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1// SPDX-License-Identifier: GPL-2.0+2/*3 * Mellanox BlueField SoC TmFifo driver4 *5 * Copyright (C) 2019 Mellanox Technologies6 */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_1K28 29/* Console Tx buffer size. */30#define MLXBF_TMFIFO_CON_TX_BUF_SIZE		SZ_32K31 32/* Console Tx buffer reserved space. */33#define MLXBF_TMFIFO_CON_TX_BUF_RSV_SIZE	834 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 by43 * the networking traffic.44 */45#define MLXBF_TMFIFO_RESERVE_RATIO		1646 47/* Message with data needs at least two words (for header & data). */48#define MLXBF_TMFIFO_DATA_MIN_WORDS		249 50/* Tx timeout in milliseconds. */51#define TMFIFO_TX_TIMEOUT			200052 53/* ACPI UID for BlueField-3. */54#define TMFIFO_BF3_UID				155 56struct mlxbf_tmfifo;57 58/**59 * struct mlxbf_tmfifo_vring - Structure of the TmFifo virtual ring60 * @va: virtual address of the ring61 * @dma: dma address of the ring62 * @vq: pointer to the virtio virtqueue63 * @desc: current descriptor of the pending packet64 * @desc_head: head descriptor of the pending packet65 * @drop_desc: dummy desc for packet dropping66 * @cur_len: processed length of the current descriptor67 * @rem_len: remaining length of the pending packet68 * @rem_padding: remaining bytes to send as paddings69 * @pkt_len: total length of the pending packet70 * @next_avail: next avail descriptor id71 * @num: vring size (number of descriptors)72 * @align: vring alignment size73 * @index: vring index74 * @vdev_id: vring virtio id (VIRTIO_ID_xxx)75 * @tx_timeout: expire time of last tx packet76 * @fifo: pointer to the tmfifo structure77 */78struct mlxbf_tmfifo_vring {79	void *va;80	dma_addr_t dma;81	struct virtqueue *vq;82	struct vring_desc *desc;83	struct vring_desc *desc_head;84	struct vring_desc drop_desc;85	int cur_len;86	int rem_len;87	int rem_padding;88	u32 pkt_len;89	u16 next_avail;90	int num;91	int align;92	int index;93	int vdev_id;94	unsigned long tx_timeout;95	struct mlxbf_tmfifo *fifo;96};97 98/* Check whether vring is in drop mode. */99#define IS_VRING_DROP(_r) ({ \100	typeof(_r) (r) = (_r); \101	r->desc_head == &r->drop_desc; })102 103/* A stub length to drop maximum length packet. */104#define VRING_DROP_DESC_MAX_LEN		GENMASK(15, 0)105 106/* Interrupt types. */107enum {108	MLXBF_TM_RX_LWM_IRQ,109	MLXBF_TM_RX_HWM_IRQ,110	MLXBF_TM_TX_LWM_IRQ,111	MLXBF_TM_TX_HWM_IRQ,112	MLXBF_TM_MAX_IRQ113};114 115/* Ring types (Rx & Tx). */116enum {117	MLXBF_TMFIFO_VRING_RX,118	MLXBF_TMFIFO_VRING_TX,119	MLXBF_TMFIFO_VRING_MAX120};121 122/**123 * struct mlxbf_tmfifo_vdev - Structure of the TmFifo virtual device124 * @vdev: virtio device, in which the vdev.id.device field has the125 *        VIRTIO_ID_xxx id to distinguish the virtual device.126 * @status: status of the device127 * @features: supported features of the device128 * @vrings: array of tmfifo vrings of this device129 * @config: non-anonymous union for cons and net130 * @config.cons: virtual console config -131 *               select if vdev.id.device is VIRTIO_ID_CONSOLE132 * @config.net: virtual network config -133 *              select if vdev.id.device is VIRTIO_ID_NET134 * @tx_buf: tx buffer used to buffer data before writing into the FIFO135 */136struct mlxbf_tmfifo_vdev {137	struct virtio_device vdev;138	u8 status;139	u64 features;140	struct mlxbf_tmfifo_vring vrings[MLXBF_TMFIFO_VRING_MAX];141	union {142		struct virtio_console_config cons;143		struct virtio_net_config net;144	} config;145	struct circ_buf tx_buf;146};147 148/**149 * struct mlxbf_tmfifo_irq_info - Structure of the interrupt information150 * @fifo: pointer to the tmfifo structure151 * @irq: interrupt number152 * @index: index into the interrupt array153 */154struct mlxbf_tmfifo_irq_info {155	struct mlxbf_tmfifo *fifo;156	int irq;157	int index;158};159 160/**161 * struct mlxbf_tmfifo_io - Structure of the TmFifo IO resource (for both rx & tx)162 * @ctl: control register offset (TMFIFO_RX_CTL / TMFIFO_TX_CTL)163 * @sts: status register offset (TMFIFO_RX_STS / TMFIFO_TX_STS)164 * @data: data register offset (TMFIFO_RX_DATA / TMFIFO_TX_DATA)165 */166struct mlxbf_tmfifo_io {167	void __iomem *ctl;168	void __iomem *sts;169	void __iomem *data;170};171 172/**173 * struct mlxbf_tmfifo - Structure of the TmFifo174 * @vdev: array of the virtual devices running over the TmFifo175 * @lock: lock to protect the TmFifo access176 * @res0: mapped resource block 0177 * @res1: mapped resource block 1178 * @rx: rx io resource179 * @tx: tx io resource180 * @rx_fifo_size: number of entries of the Rx FIFO181 * @tx_fifo_size: number of entries of the Tx FIFO182 * @pend_events: pending bits for deferred events183 * @irq_info: interrupt information184 * @work: work struct for deferred process185 * @timer: background timer186 * @vring: Tx/Rx ring187 * @spin_lock: Tx/Rx spin lock188 * @is_ready: ready flag189 */190struct mlxbf_tmfifo {191	struct mlxbf_tmfifo_vdev *vdev[MLXBF_TMFIFO_VDEV_MAX];192	struct mutex lock;		/* TmFifo lock */193	void __iomem *res0;194	void __iomem *res1;195	struct mlxbf_tmfifo_io rx;196	struct mlxbf_tmfifo_io tx;197	int rx_fifo_size;198	int tx_fifo_size;199	unsigned long pend_events;200	