lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite for Android: free password hash cracker in your pocket
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date:   Mon, 28 Jan 2019 12:28:06 -0500
From:   Liming Sun <lsun@...lanox.com>
To:     Rob Herring <robh+dt@...nel.org>,
        Mark Rutland <mark.rutland@....com>,
        Arnd Bergmann <arnd@...db.de>,
        David Woods <dwoods@...lanox.com>,
        Andy Shevchenko <andy@...radead.org>,
        Darren Hart <dvhart@...radead.org>,
        Vadim Pasternak <vadimp@...lanox.com>
Cc:     Liming Sun <lsun@...lanox.com>, devicetree@...r.kernel.org,
        linux-kernel@...r.kernel.org, platform-driver-x86@...r.kernel.org
Subject: [PATCH v8 1/2] platform/mellanox: Add TmFifo driver for Mellanox BlueField Soc

This commit adds the TmFifo platform driver for Mellanox BlueField
Soc. TmFifo is a shared FIFO which enables external host machine
to exchange data with the SoC via USB or PCIe. The driver is based
on virtio framework and has console and network access enabled.

Reviewed-by: David Woods <dwoods@...lanox.com>
Signed-off-by: Liming Sun <lsun@...lanox.com>
---
 drivers/platform/mellanox/Kconfig             |   13 +-
 drivers/platform/mellanox/Makefile            |    1 +
 drivers/platform/mellanox/mlxbf-tmfifo-regs.h |   67 ++
 drivers/platform/mellanox/mlxbf-tmfifo.c      | 1289 +++++++++++++++++++++++++
 4 files changed, 1369 insertions(+), 1 deletion(-)
 create mode 100644 drivers/platform/mellanox/mlxbf-tmfifo-regs.h
 create mode 100644 drivers/platform/mellanox/mlxbf-tmfifo.c

diff --git a/drivers/platform/mellanox/Kconfig b/drivers/platform/mellanox/Kconfig
index cd8a908..a565070 100644
--- a/drivers/platform/mellanox/Kconfig
+++ b/drivers/platform/mellanox/Kconfig
@@ -5,7 +5,7 @@
 
 menuconfig MELLANOX_PLATFORM
 	bool "Platform support for Mellanox hardware"
-	depends on X86 || ARM || COMPILE_TEST
+	depends on X86 || ARM || ARM64 || COMPILE_TEST
 	---help---
 	  Say Y here to get to see options for platform support for
 	  Mellanox systems. This option alone does not add any kernel code.
@@ -34,4 +34,15 @@ config MLXREG_IO
 	  to system resets operation, system reset causes monitoring and some
 	  kinds of mux selection.
 
+config MLXBF_TMFIFO
+	tristate "Mellanox BlueField SoC TmFifo platform driver"
+	depends on ARM64
+	default m
+	select VIRTIO_CONSOLE
+	select VIRTIO_NET
+	help
+	  Say y here to enable TmFifo support. The TmFifo driver provides
+          platform driver support for the TmFifo which supports console
+          and networking based on the virtio framework.
+
 endif # MELLANOX_PLATFORM
diff --git a/drivers/platform/mellanox/Makefile b/drivers/platform/mellanox/Makefile
index 57074d9c..f0c061d 100644
--- a/drivers/platform/mellanox/Makefile
+++ b/drivers/platform/mellanox/Makefile
@@ -5,3 +5,4 @@
 #
 obj-$(CONFIG_MLXREG_HOTPLUG)	+= mlxreg-hotplug.o
 obj-$(CONFIG_MLXREG_IO) += mlxreg-io.o
+obj-$(CONFIG_MLXBF_TMFIFO)	+= mlxbf-tmfifo.o
diff --git a/drivers/platform/mellanox/mlxbf-tmfifo-regs.h b/drivers/platform/mellanox/mlxbf-tmfifo-regs.h
new file mode 100644
index 0000000..90c9c2cf
--- /dev/null
+++ b/drivers/platform/mellanox/mlxbf-tmfifo-regs.h
@@ -0,0 +1,67 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2019, Mellanox Technologies. All rights reserved.
+ */
+
+#ifndef __MLXBF_TMFIFO_REGS_H__
+#define __MLXBF_TMFIFO_REGS_H__
+
+#include <linux/types.h>
+
+#define MLXBF_TMFIFO_TX_DATA 0x0
+
+#define MLXBF_TMFIFO_TX_STS 0x8
+#define MLXBF_TMFIFO_TX_STS__LENGTH 0x0001
+#define MLXBF_TMFIFO_TX_STS__COUNT_SHIFT 0
+#define MLXBF_TMFIFO_TX_STS__COUNT_WIDTH 9
+#define MLXBF_TMFIFO_TX_STS__COUNT_RESET_VAL 0
+#define MLXBF_TMFIFO_TX_STS__COUNT_RMASK 0x1ff
+#define MLXBF_TMFIFO_TX_STS__COUNT_MASK  0x1ff
+
+#define MLXBF_TMFIFO_TX_CTL 0x10
+#define MLXBF_TMFIFO_TX_CTL__LENGTH 0x0001
+#define MLXBF_TMFIFO_TX_CTL__LWM_SHIFT 0
+#define MLXBF_TMFIFO_TX_CTL__LWM_WIDTH 8
+#define MLXBF_TMFIFO_TX_CTL__LWM_RESET_VAL 128
+#define MLXBF_TMFIFO_TX_CTL__LWM_RMASK 0xff
+#define MLXBF_TMFIFO_TX_CTL__LWM_MASK  0xff
+#define MLXBF_TMFIFO_TX_CTL__HWM_SHIFT 8
+#define MLXBF_TMFIFO_TX_CTL__HWM_WIDTH 8
+#define MLXBF_TMFIFO_TX_CTL__HWM_RESET_VAL 128
+#define MLXBF_TMFIFO_TX_CTL__HWM_RMASK 0xff
+#define MLXBF_TMFIFO_TX_CTL__HWM_MASK  0xff00
+#define MLXBF_TMFIFO_TX_CTL__MAX_ENTRIES_SHIFT 32
+#define MLXBF_TMFIFO_TX_CTL__MAX_ENTRIES_WIDTH 9
+#define MLXBF_TMFIFO_TX_CTL__MAX_ENTRIES_RESET_VAL 256
+#define MLXBF_TMFIFO_TX_CTL__MAX_ENTRIES_RMASK 0x1ff
+#define MLXBF_TMFIFO_TX_CTL__MAX_ENTRIES_MASK  0x1ff00000000ULL
+
+#define MLXBF_TMFIFO_RX_DATA 0x0
+
+#define MLXBF_TMFIFO_RX_STS 0x8
+#define MLXBF_TMFIFO_RX_STS__LENGTH 0x0001
+#define MLXBF_TMFIFO_RX_STS__COUNT_SHIFT 0
+#define MLXBF_TMFIFO_RX_STS__COUNT_WIDTH 9
+#define MLXBF_TMFIFO_RX_STS__COUNT_RESET_VAL 0
+#define MLXBF_TMFIFO_RX_STS__COUNT_RMASK 0x1ff
+#define MLXBF_TMFIFO_RX_STS__COUNT_MASK  0x1ff
+
+#define MLXBF_TMFIFO_RX_CTL 0x10
+#define MLXBF_TMFIFO_RX_CTL__LENGTH 0x0001
+#define MLXBF_TMFIFO_RX_CTL__LWM_SHIFT 0
