
 410
 411	vring->desc_head = desc;
 412	vring->desc = desc;
 413
 414	return desc;
 415}
 416
 417/* House-keeping timer. */
 418static void mlxbf_tmfifo_timer(struct timer_list *t)
 419{
 420	struct mlxbf_tmfifo *fifo = container_of(t, struct mlxbf_tmfifo, timer);
 421	int rx, tx;
 422
 423	rx = !test_and_set_bit(MLXBF_TM_RX_HWM_IRQ, &fifo->pend_events);
 424	tx = !test_and_set_bit(MLXBF_TM_TX_LWM_IRQ, &fifo->pend_events);
 425
 426	if (rx || tx)
 427		schedule_work(&fifo->work);
 428
 429	mod_timer(&fifo->timer, jiffies + MLXBF_TMFIFO_TIMER_INTERVAL);
 430}
 431
 432/* Copy one console packet into the output buffer. */
 433static void mlxbf_tmfifo_console_output_one(struct mlxbf_tmfifo_vdev *cons,
 434					    struct mlxbf_tmfifo_vring *vring,
 435					    struct vring_desc *desc)
 436{
 437	const struct vring *vr = virtqueue_get_vring(vring->vq);
 438	struct virtio_device *vdev = &cons->vdev;
 439	u32 len, idx, seg;
 440	void *addr;
 441
 442	while (desc) {
 443		addr = phys_to_virt(virtio64_to_cpu(vdev, desc->addr));
 444		len = virtio32_to_cpu(vdev, desc->len);
 445
 446		seg = CIRC_SPACE_TO_END(cons->tx_buf.head, cons->tx_buf.tail,
 447					MLXBF_TMFIFO_CON_TX_BUF_SIZE);
 448		if (len <= seg) {
 449			memcpy(cons->tx_buf.buf + cons->tx_buf.head, addr, len);
 450		} else {
 451			memcpy(cons->tx_buf.buf + cons->tx_buf.head, addr, seg);
 452			addr += seg;
 453			memcpy(cons->tx_buf.buf, addr, len - seg);
 454		}
 455		cons->tx_buf.head = (cons->tx_buf.head + len) %
 456			MLXBF_TMFIFO_CON_TX_BUF_SIZE;
 457
 458		if (!(virtio16_to_cpu(vdev, desc->flags) & VRING_DESC_F_NEXT))
 459			break;
 460		idx = virtio16_to_cpu(vdev, desc->next);
 461		desc = &vr->desc[idx];
 462	}
 463}
 464
 465/* Copy console data into the output buffer. */
 466static void mlxbf_tmfifo_console_output(struct mlxbf_tmfifo_vdev *cons,
 467					struct mlxbf_tmfifo_vring *vring)
 468{
 469	struct vring_desc *desc;
 470	u32 len, avail;
 471
 472	desc = mlxbf_tmfifo_get_next_desc(vring);
 473	while (desc) {
 474		/* Release the packet if not enough space. */
 475		len = mlxbf_tmfifo_get_pkt_len(vring, desc);
 476		avail = CIRC_SPACE(cons->tx_buf.head, cons->tx_buf.tail,
 477				   MLXBF_TMFIFO_CON_TX_BUF_SIZE);
 478		if (len + MLXBF_TMFIFO_CON_TX_BUF_RSV_SIZE > avail) {
 479			mlxbf_tmfifo_release_desc(vring, desc, len);
 480			break;
 481		}
 482
 483		mlxbf_tmfifo_console_output_one(cons, vring, desc);
 484		mlxbf_tmfifo_release_desc(vring, desc, len);
 485		desc = mlxbf_tmfifo_get_next_desc(vring);
 486	}
 487}
 488
 489/* Get the number of available words in Rx FIFO for receiving. */
 490static int mlxbf_tmfifo_get_rx_avail(struct mlxbf_tmfifo *fifo)
 491{
 492	u64 sts;
 493
 494	sts = readq(fifo->rx.sts);
 495	return FIELD_GET(MLXBF_TMFIFO_RX_STS__COUNT_MASK, sts);
 496}
 497
 498/* Get the number of available words in the TmFifo for sending. */
 499static int mlxbf_tmfifo_get_tx_avail(struct mlxbf_tmfifo *fifo, int vdev_id)
 500{
 501	int tx_reserve;
 502	u32 count;
 503	u64 sts;
 504
 505	/* Reserve some room in FIFO for console messages. */
 506	if (vdev_id == VIRTIO_ID_NET)
 507		tx_reserve = fifo->tx_fifo_size / MLXBF_TMFIFO_RESERVE_RATIO;
 508	else
 509		tx_reserve = 1;
 510
 511	sts = readq(fifo->tx.sts);
 512	count = FIELD_GET(MLXBF_TMFIFO_TX_STS__COUNT_MASK, sts);
 513	return fifo->tx_fifo_size - tx_reserve - count;