struct mlxbf_tmfifo_irq_info irq_info[MLXBF_TM_MAX_IRQ];201	struct work_struct work;202	struct timer_list timer;203	struct mlxbf_tmfifo_vring *vring[2];204	spinlock_t spin_lock[2];	/* spin lock */205	bool is_ready;206};207 208/**209 * struct mlxbf_tmfifo_msg_hdr - Structure of the TmFifo message header210 * @type: message type211 * @len: payload length in network byte order. Messages sent into the FIFO212 *       will be read by the other side as data stream in the same byte order.213 *       The length needs to be encoded into network order so both sides214 *       could understand it.215 */216struct mlxbf_tmfifo_msg_hdr {217	u8 type;218	__be16 len;219	/* private: */220	u8 unused[5];221} __packed __aligned(sizeof(u64));222 223/*224 * Default MAC.225 * This MAC address will be read from EFI persistent variable if configured.226 * It can also be reconfigured with standard Linux tools.227 */228static u8 mlxbf_tmfifo_net_default_mac[ETH_ALEN] = {229	0x00, 0x1A, 0xCA, 0xFF, 0xFF, 0x01230};231 232/* EFI variable name of the MAC address. */233static efi_char16_t mlxbf_tmfifo_efi_name[] = L"RshimMacAddr";234 235/* Maximum L2 header length. */236#define MLXBF_TMFIFO_NET_L2_OVERHEAD	(ETH_HLEN + VLAN_HLEN)237 238/* Supported virtio-net features. */239#define MLXBF_TMFIFO_NET_FEATURES \240	(BIT_ULL(VIRTIO_NET_F_MTU) | BIT_ULL(VIRTIO_NET_F_STATUS) | \241	 BIT_ULL(VIRTIO_NET_F_MAC))242 243#define mlxbf_vdev_to_tmfifo(d) container_of(d, struct mlxbf_tmfifo_vdev, vdev)244 245/* Free vrings of the FIFO device. */246static void mlxbf_tmfifo_free_vrings(struct mlxbf_tmfifo *fifo,247				     struct mlxbf_tmfifo_vdev *tm_vdev)248{249	struct mlxbf_tmfifo_vring *vring;250	int i, size;251 252	for (i = 0; i < ARRAY_SIZE(tm_vdev->vrings); i++) {253		vring = &tm_vdev->vrings[i];254		if (vring->va) {255			size = vring_size(vring->num, vring->align);256			dma_free_coherent(tm_vdev->vdev.dev.parent, size,257					  vring->va, vring->dma);258			vring->va = NULL;259			if (vring->vq) {260				vring_del_virtqueue(vring->vq);261				vring->vq = NULL;262			}263		}264	}265}266 267/* Allocate vrings for the FIFO. */268static int mlxbf_tmfifo_alloc_vrings(struct mlxbf_tmfifo *fifo,269				     struct mlxbf_tmfifo_vdev *tm_vdev)270{271	struct mlxbf_tmfifo_vring *vring;272	struct device *dev;273	dma_addr_t dma;274	int i, size;275	void *va;276 277	for (i = 0; i < ARRAY_SIZE(tm_vdev->vrings); i++) {278		vring = &tm_vdev->vrings[i];279		vring->fifo = fifo;280		vring->num = MLXBF_TMFIFO_VRING_SIZE;281		vring->align = SMP_CACHE_BYTES;282		vring->index = i;283		vring->vdev_id = tm_vdev->vdev.id.device;284		vring->drop_desc.len = VRING_DROP_DESC_MAX_LEN;285		dev = &tm_vdev->vdev.dev;286 287		size = vring_size(vring->num, vring->align);288		va = dma_alloc_coherent(dev->parent, size, &dma, GFP_KERNEL);289		if (!va) {290			mlxbf_tmfifo_free_vrings(fifo, tm_vdev);291			dev_err(dev->parent, "dma_alloc_coherent failed\n");292			return -ENOMEM;293		}294 295		vring->va = va;296		vring->dma = dma;297	}298 299	return 0;300}301 302/* Disable interrupts of the FIFO device. */303static void mlxbf_tmfifo_disable_irqs(struct mlxbf_tmfifo *fifo)304{305	int i, irq;306 307	for (i = 0; i < MLXBF_TM_MAX_IRQ; i++) {308		irq = fifo->irq_info[i].irq;309		fifo->irq_info[i].irq = 0;310		disable_irq(irq);311	}312}313 314/* Interrupt handler. */315static irqreturn_t mlxbf_tmfifo_irq_handler(int irq, void *arg)316{317	struct mlxbf_tmfifo_irq_info *irq_info = arg;318 319	if (!test_and_set_bit(irq_info->index, &irq_info->fifo->pend_events))320		schedule_work(&irq_info->fifo->work);321 322	return IRQ_HANDLED;323}324 325/* Get the next packet descriptor from the vring. */326static struct vring_desc *327mlxbf_tmfifo_get_next_desc(struct mlxbf_tmfifo_vring *vring)328{329	const struct vring *vr = virtqueue_get_vring(vring->vq);330	struct virtio_device *vdev = vring->vq->vdev;331	unsigned int idx, head;332 333	if (vring->next_avail == virtio16_to_cpu(vdev, vr->avail->idx))334		return NULL;335 336	/* Make sure 'avail->idx' is visible already. */337	virtio_rmb(false);338 339	idx = vring->next_avail % vr->num;340	head = virtio16_to_cpu(vdev, vr->avail->ring[idx]);341	if (WARN_ON(head >= vr->num))342		return NULL;343 344	vring->next_avail++;345 346	return &vr->desc[head];347}348 349/* Release virtio descriptor. */350static void mlxbf_tmfifo_release_desc(struct mlxbf_tmfifo_vring *vring,351				      struct vring_desc *desc, u32 len)352{353	const struct vring *vr = virtqueue_get_vring(vring->vq);354	struct virtio_device *vdev = vring->vq->vdev;355	u16 idx, vr_idx;356 357	vr_idx = virtio16_to_cpu(vdev, vr->used->idx);358	idx = vr_idx % vr->num;359	vr->used->ring[idx].id = cpu_to_virtio32(vdev, desc - vr->desc);360	vr->used->ring[idx].len = cpu_to_virtio32(vdev, len);361 362	/*363	 * Virtio could poll and check the 'idx' to decide whether the desc is364	 * done or not. Add a memory barrier here to make sure the update above365	 * completes before updating the idx.366	 */367	virtio_mb(false);368	vr->used->idx = cpu_to_virtio16(vdev, vr_idx + 1);369}370 371/* Get the total length of the descriptor chain. */372static u32 mlxbf_tmfifo_get_pkt_len(struct mlxbf_tmfifo_vring *vring,373				    struct vring_desc *desc)374{375	const struct vring *vr = virtqueue_get_vring(vring->vq);376	struct virtio_device *vdev = vring->vq->vdev;377	u32 len = 0, idx;378 379	while (desc) {380		len += virtio32_to_cpu(vdev, desc->len);381		if (!