+#define MLXBF_TMFIFO_RX_CTL__LWM_WIDTH 8
+#define MLXBF_TMFIFO_RX_CTL__LWM_RESET_VAL 128
+#define MLXBF_TMFIFO_RX_CTL__LWM_RMASK 0xff
+#define MLXBF_TMFIFO_RX_CTL__LWM_MASK  0xff
+#define MLXBF_TMFIFO_RX_CTL__HWM_SHIFT 8
+#define MLXBF_TMFIFO_RX_CTL__HWM_WIDTH 8
+#define MLXBF_TMFIFO_RX_CTL__HWM_RESET_VAL 128
+#define MLXBF_TMFIFO_RX_CTL__HWM_RMASK 0xff
+#define MLXBF_TMFIFO_RX_CTL__HWM_MASK  0xff00
+#define MLXBF_TMFIFO_RX_CTL__MAX_ENTRIES_SHIFT 32
+#define MLXBF_TMFIFO_RX_CTL__MAX_ENTRIES_WIDTH 9
+#define MLXBF_TMFIFO_RX_CTL__MAX_ENTRIES_RESET_VAL 256
+#define MLXBF_TMFIFO_RX_CTL__MAX_ENTRIES_RMASK 0x1ff
+#define MLXBF_TMFIFO_RX_CTL__MAX_ENTRIES_MASK  0x1ff00000000ULL
+
+#endif /* !defined(__MLXBF_TMFIFO_REGS_H__) */
diff --git a/drivers/platform/mellanox/mlxbf-tmfifo.c b/drivers/platform/mellanox/mlxbf-tmfifo.c
new file mode 100644
index 0000000..c1afe47
--- /dev/null
+++ b/drivers/platform/mellanox/mlxbf-tmfifo.c
@@ -0,0 +1,1289 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Mellanox BlueField SoC TmFifo driver
+ *
+ * Copyright (C) 2019 Mellanox Technologies
+ */
+
+#include <linux/acpi.h>
+#include <linux/bitfield.h>
+#include <linux/cache.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/efi.h>
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/math64.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.h>
+#include <linux/resource.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/version.h>
+#include <linux/virtio.h>
+#include <linux/virtio_config.h>
+#include <linux/virtio_console.h>
+#include <linux/virtio_ids.h>
+#include <linux/virtio_net.h>
+#include <linux/virtio_ring.h>
+#include <asm/byteorder.h>
+
+#include "mlxbf-tmfifo-regs.h"
+
+/* Vring size. */
+#define MLXBF_TMFIFO_VRING_SIZE			1024
+
+/* Console Tx buffer size. */
+#define MLXBF_TMFIFO_CONS_TX_BUF_SIZE		(32 * 1024)
+
+/* House-keeping timer interval. */
+static int mlxbf_tmfifo_timer_interval = HZ / 10;
+
+/* Global lock. */
+static DEFINE_MUTEX(mlxbf_tmfifo_lock);
+
+/* Virtual devices sharing the TM FIFO. */
+#define MLXBF_TMFIFO_VDEV_MAX		(VIRTIO_ID_CONSOLE + 1)
+
+/* Struct declaration. */
+struct mlxbf_tmfifo;
+
+/* Structure to maintain the ring state. */
+struct mlxbf_tmfifo_vring {
+	void *va;			/* virtual address */
+	dma_addr_t dma;			/* dma address */
+	struct virtqueue *vq;		/* virtqueue pointer */
+	struct vring_desc *desc;	/* current desc */
+	struct vring_desc *desc_head;	/* current desc head */
+	int cur_len;			/* processed len in current desc */
+	int rem_len;			/* remaining length to be processed */
+	int size;			/* vring size */
+	int align;			/* vring alignment */
+	int id;				/* vring id */
+	int vdev_id;			/* TMFIFO_VDEV_xxx */
+	u32 pkt_len;			/* packet total length */
+	__virtio16 next_avail;		/* next avail desc id */
+	struct mlxbf_tmfifo *fifo;	/* pointer back to the tmfifo */
+};
+
+/* Interrupt types. */
+enum {
+	MLXBF_TM_RX_LWM_IRQ,		/* Rx low water mark irq */
+	MLXBF_TM_RX_HWM_IRQ,		/* Rx high water mark irq */
+	MLXBF_TM_TX_LWM_IRQ,		/* Tx low water mark irq */
+	MLXBF_TM_TX_HWM_IRQ,		/* Tx high water mark irq */
+	MLXBF_TM_IRQ_CNT
+};
+
+/* Ring types (Rx & Tx). */
+enum {
+	MLXBF_TMFIFO_VRING_RX,		/* Rx ring */
+	MLXBF_TMFIFO_VRING_TX,		/* Tx ring */
+	MLXBF_TMFIFO_VRING_NUM
+};
+
+struct mlxbf_tmfifo_vdev {
+	struct virtio_device vdev;	/* virtual device */
+	u8 status;
+	u64 features;
+	union {				/* virtio config space */
+		struct virtio_console_config cons;
+		struct virtio_net_config net;
+	} config;
+	struct mlxbf_tmfifo_vring vrings[MLXBF_TMFIFO_VRING_NUM];
+	u8 *tx_buf;			/* tx buffer */
+	u32 tx_head;			/* tx buffer head */
+	u32 tx_tail;			/* tx buffer tail */
+};
+
+struct mlxbf_tmfifo_irq_info {
+	struct mlxbf_tmfifo *fifo;	/* tmfifo structure */
+	int irq;			/* interrupt number */
+	int index;			/* array index */
+};
+
+/* TMFIFO device structure */
+struct mlxbf_tmfifo {
+	struct mlxbf_tmfifo_vdev *vdev[MLXBF_TMFIFO_VDEV_MAX]; /* devices */
+	struct platform_device *pdev;	/* platform device */
+	struct mutex lock;		/* fifo lock */
+	void __iomem *rx_base;		/* mapped register base */
+	void __iomem *tx_base;		/* mapped register base */
+	int tx_fifo_size;		/* number of entries of the Tx FIFO */
+	int rx_fifo_size;		/* number of entries of the Rx FIFO */
+	unsigned long pend_events;	/* pending bits for deferred process */
+	struct mlxbf_tmfifo_irq_info irq_info[MLXBF_TM_IRQ_CNT]; /* irq info */
+	struct work_struct work;	/* work struct for deferred process */
+	struct timer_list timer;	/* keepalive timer */
+	struct mlxbf_tmfifo_vring *vring[2];	/* current Tx/Rx ring */
+	bool is_ready;			/* ready flag */
+	spinlock_t spin_lock;		/* spin lock */
+};
+
+union mlxbf_tmfifo_msg_hdr {
+	struct {
+		u8 type;		/* message type */
+		__be16 len;		/* payload length */
+		u8 unused[5];		/* reserved, set to 0 */
+	} __packed;
+	u64 data;
+};
+
+/*
+ * Default MAC.
+ * This MAC address will be read from EFI persistent variable if configured.
+ * It can also be reconfigured with standard Linux tools.
