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
50struct mlxbf_tmfifo;
51
52/**
53 * mlxbf_tmfifo_vring - Structure of the TmFifo virtual ring
54 * @va: virtual address of the ring
55 * @dma: dma address of the ring
56 * @vq: pointer to the virtio virtqueue
57 * @desc: current descriptor of the pending packet
58 * @desc_head: head descriptor of the pending packet
59 * @drop_desc: dummy desc for packet dropping
60 * @cur_len: processed length of the current descriptor
61 * @rem_len: remaining length of the pending packet
62 * @pkt_len: total length of the pending packet
63 * @next_avail: next avail descriptor id
64 * @num: vring size (number of descriptors)
65 * @align: vring alignment size
66 * @index: vring index
67 * @vdev_id: vring virtio id (VIRTIO_ID_xxx)
68 * @fifo: pointer to the tmfifo structure
69 */
70struct mlxbf_tmfifo_vring {
71	void *va;
72	dma_addr_t dma;
73	struct virtqueue *vq;
74	struct vring_desc *desc;
75	struct vring_desc *desc_head;
76	struct vring_desc drop_desc;
77	int cur_len;
78	int rem_len;
79	u32 pkt_len;
80	u16 next_avail;
81	int num;
82	int align;
83	int index;
84	int vdev_id;
85	struct mlxbf_tmfifo *fifo;
86};
87
88/* Check whether vring is in drop mode. */
89#define IS_VRING_DROP(_r) ({ \
90	typeof(_r) (r) = (_r); \
91	(r->desc_head == &r->drop_desc ? true : false); })
92
93/* A stub length to drop maximum length packet. */
94#define VRING_DROP_DESC_MAX_LEN		GENMASK(15, 0)
95
96/* Interrupt types. */
97enum {
98	MLXBF_TM_RX_LWM_IRQ,
99	MLXBF_TM_RX_HWM_IRQ,
100	MLXBF_TM_TX_LWM_IRQ,
101	MLXBF_TM_TX_HWM_IRQ,
102	MLXBF_TM_MAX_IRQ
103};
104
105/* Ring types (Rx & Tx). */
106enum {
107	MLXBF_TMFIFO_VRING_RX,
108	MLXBF_TMFIFO_VRING_TX,
109	MLXBF_TMFIFO_VRING_MAX
110};
111
112/**
113 * mlxbf_tmfifo_vdev - Structure of the TmFifo virtual device
114 * @vdev: virtio device, in which the vdev.id.device field has the
115 *        VIRTIO_ID_xxx id to distinguish the virtual device.
116 * @status: status of the device
117 * @features: supported features of the device
118 * @vrings: array of tmfifo vrings of this device
119 * @config.cons: virtual console config -
120 *               select if vdev.id.device is VIRTIO_ID_CONSOLE
121 * @config.net: virtual network config -
122 *              select if vdev.id.device is VIRTIO_ID_NET
123 * @tx_buf: tx buffer used to buffer data before writing into the FIFO
124 */
125struct mlxbf_tmfifo_vdev {
126	struct virtio_device vdev;
127	u8 status;
128	u64 features;
129	struct mlxbf_tmfifo_vring vrings[MLXBF_TMFIFO_VRING_MAX];
130	union {
131		struct virtio_console_config cons;
132		struct virtio_net_config net;
133	} config;
134	struct circ_buf tx_buf;
135};
136
137/**
138 * mlxbf_tmfifo_irq_info - Structure of the interrupt information
139 * @fifo: pointer to the tmfifo structure
140 * @irq: interrupt number
141 * @index: index into the interrupt array
142 */
143struct mlxbf_tmfifo_irq_info {
144	struct mlxbf_tmfifo *fifo;
145	int irq;
146	int index;
147};
148
149/**
150 * mlxbf_tmfifo - Structure of the TmFifo
151 * @vdev: array of the virtual devices running over the TmFifo
152 * @lock: lock to protect the TmFifo access
153 * @rx_base: mapped register base address for the Rx FIFO
154 * @tx_base: mapped register base address for the Tx FIFO
155 * @rx_fifo_size: number of entries of the Rx FIFO
156 * @tx_fifo_size: number of entries of the Tx FIFO
157 * @pend_events: pending bits for deferred events
158 * @irq_info: interrupt information
159 * @work: work struct for deferred process
160 * @timer: background timer
161 * @vring: Tx/Rx ring
162 * @spin_lock: Tx/Rx spin lock
163 * @is_ready: ready flag
164 */
165struct mlxbf_tmfifo {
166	struct mlxbf_tmfifo_vdev *vdev[MLXBF_TMFIFO_VDEV_MAX];
167	struct mutex lock;		/* TmFifo lock */
168	void __iomem *rx_base;
169	void __iomem *tx_base;
170	int rx_fifo_size;
171	int tx_fifo_size;
172	unsigned long pend_events;
173	struct mlxbf_tmfifo_irq_info irq_info[MLXBF_TM_MAX_IRQ];
174	struct work_struct work;
175	struct timer_list timer;
176	struct mlxbf_tmfifo_vring *vring[2];
177	spinlock_t spin_lock[2];	/* spin lock */
178	bool is_ready;
179};
180
181/**
182 * mlxbf_tmfifo_msg_hdr - Structure of the TmFifo message header
183 * @type: message type
184 * @len: payload length in network byte order. Messages sent into the FIFO
185 *       will be read by the other side as data stream in the same byte order.
186 *       The length needs to be encoded into network order so both sides
187 *       could understand it.
188 */
189struct mlxbf_tmfifo_msg_hdr {
190	u8 type;
191	__be16 len;
192	u8 unused[5];
193} __packed __aligned(sizeof(u64));
194
195/*
196 * Default MAC.
197 * This MAC address will be read from EFI persistent variable if configured.
198 * It can also be reconfigured with standard Linux tools.