 514}
 515
 516/* Console Tx (move data from the output buffer into the TmFifo). */
 517static void mlxbf_tmfifo_console_tx(struct mlxbf_tmfifo *fifo, int avail)
 518{
 519	struct mlxbf_tmfifo_msg_hdr hdr;
 520	struct mlxbf_tmfifo_vdev *cons;
 521	unsigned long flags;
 522	int size, seg;
 523	void *addr;
 524	u64 data;
 525
 526	/* Return if not enough space available. */
 527	if (avail < MLXBF_TMFIFO_DATA_MIN_WORDS)
 528		return;
 529
 530	cons = fifo->vdev[VIRTIO_ID_CONSOLE];
 531	if (!cons || !cons->tx_buf.buf)
 532		return;
 533
 534	/* Return if no data to send. */
 535	size = CIRC_CNT(cons->tx_buf.head, cons->tx_buf.tail,
 536			MLXBF_TMFIFO_CON_TX_BUF_SIZE);
 537	if (size == 0)
 538		return;
 539
 540	/* Adjust the size to available space. */
 541	if (size + sizeof(hdr) > avail * sizeof(u64))
 542		size = avail * sizeof(u64) - sizeof(hdr);
 543
 544	/* Write header. */
 545	hdr.type = VIRTIO_ID_CONSOLE;
 546	hdr.len = htons(size);
 547	writeq(*(u64 *)&hdr, fifo->tx.data);
 548
 549	/* Use spin-lock to protect the 'cons->tx_buf'. */
 550	spin_lock_irqsave(&fifo->spin_lock[0], flags);
 551
 552	while (size > 0) {
 553		addr = cons->tx_buf.buf + cons->tx_buf.tail;
 554
 555		seg = CIRC_CNT_TO_END(cons->tx_buf.head, cons->tx_buf.tail,
 556				      MLXBF_TMFIFO_CON_TX_BUF_SIZE);
 557		if (seg >= sizeof(u64)) {
 558			memcpy(&data, addr, sizeof(u64));
 559		} else {
 560			memcpy(&data, addr, seg);
 561			memcpy((u8 *)&data + seg, cons->tx_buf.buf,
 562			       sizeof(u64) - seg);
 563		}
 564		writeq(data, fifo->tx.data);
 565
 566		if (size >= sizeof(u64)) {
 567			cons->tx_buf.tail = (cons->tx_buf.tail + sizeof(u64)) %
 568				MLXBF_TMFIFO_CON_TX_BUF_SIZE;
 569			size -= sizeof(u64);
 570		} else {
 571			cons->tx_buf.tail = (cons->tx_buf.tail + size) %
 572				MLXBF_TMFIFO_CON_TX_BUF_SIZE;
 573			size = 0;
 574		}
 575	}
 576
 577	spin_unlock_irqrestore(&fifo->spin_lock[0], flags);
 578}
 579
 580/* Rx/Tx one word in the descriptor buffer. */
 581static void mlxbf_tmfifo_rxtx_word(struct mlxbf_tmfifo_vring *vring,
 582				   struct vring_desc *desc,
 583				   bool is_rx, int len)
 584{
 585	struct virtio_device *vdev = vring->vq->vdev;
 586	struct mlxbf_tmfifo *fifo = vring->fifo;
 587	void *addr;
 588	u64 data;
 589
 590	/* Get the buffer address of this desc. */
 591	addr = phys_to_virt(virtio64_to_cpu(vdev, desc->addr));
 592
 593	/* Read a word from FIFO for Rx. */
 594	if (is_rx)
 595		data = readq(fifo->rx.data);
 596
 597	if (vring->cur_len + sizeof(u64) <= len) {
 598		/* The whole word. */
 599		if (is_rx)
 600			memcpy(addr + vring->cur_len, &data, sizeof(u64));
 601		else
 602			memcpy(&data, addr + vring->cur_len, sizeof(u64));
 603		vring->cur_len += sizeof(u64);
 604	} else {
 605		/* Leftover bytes. */
 606		if (is_rx)
 607			memcpy(addr + vring->cur_len, &data,
 608			       len - vring->cur_len);
 609		else
 610			memcpy(&data, addr + vring->cur_len,
 611			       len - vring->cur_len);
 612		vring->cur_len = len;
 613	}
 614
 615	/* Write the word into FIFO for Tx. */
 616	if (!is_rx)
 617		writeq(data, fifo->tx.data);
 618}
 619
 620/*
 621 * Rx/Tx packet header.
 622 *
 623 * In Rx case, the packet might be found to belong to a different vring since
 624 * the TmFifo is shared by different services. In such case, the 'vring_change'
 625 * flag is set.