+ */
+static u8 mlxbf_tmfifo_net_default_mac[6] = {
+	0x00, 0x1A, 0xCA, 0xFF, 0xFF, 0x01};
+
+/* MTU setting of the virtio-net interface. */
+#define MLXBF_TMFIFO_NET_MTU		1500
+
+/* Maximum L2 header length. */
+#define MLXBF_TMFIFO_NET_L2_OVERHEAD	36
+
+/* Supported virtio-net features. */
+#define MLXBF_TMFIFO_NET_FEATURES	((1UL << VIRTIO_NET_F_MTU) | \
+					 (1UL << VIRTIO_NET_F_STATUS) | \
+					 (1UL << VIRTIO_NET_F_MAC))
+
+/* Return the consumed Tx buffer space. */
+static int mlxbf_tmfifo_vdev_tx_buf_len(struct mlxbf_tmfifo_vdev *vdev)
+{
+	return ((vdev->tx_tail >= vdev->tx_head) ?
+	       (vdev->tx_tail - vdev->tx_head) :
+	       (MLXBF_TMFIFO_CONS_TX_BUF_SIZE - vdev->tx_head + vdev->tx_tail));
+}
+
+/* Return the available Tx buffer space. */
+static int mlxbf_tmfifo_vdev_tx_buf_avail(struct mlxbf_tmfifo_vdev *vdev)
+{
+	return (MLXBF_TMFIFO_CONS_TX_BUF_SIZE - 8 -
+		mlxbf_tmfifo_vdev_tx_buf_len(vdev));
+}
+
+/* Update Tx buffer pointer after pushing data. */
+static void mlxbf_tmfifo_vdev_tx_buf_push(struct mlxbf_tmfifo_vdev *vdev,
+					  u32 len)
+{
+	vdev->tx_tail += len;
+	if (vdev->tx_tail >= MLXBF_TMFIFO_CONS_TX_BUF_SIZE)
+		vdev->tx_tail -= MLXBF_TMFIFO_CONS_TX_BUF_SIZE;
+}
+
+/* Update Tx buffer pointer after popping data. */
+static void mlxbf_tmfifo_vdev_tx_buf_pop(struct mlxbf_tmfifo_vdev *vdev,
+					 u32 len)
+{
+	vdev->tx_head += len;
+	if (vdev->tx_head >= MLXBF_TMFIFO_CONS_TX_BUF_SIZE)
+		vdev->tx_head -= MLXBF_TMFIFO_CONS_TX_BUF_SIZE;
+}
+
+/* Allocate vrings for the fifo. */
+static int mlxbf_tmfifo_alloc_vrings(struct mlxbf_tmfifo *fifo,
+				     struct mlxbf_tmfifo_vdev *tm_vdev,
+				     int vdev_id)
+{
+	struct mlxbf_tmfifo_vring *vring;
+	dma_addr_t dma;
+	int i, size;
+	void *va;
+
+	for (i = 0; i < ARRAY_SIZE(tm_vdev->vrings); i++) {
+		vring = &tm_vdev->vrings[i];
+		vring->fifo = fifo;
+		vring->size = MLXBF_TMFIFO_VRING_SIZE;
+		vring->align = SMP_CACHE_BYTES;
+		vring->id = i;
+		vring->vdev_id = vdev_id;
+
+		size = PAGE_ALIGN(vring_size(vring->size, vring->align));
+		va = dma_alloc_coherent(tm_vdev->vdev.dev.parent, size, &dma,
+					GFP_KERNEL);
+		if (!va) {
+			dev_err(tm_vdev->vdev.dev.parent,
+				"vring allocation failed\n");
+			return -EINVAL;
+		}
+
+		vring->va = va;
+		vring->dma = dma;
+	}
+
+	return 0;
+}
+
+/* Free vrings of the fifo device. */
+static void mlxbf_tmfifo_free_vrings(struct mlxbf_tmfifo *fifo, int vdev_id)
+{
+	struct mlxbf_tmfifo_vdev *tm_vdev = fifo->vdev[vdev_id];
+	struct mlxbf_tmfifo_vring *vring;
+	int i, size;
+
+	for (i = 0; i < ARRAY_SIZE(tm_vdev->vrings); i++) {
+		vring = &tm_vdev->vrings[i];
+
+		size = PAGE_ALIGN(vring_size(vring->size, vring->align));
+		if (vring->va) {
+			dma_free_coherent(tm_vdev->vdev.dev.parent, size,
+					  vring->va, vring->dma);
+			vring->va = NULL;
+			if (vring->vq) {
+				vring_del_virtqueue(vring->vq);
+				vring->vq = NULL;
+			}
+		}
+	}
+}
+
+/* Free interrupts of the fifo device. */
+static void mlxbf_tmfifo_free_irqs(struct mlxbf_tmfifo *fifo)
+{
+	int i, irq;
+
+	for (i = 0; i < MLXBF_TM_IRQ_CNT; i++) {
+		irq = fifo->irq_info[i].irq;
+		if (irq) {
+			fifo->irq_info[i].irq = 0;
+			disable_irq(irq);
+			free_irq(irq, (u8 *)fifo + i);
+		}
+	}
+}
+
+/* Interrupt handler. */
+static irqreturn_t mlxbf_tmfifo_irq_handler(int irq, void *arg)
+{
+	struct mlxbf_tmfifo_irq_info *irq_info;
+
+	irq_info = (struct mlxbf_tmfifo_irq_info *)arg;
+
+	if (irq_info->index < MLXBF_TM_IRQ_CNT &&
+	    !test_and_set_bit(irq_info->index, &irq_info->fifo->pend_events))
+		schedule_work(&irq_info->fifo->work);
+
+	return IRQ_HANDLED;
+}
+
+/* Nothing to do for now. */
+static void mlxbf_tmfifo_virtio_dev_release(struct device *dev)
+{
+}
+
+/* Get the next packet descriptor from the vring. */
+static inline struct vring_desc *
+mlxbf_tmfifo_virtio_get_next_desc(struct virtqueue *vq)
+{
+	struct mlxbf_tmfifo_vring *vring;
+	unsigned int idx, head;
+	struct vring *vr;
+
+	vring = (struct mlxbf_tmfifo_vring *)vq->priv;
+	vr = (struct vring *)virtqueue_get_vring(vq);
+
+	if (!vr || vring->next_avail == vr->avail->idx)
+		return NULL;
+
+	idx = vring->next_avail % vr->num;
+	head = vr->avail->ring[idx];
+	BUG_ON(head >= vr->num);
+	vring->next_avail++;
+	return &vr->desc[head];
+}
+
+static inline void mlxbf_tmfifo_virtio_release_desc(
+	struct virtio_device *vdev, struct vring *vr,
+	struct vring_desc *desc, u32 len)
+{
+	unsigned int idx;
+
+	idx = vr->used->idx % vr->num;
+	vr->used->ring[idx].id = desc - vr->desc;
+	vr->used->ring[idx].len = cpu_to_virtio32(vdev, len);
+
+	/* Virtio could poll and check the 'idx' to decide
+	 * whether the desc is done or not. Add a memory
+	 * barrier here to make sure the update above completes
+	 * before updating the idx.