199 */
200static u8 mlxbf_tmfifo_net_default_mac[ETH_ALEN] = {
201	0x00, 0x1A, 0xCA, 0xFF, 0xFF, 0x01
202};
203
204/* EFI variable name of the MAC address. */
205static efi_char16_t mlxbf_tmfifo_efi_name[] = L"RshimMacAddr";
206
207/* Maximum L2 header length. */
208#define MLXBF_TMFIFO_NET_L2_OVERHEAD	(ETH_HLEN + VLAN_HLEN)
209
210/* Supported virtio-net features. */
211#define MLXBF_TMFIFO_NET_FEATURES \
212	(BIT_ULL(VIRTIO_NET_F_MTU) | BIT_ULL(VIRTIO_NET_F_STATUS) | \
213	 BIT_ULL(VIRTIO_NET_F_MAC))
214
215#define mlxbf_vdev_to_tmfifo(d) container_of(d, struct mlxbf_tmfifo_vdev, vdev)
216
217/* Free vrings of the FIFO device. */
218static void mlxbf_tmfifo_free_vrings(struct mlxbf_tmfifo *fifo,
219				     struct mlxbf_tmfifo_vdev *tm_vdev)
220{
221	struct mlxbf_tmfifo_vring *vring;
222	int i, size;
223
224	for (i = 0; i < ARRAY_SIZE(tm_vdev->vrings); i++) {
225		vring = &tm_vdev->vrings[i];
226		if (vring->va) {
227			size = vring_size(vring->num, vring->align);
228			dma_free_coherent(tm_vdev->vdev.dev.parent, size,
229					  vring->va, vring->dma);
230			vring->va = NULL;
231			if (vring->vq) {
232				vring_del_virtqueue(vring->vq);
233				vring->vq = NULL;
234			}
235		}
236	}
237}
238
239/* Allocate vrings for the FIFO. */
240static int mlxbf_tmfifo_alloc_vrings(struct mlxbf_tmfifo *fifo,
241				     struct mlxbf_tmfifo_vdev *tm_vdev)
242{
243	struct mlxbf_tmfifo_vring *vring;
244	struct device *dev;
245	dma_addr_t dma;
246	int i, size;
247	void *va;
248
249	for (i = 0; i < ARRAY_SIZE(tm_vdev->vrings); i++) {
250		vring = &tm_vdev->vrings[i];
251		vring->fifo = fifo;
252		vring->num = MLXBF_TMFIFO_VRING_SIZE;
253		vring->align = SMP_CACHE_BYTES;
254		vring->index = i;
255		vring->vdev_id = tm_vdev->vdev.id.device;
256		vring->drop_desc.len = VRING_DROP_DESC_MAX_LEN;
257		dev = &tm_vdev->vdev.dev;
258
259		size = vring_size(vring->num, vring->align);
260		va = dma_alloc_coherent(dev->parent, size, &dma, GFP_KERNEL);
261		if (!va) {
262			mlxbf_tmfifo_free_vrings(fifo, tm_vdev);
263			dev_err(dev->parent, "dma_alloc_coherent failed\n");
264			return -ENOMEM;
265		}
266
267		vring->va = va;
268		vring->dma = dma;
269	}
270
271	return 0;
272}
273
274/* Disable interrupts of the FIFO device. */
275static void mlxbf_tmfifo_disable_irqs(struct mlxbf_tmfifo *fifo)
276{
277	int i, irq;
278
279	for (i = 0; i < MLXBF_TM_MAX_IRQ; i++) {
280		irq = fifo->irq_info[i].irq;
281		fifo->irq_info[i].irq = 0;
282		disable_irq(irq);
283	}
284}
285
286/* Interrupt handler. */
287static irqreturn_t mlxbf_tmfifo_irq_handler(int irq, void *arg)
288{
289	struct mlxbf_tmfifo_irq_info *irq_info = arg;
290
291	if (!test_and_set_bit(irq_info->index, &irq_info->fifo->pend_events))
292		schedule_work(&irq_info->fifo->work);
293
294	return IRQ_HANDLED;
295}
296
297/* Get the next packet descriptor from the vring. */
298static struct vring_desc *
299mlxbf_tmfifo_get_next_desc(struct mlxbf_tmfifo_vring *vring)
300{
301	const struct vring *vr = virtqueue_get_vring(vring->vq);
302	struct virtio_device *vdev = vring->vq->vdev;
303	unsigned int idx, head;
304
305	if (vring->next_avail == virtio16_to_cpu(vdev, vr->avail->idx))
306		return NULL;
307
308	/* Make sure 'avail->idx' is visible already. */
309	virtio_rmb(false);
310
311	idx = vring->next_avail % vr->num;
312	head = virtio16_to_cpu(vdev, vr->avail->ring[idx]);
313	if (WARN_ON(head >= vr->num))
314		return NULL;
315
316	vring->next_avail++;
317
318	return &vr->desc[head];
319}
320
321/* Release virtio descriptor. */
322static void mlxbf_tmfifo_release_desc(struct mlxbf_tmfifo_vring *vring,
323				      struct vring_desc *desc, u32 len)
324{
325	const struct vring *vr = virtqueue_get_vring(vring->vq);
326	struct virtio_device *vdev = vring->vq->vdev;
327	u16 idx, vr_idx;
328
329	vr_idx = virtio16_to_cpu(vdev, vr->used->idx);
330	idx = vr_idx % vr->num;
331	vr->used->ring[idx].id = cpu_to_virtio32(vdev, desc - vr->desc);
332	vr->used->ring[idx].len = cpu_to_virtio32(vdev, len);
333
334	/*
335	 * Virtio could poll and check the 'idx' to decide whether the desc is
336	 * done or not. Add a memory barrier here to make sure the update above
337	 * completes before updating the idx.