(virtio16_to_cpu(vdev, desc->flags) & VRING_DESC_F_NEXT))382			break;383		idx = virtio16_to_cpu(vdev, desc->next);384		desc = &vr->desc[idx];385	}386 387	return len;388}389 390static void mlxbf_tmfifo_release_pkt(struct mlxbf_tmfifo_vring *vring)391{392	struct vring_desc *desc_head;393	u32 len = 0;394 395	if (vring->desc_head) {396		desc_head = vring->desc_head;397		len = vring->pkt_len;398	} else {399		desc_head = mlxbf_tmfifo_get_next_desc(vring);400		len = mlxbf_tmfifo_get_pkt_len(vring, desc_head);401	}402 403	if (desc_head)404		mlxbf_tmfifo_release_desc(vring, desc_head, len);405 406	vring->pkt_len = 0;407	vring->desc = NULL;408	vring->desc_head = NULL;409}410 411static void mlxbf_tmfifo_init_net_desc(struct mlxbf_tmfifo_vring *vring,412				       struct vring_desc *desc, bool is_rx)413{414	struct virtio_device *vdev = vring->vq->vdev;415	struct virtio_net_hdr *net_hdr;416 417	net_hdr = phys_to_virt(virtio64_to_cpu(vdev, desc->addr));418	memset(net_hdr, 0, sizeof(*net_hdr));419}420 421/* Get and initialize the next packet. */422static struct vring_desc *423mlxbf_tmfifo_get_next_pkt(struct mlxbf_tmfifo_vring *vring, bool is_rx)424{425	struct vring_desc *desc;426 427	desc = mlxbf_tmfifo_get_next_desc(vring);428	if (desc && is_rx && vring->vdev_id == VIRTIO_ID_NET)429		mlxbf_tmfifo_init_net_desc(vring, desc, is_rx);430 431	vring->desc_head = desc;432	vring->desc = desc;433 434	return desc;435}436 437/* House-keeping timer. */438static void mlxbf_tmfifo_timer(struct timer_list *t)439{440	struct mlxbf_tmfifo *fifo = container_of(t, struct mlxbf_tmfifo, timer);441	int rx, tx;442 443	rx = !test_and_set_bit(MLXBF_TM_RX_HWM_IRQ, &fifo->pend_events);444	tx = !test_and_set_bit(MLXBF_TM_TX_LWM_IRQ, &fifo->pend_events);445 446	if (rx || tx)447		schedule_work(&fifo->work);448 449	mod_timer(&fifo->timer, jiffies + MLXBF_TMFIFO_TIMER_INTERVAL);450}451 452/* Copy one console packet into the output buffer. */453static void mlxbf_tmfifo_console_output_one(struct mlxbf_tmfifo_vdev *cons,454					    struct mlxbf_tmfifo_vring *vring,455					    struct vring_desc *desc)456{457	const struct vring *vr = virtqueue_get_vring(vring->vq);458	struct virtio_device *vdev = &cons->vdev;459	u32 len, idx, seg;460	void *addr;461 462	while (desc) {463		addr = phys_to_virt(virtio64_to_cpu(vdev, desc->addr));464		len = virtio32_to_cpu(vdev, desc->len);465 466		seg = CIRC_SPACE_TO_END(cons->tx_buf.head, cons->tx_buf.tail,467					MLXBF_TMFIFO_CON_TX_BUF_SIZE);468		if (len <= seg) {469			memcpy(cons->tx_buf.buf + cons->tx_buf.head, addr, len);470		} else {471			memcpy(cons->tx_buf.buf + cons->tx_buf.head, addr, seg);472			addr += seg;473			memcpy(cons->tx_buf.buf, addr, len - seg);474		}475		cons->tx_buf.head = (cons->tx_buf.head + len) %476			MLXBF_TMFIFO_CON_TX_BUF_SIZE;477 478		if (!(virtio16_to_cpu(vdev, desc->flags) & VRING_DESC_F_NEXT))479			break;480		idx = virtio16_to_cpu(vdev, desc->next);481		desc = &vr->desc[idx];482	}483}484 485/* Copy console data into the output buffer. */486static void mlxbf_tmfifo_console_output(struct mlxbf_tmfifo_vdev *cons,487					struct mlxbf_tmfifo_vring *vring)488{489	struct vring_desc *desc;490	u32 len, avail;491 492	desc = mlxbf_tmfifo_get_next_desc(vring);493	while (desc) {494		/* Release the packet if not enough space. */495		len = mlxbf_tmfifo_get_pkt_len(vring, desc);496		avail = CIRC_SPACE(cons->tx_buf.head, cons->tx_buf.tail,497				   MLXBF_TMFIFO_CON_TX_BUF_SIZE);498		if (len + MLXBF_TMFIFO_CON_TX_BUF_RSV_SIZE > avail) {499			mlxbf_tmfifo_release_desc(vring, desc, len);500			break;501		}502 503		mlxbf_tmfifo_console_output_one(cons, vring, desc);504		mlxbf_tmfifo_release_desc(vring, desc, len);505		desc = mlxbf_tmfifo_get_next_desc(vring);506	}507}508 509/* Get the number of available words in Rx FIFO for receiving. */510static int mlxbf_tmfifo_get_rx_avail(struct mlxbf_tmfifo *fifo)511{512	u64 sts;513 514	sts = readq(fifo->rx.sts);515	return FIELD_GET(MLXBF_TMFIFO_RX_STS__COUNT_MASK, sts);516}517 518/* Get the number of available words in the TmFifo for sending. */519static int mlxbf_tmfifo_get_tx_avail(struct mlxbf_tmfifo *fifo, int vdev_id)520{521	int tx_reserve;522	u32 count;523	u64 sts;524 525	/* Reserve some room in FIFO for console messages. */526	if (vdev_id == VIRTIO_ID_NET)527		tx_reserve = fifo->tx_fifo_size / MLXBF_TMFIFO_RESERVE_RATIO;528	else529		tx_reserve = 1;530 531	sts = readq(fifo->tx.sts);532	count = FIELD_GET(MLXBF_TMFIFO_TX_STS__COUNT_MASK, sts);533	return fifo->tx_fifo_size - tx_reserve - count;534}535 536/* Console Tx (move data from the output buffer into the TmFifo). */537static void mlxbf_tmfifo_console_tx(struct mlxbf_tmfifo *fifo, int avail)538{539	struct mlxbf_tmfifo_msg_hdr hdr;540	struct mlxbf_tmfifo_vdev *cons;541	unsigned long flags;542	int size, seg;543	void *addr;544	u64 data;545 546	/* Return if not enough space available. */547	if (avail < MLXBF_TMFIFO_DATA_MIN_WORDS)548		return;549 550	cons = fifo->vdev[VIRTIO_ID_CONSOLE];551	