+	 */
+	mb();
+	vr->used->idx++;
+}
+
+/* Get the total length of a descriptor chain. */
+static inline u32 mlxbf_tmfifo_virtio_get_pkt_len(struct virtio_device *vdev,
+						  struct vring_desc *desc,
+						  struct vring *vr)
+{
+	u32 len = 0, idx;
+
+	while (desc) {
+		len += virtio32_to_cpu(vdev, desc->len);
+		if (!(virtio16_to_cpu(vdev, desc->flags) & VRING_DESC_F_NEXT))
+			break;
+		idx = virtio16_to_cpu(vdev, desc->next);
+		desc = &vr->desc[idx];
+	}
+
+	return len;
+}
+
+static void mlxbf_tmfifo_release_pkt(struct virtio_device *vdev,
+				     struct mlxbf_tmfifo_vring *vring,
+				     struct vring_desc **desc)
+{
+	struct vring *vr = (struct vring *)virtqueue_get_vring(vring->vq);
+	struct vring_desc *desc_head;
+	uint32_t pkt_len = 0;
+
+	if (!vr)
+		return;
+
+	if (desc != NULL && *desc != NULL && vring->desc_head != NULL) {
+		desc_head = vring->desc_head;
+		pkt_len = vring->pkt_len;
+	} else {
+		desc_head = mlxbf_tmfifo_virtio_get_next_desc(vring->vq);
+		if (desc_head != NULL) {
+			pkt_len = mlxbf_tmfifo_virtio_get_pkt_len(
+				vdev, desc_head, vr);
+		}
+	}
+
+	if (desc_head != NULL)
+		mlxbf_tmfifo_virtio_release_desc(vdev, vr, desc_head, pkt_len);
+
+	if (desc != NULL)
+		*desc = NULL;
+	vring->pkt_len = 0;
+}
+
+/* House-keeping timer. */
+static void mlxbf_tmfifo_timer(struct timer_list *arg)
+{
+	struct mlxbf_tmfifo *fifo;
+
+	fifo = container_of(arg, struct mlxbf_tmfifo, timer);
+
+	/*
+	 * Wake up the work handler to poll the Rx FIFO in case interrupt
+	 * missing or any leftover bytes stuck in the FIFO.
+	 */
+	test_and_set_bit(MLXBF_TM_RX_HWM_IRQ, &fifo->pend_events);
+
+	/*
+	 * Wake up Tx handler in case virtio has queued too many packets
+	 * and are waiting for buffer return.
+	 */
+	test_and_set_bit(MLXBF_TM_TX_LWM_IRQ, &fifo->pend_events);
+
+	schedule_work(&fifo->work);
+
+	mod_timer(&fifo->timer, jiffies + mlxbf_tmfifo_timer_interval);
+}
+
+/* Buffer the console output. */
+static void mlxbf_tmfifo_console_output(struct mlxbf_tmfifo_vdev *cons,
+					struct virtqueue *vq)
+{
+	struct vring *vr = (struct vring *)virtqueue_get_vring(vq);
+	struct vring_desc *head_desc, *desc = NULL;
+	struct virtio_device *vdev = &cons->vdev;
+	u32 len, pkt_len, idx;
+	void *addr;
+
+	for (;;) {
+		head_desc = mlxbf_tmfifo_virtio_get_next_desc(vq);
+		if (head_desc == NULL)
+			break;
+
+		/* Release the packet if no more space. */
+		pkt_len = mlxbf_tmfifo_virtio_get_pkt_len(vdev, head_desc, vr);
+		if (pkt_len > mlxbf_tmfifo_vdev_tx_buf_avail(cons)) {
+			mlxbf_tmfifo_virtio_release_desc(vdev, vr, head_desc,
+							 pkt_len);
+			break;
+		}
+
+		desc = head_desc;
+
+		while (desc != NULL) {
+			addr = phys_to_virt(virtio64_to_cpu(vdev, desc->addr));
+			len = virtio32_to_cpu(vdev, desc->len);
+
+			if (len <= MLXBF_TMFIFO_CONS_TX_BUF_SIZE -
+			    cons->tx_tail) {
+				memcpy(cons->tx_buf + cons->tx_tail, addr, len);
+			} else {
+				u32 seg;
+
+				seg = MLXBF_TMFIFO_CONS_TX_BUF_SIZE -
+					cons->tx_tail;
+				memcpy(cons->tx_buf + cons->tx_tail, addr, seg);
+				addr += seg;
+				memcpy(cons->tx_buf, addr, len - seg);
+			}
+			mlxbf_tmfifo_vdev_tx_buf_push(cons, len);
+
+			if (!(virtio16_to_cpu(vdev, desc->flags) &
+			    VRING_DESC_F_NEXT))
+				break;
+			idx = virtio16_to_cpu(vdev, desc->next);
+			desc = &vr->desc[idx];
+		}
+
+		mlxbf_tmfifo_virtio_release_desc(vdev, vr, head_desc, pkt_len);
+	}
+}
+
+/* Rx & Tx processing of a virtual queue. */
+static void mlxbf_tmfifo_virtio_rxtx(struct virtqueue *vq, bool is_rx)
+{
+	int num_avail = 0, hdr_len, tx_reserve;
+	struct mlxbf_tmfifo_vring *vring;
+	struct mlxbf_tmfifo_vdev *cons;
+	struct virtio_device *vdev;
+	struct mlxbf_tmfifo *fifo;
+	struct vring_desc *desc;
+	unsigned long flags;
+	struct vring *vr;
+	u64 sts, data;
+	u32 len, idx;
+	void *addr;
+
+	if (!vq)
+		return;
+
+	vring = (struct mlxbf_tmfifo_vring *)vq->priv;
+	fifo = vring->fifo;
+	vr = (struct vring *)virtqueue_get_vring(vq);
+
+	if (!fifo->vdev[vring->vdev_id])
+		return;
+	vdev = &fifo->vdev[vring->vdev_id]->vdev;
+	cons = fifo->vdev[VIRTIO_ID_CONSOLE];
+
+	/* Don't continue if another vring is running. */
+	if (fifo->vring[is_rx] != NULL && fifo->vring[is_rx] != vring)
+		return;
+
+	/* tx_reserve is used to reserved some room in FIFO for console. */
+	if (vring->vdev_id == VIRTIO_ID_NET) {
+		hdr_len = sizeof(struct virtio_net_hdr);
+		tx_reserve = fifo->tx_fifo_size / 16;
+	} else {
+		BUG_ON(vring->vdev_id != VIRTIO_ID_CONSOLE);
+		hdr_len = 0;
+		tx_reserve = 1;
+	}
+
+	desc = vring->desc;
+
+	while (1) {
+		/* Get available FIFO space. */
+		if (num_avail == 0) {
+			if (is_rx) {
+				/* Get the number of available words in FIFO. */
+				sts = readq(fifo->rx_base +
+					    MLXBF_TMFIFO_RX_STS);
+				num_avail = FIELD_GET(
+					MLXBF_TMFIFO_RX_STS__COUNT_MASK, sts);
+
+				/* Don't continue if nothing in FIFO. */
+				if (num_avail <= 0)
+					break;
+			} else {
+				/* Get available space in FIFO. */
+				sts = readq(fifo->tx_base +
+					    MLXBF_TMFIFO_TX_STS);
+				num_avail = fifo->tx_fifo_size - tx_reserve -
+					FIELD_GET(
+						MLXBF_TMFIFO_TX_STS__COUNT_MASK,
+						sts);
+
+				if (num_avail <= 0)
+					break;
+			}
+		}
+
+		/* Console output always comes from the Tx buffer. */
+		if (!is_rx && vring->vdev_id == VIRTIO_ID_CONSOLE &&
+		    cons != NULL && cons->tx_buf != NULL) {
+			union mlxbf_tmfifo_msg_hdr hdr;
+			int size;
+
+			size = mlxbf_tmfifo_vdev_tx_buf_len(cons);
+			if (num_avail < 2 || size == 0)
+				return;
+			if (size + sizeof(hdr) > num_avail * sizeof(u64))
+				size = num_avail * sizeof(u64) - sizeof(hdr);
+			/* Write header. */
+			hdr.data = 0;
+			hdr.type = VIRTIO_ID_CONSOLE;
+			hdr.len = htons(size);
+			writeq(cpu_to_le64(hdr.data),