338	 */
339	virtio_mb(false);
340	vr->used->idx = cpu_to_virtio16(vdev, vr_idx + 1);
341}
342
343/* Get the total length of the descriptor chain. */
344static u32 mlxbf_tmfifo_get_pkt_len(struct mlxbf_tmfifo_vring *vring,
345				    struct vring_desc *desc)
346{
347	const struct vring *vr = virtqueue_get_vring(vring->vq);
348	struct virtio_device *vdev = vring->vq->vdev;
349	u32 len = 0, idx;
350
351	while (desc) {
352		len += virtio32_to_cpu(vdev, desc->len);
353		if (!(virtio16_to_cpu(vdev, desc->flags) & VRING_DESC_F_NEXT))
354			break;
355		idx = virtio16_to_cpu(vdev, desc->next);
356		desc = &vr->desc[idx];
357	}
358
359	return len;
360}
361
362static void mlxbf_tmfifo_release_pkt(struct mlxbf_tmfifo_vring *vring)
363{
364	struct vring_desc *desc_head;
365	u32 len = 0;
366
367	if (vring->desc_head) {
368		desc_head = vring->desc_head;
369		len = vring->pkt_len;
370	} else {
371		desc_head = mlxbf_tmfifo_get_next_desc(vring);
372		len = mlxbf_tmfifo_get_pkt_len(vring, desc_head);
373	}
374
375	if (desc_head)
376		mlxbf_tmfifo_release_desc(vring, desc_head, len);
377
378	vring->pkt_len = 0;
379	vring->desc = NULL;
380	vring->desc_head = NULL;
381}
382
383static void mlxbf_tmfifo_init_net_desc(struct mlxbf_tmfifo_vring *vring,
384				       struct vring_desc *desc, bool is_rx)
385{
386	struct virtio_device *vdev = vring->vq->vdev;
387	struct virtio_net_hdr *net_hdr;
388
389	net_hdr = phys_to_virt(virtio64_to_cpu(vdev, desc->addr));
390	memset(net_hdr, 0, sizeof(*net_hdr));
391}
392
393/* Get and initialize the next packet. */
394static struct vring_desc *
395mlxbf_tmfifo_get_next_pkt(struct mlxbf_tmfifo_vring *vring, bool is_rx)
396{
397	struct vring_desc *desc;
398
399	desc = mlxbf_tmfifo_get_next_desc(vring);
400	if (desc && is_rx && vring->vdev_id == VIRTIO_ID_NET)
401		mlxbf_tmfifo_init_net_desc(vring, desc, is_rx);
402
403	vring->desc_head = desc;
404	vring->desc = desc;
405
406	return desc;
407}
408
409/* House-keeping timer. */
410static void mlxbf_tmfifo_timer(struct timer_list *t)
411{
412	struct mlxbf_tmfifo *fifo = container_of(t, struct mlxbf_tmfifo, timer);
413	int rx, tx;
414
415	rx = !test_and_set_bit(MLXBF_TM_RX_HWM_IRQ, &fifo->pend_events);
416	tx = !test_and_set_bit(MLXBF_TM_TX_LWM_IRQ, &fifo->pend_events);
417
418	if (rx || tx)
419		schedule_work(&fifo->work);
420
421	mod_timer(&fifo->timer, jiffies + MLXBF_TMFIFO_TIMER_INTERVAL);
422}
423
424/* Copy one console packet into the output buffer. */
425static void mlxbf_tmfifo_console_output_one(struct mlxbf_tmfifo_vdev *cons,
426					    struct mlxbf_tmfifo_vring *vring,
427					    struct vring_desc *desc)
428{
429	const struct vring *vr = virtqueue_get_vring(vring->vq);
430	struct virtio_device *vdev = &cons->vdev;
431	u32 len, idx, seg;
432	void *addr;
433
434	while (desc) {
435		addr = phys_to_virt(virtio64_to_cpu(vdev, desc->addr));
436		len = virtio32_to_cpu(vdev, desc->len);
437
438		seg = CIRC_SPACE_TO_END(cons->tx_buf.head, cons->tx_buf.tail,
439					MLXBF_TMFIFO_CON_TX_BUF_SIZE);
440		if (len <= seg) {
441			memcpy(cons->tx_buf.buf + cons->tx_buf.head, addr, len);
442		} else {
443			memcpy(cons->tx_buf.buf + cons->tx_buf.head, addr, seg);
444			addr += seg;
445			memcpy(cons->tx_buf.buf, addr, len - seg);
446		}
447		cons->tx_buf.head = (cons->tx_buf.head + len) %
448			MLXBF_TMFIFO_CON_TX_BUF_SIZE;
449
450		if (!(virtio16_to_cpu(vdev, desc->flags) & VRING_DESC_F_NEXT))
451			break;
452		idx = virtio16_to_cpu(vdev, desc->next);
453		desc = &vr->desc[idx];
454	}
455}
456
457/* Copy console data into the output buffer. */
458static void mlxbf_tmfifo_console_output(struct mlxbf_tmfifo_vdev *cons,
459					struct mlxbf_tmfifo_vring *vring)
460{
461	struct vring_desc *desc;
462	u32 len, avail;
463
464	desc = mlxbf_tmfifo_get_next_desc(vring);
465	while (desc) {
466		/* Release the packet if not enough space. */
467		len = mlxbf_tmfifo_get_pkt_len(vring, desc);
468		avail = CIRC_SPACE(cons->tx_buf.head, cons->tx_buf.tail,
469				   MLXBF_TMFIFO_CON_TX_BUF_SIZE);
470		if (len + MLXBF_TMFIFO_CON_TX_BUF_RSV_SIZE > avail) {
471			mlxbf_tmfifo_release_desc(vring, desc, len);
472			break;
473		}
474
475		mlxbf_tmfifo_console_output_one(cons, vring, desc);
476		mlxbf_tmfifo_release_desc(vring, desc, len);
477		desc = mlxbf_tmfifo_get_next_desc(vring);
478	}
479}