 626 */
 627static void mlxbf_tmfifo_rxtx_header(struct mlxbf_tmfifo_vring *vring,
 628				     struct vring_desc *desc,
 629				     bool is_rx, bool *vring_change)
 630{
 631	struct mlxbf_tmfifo *fifo = vring->fifo;
 632	struct virtio_net_config *config;
 633	struct mlxbf_tmfifo_msg_hdr hdr;
 634	int vdev_id, hdr_len;
 635
 636	/* Read/Write packet header. */
 637	if (is_rx) {
 638		/* Drain one word from the FIFO. */
 639		*(u64 *)&hdr = readq(fifo->rx.data);
 640
 641		/* Skip the length 0 packets (keepalive). */
 642		if (hdr.len == 0)
 643			return;
 644
 645		/* Check packet type. */
 646		if (hdr.type == VIRTIO_ID_NET) {
 647			vdev_id = VIRTIO_ID_NET;
 648			hdr_len = sizeof(struct virtio_net_hdr);
 649			config = &fifo->vdev[vdev_id]->config.net;
 650			/* A legacy-only interface for now. */
 651			if (ntohs(hdr.len) >
 652			    __virtio16_to_cpu(virtio_legacy_is_little_endian(),
 653					      config->mtu) +
 654			    MLXBF_TMFIFO_NET_L2_OVERHEAD)
 655				return;
 656		} else {
 657			vdev_id = VIRTIO_ID_CONSOLE;
 658			hdr_len = 0;
 659		}
 660
 661		/*
 662		 * Check whether the new packet still belongs to this vring.
 663		 * If not, update the pkt_len of the new vring.
 664		 */
 665		if (vdev_id != vring->vdev_id) {
 666			struct mlxbf_tmfifo_vdev *tm_dev2 = fifo->vdev[vdev_id];
 667
 668			if (!tm_dev2)
 669				return;
 670			vring->desc = desc;
 671			vring = &tm_dev2->vrings[MLXBF_TMFIFO_VRING_RX];
 672			*vring_change = true;
 673		}
 674		vring->pkt_len = ntohs(hdr.len) + hdr_len;
 675	} else {
 676		/* Network virtio has an extra header. */
 677		hdr_len = (vring->vdev_id == VIRTIO_ID_NET) ?
 678			   sizeof(struct virtio_net_hdr) : 0;
 679		vring->pkt_len = mlxbf_tmfifo_get_pkt_len(vring, desc);
 680		hdr.type = (vring->vdev_id == VIRTIO_ID_NET) ?
 681			    VIRTIO_ID_NET : VIRTIO_ID_CONSOLE;
 682		hdr.len = htons(vring->pkt_len - hdr_len);
 683		writeq(*(u64 *)&hdr, fifo->tx.data);
 684	}
 685
 686	vring->cur_len = hdr_len;
 687	vring->rem_len = vring->pkt_len;
 688	fifo->vring[is_rx] = vring;
 689}
 690
 691/*
 692 * Rx/Tx one descriptor.
 693 *
 694 * Return true to indicate more data available.
 695 */
 696static bool mlxbf_tmfifo_rxtx_one_desc(struct mlxbf_tmfifo_vring *vring,
 697				       bool is_rx, int *avail)
 698{
 699	const struct vring *vr = virtqueue_get_vring(vring->vq);
 700	struct mlxbf_tmfifo *fifo = vring->fifo;
 701	struct virtio_device *vdev;
 702	bool vring_change = false;
 703	struct vring_desc *desc;
 704	unsigned long flags;
 705	u32 len, idx;
 706
 707	vdev = &fifo->vdev[vring->vdev_id]->vdev;
 708
 709	/* Get the descriptor of the next packet. */
 710	if (!vring->desc) {
 711		desc = mlxbf_tmfifo_get_next_pkt(vring, is_rx);
 712		if (!desc)
 713			return false;
 714	} else {
 715		desc = vring->desc;
 716	}
 717
 718	/* Beginning of a packet. Start to Rx/Tx packet header. */
 719	if (vring->pkt_len == 0) {
 720		mlxbf_tmfifo_rxtx_header(vring, desc, is_rx, &vring_change);
 721		(*avail)--;
 722
 723		/* Return if new packet is for another ring. */
 724		if (vring_change)
 725			return false;
 726		goto mlxbf_tmfifo_desc_done;
 727	}
 728
 729	/* Get the length of this desc. */
 730	len = virtio32_to_cpu(vdev, desc->len);
 731	if (len > vring->rem_len)
 732		len = vring->rem_len;
 733
 734	/* Rx/Tx one word (8 bytes) if not done. */
 735	if (vring->cur_len < len) {
 736		mlxbf_tmfifo_rxtx_word(vring, desc, is_rx, len);
 737		(*avail)--;
 738	}
 739
 740	/* Check again whether it's done. */
 741	if (vring->cur_len == len) {
 742		vring->cur_len = 0;
 743		vring->rem_len -= len;
 744
 745		/* Get the next desc on the chain. */
 746		if (vring->rem_len > 0 &&
 747		    (virtio16_to_cpu(vdev, desc->flags) & VRING_DESC_F_NEXT)) {
 748			idx = virtio16_to_cpu(vdev, desc->next);
 749			desc = &vr->desc[idx];
 750			goto mlxbf_tmfifo_desc_done;
 751		}
 752
 753		/* Done and release the pending packet. */
 754		mlxbf_tmfifo_release_pending_pkt(vring);
 755		desc = NULL;
 756		fifo->vring[is_rx] = NULL;
 757
 758		/*
 759		 * Make sure the load/store are in order before
 760		 * returning back to virtio.