+			       fifo->tx_base + MLXBF_TMFIFO_TX_DATA);
+
+			spin_lock_irqsave(&fifo->spin_lock, flags);
+			while (size > 0) {
+				addr = cons->tx_buf + cons->tx_head;
+
+				if (cons->tx_head + sizeof(u64) <=
+				    MLXBF_TMFIFO_CONS_TX_BUF_SIZE) {
+					memcpy(&data, addr, sizeof(u64));
+				} else {
+					int partial;
+
+					partial =
+						MLXBF_TMFIFO_CONS_TX_BUF_SIZE -
+						cons->tx_head;
+
+					memcpy(&data, addr, partial);
+					memcpy((u8 *)&data + partial,
+					       cons->tx_buf,
+					       sizeof(u64) - partial);
+				}
+				writeq(data,
+				       fifo->tx_base + MLXBF_TMFIFO_TX_DATA);
+
+				if (size >= sizeof(u64)) {
+					mlxbf_tmfifo_vdev_tx_buf_pop(
+						cons, sizeof(u64));
+					size -= sizeof(u64);
+				} else {
+					mlxbf_tmfifo_vdev_tx_buf_pop(
+						cons, size);
+					size = 0;
+				}
+			}
+			spin_unlock_irqrestore(&fifo->spin_lock, flags);
+			return;
+		}
+
+		/* Get the desc of next packet. */
+		if (!desc) {
+			/* Save the head desc of the chain. */
+			vring->desc_head =
+				mlxbf_tmfifo_virtio_get_next_desc(vq);
+			if (!vring->desc_head) {
+				vring->desc = NULL;
+				return;
+			}
+			desc = vring->desc_head;
+			vring->desc = desc;
+
+			if (is_rx && vring->vdev_id == VIRTIO_ID_NET) {
+				struct virtio_net_hdr *net_hdr;
+
+				/* Initialize the packet header. */
+				net_hdr = (struct virtio_net_hdr *)
+					phys_to_virt(virtio64_to_cpu(
+						vdev, desc->addr));
+				memset(net_hdr, 0, sizeof(*net_hdr));
+			}
+		}
+
+		/* Beginning of each packet. */
+		if (vring->pkt_len == 0) {
+			int vdev_id, vring_change = 0;
+			union mlxbf_tmfifo_msg_hdr hdr;
+
+			num_avail--;
+
+			/* Read/Write packet length. */
+			if (is_rx) {
+				hdr.data = readq(fifo->rx_base +
+						 MLXBF_TMFIFO_RX_DATA);
+				hdr.data = le64_to_cpu(hdr.data);
+
+				/* Skip the length 0 packet (keepalive). */
+				if (hdr.len == 0)
+					continue;
+
+				/* Check packet type. */
+				if (hdr.type == VIRTIO_ID_NET) {
+					struct virtio_net_config *config;
+
+					vdev_id = VIRTIO_ID_NET;
+					hdr_len = sizeof(struct virtio_net_hdr);
+					config =
+					    &fifo->vdev[vdev_id]->config.net;
+					if (ntohs(hdr.len) > config->mtu +
+						MLXBF_TMFIFO_NET_L2_OVERHEAD)
+						continue;
+				} else if (hdr.type == VIRTIO_ID_CONSOLE) {
+					vdev_id = VIRTIO_ID_CONSOLE;
+					hdr_len = 0;
+				} else {
+					continue;
+				}
+
+				/*
+				 * Check whether the new packet still belongs
+				 * to this vring or not. If not, update the
+				 * pkt_len of the new vring and return.
+				 */
+				if (vdev_id != vring->vdev_id) {
+					struct mlxbf_tmfifo_vdev *dev2 =
+						fifo->vdev[vdev_id];
+
+					if (!dev2)
+						break;
+					vring->desc = desc;
+					vring =
+					  &dev2->vrings[MLXBF_TMFIFO_VRING_RX];
+					vring_change = 1;
+				}
+				vring->pkt_len = ntohs(hdr.len) + hdr_len;
+			} else {
+				vring->pkt_len =
+					mlxbf_tmfifo_virtio_get_pkt_len(
+						vdev, desc, vr);
+
+				hdr.data = 0;
+				hdr.type = (vring->vdev_id == VIRTIO_ID_NET) ?
+					VIRTIO_ID_NET :
+					VIRTIO_ID_CONSOLE;
+				hdr.len = htons(vring->pkt_len - hdr_len);
+				writeq(cpu_to_le64(hdr.data),
+				       fifo->tx_base + MLXBF_TMFIFO_TX_DATA);
+			}
+
+			vring->cur_len = hdr_len;
+			vring->rem_len = vring->pkt_len;
+			fifo->vring[is_rx] = vring;
+
+			if (vring_change)
+				return;
+			continue;
+		}
+
+		/* Check available space in this desc. */
+		len = virtio32_to_cpu(vdev, desc->len);
+		if (len > vring->rem_len)
+			len = vring->rem_len;
+
+		/* Check if the current desc is already done. */
+		if (vring->cur_len == len)
+			goto check_done;
+
+		addr = phys_to_virt(virtio64_to_cpu(vdev, desc->addr));
+
+		/* Read a word from FIFO for Rx. */
+		if (is_rx) {
+			data = readq(fifo->rx_base + MLXBF_TMFIFO_RX_DATA);
+			data = le64_to_cpu(data);
+		}
+
+		if (vring->cur_len + sizeof(u64) <= len) {
+			/* The whole word. */
+			if (is_rx) {
+				memcpy(addr + vring->cur_len, &data,
+				       sizeof(u64));
+			} else {
+				memcpy(&data, addr + vring->cur_len,
+				       sizeof(u64));
+			}
+			vring->cur_len += sizeof(u64);
+		} else {
+			/* Leftover bytes. */
+			BUG_ON(vring->cur_len > len);
+			if (is_rx) {
+				memcpy(addr + vring->cur_len, &data,
+				       len - vring->cur_len);
+			} else {
+				memcpy(&data, addr + vring->cur_len,
+				       len - vring->cur_len);
+			}
+			vring->cur_len = len;
+		}
+
+		/* Write the word into FIFO for Tx. */
+		if (!is_rx) {
+			writeq(cpu_to_le64(data),
+			       fifo->tx_base + MLXBF_TMFIFO_TX_DATA);
+		}
+
+		num_avail--;
+
+check_done:
+		/* Check whether this desc is full or completed. */
+		if (vring->cur_len == len) {
+			vring->cur_len = 0;
+			vring->rem_len -= len;
+
+			/* Get the next desc on the chain. */
+			if (vring->rem_len > 0 &&
+			    (virtio16_to_cpu(vdev, desc->flags) &
+						VRING_DESC_F_NEXT)) {
+				idx = virtio16_to_cpu(vdev, desc->next);
+				desc = &vr->desc[idx];
+				continue;
+			}
+
+			/* Done and release the desc. */
+			mlxbf_tmfifo_release_pkt(vdev, vring, &desc);
+			fifo->vring[is_rx] = NULL;
+
+			/* Notify upper layer that packet is done. */
+			spin_lock_irqsave(&fifo->spin_lock, flags);
+			vring_interrupt(0, vq);
+			spin_unlock_irqrestore(&fifo->spin_lock, flags);
+			continue;
+		}
+	}
+
+	/* Save the current desc. */
+	vring->desc = desc;
+}
+
+/* The notify function is called when new buffers are posted. */
+static bool mlxbf_tmfifo_virtio_notify(struct virtqueue *vq)
+{
+	struct mlxbf_tmfifo_vring *vring;
+	struct mlxbf_tmfifo *fifo;
+	unsigned long flags;
+
+	vring = (struct mlxbf_tmfifo_vring *)vq->priv;
+	fifo = vring->fifo;
+
+	/*
+	 * Virtio maintains vrings in pairs, even number ring for Rx
+	 * and odd number ring for Tx.