480
481/* Get the number of available words in Rx FIFO for receiving. */
482static int mlxbf_tmfifo_get_rx_avail(struct mlxbf_tmfifo *fifo)
483{
484	u64 sts;
485
486	sts = readq(fifo->rx_base + MLXBF_TMFIFO_RX_STS);
487	return FIELD_GET(MLXBF_TMFIFO_RX_STS__COUNT_MASK, sts);
488}
489
490/* Get the number of available words in the TmFifo for sending. */
491static int mlxbf_tmfifo_get_tx_avail(struct mlxbf_tmfifo *fifo, int vdev_id)
492{
493	int tx_reserve;
494	u32 count;
495	u64 sts;
496
497	/* Reserve some room in FIFO for console messages. */
498	if (vdev_id == VIRTIO_ID_NET)
499		tx_reserve = fifo->tx_fifo_size / MLXBF_TMFIFO_RESERVE_RATIO;
500	else
501		tx_reserve = 1;
502
503	sts = readq(fifo->tx_base + MLXBF_TMFIFO_TX_STS);
504	count = FIELD_GET(MLXBF_TMFIFO_TX_STS__COUNT_MASK, sts);
505	return fifo->tx_fifo_size - tx_reserve - count;
506}
507
508/* Console Tx (move data from the output buffer into the TmFifo). */
509static void mlxbf_tmfifo_console_tx(struct mlxbf_tmfifo *fifo, int avail)
510{
511	struct mlxbf_tmfifo_msg_hdr hdr;
512	struct mlxbf_tmfifo_vdev *cons;
513	unsigned long flags;
514	int size, seg;
515	void *addr;
516	u64 data;
517
518	/* Return if not enough space available. */
519	if (avail < MLXBF_TMFIFO_DATA_MIN_WORDS)
520		return;
521
522	cons = fifo->vdev[VIRTIO_ID_CONSOLE];
523	if (!cons || !cons->tx_buf.buf)
524		return;
525
526	/* Return if no data to send. */
527	size = CIRC_CNT(cons->tx_buf.head, cons->tx_buf.tail,
528			MLXBF_TMFIFO_CON_TX_BUF_SIZE);
529	if (size == 0)
530		return;
531
532	/* Adjust the size to available space. */
533	if (size + sizeof(hdr) > avail * sizeof(u64))
534		size = avail * sizeof(u64) - sizeof(hdr);
535
536	/* Write header. */
537	hdr.type = VIRTIO_ID_CONSOLE;
538	hdr.len = htons(size);
539	writeq(*(u64 *)&hdr, fifo->tx_base + MLXBF_TMFIFO_TX_DATA);
540
541	/* Use spin-lock to protect the 'cons->tx_buf'. */
542	spin_lock_irqsave(&fifo->spin_lock[0], flags);
543
544	while (size > 0) {
545		addr = cons->tx_buf.buf + cons->tx_buf.tail;
546
547		seg = CIRC_CNT_TO_END(cons->tx_buf.head, cons->tx_buf.tail,
548				      MLXBF_TMFIFO_CON_TX_BUF_SIZE);
549		if (seg >= sizeof(u64)) {
550			memcpy(&data, addr, sizeof(u64));
551		} else {
552			memcpy(&data, addr, seg);
553			memcpy((u8 *)&data + seg, cons->tx_buf.buf,
554			       sizeof(u64) - seg);
555		}
556		writeq(data, fifo->tx_base + MLXBF_TMFIFO_TX_DATA);
557
558		if (size >= sizeof(u64)) {
559			cons->tx_buf.tail = (cons->tx_buf.tail + sizeof(u64)) %
560				MLXBF_TMFIFO_CON_TX_BUF_SIZE;
561			size -= sizeof(u64);
562		} else {
563			cons->tx_buf.tail = (cons->tx_buf.tail + size) %
564				MLXBF_TMFIFO_CON_TX_BUF_SIZE;
565			size = 0;
566		}
567	}
568
569	spin_unlock_irqrestore(&fifo->spin_lock[0], flags);
570}
571
572/* Rx/Tx one word in the descriptor buffer. */
573static void mlxbf_tmfifo_rxtx_word(struct mlxbf_tmfifo_vring *vring,
574				   struct vring_desc *desc,
575				   bool is_rx, int len)
576{
577	struct virtio_device *vdev = vring->vq->vdev;
578	struct mlxbf_tmfifo *fifo = vring->fifo;
579	void *addr;
580	u64 data;
581
582	/* Get the buffer address of this desc. */
583	addr = phys_to_virt(virtio64_to_cpu(vdev, desc->addr));
584
585	/* Read a word from FIFO for Rx. */
586	if (is_rx)
587		data = readq(fifo->rx_base + MLXBF_TMFIFO_RX_DATA);
588
589	if (vring->cur_len + sizeof(u64) <= len) {
590		/* The whole word. */
591		if (is_rx) {
592			if (!IS_VRING_DROP(vring))
593				memcpy(addr + vring->cur_len, &data,
594				       sizeof(u64));
595		} else {
596			memcpy(&data, addr + vring->cur_len,
597			       sizeof(u64));
598		}
599		vring->cur_len += sizeof(u64);
600	} else {
601		/* Leftover bytes. */
602		if (is_rx) {
603			if (!IS_VRING_DROP(vring))
604				memcpy(addr + vring->cur_len, &data,
605				       len - vring->cur_len);
606		} else {
607			data = 0;
608			memcpy(&data, addr + vring->cur_len,
609			       len - vring->cur_len);
610		}
611		vring->cur_len = len;
612	}
613
614	/* Write the word into FIFO for Tx. */
615	if (!is_rx)
616		writeq(data, fifo->tx_base + MLXBF_TMFIFO_TX_DATA);
617}
618
619/*
620 * Rx/Tx packet header.
621 *
622 * In Rx case, the packet might be found to belong to a different vring since
623 * the TmFifo is shared by different services. In such case, the 'vring_change'
624 * flag is set.