if (!cons || !cons->tx_buf.buf)552		return;553 554	/* Return if no data to send. */555	size = CIRC_CNT(cons->tx_buf.head, cons->tx_buf.tail,556			MLXBF_TMFIFO_CON_TX_BUF_SIZE);557	if (size == 0)558		return;559 560	/* Adjust the size to available space. */561	if (size + sizeof(hdr) > avail * sizeof(u64))562		size = avail * sizeof(u64) - sizeof(hdr);563 564	/* Write header. */565	hdr.type = VIRTIO_ID_CONSOLE;566	hdr.len = htons(size);567	writeq(*(u64 *)&hdr, fifo->tx.data);568 569	/* Use spin-lock to protect the 'cons->tx_buf'. */570	spin_lock_irqsave(&fifo->spin_lock[0], flags);571 572	while (size > 0) {573		addr = cons->tx_buf.buf + cons->tx_buf.tail;574 575		seg = CIRC_CNT_TO_END(cons->tx_buf.head, cons->tx_buf.tail,576				      MLXBF_TMFIFO_CON_TX_BUF_SIZE);577		if (seg >= sizeof(u64)) {578			memcpy(&data, addr, sizeof(u64));579		} else {580			memcpy(&data, addr, seg);581			memcpy((u8 *)&data + seg, cons->tx_buf.buf,582			       sizeof(u64) - seg);583		}584		writeq(data, fifo->tx.data);585 586		if (size >= sizeof(u64)) {587			cons->tx_buf.tail = (cons->tx_buf.tail + sizeof(u64)) %588				MLXBF_TMFIFO_CON_TX_BUF_SIZE;589			size -= sizeof(u64);590		} else {591			cons->tx_buf.tail = (cons->tx_buf.tail + size) %592				MLXBF_TMFIFO_CON_TX_BUF_SIZE;593			size = 0;594		}595	}596 597	spin_unlock_irqrestore(&fifo->spin_lock[0], flags);598}599 600/* Rx/Tx one word in the descriptor buffer. */601static void mlxbf_tmfifo_rxtx_word(struct mlxbf_tmfifo_vring *vring,602				   struct vring_desc *desc,603				   bool is_rx, int len)604{605	struct virtio_device *vdev = vring->vq->vdev;606	struct mlxbf_tmfifo *fifo = vring->fifo;607	void *addr;608	u64 data;609 610	/* Get the buffer address of this desc. */611	addr = phys_to_virt(virtio64_to_cpu(vdev, desc->addr));612 613	/* Read a word from FIFO for Rx. */614	if (is_rx)615		data = readq(fifo->rx.data);616 617	if (vring->cur_len + sizeof(u64) <= len) {618		/* The whole word. */619		if (is_rx) {620			if (!IS_VRING_DROP(vring))621				memcpy(addr + vring->cur_len, &data,622				       sizeof(u64));623		} else {624			memcpy(&data, addr + vring->cur_len,625			       sizeof(u64));626		}627		vring->cur_len += sizeof(u64);628	} else {629		/* Leftover bytes. */630		if (is_rx) {631			if (!IS_VRING_DROP(vring))632				memcpy(addr + vring->cur_len, &data,633				       len - vring->cur_len);634		} else {635			data = 0;636			memcpy(&data, addr + vring->cur_len,637			       len - vring->cur_len);638		}639		vring->cur_len = len;640	}641 642	/* Write the word into FIFO for Tx. */643	if (!is_rx)644		writeq(data, fifo->tx.data);645}646 647/*648 * Rx/Tx packet header.649 *650 * In Rx case, the packet might be found to belong to a different vring since651 * the TmFifo is shared by different services. In such case, the 'vring_change'652 * flag is set.653 */654static void mlxbf_tmfifo_rxtx_header(struct mlxbf_tmfifo_vring *vring,655				     struct vring_desc **desc,656				     bool is_rx, bool *vring_change)657{658	struct mlxbf_tmfifo *fifo = vring->fifo;659	struct virtio_net_config *config;660	struct mlxbf_tmfifo_msg_hdr hdr;661	int vdev_id, hdr_len;662	bool drop_rx = false;663 664	/* Read/Write packet header. */665	if (is_rx) {666		/* Drain one word from the FIFO. */667		*(u64 *)&hdr = readq(fifo->rx.data);668 669		/* Skip the length 0 packets (keepalive). */670		if (hdr.len == 0)671			return;672 673		/* Check packet type. */674		if (hdr.type == VIRTIO_ID_NET) {675			vdev_id = VIRTIO_ID_NET;676			hdr_len = sizeof(struct virtio_net_hdr);677			config = &fifo->vdev[vdev_id]->config.net;678			/* A legacy-only interface for now. */679			if (ntohs(hdr.len) >680			    __virtio16_to_cpu(virtio_legacy_is_little_endian(),681					      config->mtu) +682					      MLXBF_TMFIFO_NET_L2_OVERHEAD)683				drop_rx = true;684		} else {685			vdev_id = VIRTIO_ID_CONSOLE;686			hdr_len = 0;687		}688 689		/*690		 * Check whether the new packet still belongs to this vring.691		 * If not, update the pkt_len of the new vring.692		 */693		if (vdev_id != vring->vdev_id) {694			struct mlxbf_tmfifo_vdev *tm_dev2 = fifo->vdev[vdev_id];695 696			if (!tm_dev2)697				return;698			vring->desc = *desc;699			vring = &tm_dev2->vrings[MLXBF_TMFIFO_VRING_RX];700			*vring_change = true;701		}702 703		if (drop_rx && !IS_VRING_DROP(vring)) {704			if (vring->desc_head)705				mlxbf_tmfifo_release_pkt(vring);706			*desc = &vring->drop_desc;707			vring->desc_head = *desc;708			vring->desc = *desc;709		}710 711		vring->pkt_len = ntohs(hdr.len) + hdr_len;712	} else {713		/* Network virtio has an extra header. */714		hdr_len = (vring->vdev_id == VIRTIO_ID_NET) ?715			   sizeof(struct virtio_net_hdr) : 0;716		vring->pkt_len = mlxbf_tmfifo_get_pkt_len(vring, *desc);717		hdr.type = (vring->vdev_id == VIRTIO_ID_NET) ?718			    VIRTIO_ID_NET : VIRTIO_ID_CONSOLE;719		hdr.len = htons(vring->pkt_len - hdr_len);720		writeq(*(u64 *)&hdr, fifo->tx.data);721	}722 723	vring->cur_len = hdr_len;724	vring->rem_len = vring->pkt_len;725	fifo->vring[is_rx] = vring;726}727 728/*729 * Rx/Tx one descriptor.730 *731 * Return true to indicate more data available.732 */733static bool mlxbf_tmfifo_rxtx_one_desc(struct mlxbf_tmfifo_vring *vring,734				       