+	 */
+	if (!(vring->id & 1)) {
+		/* Set the RX HWM bit to start Rx. */
+		if (!test_and_set_bit(MLXBF_TM_RX_HWM_IRQ, &fifo->pend_events))
+			schedule_work(&fifo->work);
+	} else {
+		/*
+		 * Console could make blocking call with interrupts disabled.
+		 * In such case, the vring needs to be served right away. For
+		 * other cases, just set the TX LWM bit to start Tx in the
+		 * worker handler.
+		 */
+		if (vring->vdev_id == VIRTIO_ID_CONSOLE) {
+			spin_lock_irqsave(&fifo->spin_lock, flags);
+			mlxbf_tmfifo_console_output(
+				fifo->vdev[VIRTIO_ID_CONSOLE], vq);
+			spin_unlock_irqrestore(&fifo->spin_lock, flags);
+			schedule_work(&fifo->work);
+		} else if (!test_and_set_bit(MLXBF_TM_TX_LWM_IRQ,
+					     &fifo->pend_events))
+			schedule_work(&fifo->work);
+	}
+
+	return true;
+}
+
+/* Work handler for Rx and Tx case. */
+static void mlxbf_tmfifo_work_handler(struct work_struct *work)
+{
+	struct mlxbf_tmfifo_vdev *tm_vdev;
+	struct mlxbf_tmfifo *fifo;
+	int i;
+
+	fifo = container_of(work, struct mlxbf_tmfifo, work);
+	if (!fifo->is_ready)
+		return;
+
+	mutex_lock(&fifo->lock);
+
+	/* Tx (Send data to the TmFifo). */
+	if (test_and_clear_bit(MLXBF_TM_TX_LWM_IRQ, &fifo->pend_events) &&
+		       fifo->irq_info[MLXBF_TM_TX_LWM_IRQ].irq) {
+		for (i = 0; i < MLXBF_TMFIFO_VDEV_MAX; i++) {
+			tm_vdev = fifo->vdev[i];
+			if (tm_vdev != NULL) {
+				mlxbf_tmfifo_virtio_rxtx(
+				    tm_vdev->vrings[MLXBF_TMFIFO_VRING_TX].vq,
+				    false);
+			}
+		}
+	}
+
+	/* Rx (Receive data from the TmFifo). */
+	if (test_and_clear_bit(MLXBF_TM_RX_HWM_IRQ, &fifo->pend_events) &&
+		       fifo->irq_info[MLXBF_TM_RX_HWM_IRQ].irq) {
+		for (i = 0; i < MLXBF_TMFIFO_VDEV_MAX; i++) {
+			tm_vdev = fifo->vdev[i];
+			if (tm_vdev != NULL) {
+				mlxbf_tmfifo_virtio_rxtx(
+				    tm_vdev->vrings[MLXBF_TMFIFO_VRING_RX].vq,
+				    true);
+			}
+		}
+	}
+
+	mutex_unlock(&fifo->lock);
+}
+
+/* Get the array of feature bits for this device. */
+static u64 mlxbf_tmfifo_virtio_get_features(struct virtio_device *vdev)
+{
+	struct mlxbf_tmfifo_vdev *tm_vdev;
+
+	tm_vdev = container_of(vdev, struct mlxbf_tmfifo_vdev, vdev);
+	return tm_vdev->features;
+}
+
+/* Confirm device features to use. */
+static int mlxbf_tmfifo_virtio_finalize_features(struct virtio_device *vdev)
+{
+	struct mlxbf_tmfifo_vdev *tm_vdev;
+
+	tm_vdev = container_of(vdev, struct mlxbf_tmfifo_vdev, vdev);
+	tm_vdev->features = vdev->features;
+
+	return 0;
+}
+
+/* Free virtqueues found by find_vqs(). */
+static void mlxbf_tmfifo_virtio_del_vqs(struct virtio_device *vdev)
+{
+	struct mlxbf_tmfifo_vdev *tm_vdev;
+	struct mlxbf_tmfifo_vring *vring;
+	struct virtqueue *vq;
+	int i;
+
+	tm_vdev = container_of(vdev, struct mlxbf_tmfifo_vdev, vdev);
+
+	for (i = 0; i < ARRAY_SIZE(tm_vdev->vrings); i++) {
+		vring = &tm_vdev->vrings[i];
+
+		/* Release the pending packet. */
+		if (vring->desc != NULL) {
+			mlxbf_tmfifo_release_pkt(&tm_vdev->vdev, vring,
+						 &vring->desc);
+		}
+
+		vq = vring->vq;
+		if (vq) {
+			vring->vq = NULL;
+			vring_del_virtqueue(vq);
+		}
+	}
+}
+
+/* Create and initialize the virtual queues. */
+static int mlxbf_tmfifo_virtio_find_vqs(struct virtio_device *vdev,
+					unsigned int nvqs,
+					struct virtqueue *vqs[],
+					vq_callback_t *callbacks[],
+					const char * const names[],
+					const bool *ctx,
+					struct irq_affinity *desc)
+{
+	struct mlxbf_tmfifo_vdev *tm_vdev;
+	struct mlxbf_tmfifo_vring *vring;
+	int i, ret = -EINVAL, size;
+	struct virtqueue *vq;
+
+	tm_vdev = container_of(vdev, struct mlxbf_tmfifo_vdev, vdev);
+	if (nvqs > ARRAY_SIZE(tm_vdev->vrings))
+		return -EINVAL;
+
+	for (i = 0; i < nvqs; ++i) {
+		if (!names[i])
+			goto error;
+		vring = &tm_vdev->vrings[i];
+
+		/* zero vring */
+		size = vring_size(vring->size, vring->align);
+		memset(vring->va, 0, size);
+		vq = vring_new_virtqueue(i, vring->size, vring->align, vdev,
+					 false, false, vring->va,
+					 mlxbf_tmfifo_virtio_notify,
+					 callbacks[i], names[i]);
+		if (!vq) {
+			dev_err(&vdev->dev, "vring_new_virtqueue failed\n");
+			ret = -ENOMEM;
+			goto error;
+		}
+
+		vqs[i] = vq;
+		vring->vq = vq;
+		vq->priv = vring;
+	}
+
+	return 0;
+
+error:
+	mlxbf_tmfifo_virtio_del_vqs(vdev);
+	return ret;
+}
+
+/* Read the status byte. */
+static u8 mlxbf_tmfifo_virtio_get_status(struct virtio_device *vdev)
+{
+	struct mlxbf_tmfifo_vdev *tm_vdev;
+
+	tm_vdev = container_of(vdev, struct mlxbf_tmfifo_vdev, vdev);
+
+	return tm_vdev->status;
+}
+
+/* Write the status byte. */