 761		 */
 762		virtio_mb(false);
 763
 764		/* Notify upper layer that packet is done. */
 765		spin_lock_irqsave(&fifo->spin_lock[is_rx], flags);
 766		vring_interrupt(0, vring->vq);
 767		spin_unlock_irqrestore(&fifo->spin_lock[is_rx], flags);
 768	}
 769
 770mlxbf_tmfifo_desc_done:
 771	/* Save the current desc. */
 772	vring->desc = desc;
 773
 774	return true;
 775}
 776
 777/* Rx & Tx processing of a queue. */
 778static void mlxbf_tmfifo_rxtx(struct mlxbf_tmfifo_vring *vring, bool is_rx)
 779{
 780	int avail = 0, devid = vring->vdev_id;
 781	struct mlxbf_tmfifo *fifo;
 782	bool more;
 783
 784	fifo = vring->fifo;
 785
 786	/* Return if vdev is not ready. */
 787	if (!fifo->vdev[devid])
 788		return;
 789
 790	/* Return if another vring is running. */
 791	if (fifo->vring[is_rx] && fifo->vring[is_rx] != vring)
 792		return;
 793
 794	/* Only handle console and network for now. */
 795	if (WARN_ON(devid != VIRTIO_ID_NET && devid != VIRTIO_ID_CONSOLE))
 796		return;
 797
 798	do {
 799		/* Get available FIFO space. */
 800		if (avail == 0) {
 801			if (is_rx)
 802				avail = mlxbf_tmfifo_get_rx_avail(fifo);
 803			else
 804				avail = mlxbf_tmfifo_get_tx_avail(fifo, devid);
 805			if (avail <= 0)
 806				break;
 807		}
 808
 809		/* Console output always comes from the Tx buffer. */
 810		if (!is_rx && devid == VIRTIO_ID_CONSOLE) {
 811			mlxbf_tmfifo_console_tx(fifo, avail);
 812			break;
 813		}
 814
 815		/* Handle one descriptor. */
 816		more = mlxbf_tmfifo_rxtx_one_desc(vring, is_rx, &avail);
 817	} while (more);
 818}
 819
 820/* Handle Rx or Tx queues. */
 821static void mlxbf_tmfifo_work_rxtx(struct mlxbf_tmfifo *fifo, int queue_id,
 822				   int irq_id, bool is_rx)
 823{
 824	struct mlxbf_tmfifo_vdev *tm_vdev;
 825	struct mlxbf_tmfifo_vring *vring;
 826	int i;
 827
 828	if (!test_and_clear_bit(irq_id, &fifo->pend_events) ||
 829	    !fifo->irq_info[irq_id].irq)
 830		return;
 831
 832	for (i = 0; i < MLXBF_TMFIFO_VDEV_MAX; i++) {
 833		tm_vdev = fifo->vdev[i];
 834		if (tm_vdev) {
 835			vring = &tm_vdev->vrings[queue_id];
 836			if (vring->vq)
 837				mlxbf_tmfifo_rxtx(vring, is_rx);
 838		}
 839	}
 840}
 841
 842/* Work handler for Rx and Tx case. */
 843static void mlxbf_tmfifo_work_handler(struct work_struct *work)
 844{
 845	struct mlxbf_tmfifo *fifo;
 846
 847	fifo = container_of(work, struct mlxbf_tmfifo, work);
 848	if (!fifo->is_ready)
 849		return;
 850
 851	mutex_lock(&fifo->lock);
 852
 853	/* Tx (Send data to the TmFifo). */
 854	mlxbf_tmfifo_work_rxtx(fifo, MLXBF_TMFIFO_VRING_TX,
 855			       MLXBF_TM_TX_LWM_IRQ, false);
 856
 857	/* Rx (Receive data from the TmFifo). */
 858	mlxbf_tmfifo_work_rxtx(fifo, MLXBF_TMFIFO_VRING_RX,
 859			       MLXBF_TM_RX_HWM_IRQ, true);
 860
 861	mutex_unlock(&fifo->lock);
 862}
 863
 864/* The notify function is called when new buffers are posted. */
 865static bool mlxbf_tmfifo_virtio_notify(struct virtqueue *vq)
 866{
 867	struct mlxbf_tmfifo_vring *vring = vq->priv;
 868	struct mlxbf_tmfifo_vdev *tm_vdev;
 869	struct mlxbf_tmfifo *fifo;
 870	unsigned long flags;
 871
 872	fifo = vring->fifo;
 873
 874	/*
 875	 * Virtio maintains vrings in pairs, even number ring for Rx
 876	 * and odd number ring for Tx.
 877	 */
 878	if (vring->index & BIT(0)) {
 879		/*
 880		 * Console could make blocking call with interrupts disabled.