bool is_rx, int *avail)735{736	const struct vring *vr = virtqueue_get_vring(vring->vq);737	struct mlxbf_tmfifo *fifo = vring->fifo;738	struct virtio_device *vdev;739	bool vring_change = false;740	struct vring_desc *desc;741	unsigned long flags;742	u32 len, idx;743 744	vdev = &fifo->vdev[vring->vdev_id]->vdev;745 746	/* Get the descriptor of the next packet. */747	if (!vring->desc) {748		desc = mlxbf_tmfifo_get_next_pkt(vring, is_rx);749		if (!desc) {750			/* Drop next Rx packet to avoid stuck. */751			if (is_rx) {752				desc = &vring->drop_desc;753				vring->desc_head = desc;754				vring->desc = desc;755			} else {756				return false;757			}758		}759	} else {760		desc = vring->desc;761	}762 763	/* Beginning of a packet. Start to Rx/Tx packet header. */764	if (vring->pkt_len == 0) {765		mlxbf_tmfifo_rxtx_header(vring, &desc, is_rx, &vring_change);766		(*avail)--;767 768		/* Return if new packet is for another ring. */769		if (vring_change)770			return false;771		goto mlxbf_tmfifo_desc_done;772	}773 774	/* Get the length of this desc. */775	len = virtio32_to_cpu(vdev, desc->len);776	if (len > vring->rem_len)777		len = vring->rem_len;778 779	/* Rx/Tx one word (8 bytes) if not done. */780	if (vring->cur_len < len) {781		mlxbf_tmfifo_rxtx_word(vring, desc, is_rx, len);782		(*avail)--;783	}784 785	/* Check again whether it's done. */786	if (vring->cur_len == len) {787		vring->cur_len = 0;788		vring->rem_len -= len;789 790		/* Get the next desc on the chain. */791		if (!IS_VRING_DROP(vring) && vring->rem_len > 0 &&792		    (virtio16_to_cpu(vdev, desc->flags) & VRING_DESC_F_NEXT)) {793			idx = virtio16_to_cpu(vdev, desc->next);794			desc = &vr->desc[idx];795			goto mlxbf_tmfifo_desc_done;796		}797 798		/* Done and release the packet. */799		desc = NULL;800		fifo->vring[is_rx] = NULL;801		if (!IS_VRING_DROP(vring)) {802			mlxbf_tmfifo_release_pkt(vring);803		} else {804			vring->pkt_len = 0;805			vring->desc_head = NULL;806			vring->desc = NULL;807			return false;808		}809 810		/*811		 * Make sure the load/store are in order before812		 * returning back to virtio.813		 */814		virtio_mb(false);815 816		/* Notify upper layer that packet is done. */817		spin_lock_irqsave(&fifo->spin_lock[is_rx], flags);818		vring_interrupt(0, vring->vq);819		spin_unlock_irqrestore(&fifo->spin_lock[is_rx], flags);820	}821 822mlxbf_tmfifo_desc_done:823	/* Save the current desc. */824	vring->desc = desc;825 826	return true;827}828 829static void mlxbf_tmfifo_check_tx_timeout(struct mlxbf_tmfifo_vring *vring)830{831	unsigned long flags;832 833	/* Only handle Tx timeout for network vdev. */834	if (vring->vdev_id != VIRTIO_ID_NET)835		return;836 837	/* Initialize the timeout or return if not expired. */838	if (!vring->tx_timeout) {839		/* Initialize the timeout. */840		vring->tx_timeout = jiffies +841			msecs_to_jiffies(TMFIFO_TX_TIMEOUT);842		return;843	} else if (time_before(jiffies, vring->tx_timeout)) {844		/* Return if not timeout yet. */845		return;846	}847 848	/*849	 * Drop the packet after timeout. The outstanding packet is850	 * released and the remaining bytes will be sent with padding byte 0x00851	 * as a recovery. On the peer(host) side, the padding bytes 0x00 will be852	 * either dropped directly, or appended into existing outstanding packet853	 * thus dropped as corrupted network packet.854	 */855	vring->rem_padding = round_up(vring->rem_len, sizeof(u64));856	mlxbf_tmfifo_release_pkt(vring);857	vring->cur_len = 0;858	vring->rem_len = 0;859	vring->fifo->vring[0] = NULL;860 861	/*862	 * Make sure the load/store are in order before863	 * returning back to virtio.864	 */865	virtio_mb(false);866 867	/* Notify upper layer. */868	spin_lock_irqsave(&vring->fifo->spin_lock[0], flags);869	vring_interrupt(0, vring->vq);870	spin_unlock_irqrestore(&vring->fifo->spin_lock[0], flags);871}872 873/* Rx & Tx processing of a queue. */874static void mlxbf_tmfifo_rxtx(struct mlxbf_tmfifo_vring *vring, bool is_rx)875{876	int avail = 0, devid = vring->vdev_id;877	struct mlxbf_tmfifo *fifo;878	bool more;879 880	fifo = vring->fifo;881 882	/* Return if vdev is not ready. */883	if (!fifo || !fifo->vdev[devid])884		return;885 886	/* Return if another vring is running. */887	if (fifo->vring[is_rx] && fifo->vring[is_rx] != vring)888		return;889 890	/* Only handle console and network for now. */891	if (WARN_ON(devid != VIRTIO_ID_NET && devid != VIRTIO_ID_CONSOLE))892		return;893 894	do {895retry:896		/* Get available FIFO space. */897		if (avail == 0) {898			if (is_rx)899				avail = mlxbf_tmfifo_get_rx_avail(fifo);900			else901				avail = mlxbf_tmfifo_get_tx_avail(fifo, devid);902			if (avail <= 0)903				break;904		}905 906		/* Insert paddings for discarded Tx packet. */907		if (!is_rx) {908			vring->tx_timeout = 0;909			while (vring->rem_padding >= sizeof(u64)) {910				writeq(0, vring->fifo->tx.data);911				vring->rem_padding -= sizeof(u64);912				if (--avail == 0)913					goto retry;914			}915		}916 917		/* Console output always comes from the Tx buffer. */918		if (!is_rx && devid == VIRTIO_ID_CONSOLE) {919			mlxbf_tmfifo_console_tx(fifo, avail);920			break;921		}922 923		/* Handle one descriptor. */924		more = mlxbf_tmfifo_rxtx_one_desc(vring, is_rx, &avail);925	} while (more);926 927	/* Check Tx timeout. */928	if (avail <= 0 && !is_rx)929		mlxbf_tmfifo_check_tx_timeout(vring);930}931 932/* Handle Rx or Tx queues. */933static void mlxbf_tmfifo_work_rxtx(struct mlxbf_tmfifo *fifo, int queue_id,934				   int irq_id, bool is_rx)935{936	struct mlxbf_tmfifo_vdev *tm_vdev;937	struct mlxbf_tmfifo_vring *vring;938	int i;939 940	if (!test_and_clear_bit(irq_id, &fifo->pend_events) ||941	    !fifo->irq_info[irq_id].irq)942		return;943 944	for (i = 0; i < MLXBF_TMFIFO_VDEV_MAX; i++) {945		tm_vdev = fifo->vdev[i];946		if (tm_vdev) {947			vring = &tm_vdev->vrings[queue_id];948			if (vring->vq)949				mlxbf_tmfifo_rxtx(vring, is_rx);950		}951	}952}953 954/* Work handler for Rx and Tx case. */955static void mlxbf_tmfifo_work_handler(struct work_struct *work)956{957	struct mlxbf_tmfifo *fifo;958 959	fifo = container_of(work, struct mlxbf_tmfifo, work);960	if (!fifo->is_ready)961		return;962 963	mutex_lock(&fifo->lock);964 965	/* Tx (Send data to the TmFifo). */966	mlxbf_tmfifo_work_rxtx(fifo, MLXBF_TMFIFO_VRING_TX,967			       MLXBF_TM_TX_LWM_IRQ, false);968 969	/* Rx (Receive data from the TmFifo). */970	mlxbf_tmfifo_work_rxtx(fifo, MLXBF_TMFIFO_VRING_RX,971			       MLXBF_TM_RX_HWM_IRQ, true);972 973	mutex_unlock(&fifo->lock);974}975 976/* The notify function is called when new buffers are posted. */977static bool mlxbf_tmfifo_virtio_notify(struct virtqueue *vq)978{979	struct mlxbf_tmfifo_vring *vring = vq->priv;980	struct mlxbf_tmfifo_vdev *tm_vdev;981	struct mlxbf_tmfifo *fifo;982	unsigned long flags;983 984	fifo = vring->fifo;985 986	/*987	 * Virtio maintains vrings in pairs, even number ring for Rx988	 * and odd number ring for Tx.989	 */990	if (vring->index & BIT(0)) {991		/*992		 * Console could make blocking call with interrupts disabled.993		 * In such case, the vring needs to be served right away. For994		 * other cases, just set the TX LWM bit to start Tx in the995		 * worker handler.996		 */997		if (vring->vdev_id == VIRTIO_ID_CONSOLE) {998			spin_lock_irqsave(&fifo->spin_lock[0], flags);999			tm_vdev = fifo->vdev[VIRTIO_ID_CONSOLE];1000			mlxbf_tmfifo_console_output(tm_vdev, vring);1001			spin_unlock_irqrestore(&fifo->spin_lock[0], flags);1002			set_bit(MLXBF_TM_TX_LWM_IRQ, &fifo->pend_events);1003		} else if (test_and_set_bit(MLXBF_TM_TX_LWM_IRQ,1004					    &fifo->pend_events)) {1005			return true;1006		}1007	} else {1008		if (test_and_set_bit(MLXBF_TM_RX_HWM_IRQ, &fifo->pend_events))1009			return true;1010	}1011 1012	schedule_work(&fifo->work);1013 1014	return true;1015}1016 1017/* Get the array of feature bits for this device. */1018static u64 mlxbf_tmfifo_virtio_get_features(struct virtio_device *vdev)1019{1020	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);1021 1022	return tm_vdev->features;1023}1024 1025/* Confirm device features to use. */1026static int mlxbf_tmfifo_virtio_finalize_features(struct virtio_device *vdev)1027{1028	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);1029 1030	tm_vdev->features = vdev->features;1031 1032	return 0;1033}1034 1035/* Free virtqueues found by find_vqs(). */1036static void mlxbf_tmfifo_virtio_del_vqs(struct virtio_device *vdev)1037{1038	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);1039	struct mlxbf_tmfifo_vring *vring;1040	struct virtqueue *vq;1041	int i;1042 1043	for (i = 0; i < ARRAY_SIZE(tm_vdev->vrings); i++) {1044		vring = &tm_vdev->vrings[i];1045 1046		/* Release the pending packet. */1047		if (vring->desc)1048			mlxbf_tmfifo_release_pkt(vring);1049		vq = vring->vq;1050		if (vq) {1051			vring->vq = NULL;1052			vring_del_virtqueue(vq);1053		}1054	}1055}1056 1057/* Create and initialize the virtual queues. */1058static int mlxbf_tmfifo_virtio_find_vqs(struct virtio_device *vdev,1059					unsigned int nvqs,1060					struct virtqueue *vqs[],1061					struct virtqueue_info vqs_info[],1062					struct irq_affinity *desc)1063{1064	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);1065	struct mlxbf_tmfifo_vring *vring;1066	struct virtqueue *vq;1067	int i, ret, size;1068 1069	if (nvqs > ARRAY_SIZE(tm_vdev->vrings))1070		return -EINVAL;1071 1072	for (i = 0; i < nvqs; ++i) {1073		struct virtqueue_info *vqi = &vqs_info[i];1074 1075		if (!vqi->name) {1076			ret = -EINVAL;1077			goto error;1078		}1079		vring = &tm_vdev->vrings[i];1080 1081		/* zero vring */1082		size = vring_size(vring->num, vring->align);1083		memset(vring->va, 0, size);1084		vq = vring_new_virtqueue(i, vring->num, vring->align, vdev,1085					 false, false, vring->va,1086					 mlxbf_tmfifo_virtio_notify,1087					 vqi->callback, vqi->name);1088		if (!vq) {1089			dev_err(&vdev->dev, "vring_new_virtqueue failed\n");1090			ret = -ENOMEM;1091			goto error;1092		}1093 1094		vq->num_max = vring->num;1095 1096		vq->priv = vring;1097 1098		/* Make vq update visible before using it. */1099		virtio_mb(false);1100 1101		vqs[i] = vq;1102		vring->vq = vq;1103	}1104 1105	return 0;1106 1107error:1108	mlxbf_tmfifo_virtio_del_vqs(vdev);1109	return ret;1110}1111 1112/* Read the status byte. */1113static u8 mlxbf_tmfifo_virtio_get_status(struct virtio_device *vdev)1114{1115	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);1116 