+static void mlxbf_tmfifo_virtio_set_status(struct virtio_device *vdev,
+					   u8 status)
+{
+	struct mlxbf_tmfifo_vdev *tm_vdev;
+
+	tm_vdev = container_of(vdev, struct mlxbf_tmfifo_vdev, vdev);
+	tm_vdev->status = status;
+}
+
+/* Reset the device. Not much here for now. */
+static void mlxbf_tmfifo_virtio_reset(struct virtio_device *vdev)
+{
+	struct mlxbf_tmfifo_vdev *tm_vdev;
+
+	tm_vdev = container_of(vdev, struct mlxbf_tmfifo_vdev, vdev);
+	tm_vdev->status = 0;
+}
+
+/* Read the value of a configuration field. */
+static void mlxbf_tmfifo_virtio_get(struct virtio_device *vdev,
+			      unsigned int offset,
+			      void *buf,
+			      unsigned int len)
+{
+	struct mlxbf_tmfifo_vdev *tm_vdev;
+
+	tm_vdev = container_of(vdev, struct mlxbf_tmfifo_vdev, vdev);
+
+	if (offset + len > sizeof(tm_vdev->config) || offset + len < len) {
+		dev_err(vdev->dev.parent, "virtio_get access out of bounds\n");
+		return;
+	}
+
+	memcpy(buf, (u8 *)&tm_vdev->config + offset, len);
+}
+
+/* Write the value of a configuration field. */
+static void mlxbf_tmfifo_virtio_set(struct virtio_device *vdev,
+				 unsigned int offset,
+				 const void *buf,
+				 unsigned int len)
+{
+	struct mlxbf_tmfifo_vdev *tm_vdev;
+
+	tm_vdev = container_of(vdev, struct mlxbf_tmfifo_vdev, vdev);
+
+	if (offset + len > sizeof(tm_vdev->config) || offset + len < len) {
+		dev_err(vdev->dev.parent, "virtio_get access out of bounds\n");
+		return;
+	}
+
+	memcpy((u8 *)&tm_vdev->config + offset, buf, len);
+}
+
+/* Virtio config operations. */
+static const struct virtio_config_ops mlxbf_tmfifo_virtio_config_ops = {
+	.get_features = mlxbf_tmfifo_virtio_get_features,
+	.finalize_features = mlxbf_tmfifo_virtio_finalize_features,
+	.find_vqs = mlxbf_tmfifo_virtio_find_vqs,
+	.del_vqs = mlxbf_tmfifo_virtio_del_vqs,
+	.reset = mlxbf_tmfifo_virtio_reset,
+	.set_status = mlxbf_tmfifo_virtio_set_status,
+	.get_status = mlxbf_tmfifo_virtio_get_status,
+	.get = mlxbf_tmfifo_virtio_get,
+	.set = mlxbf_tmfifo_virtio_set,
+};
+
+/* Create vdev type in a tmfifo. */
+int mlxbf_tmfifo_create_vdev(struct mlxbf_tmfifo *fifo, int vdev_id,
+			     u64 features, void *config, u32 size)
+{
+	struct mlxbf_tmfifo_vdev *tm_vdev;
+	int ret = 0;
+
+	mutex_lock(&fifo->lock);
+
+	tm_vdev = fifo->vdev[vdev_id];
+	if (tm_vdev != NULL) {
+		pr_err("vdev %d already exists\n", vdev_id);
+		ret = -EEXIST;
+		goto already_exist;
+	}
+
+	tm_vdev = kzalloc(sizeof(*tm_vdev), GFP_KERNEL);
+	if (!tm_vdev) {
+		ret = -ENOMEM;
+		goto already_exist;
+	}
+
+	tm_vdev->vdev.id.device = vdev_id;
+	tm_vdev->vdev.config = &mlxbf_tmfifo_virtio_config_ops;
+	tm_vdev->vdev.dev.parent = &fifo->pdev->dev;
+	tm_vdev->vdev.dev.release = mlxbf_tmfifo_virtio_dev_release;
+	tm_vdev->features = features;
+	if (config)
+		memcpy(&tm_vdev->config, config, size);
+	if (mlxbf_tmfifo_alloc_vrings(fifo, tm_vdev, vdev_id)) {
+		pr_err("Unable to allocate vring\n");
+		ret = -ENOMEM;
+		goto alloc_vring_fail;
+	}
+	if (vdev_id == VIRTIO_ID_CONSOLE) {
+		tm_vdev->tx_buf = kmalloc(MLXBF_TMFIFO_CONS_TX_BUF_SIZE,
+					  GFP_KERNEL);
+	}
+	fifo->vdev[vdev_id] = tm_vdev;
+
+	/* Register the virtio device. */
+	ret = register_virtio_device(&tm_vdev->vdev);
+	if (ret) {
+		dev_err(&fifo->pdev->dev, "register_virtio_device() failed\n");
+		goto register_fail;
+	}
+
+	mutex_unlock(&fifo->lock);
+	return 0;
+
+register_fail:
+	mlxbf_tmfifo_free_vrings(fifo, vdev_id);
+	fifo->vdev[vdev_id] = NULL;
+alloc_vring_fail:
+	kfree(tm_vdev);
+already_exist:
+	mutex_unlock(&fifo->lock);
+	return ret;
+}
+
+/* Delete vdev type from a tmfifo. */
+int mlxbf_tmfifo_delete_vdev(struct mlxbf_tmfifo *fifo, int vdev_id)
+{
+	struct mlxbf_tmfifo_vdev *tm_vdev;
+
+	mutex_lock(&fifo->lock);
+
+	/* Unregister vdev. */
+	tm_vdev = fifo->vdev[vdev_id];
+	if (tm_vdev) {
+		unregister_virtio_device(&tm_vdev->vdev);
+		mlxbf_tmfifo_free_vrings(fifo, vdev_id);
+		kfree(tm_vdev->tx_buf);
+		kfree(tm_vdev);
+		fifo->vdev[vdev_id] = NULL;
+	}
+
+	mutex_unlock(&fifo->lock);
+
+	return 0;
+}
+
+/* Device remove function. */
+static int mlxbf_tmfifo_remove(struct platform_device *pdev)
+{
+	struct mlxbf_tmfifo *fifo = platform_get_drvdata(pdev);
+	struct resource *rx_res, *tx_res;
+	int i;
+
+	if (fifo) {
+		mutex_lock(&mlxbf_tmfifo_lock);
+
+		fifo->is_ready = false;
+
+		/* Stop the timer. */
+		del_timer_sync(&fifo->timer);
+
+		/* Release interrupts. */
+		mlxbf_tmfifo_free_irqs(fifo);
+
+		/* Cancel the pending work. */
+		cancel_work_sync(&fifo->work);
+
+		for (i = 0; i < MLXBF_TMFIFO_VDEV_MAX; i++)