625 */
626static void mlxbf_tmfifo_rxtx_header(struct mlxbf_tmfifo_vring *vring,
627				     struct vring_desc **desc,
628				     bool is_rx, bool *vring_change)
629{
630	struct mlxbf_tmfifo *fifo = vring->fifo;
631	struct virtio_net_config *config;
632	struct mlxbf_tmfifo_msg_hdr hdr;
633	int vdev_id, hdr_len;
634	bool drop_rx = false;
635
636	/* Read/Write packet header. */
637	if (is_rx) {
638		/* Drain one word from the FIFO. */
639		*(u64 *)&hdr = readq(fifo->rx_base + MLXBF_TMFIFO_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				drop_rx = true;
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
675		if (drop_rx && !IS_VRING_DROP(vring)) {
676			if (vring->desc_head)
677				mlxbf_tmfifo_release_pkt(vring);
678			*desc = &vring->drop_desc;
679			vring->desc_head = *desc;
680			vring->desc = *desc;
681		}
682
683		vring->pkt_len = ntohs(hdr.len) + hdr_len;
684	} else {
685		/* Network virtio has an extra header. */
686		hdr_len = (vring->vdev_id == VIRTIO_ID_NET) ?
687			   sizeof(struct virtio_net_hdr) : 0;
688		vring->pkt_len = mlxbf_tmfifo_get_pkt_len(vring, *desc);
689		hdr.type = (vring->vdev_id == VIRTIO_ID_NET) ?
690			    VIRTIO_ID_NET : VIRTIO_ID_CONSOLE;
691		hdr.len = htons(vring->pkt_len - hdr_len);
692		writeq(*(u64 *)&hdr, fifo->tx_base + MLXBF_TMFIFO_TX_DATA);
693	}
694
695	vring->cur_len = hdr_len;
696	vring->rem_len = vring->pkt_len;
697	fifo->vring[is_rx] = vring;
698}
699
700/*
701 * Rx/Tx one descriptor.
702 *
703 * Return true to indicate more data available.
704 */
705static bool mlxbf_tmfifo_rxtx_one_desc(struct mlxbf_tmfifo_vring *vring,
706				       bool is_rx, int *avail)
707{
708	const struct vring *vr = virtqueue_get_vring(vring->vq);
709	struct mlxbf_tmfifo *fifo = vring->fifo;
710	struct virtio_device *vdev;
711	bool vring_change = false;
712	struct vring_desc *desc;
713	unsigned long flags;
714	u32 len, idx;
715
716	vdev = &fifo->vdev[vring->vdev_id]->vdev;
717
718	/* Get the descriptor of the next packet. */
719	if (!vring->desc) {
720		desc = mlxbf_tmfifo_get_next_pkt(vring, is_rx);
721		if (!desc) {
722			/* Drop next Rx packet to avoid stuck. */
723			if (is_rx) {
724				desc = &vring->drop_desc;
725				vring->desc_head = desc;
726				vring->desc = desc;
727			} else {
728				return false;
729			}
730		}
731	} else {
732		desc = vring->desc;
733	}
734
735	/* Beginning of a packet. Start to Rx/Tx packet header. */
736	if (vring->pkt_len == 0) {
737		mlxbf_tmfifo_rxtx_header(vring, &desc, is_rx, &vring_change);
738		(*avail)--;
739
740		/* Return if new packet is for another ring. */
741		if (vring_change)
742			return false;
743		goto mlxbf_tmfifo_desc_done;
744	}
745
746	/* Get the length of this desc. */
747	len = virtio32_to_cpu(vdev, desc->len);
748	if (len > vring->rem_len)
749		len = vring->rem_len;
750
751	/* Rx/Tx one word (8 bytes) if not done. */
752	if (vring->cur_len < len) {
753		mlxbf_tmfifo_rxtx_word(vring, desc, is_rx, len);
754		(*avail)--;
755	}
756
757	/* Check again whether it's done. */
758	if (vring->cur_len == len) {
759		vring->cur_len = 0;
760		vring->rem_len -= len;
761
762		/* Get the next desc on the chain. */
763		if (!IS_VRING_DROP(vring) && vring->rem_len > 0 &&
764		    (virtio16_to_cpu(vdev, desc->flags) & VRING_DESC_F_NEXT)) {
765			idx = virtio16_to_cpu(vdev, desc->next);
766			desc = &vr->desc[idx];
767			goto mlxbf_tmfifo_desc_done;
768		}
769
770		/* Done and release the packet. */
771		desc = NULL;
772		fifo->vring[is_rx] = NULL;
773		if (!IS_VRING_DROP(vring)) {
774			mlxbf_tmfifo_release_pkt(vring);
775		} else {
776			vring->pkt_len = 0;
777			vring->desc_head = NULL;
778			vring->desc = NULL;
779			return false;
780		}
781
782		/*
783		 * Make sure the load/store are in order before
784		 * returning back to virtio.