 881		 * In such case, the vring needs to be served right away. For
 882		 * other cases, just set the TX LWM bit to start Tx in the
 883		 * worker handler.
 884		 */
 885		if (vring->vdev_id == VIRTIO_ID_CONSOLE) {
 886			spin_lock_irqsave(&fifo->spin_lock[0], flags);
 887			tm_vdev = fifo->vdev[VIRTIO_ID_CONSOLE];
 888			mlxbf_tmfifo_console_output(tm_vdev, vring);
 889			spin_unlock_irqrestore(&fifo->spin_lock[0], flags);
 890		} else if (test_and_set_bit(MLXBF_TM_TX_LWM_IRQ,
 891					    &fifo->pend_events)) {
 892			return true;
 893		}
 894	} else {
 895		if (test_and_set_bit(MLXBF_TM_RX_HWM_IRQ, &fifo->pend_events))
 896			return true;
 897	}
 898
 899	schedule_work(&fifo->work);
 900
 901	return true;
 902}
 903
 904/* Get the array of feature bits for this device. */
 905static u64 mlxbf_tmfifo_virtio_get_features(struct virtio_device *vdev)
 906{
 907	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);
 908
 909	return tm_vdev->features;
 910}
 911
 912/* Confirm device features to use. */
 913static int mlxbf_tmfifo_virtio_finalize_features(struct virtio_device *vdev)
 914{
 915	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);
 916
 917	tm_vdev->features = vdev->features;
 918
 919	return 0;
 920}
 921
 922/* Free virtqueues found by find_vqs(). */
 923static void mlxbf_tmfifo_virtio_del_vqs(struct virtio_device *vdev)
 924{
 925	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);
 926	struct mlxbf_tmfifo_vring *vring;
 927	struct virtqueue *vq;
 928	int i;
 929
 930	for (i = 0; i < ARRAY_SIZE(tm_vdev->vrings); i++) {
 931		vring = &tm_vdev->vrings[i];
 932
 933		/* Release the pending packet. */
 934		if (vring->desc)
 935			mlxbf_tmfifo_release_pending_pkt(vring);
 936		vq = vring->vq;
 937		if (vq) {
 938			vring->vq = NULL;
 939			vring_del_virtqueue(vq);
 940		}
 941	}
 942}
 943
 944/* Create and initialize the virtual queues. */
 945static int mlxbf_tmfifo_virtio_find_vqs(struct virtio_device *vdev,
 946					unsigned int nvqs,
 947					struct virtqueue *vqs[],
 948					vq_callback_t *callbacks[],
 949					const char * const names[],
 950					const bool *ctx,
 951					struct irq_affinity *desc)
 952{
 953	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);
 954	struct mlxbf_tmfifo_vring *vring;
 955	struct virtqueue *vq;
 956	int i, ret, size;
 957
 958	if (nvqs > ARRAY_SIZE(tm_vdev->vrings))
 959		return -EINVAL;
 960
 961	for (i = 0; i < nvqs; ++i) {
 962		if (!names[i]) {
 963			ret = -EINVAL;
 964			goto error;
 965		}
 966		vring = &tm_vdev->vrings[i];
 967
 968		/* zero vring */
 969		size = vring_size(vring->num, vring->align);
 970		memset(vring->va, 0, size);
 971		vq = vring_new_virtqueue(i, vring->num, vring->align, vdev,
 972					 false, false, vring->va,
 973					 mlxbf_tmfifo_virtio_notify,
 974					 callbacks[i], names[i]);
 975		if (!vq) {
 976			dev_err(&vdev->dev, "vring_new_virtqueue failed\n");
 977			ret = -ENOMEM;
 978			goto error;
 979		}
 980
 981		vq->num_max = vring->num;
 982
 983		vqs[i] = vq;
 984		vring->vq = vq;
 985		vq->priv = vring;
 986	}
 987
 988	return 0;
 989
 990error:
 991	mlxbf_tmfifo_virtio_del_vqs(vdev);
 992	return ret;
 993}
 994
 995/* Read the status byte. */
 996static u8 mlxbf_tmfifo_virtio_get_status(struct virtio_device *vdev)
 997{
 998	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);
 999
1000	return tm_vdev->status;
1001}
1002
1003/* Write the status byte. */
1004static void mlxbf_tmfifo_virtio_set_status(struct virtio_device *vdev,