1117	return tm_vdev->status;1118}1119 1120/* Write the status byte. */1121static void mlxbf_tmfifo_virtio_set_status(struct virtio_device *vdev,1122					   u8 status)1123{1124	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);1125 1126	tm_vdev->status = status;1127}1128 1129/* Reset the device. Not much here for now. */1130static void mlxbf_tmfifo_virtio_reset(struct virtio_device *vdev)1131{1132	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);1133 1134	tm_vdev->status = 0;1135}1136 1137/* Read the value of a configuration field. */1138static void mlxbf_tmfifo_virtio_get(struct virtio_device *vdev,1139				    unsigned int offset,1140				    void *buf,1141				    unsigned int len)1142{1143	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);1144 1145	if ((u64)offset + len > sizeof(tm_vdev->config))1146		return;1147 1148	memcpy(buf, (u8 *)&tm_vdev->config + offset, len);1149}1150 1151/* Write the value of a configuration field. */1152static void mlxbf_tmfifo_virtio_set(struct virtio_device *vdev,1153				    unsigned int offset,1154				    const void *buf,1155				    unsigned int len)1156{1157	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);1158 1159	if ((u64)offset + len > sizeof(tm_vdev->config))1160		return;1161 1162	memcpy((u8 *)&tm_vdev->config + offset, buf, len);1163}1164 1165static void tmfifo_virtio_dev_release(struct device *device)1166{1167	struct virtio_device *vdev =1168			container_of(device, struct virtio_device, dev);1169	struct mlxbf_tmfifo_vdev *tm_vdev = mlxbf_vdev_to_tmfifo(vdev);1170 1171	kfree(tm_vdev);1172}1173 1174/* Virtio config operations. */1175static const struct virtio_config_ops mlxbf_tmfifo_virtio_config_ops = {1176	.get_features = mlxbf_tmfifo_virtio_get_features,1177	.finalize_features = mlxbf_tmfifo_virtio_finalize_features,1178	.find_vqs = mlxbf_tmfifo_virtio_find_vqs,1179	.del_vqs = mlxbf_tmfifo_virtio_del_vqs,1180	.reset = mlxbf_tmfifo_virtio_reset,1181	.set_status = mlxbf_tmfifo_virtio_set_status,1182	.get_status = mlxbf_tmfifo_virtio_get_status,1183	.get = mlxbf_tmfifo_virtio_get,1184	.set = mlxbf_tmfifo_virtio_set,1185};1186 1187/* Create vdev for the FIFO. */1188static int mlxbf_tmfifo_create_vdev(struct device *dev,1189				    struct mlxbf_tmfifo *fifo,1190				    int vdev_id, u64 features,1191				    void *config, u32 size)1192{1193	struct mlxbf_tmfifo_vdev *tm_vdev, *reg_dev = NULL;1194	int ret;1195 1196	mutex_lock(&fifo->lock);1197 1198	tm_vdev = fifo->vdev[vdev_id];1199	if (tm_vdev) {1200		dev_err(dev, "vdev %d already exists\n", vdev_id);1201		ret = -EEXIST;1202		goto fail;1203	}1204 1205	tm_vdev = kzalloc(sizeof(*tm_vdev), GFP_KERNEL);1206	if (!tm_vdev) {1207		ret = -ENOMEM;1208		goto fail;1209	}1210 1211	tm_vdev->vdev.id.device = vdev_id;1212	tm_vdev->vdev.config = &mlxbf_tmfifo_virtio_config_ops;1213	tm_vdev->vdev.dev.parent = dev;1214	tm_vdev->vdev.dev.release = tmfifo_virtio_dev_release;1215	tm_vdev->features = features;1216	if (config)1217		memcpy(&tm_vdev->config, config, size);1218 1219	if (mlxbf_tmfifo_alloc_vrings(fifo, tm_vdev)) {1220		dev_err(dev, "unable to allocate vring\n");1221		ret = -ENOMEM;1222		goto vdev_fail;1223	}1224 1225	/* Allocate an output buffer for the console device. */1226	if (vdev_id == VIRTIO_ID_CONSOLE)1227		tm_vdev->tx_buf.buf = devm_kmalloc(dev,1228						   MLXBF_TMFIFO_CON_TX_BUF_SIZE,1229						   GFP_KERNEL);1230	fifo->vdev[vdev_id] = tm_vdev;1231 1232	/* Register the virtio device. */1233	ret = register_virtio_device(&tm_vdev->vdev);1234	reg_dev = tm_vdev;1235	if (ret) {1236		dev_err(dev, "register_virtio_device failed\n");1237		goto vdev_fail;1238	}1239 1240	mutex_unlock(&fifo->lock);1241	return 0;1242 1243vdev_fail:1244	mlxbf_tmfifo_free_vrings(fifo, tm_vdev);1245	fifo->vdev[vdev_id] = NULL;1246	if (reg_dev)1247		put_device(&tm_vdev->vdev.dev);1248	else1249		kfree(tm_vdev);1250fail:1251	mutex_unlock(&fifo->lock);1252	return ret;1253}1254 1255/* Delete vdev for the FIFO. */1256static int mlxbf_tmfifo_delete_vdev(struct mlxbf_tmfifo *fifo, int vdev_id)1257{1258	struct mlxbf_tmfifo_vdev *tm_vdev;1259 1260	mutex_lock(&fifo->lock);1261 1262	/* Unregister vdev. */1263	tm_vdev = fifo->vdev[vdev_id];1264	if (tm_vdev) {1265		unregister_virtio_device(&tm_vdev->vdev);1266		mlxbf_tmfifo_free_vrings(fifo, tm_vdev);1267		fifo->vdev[vdev_id] = NULL;1268	}1269 1270	mutex_unlock(&fifo->lock);1271 1272	return 0;1273}1274 1275/* Read the configured network MAC address from efi variable. */1276static void mlxbf_tmfifo_get_cfg_mac(u8 *mac)1277{1278	efi_guid_t guid = EFI_GLOBAL_VARIABLE_GUID;1279	unsigned long size = ETH_ALEN;1280	u8 buf[ETH_ALEN];1281	efi_status_t rc;1282 1283	rc = efi.get_variable(mlxbf_tmfifo_efi_name, &guid, NULL, &size, buf);1284	if (rc == EFI_SUCCESS && size == ETH_ALEN)1285		ether_addr_copy(mac, buf);1286	else1287		ether_addr_copy(mac, mlxbf_tmfifo_net_default_mac);1288}1289 1290/* Set TmFifo thresolds which is used to trigger interrupts. */1291static void mlxbf_tmfifo_set_threshold(struct mlxbf_tmfifo *fifo)1292{1293	u64 ctl;1294 1295	/* Get Tx FIFO size and set the low/high watermark. */1296	ctl = readq(fifo->tx.ctl);1297	fifo->tx_fifo_size =1298		