785		 */
786		virtio_mb(false);
787
788		/* Notify upper layer that packet is done. */
789		spin_lock_irqsave(&fifo->spin_lock[is_rx], flags);
790		vring_interrupt(0, vring->vq);
791		spin_unlock_irqrestore(&fifo->spin_lock[is_rx], flags);
792	}
793
794mlxbf_tmfifo_desc_done:
795	/* Save the current desc. */
796	vring->desc = desc;
797
798	return true;
799}
800
801/* Rx & Tx processing of a queue. */
802static void mlxbf_tmfifo_rxtx(struct mlxbf_tmfifo_vring *vring, bool is_rx)
803{
804	int avail = 0, devid = vring->vdev_id;
805	struct mlxbf_tmfifo *fifo;
806	bool more;
807
808	fifo = vring->fifo;
809
810	/* Return if vdev is not ready. */
811	if (!fifo->vdev[devid])
812		return;
813
814	/* Return if another vring is running. */
815	if (fifo->vring[is_rx] && fifo->vring[is_rx] != vring)
816		return;
817
818	/* Only handle console and network for now. */
819	if (WARN_ON(devid != VIRTIO_ID_NET && devid != VIRTIO_ID_CONSOLE))
820		return;
821
822	do {
823		/* Get available FIFO space. */
824		if (avail == 0) {
825			if (is_rx)
826				avail = mlxbf_tmfifo_get_rx_avail(fifo);
827			else
828				avail = mlxbf_tmfifo_get_tx_avail(fifo, devid);
829			if (avail <= 0)
830				break;
831		}
832
833		/* Console output always comes from the Tx buffer. */
834		if (!is_rx && devid == VIRTIO_ID_CONSOLE) {
835			mlxbf_tmfifo_console_tx(fifo, avail);
836			break;
837		}
838
839		/* Handle one descriptor. */
840		more = mlxbf_tmfifo_rxtx_one_desc(vring, is_rx, &avail);
841	} while (more);
842}
843
844/* Handle Rx or Tx queues. */
845static void mlxbf_tmfifo_work_rxtx(struct mlxbf_tmfifo *fifo, int queue_id,
846				   int irq_id, bool is_rx)
847{
848	struct mlxbf_tmfifo_vdev *tm_vdev;
849	struct mlxbf_tmfifo_vring *vring;
850	int i;
851
852	if (!test_and_clear_bit(irq_id, &fifo->pend_events) ||
853	    !fifo->irq_info[irq_id].irq)
854		return;
855
856	for (i = 0; i < MLXBF_TMFIFO_VDEV_MAX; i++) {
857		tm_vdev = fifo->vdev[i];
858		if (tm_vdev) {
859			vring = &tm_vdev->vrings[queue_id];
860			if (vring->vq)
861				mlxbf_tmfifo_rxtx(vring, is_rx);
862		}
863	}
864}
865
866/* Work handler for Rx and Tx case. */
867static void mlxbf_tmfifo_work_handler(struct work_struct *work)
868{
869	struct mlxbf_tmfifo *fifo;
870
871	fifo = container_of(work, struct mlxbf_tmfifo, work);
872	if (!fifo->is_ready)
873		return;
874
875	mutex_lock(&fifo->lock);
876
877	/* Tx (Send data to the TmFifo). */
878	mlxbf_tmfifo_work_rxtx(fifo, MLXBF_TMFIFO_VRING_TX,
879			       MLXBF_TM_TX_LWM_IRQ, false);
880
881	/* Rx (Receive data from the TmFifo). */
882	mlxbf_tmfifo_work_rxtx(fifo, MLXBF_TMFIFO_VRING_RX,
883			       MLXBF_TM_RX_HWM_IRQ, true);
884
885	mutex_unlock(&fifo->lock);
886}
887
888/* The notify function is called when new buffers are posted. */
889static bool mlxbf_tmfifo_virtio_notify(struct virtqueue *vq)
890{
891	struct mlxbf_tmfifo_vring *vring = vq->priv;
892	struct mlxbf_tmfifo_vdev *tm_vdev;
893	struct mlxbf_tmfifo *fifo;
894	unsigned long flags;
895
896	fifo = vring->fifo;
897
898	/*
899	 * Virtio maintains vrings in pairs, even number ring for Rx
900	 * and odd number ring for Tx.
901	 */
902	if (vring->index & BIT(0)) {
903		/*
904		 * Console could make blocking call with interrupts disabled.
905		 * In such case, the vring needs to be served right away. For
906		 * other cases, just set the TX LWM bit to start Tx in the
907		 * worker handler.
908		 */
909		if (vring->vdev_id == VIRTIO_ID_CONSOLE) {
910			spin_lock_irqsave(&fifo->spin_lock[0], flags);
911			tm_vdev = fifo->vdev[VIRTIO_ID_CONSOLE];
912			mlxbf_tmfifo_console_output(tm_vdev, vring);
913			spin_unlock_irqrestore(&fifo->spin_lock[0], flags);
914			set_bit(MLXBF_TM_TX_LWM_IRQ, &fifo->pend_events);
915		} else if (test_and_set_bit(MLXBF_TM_TX_LWM_IRQ,
916					    &fifo->pend_events)) {
917			return true;
918		}
919	} else {
920		if (test_and_set_bit(MLXBF_TM_RX_HWM_IRQ, &fifo->pend_events))
921			return true;
922	}
923
924	schedule_work(&fifo->work);
925
926	return true;
927}
928
929/* Get the array of feature bits for this device. */
930static u64 mlxbf_tmfifo_virtio_get_features(struct virtio_device *vdev)
931{
932	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);
933
934	return tm_vdev->features;
935}
936
937/* Confirm device features to use. */
938static int mlxbf_tmfifo_virtio_finalize_features(struct virtio_device *vdev)
939{
940	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);
941
942	tm_vdev->features = vdev->features;
943
944	return 0;
945}
946
947/* Free virtqueues found by find_vqs(). */
948static void mlxbf_tmfifo_virtio_del_vqs(struct virtio_device *vdev)
949{