1005					   u8 status)
1006{
1007	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);
1008
1009	tm_vdev->status = status;
1010}
1011
1012/* Reset the device. Not much here for now. */
1013static void mlxbf_tmfifo_virtio_reset(struct virtio_device *vdev)
1014{
1015	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);
1016
1017	tm_vdev->status = 0;
1018}
1019
1020/* Read the value of a configuration field. */
1021static void mlxbf_tmfifo_virtio_get(struct virtio_device *vdev,
1022				    unsigned int offset,
1023				    void *buf,
1024				    unsigned int len)
1025{
1026	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);
1027
1028	if ((u64)offset + len > sizeof(tm_vdev->config))
1029		return;
1030
1031	memcpy(buf, (u8 *)&tm_vdev->config + offset, len);
1032}
1033
1034/* Write the value of a configuration field. */
1035static void mlxbf_tmfifo_virtio_set(struct virtio_device *vdev,
1036				    unsigned int offset,
1037				    const void *buf,
1038				    unsigned int len)
1039{
1040	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);
1041
1042	if ((u64)offset + len > sizeof(tm_vdev->config))
1043		return;
1044
1045	memcpy((u8 *)&tm_vdev->config + offset, buf, len);
1046}
1047
1048static void tmfifo_virtio_dev_release(struct device *device)
1049{
1050	struct virtio_device *vdev =
1051			container_of(device, struct virtio_device, dev);
1052	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);
1053
1054	kfree(tm_vdev);
1055}
1056
1057/* Virtio config operations. */
1058static const struct virtio_config_ops mlxbf_tmfifo_virtio_config_ops = {
1059	.get_features = mlxbf_tmfifo_virtio_get_features,
1060	.finalize_features = mlxbf_tmfifo_virtio_finalize_features,
1061	.find_vqs = mlxbf_tmfifo_virtio_find_vqs,
1062	.del_vqs = mlxbf_tmfifo_virtio_del_vqs,
1063	.reset = mlxbf_tmfifo_virtio_reset,
1064	.set_status = mlxbf_tmfifo_virtio_set_status,
1065	.get_status = mlxbf_tmfifo_virtio_get_status,
1066	.get = mlxbf_tmfifo_virtio_get,
1067	.set = mlxbf_tmfifo_virtio_set,
1068};
1069
1070/* Create vdev for the FIFO. */
1071static int mlxbf_tmfifo_create_vdev(struct device *dev,
1072				    struct mlxbf_tmfifo *fifo,
1073				    int vdev_id, u64 features,
1074				    void *config, u32 size)
1075{
1076	struct mlxbf_tmfifo_vdev *tm_vdev, *reg_dev = NULL;
1077	int ret;
1078
1079	mutex_lock(&fifo->lock);
1080
1081	tm_vdev = fifo->vdev[vdev_id];
1082	if (tm_vdev) {
1083		dev_err(dev, "vdev %d already exists\n", vdev_id);
1084		ret = -EEXIST;
1085		goto fail;
1086	}
1087
1088	tm_vdev = kzalloc(sizeof(*tm_vdev), GFP_KERNEL);
1089	if (!tm_vdev) {
1090		ret = -ENOMEM;
1091		goto fail;
1092	}
1093
1094	tm_vdev->vdev.id.device = vdev_id;
1095	tm_vdev->vdev.config = &mlxbf_tmfifo_virtio_config_ops;
1096	tm_vdev->vdev.dev.parent = dev;
1097	tm_vdev->vdev.dev.release = tmfifo_virtio_dev_release;
1098	tm_vdev->features = features;
1099	if (config)
1100		memcpy(&tm_vdev->config, config, size);
1101
1102	if (mlxbf_tmfifo_alloc_vrings(fifo, tm_vdev)) {
1103		dev_err(dev, "unable to allocate vring\n");
1104		ret = -ENOMEM;
1105		goto vdev_fail;
1106	}
1107
1108	/* Allocate an output buffer for the console device. */
1109	if (vdev_id == VIRTIO_ID_CONSOLE)
1110		tm_vdev->tx_buf.buf = devm_kmalloc(dev,
1111						   MLXBF_TMFIFO_CON_TX_BUF_SIZE,
1112						   GFP_KERNEL);
1113	fifo->vdev[vdev_id] = tm_vdev;
1114
1115	/* Register the virtio device. */
1116	ret = register_virtio_device(&tm_vdev->vdev);
1117	reg_dev = tm_vdev;