FIELD_GET(MLXBF_TMFIFO_TX_CTL__MAX_ENTRIES_MASK, ctl);1299	ctl = (ctl & ~MLXBF_TMFIFO_TX_CTL__LWM_MASK) |1300		FIELD_PREP(MLXBF_TMFIFO_TX_CTL__LWM_MASK,1301			   fifo->tx_fifo_size / 2);1302	ctl = (ctl & ~MLXBF_TMFIFO_TX_CTL__HWM_MASK) |1303		FIELD_PREP(MLXBF_TMFIFO_TX_CTL__HWM_MASK,1304			   fifo->tx_fifo_size - 1);1305	writeq(ctl, fifo->tx.ctl);1306 1307	/* Get Rx FIFO size and set the low/high watermark. */1308	ctl = readq(fifo->rx.ctl);1309	fifo->rx_fifo_size =1310		FIELD_GET(MLXBF_TMFIFO_RX_CTL__MAX_ENTRIES_MASK, ctl);1311	ctl = (ctl & ~MLXBF_TMFIFO_RX_CTL__LWM_MASK) |1312		FIELD_PREP(MLXBF_TMFIFO_RX_CTL__LWM_MASK, 0);1313	ctl = (ctl & ~MLXBF_TMFIFO_RX_CTL__HWM_MASK) |1314		FIELD_PREP(MLXBF_TMFIFO_RX_CTL__HWM_MASK, 1);1315	writeq(ctl, fifo->rx.ctl);1316}1317 1318static void mlxbf_tmfifo_cleanup(struct mlxbf_tmfifo *fifo)1319{1320	int i;1321 1322	fifo->is_ready = false;1323	del_timer_sync(&fifo->timer);1324	mlxbf_tmfifo_disable_irqs(fifo);1325	cancel_work_sync(&fifo->work);1326	for (i = 0; i < MLXBF_TMFIFO_VDEV_MAX; i++)1327		mlxbf_tmfifo_delete_vdev(fifo, i);1328}1329 1330/* Probe the TMFIFO. */1331static int mlxbf_tmfifo_probe(struct platform_device *pdev)1332{1333	struct virtio_net_config net_config;1334	struct device *dev = &pdev->dev;1335	struct mlxbf_tmfifo *fifo;1336	u64 dev_id;1337	int i, rc;1338 1339	rc = acpi_dev_uid_to_integer(ACPI_COMPANION(dev), &dev_id);1340	if (rc) {1341		dev_err(dev, "Cannot retrieve UID\n");1342		return rc;1343	}1344 1345	fifo = devm_kzalloc(dev, sizeof(*fifo), GFP_KERNEL);1346	if (!fifo)1347		return -ENOMEM;1348 1349	spin_lock_init(&fifo->spin_lock[0]);1350	spin_lock_init(&fifo->spin_lock[1]);1351	INIT_WORK(&fifo->work, mlxbf_tmfifo_work_handler);1352	mutex_init(&fifo->lock);1353 1354	/* Get the resource of the Rx FIFO. */1355	fifo->res0 = devm_platform_ioremap_resource(pdev, 0);1356	if (IS_ERR(fifo->res0))1357		return PTR_ERR(fifo->res0);1358 1359	/* Get the resource of the Tx FIFO. */1360	fifo->res1 = devm_platform_ioremap_resource(pdev, 1);1361	if (IS_ERR(fifo->res1))1362		return PTR_ERR(fifo->res1);1363 1364	if (dev_id == TMFIFO_BF3_UID) {1365		fifo->rx.ctl = fifo->res1 + MLXBF_TMFIFO_RX_CTL_BF3;1366		fifo->rx.sts = fifo->res1 + MLXBF_TMFIFO_RX_STS_BF3;1367		fifo->rx.data = fifo->res0 + MLXBF_TMFIFO_RX_DATA_BF3;1368		fifo->tx.ctl = fifo->res1 + MLXBF_TMFIFO_TX_CTL_BF3;1369		fifo->tx.sts = fifo->res1 + MLXBF_TMFIFO_TX_STS_BF3;1370		fifo->tx.data = fifo->res0 + MLXBF_TMFIFO_TX_DATA_BF3;1371	} else {1372		fifo->rx.ctl = fifo->res0 + MLXBF_TMFIFO_RX_CTL;1373		fifo->rx.sts = fifo->res0 + MLXBF_TMFIFO_RX_STS;1374		fifo->rx.data = fifo->res0 + MLXBF_TMFIFO_RX_DATA;1375		fifo->tx.ctl = fifo->res1 + MLXBF_TMFIFO_TX_CTL;1376		fifo->tx.sts = fifo->res1 + MLXBF_TMFIFO_TX_STS;1377		fifo->tx.data = fifo->res1 + MLXBF_TMFIFO_TX_DATA;1378	}1379 1380	platform_set_drvdata(pdev, fifo);1381 1382	timer_setup(&fifo->timer, mlxbf_tmfifo_timer, 0);1383 1384	for (i = 0; i < MLXBF_TM_MAX_IRQ; i++) {1385		fifo->irq_info[i].index = i;1386		fifo->irq_info[i].fifo = fifo;1387		fifo->irq_info[i].irq = platform_get_irq(pdev, i);1388		rc = devm_request_irq(dev, fifo->irq_info[i].irq,1389				      mlxbf_tmfifo_irq_handler, 0,1390				      "tmfifo", &fifo->irq_info[i]);1391		if (rc) {1392			dev_err(dev, "devm_request_irq failed\n");1393			fifo->irq_info[i].irq = 0;1394			return rc;1395		}1396	}1397 1398	mlxbf_tmfifo_set_threshold(fifo);1399 1400	/* Create the console vdev. */1401	rc = mlxbf_tmfifo_create_vdev(dev, fifo, VIRTIO_ID_CONSOLE, 0, NULL, 0);1402	if (rc)1403		goto fail;1404 1405	/* Create the network vdev. */1406	memset(&net_config, 0, sizeof(net_config));1407 1408	/* A legacy-only interface for now. */1409	net_config.mtu = __cpu_to_virtio16(virtio_legacy_is_little_endian(),1410					   ETH_DATA_LEN);1411	net_config.status = __cpu_to_virtio16(virtio_legacy_is_little_endian(),1412					      VIRTIO_NET_S_LINK_UP);1413	mlxbf_tmfifo_get_cfg_mac(net_config.mac);1414	rc = mlxbf_tmfifo_create_vdev(dev, fifo, VIRTIO_ID_NET,1415				      MLXBF_TMFIFO_NET_FEATURES, &net_config,1416				      sizeof(net_config));1417	if (rc)1418		goto fail;1419 1420	mod_timer(&fifo->timer, jiffies + MLXBF_TMFIFO_TIMER_INTERVAL);1421 1422	/* Make all updates visible before setting the 'is_ready' flag. */1423	virtio_mb(false);1424 1425	fifo->is_ready = true;1426	return 0;1427 1428fail:1429	mlxbf_tmfifo_cleanup(fifo);1430	return rc;1431}1432 1433/* Device remove function. */1434static void mlxbf_tmfifo_remove(struct platform_device *pdev)1435{1436	struct mlxbf_tmfifo *fifo = platform_get_drvdata(pdev);1437 1438	mlxbf_tmfifo_cleanup(fifo);1439}1440 1441static const struct acpi_device_id mlxbf_tmfifo_acpi_match[] = {1442	{ "MLNXBF01", 0 },1443	{}1444};1445MODULE_DEVICE_TABLE(acpi, mlxbf_tmfifo_acpi_match);1446 1447static struct platform_driver mlxbf_tmfifo_driver = {1448	.probe = mlxbf_tmfifo_probe,1449	.remove_new = mlxbf_tmfifo_remove,1450	.driver = {1451		.name = "bf-tmfifo",1452		.acpi_match_table = mlxbf_tmfifo_acpi_match,1453	},1454};1455 1456module_platform_driver(mlxbf_tmfifo_driver);1457 1458MODULE_DESCRIPTION("Mellanox BlueField SoC TmFifo Driver");1459MODULE_LICENSE("GPL v2");1460MODULE_AUTHOR("Mellanox Technologies");1461