950	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);
951	struct mlxbf_tmfifo_vring *vring;
952	struct virtqueue *vq;
953	int i;
954
955	for (i = 0; i < ARRAY_SIZE(tm_vdev->vrings); i++) {
956		vring = &tm_vdev->vrings[i];
957
958		/* Release the pending packet. */
959		if (vring->desc)
960			mlxbf_tmfifo_release_pkt(vring);
961		vq = vring->vq;
962		if (vq) {
963			vring->vq = NULL;
964			vring_del_virtqueue(vq);
965		}
966	}
967}
968
969/* Create and initialize the virtual queues. */
970static int mlxbf_tmfifo_virtio_find_vqs(struct virtio_device *vdev,
971					unsigned int nvqs,
972					struct virtqueue *vqs[],
973					vq_callback_t *callbacks[],
974					const char * const names[],
975					const bool *ctx,
976					struct irq_affinity *desc)
977{
978	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);
979	struct mlxbf_tmfifo_vring *vring;
980	struct virtqueue *vq;
981	int i, ret, size;
982
983	if (nvqs > ARRAY_SIZE(tm_vdev->vrings))
984		return -EINVAL;
985
986	for (i = 0; i < nvqs; ++i) {
987		if (!names[i]) {
988			ret = -EINVAL;
989			goto error;
990		}
991		vring = &tm_vdev->vrings[i];
992
993		/* zero vring */
994		size = vring_size(vring->num, vring->align);
995		memset(vring->va, 0, size);
996		vq = vring_new_virtqueue(i, vring->num, vring->align, vdev,
997					 false, false, vring->va,
998					 mlxbf_tmfifo_virtio_notify,
999					 callbacks[i], names[i]);
1000		if (!vq) {
1001			dev_err(&vdev->dev, "vring_new_virtqueue failed\n");
1002			ret = -ENOMEM;
1003			goto error;
1004		}
1005
1006		vqs[i] = vq;
1007		vring->vq = vq;
1008		vq->priv = vring;
1009	}
1010
1011	return 0;
1012
1013error:
1014	mlxbf_tmfifo_virtio_del_vqs(vdev);
1015	return ret;
1016}
1017
1018/* Read the status byte. */
1019static u8 mlxbf_tmfifo_virtio_get_status(struct virtio_device *vdev)
1020{
1021	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);
1022
1023	return tm_vdev->status;
1024}
1025
1026/* Write the status byte. */
1027static void mlxbf_tmfifo_virtio_set_status(struct virtio_device *vdev,
1028					   u8 status)
1029{
1030	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);
1031
1032	tm_vdev->status = status;
1033}
1034
1035/* Reset the device. Not much here for now. */
1036static void mlxbf_tmfifo_virtio_reset(struct virtio_device *vdev)
1037{
1038	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);
1039
1040	tm_vdev->status = 0;
1041}
1042
1043/* Read the value of a configuration field. */
1044static void mlxbf_tmfifo_virtio_get(struct virtio_device *vdev,
1045				    unsigned int offset,
1046				    void *buf,
1047				    unsigned int len)
1048{
1049	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);
1050
1051	if ((u64)offset + len > sizeof(tm_vdev->config))
1052		return;
1053
1054	memcpy(buf, (u8 *)&tm_vdev->config + offset, len);
1055}
1056
1057/* Write the value of a configuration field. */
1058static void mlxbf_tmfifo_virtio_set(struct virtio_device *vdev,
1059				    unsigned int offset,
1060				    const void *buf,
1061				    unsigned int len)
1062{
1063	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);
1064
1065	if ((u64)offset + len > sizeof(tm_vdev->config))
1066		return;
1067
1068	memcpy((u8 *)&tm_vdev->config + offset, buf, len);
1069}
1070
1071static void tmfifo_virtio_dev_release(struct device *device)
1072{
1073	struct virtio_device *vdev =
1074			container_of(device, struct virtio_device, dev);
1075	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);
1076
1077	kfree(tm_vdev);
1078}
1079
1080/* Virtio config operations. */
1081static const struct virtio_config_ops mlxbf_tmfifo_virtio_config_ops = {
1082	.get_features = mlxbf_tmfifo_virtio_get_features,
1083	.finalize_features = mlxbf_tmfifo_virtio_finalize_features,
1084	.find_vqs = mlxbf_tmfifo_virtio_find_vqs,
1085	.del_vqs = mlxbf_tmfifo_virtio_del_vqs,
1086	.reset = mlxbf_tmfifo_virtio_reset,
1087	.set_status = mlxbf_tmfifo_virtio_set_status,
1088	.get_status = mlxbf_tmfifo_virtio_get_status,
1089	.get = mlxbf_tmfifo_virtio_get,
1090	.set = mlxbf_tmfifo_virtio_set,
1091};
1092
1093/* Create vdev for the FIFO. */
1094static int mlxbf_tmfifo_create_vdev(struct device *dev,
1095				    struct mlxbf_tmfifo *fifo,
1096				    int vdev_id, u64 features,
1097				    void *config, u32 size)
1098{
1099	struct mlxbf_tmfifo_vdev *tm_vdev, *reg_dev = NULL;
1100	int ret;
1101
1102	mutex_lock(&fifo->lock);
1103
1104	tm_vdev = fifo->vdev[vdev_id];
1105	if (tm_vdev) {
1106		dev_err(dev, "vdev %d already exists\n", vdev_id);
1107		ret = -EEXIST;
1108		goto fail;
1109	}
1110
1111	tm_vdev = kzalloc(sizeof(*tm_vdev), GFP_KERNEL);
1112	if (!tm_vdev) {
1113		ret = -ENOMEM;
1114		goto fail;
1115	}
1116