1118	if (ret) {
1119		dev_err(dev, "register_virtio_device failed\n");
1120		goto vdev_fail;
1121	}
1122
1123	mutex_unlock(&fifo->lock);
1124	return 0;
1125
1126vdev_fail:
1127	mlxbf_tmfifo_free_vrings(fifo, tm_vdev);
1128	fifo->vdev[vdev_id] = NULL;
1129	if (reg_dev)
1130		put_device(&tm_vdev->vdev.dev);
1131	else
1132		kfree(tm_vdev);
1133fail:
1134	mutex_unlock(&fifo->lock);
1135	return ret;
1136}
1137
1138/* Delete vdev for the FIFO. */
1139static int mlxbf_tmfifo_delete_vdev(struct mlxbf_tmfifo *fifo, int vdev_id)
1140{
1141	struct mlxbf_tmfifo_vdev *tm_vdev;
1142
1143	mutex_lock(&fifo->lock);
1144
1145	/* Unregister vdev. */
1146	tm_vdev = fifo->vdev[vdev_id];
1147	if (tm_vdev) {
1148		unregister_virtio_device(&tm_vdev->vdev);
1149		mlxbf_tmfifo_free_vrings(fifo, tm_vdev);
1150		fifo->vdev[vdev_id] = NULL;
1151	}
1152
1153	mutex_unlock(&fifo->lock);
1154
1155	return 0;
1156}
1157
1158/* Read the configured network MAC address from efi variable. */
1159static void mlxbf_tmfifo_get_cfg_mac(u8 *mac)
1160{
1161	efi_guid_t guid = EFI_GLOBAL_VARIABLE_GUID;
1162	unsigned long size = ETH_ALEN;
1163	u8 buf[ETH_ALEN];
1164	efi_status_t rc;
1165
1166	rc = efi.get_variable(mlxbf_tmfifo_efi_name, &guid, NULL, &size, buf);
1167	if (rc == EFI_SUCCESS && size == ETH_ALEN)
1168		ether_addr_copy(mac, buf);
1169	else
1170		ether_addr_copy(mac, mlxbf_tmfifo_net_default_mac);
1171}
1172
1173/* Set TmFifo thresolds which is used to trigger interrupts. */
1174static void mlxbf_tmfifo_set_threshold(struct mlxbf_tmfifo *fifo)
1175{
1176	u64 ctl;
1177
1178	/* Get Tx FIFO size and set the low/high watermark. */
1179	ctl = readq(fifo->tx.ctl);
1180	fifo->tx_fifo_size =
1181		FIELD_GET(MLXBF_TMFIFO_TX_CTL__MAX_ENTRIES_MASK, ctl);
1182	ctl = (ctl & ~MLXBF_TMFIFO_TX_CTL__LWM_MASK) |
1183		FIELD_PREP(MLXBF_TMFIFO_TX_CTL__LWM_MASK,
1184			   fifo->tx_fifo_size / 2);
1185	ctl = (ctl & ~MLXBF_TMFIFO_TX_CTL__HWM_MASK) |
1186		FIELD_PREP(MLXBF_TMFIFO_TX_CTL__HWM_MASK,
1187			   fifo->tx_fifo_size - 1);
1188	writeq(ctl, fifo->tx.ctl);
1189
1190	/* Get Rx FIFO size and set the low/high watermark. */
1191	ctl = readq(fifo->rx.ctl);
1192	fifo->rx_fifo_size =
1193		FIELD_GET(MLXBF_TMFIFO_RX_CTL__MAX_ENTRIES_MASK, ctl);
1194	ctl = (ctl & ~MLXBF_TMFIFO_RX_CTL__LWM_MASK) |
1195		FIELD_PREP(MLXBF_TMFIFO_RX_CTL__LWM_MASK, 0);
1196	ctl = (ctl & ~MLXBF_TMFIFO_RX_CTL__HWM_MASK) |
1197		FIELD_PREP(MLXBF_TMFIFO_RX_CTL__HWM_MASK, 1);
1198	writeq(ctl, fifo->rx.ctl);
1199}
1200
1201static void mlxbf_tmfifo_cleanup(struct mlxbf_tmfifo *fifo)
1202{
1203	int i;
1204
1205	fifo->is_ready = false;
1206	del_timer_sync(&fifo->timer);
1207	mlxbf_tmfifo_disable_irqs(fifo);
1208	cancel_work_sync(&fifo->work);
1209	for (i = 0; i < MLXBF_TMFIFO_VDEV_MAX; i++)
1210		mlxbf_tmfifo_delete_vdev(fifo, i);
1211}
1212
1213/* Probe the TMFIFO. */
1214static int mlxbf_tmfifo_probe(struct platform_device *pdev)
1215{
1216	struct virtio_net_config net_config;
1217	struct device *dev = &pdev->dev;
1218	struct mlxbf_tmfifo *fifo;
1219	u64 dev_id;
1220	int i, rc;
1221
1222	rc = acpi_dev_uid_to_integer(ACPI_COMPANION(dev), &dev_id);
1223	if (rc) {
1224		dev_err(dev, "Cannot retrieve UID\n");
1225		return rc;
1226	}
1227
1228	fifo = devm_kzalloc(dev, sizeof(*fifo), GFP_KERNEL);
1229	if (!fifo)
1230		return -ENOMEM;
1231
1232	spin_lock_init(&fifo->spin_lock[0]);
1233	spin_lock_init(&fifo->spin_lock[1]);
1234	INIT_WORK(&fifo->work, mlxbf_tmfifo_work_handler);
1235	mutex_init(&fifo->lock);