1117	tm_vdev->vdev.id.device = vdev_id;
1118	tm_vdev->vdev.config = &mlxbf_tmfifo_virtio_config_ops;
1119	tm_vdev->vdev.dev.parent = dev;
1120	tm_vdev->vdev.dev.release = tmfifo_virtio_dev_release;
1121	tm_vdev->features = features;
1122	if (config)
1123		memcpy(&tm_vdev->config, config, size);
1124
1125	if (mlxbf_tmfifo_alloc_vrings(fifo, tm_vdev)) {
1126		dev_err(dev, "unable to allocate vring\n");
1127		ret = -ENOMEM;
1128		goto vdev_fail;
1129	}
1130
1131	/* Allocate an output buffer for the console device. */
1132	if (vdev_id == VIRTIO_ID_CONSOLE)
1133		tm_vdev->tx_buf.buf = devm_kmalloc(dev,
1134						   MLXBF_TMFIFO_CON_TX_BUF_SIZE,
1135						   GFP_KERNEL);
1136	fifo->vdev[vdev_id] = tm_vdev;
1137
1138	/* Register the virtio device. */
1139	ret = register_virtio_device(&tm_vdev->vdev);
1140	reg_dev = tm_vdev;
1141	if (ret) {
1142		dev_err(dev, "register_virtio_device failed\n");
1143		goto vdev_fail;
1144	}
1145
1146	mutex_unlock(&fifo->lock);
1147	return 0;
1148
1149vdev_fail:
1150	mlxbf_tmfifo_free_vrings(fifo, tm_vdev);
1151	fifo->vdev[vdev_id] = NULL;
1152	if (reg_dev)
1153		put_device(&tm_vdev->vdev.dev);
1154	else
1155		kfree(tm_vdev);
1156fail:
1157	mutex_unlock(&fifo->lock);
1158	return ret;
1159}
1160
1161/* Delete vdev for the FIFO. */
1162static int mlxbf_tmfifo_delete_vdev(struct mlxbf_tmfifo *fifo, int vdev_id)
1163{
1164	struct mlxbf_tmfifo_vdev *tm_vdev;
1165
1166	mutex_lock(&fifo->lock);
1167
1168	/* Unregister vdev. */
1169	tm_vdev = fifo->vdev[vdev_id];
1170	if (tm_vdev) {
1171		unregister_virtio_device(&tm_vdev->vdev);
1172		mlxbf_tmfifo_free_vrings(fifo, tm_vdev);
1173		fifo->vdev[vdev_id] = NULL;
1174	}
1175
1176	mutex_unlock(&fifo->lock);
1177
1178	return 0;
1179}
1180
1181/* Read the configured network MAC address from efi variable. */
1182static void mlxbf_tmfifo_get_cfg_mac(u8 *mac)
1183{
1184	efi_guid_t guid = EFI_GLOBAL_VARIABLE_GUID;
1185	unsigned long size = ETH_ALEN;
1186	u8 buf[ETH_ALEN];
1187	efi_status_t rc;
1188
1189	rc = efi.get_variable(mlxbf_tmfifo_efi_name, &guid, NULL, &size, buf);
1190	if (rc == EFI_SUCCESS && size == ETH_ALEN)
1191		ether_addr_copy(mac, buf);
1192	else
1193		ether_addr_copy(mac, mlxbf_tmfifo_net_default_mac);
1194}
1195
1196/* Set TmFifo thresolds which is used to trigger interrupts. */
1197static void mlxbf_tmfifo_set_threshold(struct mlxbf_tmfifo *fifo)
1198{
1199	u64 ctl;
1200
1201	/* Get Tx FIFO size and set the low/high watermark. */
1202	ctl = readq(fifo->tx_base + MLXBF_TMFIFO_TX_CTL);
1203	fifo->tx_fifo_size =
1204		FIELD_GET(MLXBF_TMFIFO_TX_CTL__MAX_ENTRIES_MASK, ctl);
1205	ctl = (ctl & ~MLXBF_TMFIFO_TX_CTL__LWM_MASK) |
1206		FIELD_PREP(MLXBF_TMFIFO_TX_CTL__LWM_MASK,
1207			   fifo->tx_fifo_size / 2);
1208	ctl = (ctl & ~MLXBF_TMFIFO_TX_CTL__HWM_MASK) |
1209		FIELD_PREP(MLXBF_TMFIFO_TX_CTL__HWM_MASK,
1210			   fifo->tx_fifo_size - 1);
1211	writeq(ctl, fifo->tx_base + MLXBF_TMFIFO_TX_CTL);
1212
1213	/* Get Rx FIFO size and set the low/high watermark. */
1214	ctl = readq(fifo->rx_base + MLXBF_TMFIFO_RX_CTL);
1215	fifo->rx_fifo_size =
1216		FIELD_GET(MLXBF_TMFIFO_RX_CTL__MAX_ENTRIES_MASK, ctl);
1217	ctl = (ctl & ~MLXBF_TMFIFO_RX_CTL__LWM_MASK) |
1218		FIELD_PREP(MLXBF_TMFIFO_RX_CTL__LWM_MASK, 0);
1219	ctl = (ctl & ~MLXBF_TMFIFO_RX_CTL__HWM_MASK) |
1220		FIELD_PREP(MLXBF_TMFIFO_RX_CTL__HWM_MASK, 1);
1221	writeq(ctl, fifo->rx_base + MLXBF_TMFIFO_RX_CTL);
1222}
1223
1224static void mlxbf_tmfifo_cleanup(struct mlxbf_tmfifo *fifo)
1225{
1226	int i;
1227
1228	fifo->is_ready = false;
1229	del_timer_sync(&fifo->timer);
1230	mlxbf_tmfifo_disable_irqs(fifo);
1231	cancel_work_sync(&fifo->work);
1232	for (i = 0; i < MLXBF_TMFIFO_VDEV_MAX; i++)
1233		mlxbf_tmfifo_delete_vdev(fifo, i);
1234}
1235
1236/* Probe the TMFIFO. */
1237static int mlxbf_tmfifo_probe(struct platform_device *pdev)
1238{
1239	struct virtio_net_config net_config;
1240	struct device *dev = &pdev->dev;
1241	struct mlxbf_tmfifo *fifo;
1242	int i, rc;
1243
1244	fifo = devm_kzalloc(dev, sizeof(*fifo), GFP_KERNEL);
1245	if (!fifo)
1246		return -ENOMEM;
1247
1248	spin_lock_init(&fifo->spin_lock[0]);
1249	spin_lock_init(&fifo->spin_lock[1]);
1250	INIT_WORK(&fifo->work, mlxbf_tmfifo_work_handler);
1251	mutex_init(&fifo->lock);
1252
1253	/* Get the resource of the Rx FIFO. */
1254	fifo->rx_base = devm_platform_ioremap_resource(pdev, 0);
1255	if (IS_ERR(fifo->rx_base))
1256		return PTR_ERR(fifo->rx_base);
1257
1258	/* Get the resource of the Tx FIFO. */
1259	fifo->tx_base = devm_platform_ioremap_resource(pdev, 1);
1260	if (IS_ERR(fifo->tx_base))
1261		return PTR_ERR(fifo->tx_base);
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");
1343