1236
1237	/* Get the resource of the Rx FIFO. */
1238	fifo->res0 = devm_platform_ioremap_resource(pdev, 0);
1239	if (IS_ERR(fifo->res0))
1240		return PTR_ERR(fifo->res0);
1241
1242	/* Get the resource of the Tx FIFO. */
1243	fifo->res1 = devm_platform_ioremap_resource(pdev, 1);
1244	if (IS_ERR(fifo->res1))
1245		return PTR_ERR(fifo->res1);
1246
1247	if (dev_id == TMFIFO_BF3_UID) {
1248		fifo->rx.ctl = fifo->res1 + MLXBF_TMFIFO_RX_CTL_BF3;
1249		fifo->rx.sts = fifo->res1 + MLXBF_TMFIFO_RX_STS_BF3;
1250		fifo->rx.data = fifo->res0 + MLXBF_TMFIFO_RX_DATA_BF3;
1251		fifo->tx.ctl = fifo->res1 + MLXBF_TMFIFO_TX_CTL_BF3;
1252		fifo->tx.sts = fifo->res1 + MLXBF_TMFIFO_TX_STS_BF3;
1253		fifo->tx.data = fifo->res0 + MLXBF_TMFIFO_TX_DATA_BF3;
1254	} else {
1255		fifo->rx.ctl = fifo->res0 + MLXBF_TMFIFO_RX_CTL;
1256		fifo->rx.sts = fifo->res0 + MLXBF_TMFIFO_RX_STS;
1257		fifo->rx.data = fifo->res0 + MLXBF_TMFIFO_RX_DATA;
1258		fifo->tx.ctl = fifo->res1 + MLXBF_TMFIFO_TX_CTL;
1259		fifo->tx.sts = fifo->res1 + MLXBF_TMFIFO_TX_STS;
1260		fifo->tx.data = fifo->res1 + MLXBF_TMFIFO_TX_DATA;
1261	}
1262
1263	platform_set_drvdata(pdev, fifo);
1264
1265	timer_setup(&fifo->timer, mlxbf_tmfifo_timer, 0);
1266
1267	for (i = 0; i < MLXBF_TM_MAX_IRQ; i++) {
1268		fifo->irq_info[i].index = i;
1269		fifo->irq_info[i].fifo = fifo;
1270		fifo->irq_info[i].irq = platform_get_irq(pdev, i);
1271		rc = devm_request_irq(dev, fifo->irq_info[i].irq,
1272				      mlxbf_tmfifo_irq_handler, 0,
1273				      "tmfifo", &fifo->irq_info[i]);
1274		if (rc) {
1275			dev_err(dev, "devm_request_irq failed\n");
1276			fifo->irq_info[i].irq = 0;
1277			return rc;
1278		}
1279	}
1280
1281	mlxbf_tmfifo_set_threshold(fifo);
1282
1283	/* Create the console vdev. */
1284	rc = mlxbf_tmfifo_create_vdev(dev, fifo, VIRTIO_ID_CONSOLE, 0, NULL, 0);
1285	if (rc)
1286		goto fail;
1287
1288	/* Create the network vdev. */
1289	memset(&net_config, 0, sizeof(net_config));
1290
1291	/* A legacy-only interface for now. */
1292	net_config.mtu = __cpu_to_virtio16(virtio_legacy_is_little_endian(),
1293					   ETH_DATA_LEN);
1294	net_config.status = __cpu_to_virtio16(virtio_legacy_is_little_endian(),
1295					      VIRTIO_NET_S_LINK_UP);
1296	mlxbf_tmfifo_get_cfg_mac(net_config.mac);
1297	rc = mlxbf_tmfifo_create_vdev(dev, fifo, VIRTIO_ID_NET,
1298				      MLXBF_TMFIFO_NET_FEATURES, &net_config,
1299				      sizeof(net_config));
1300	if (rc)
1301		goto fail;
1302
1303	mod_timer(&fifo->timer, jiffies + MLXBF_TMFIFO_TIMER_INTERVAL);
1304
1305	fifo->is_ready = true;
1306	return 0;
1307
1308fail:
1309	mlxbf_tmfifo_cleanup(fifo);
1310	return rc;
1311}
1312
1313/* Device remove function. */
1314static int mlxbf_tmfifo_remove(struct platform_device *pdev)
1315{
1316	struct mlxbf_tmfifo *fifo = platform_get_drvdata(pdev);
1317
1318	mlxbf_tmfifo_cleanup(fifo);
1319
1320	return 0;
1321}
1322
1323static const struct acpi_device_id mlxbf_tmfifo_acpi_match[] = {
1324	{ "MLNXBF01", 0 },
1325	{}
1326};
1327MODULE_DEVICE_TABLE(acpi, mlxbf_tmfifo_acpi_match);
1328
1329static struct platform_driver mlxbf_tmfifo_driver = {
1330	.probe = mlxbf_tmfifo_probe,
1331	.remove = mlxbf_tmfifo_remove,
1332	.driver = {
1333		.name = "bf-tmfifo",
1334		.acpi_match_table = mlxbf_tmfifo_acpi_match,
1335	},
1336};
1337
1338module_platform_driver(mlxbf_tmfifo_driver);
1339
1340MODULE_DESCRIPTION("Mellanox BlueField SoC TmFifo Driver");
1341MODULE_LICENSE("GPL v2");
1342MODULE_AUTHOR("Mellanox Technologies");