+			mlxbf_tmfifo_delete_vdev(fifo, i);
+
+		/* Release IO resources. */
+		if (fifo->rx_base)
+			iounmap(fifo->rx_base);
+		if (fifo->tx_base)
+			iounmap(fifo->tx_base);
+
+		platform_set_drvdata(pdev, NULL);
+		kfree(fifo);
+
+		mutex_unlock(&mlxbf_tmfifo_lock);
+	}
+
+	rx_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (rx_res)
+		release_mem_region(rx_res->start, resource_size(rx_res));
+	tx_res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	if (tx_res)
+		release_mem_region(tx_res->start, resource_size(tx_res));
+
+	return 0;
+}
+
+/* Read the configured network MAC address from efi variable. */
+static void mlxbf_tmfifo_get_cfg_mac(u8 *mac)
+{
+	efi_char16_t name[] = {
+		'R', 's', 'h', 'i', 'm', 'M', 'a', 'c', 'A', 'd', 'd', 'r', 0 };
+	efi_guid_t guid = EFI_GLOBAL_VARIABLE_GUID;
+	efi_status_t status;
+	unsigned long size;
+	u8 buf[6];
+
+	size = sizeof(buf);
+	status = efi.get_variable(name, &guid, NULL, &size, buf);
+	if (status == EFI_SUCCESS && size == sizeof(buf))
+		memcpy(mac, buf, sizeof(buf));
+}
+
+/* Probe the TMFIFO. */
+static int mlxbf_tmfifo_probe(struct platform_device *pdev)
+{
+	struct virtio_net_config net_config;
+	struct resource *rx_res, *tx_res;
+	struct mlxbf_tmfifo *fifo;
+	int i, ret;
+	u64 ctl;
+
+	/* Get the resource of the Rx & Tx FIFO. */
+	rx_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	tx_res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	if (!rx_res || !tx_res) {
+		ret = -EINVAL;
+		goto err;
+	}
+
+	if (request_mem_region(rx_res->start,
+			       resource_size(rx_res), "bf-tmfifo") == NULL) {
+		ret = -EBUSY;
+		goto early_err;
+	}
+
+	if (request_mem_region(tx_res->start,
+			       resource_size(tx_res), "bf-tmfifo") == NULL) {
+		release_mem_region(rx_res->start, resource_size(rx_res));
+		ret = -EBUSY;
+		goto early_err;
+	}
+
+	ret = -ENOMEM;
+	fifo = kzalloc(sizeof(struct mlxbf_tmfifo), GFP_KERNEL);
+	if (!fifo)
+		goto err;
+
+	fifo->pdev = pdev;
+	platform_set_drvdata(pdev, fifo);
+
+	spin_lock_init(&fifo->spin_lock);
+	INIT_WORK(&fifo->work, mlxbf_tmfifo_work_handler);
+
+	timer_setup(&fifo->timer, mlxbf_tmfifo_timer, 0);
+	fifo->timer.function = mlxbf_tmfifo_timer;
+
+	for (i = 0; i < MLXBF_TM_IRQ_CNT; i++) {
+		fifo->irq_info[i].index = i;
+		fifo->irq_info[i].fifo = fifo;
+		fifo->irq_info[i].irq = platform_get_irq(pdev, i);
+		ret = request_irq(fifo->irq_info[i].irq,
+				  mlxbf_tmfifo_irq_handler, 0,
+				  "tmfifo", &fifo->irq_info[i]);
+		if (ret) {
+			pr_err("Unable to request irq\n");
+			fifo->irq_info[i].irq = 0;
+			goto err;
+		}
+	}
+
+	fifo->rx_base = ioremap(rx_res->start, resource_size(rx_res));
+	if (!fifo->rx_base)
+		goto err;
+
+	fifo->tx_base = ioremap(tx_res->start, resource_size(tx_res));
+	if (!fifo->tx_base)
+		goto err;
+
+	/* Get Tx FIFO size and set the low/high watermark. */
+	ctl = readq(fifo->tx_base + MLXBF_TMFIFO_TX_CTL);
+	fifo->tx_fifo_size =
+		FIELD_GET(MLXBF_TMFIFO_TX_CTL__MAX_ENTRIES_MASK, ctl);
+	ctl = (ctl & ~MLXBF_TMFIFO_TX_CTL__LWM_MASK) |
+		FIELD_PREP(MLXBF_TMFIFO_TX_CTL__LWM_MASK,
+			   fifo->tx_fifo_size / 2);
+	ctl = (ctl & ~MLXBF_TMFIFO_TX_CTL__HWM_MASK) |
+		FIELD_PREP(MLXBF_TMFIFO_TX_CTL__HWM_MASK,
+			   fifo->tx_fifo_size - 1);
+	writeq(ctl, fifo->tx_base + MLXBF_TMFIFO_TX_CTL);
+
+	/* Get Rx FIFO size and set the low/high watermark. */
+	ctl = readq(fifo->rx_base + MLXBF_TMFIFO_RX_CTL);
+	fifo->rx_fifo_size =
+		FIELD_GET(MLXBF_TMFIFO_RX_CTL__MAX_ENTRIES_MASK, ctl);
+	ctl = (ctl & ~MLXBF_TMFIFO_RX_CTL__LWM_MASK) |
+		FIELD_PREP(MLXBF_TMFIFO_RX_CTL__LWM_MASK, 0);
+	ctl = (ctl & ~MLXBF_TMFIFO_RX_CTL__HWM_MASK) |
+		FIELD_PREP(MLXBF_TMFIFO_RX_CTL__HWM_MASK, 1);
+	writeq(ctl, fifo->rx_base + MLXBF_TMFIFO_RX_CTL);
+
+	mutex_init(&fifo->lock);
+
+	/* Create the console vdev. */
+	ret = mlxbf_tmfifo_create_vdev(fifo, VIRTIO_ID_CONSOLE, 0, NULL, 0);
+	if (ret)
+		goto err;
+
+	/* Create the network vdev. */
+	memset(&net_config, 0, sizeof(net_config));
+	net_config.mtu = MLXBF_TMFIFO_NET_MTU;
+	net_config.status = VIRTIO_NET_S_LINK_UP;
+	memcpy(net_config.mac, mlxbf_tmfifo_net_default_mac, 6);
+	mlxbf_tmfifo_get_cfg_mac(net_config.mac);
+	ret = mlxbf_tmfifo_create_vdev(fifo, VIRTIO_ID_NET,
+		MLXBF_TMFIFO_NET_FEATURES, &net_config, sizeof(net_config));
+	if (ret)
+		goto err;
+
+	mod_timer(&fifo->timer, jiffies + mlxbf_tmfifo_timer_interval);
+
+	fifo->is_ready = true;
+
+	return 0;
+
+err:
+	mlxbf_tmfifo_remove(pdev);
+early_err:
+	dev_err(&pdev->dev, "Probe Failed\n");
+	return ret;
+}
+
+static const struct of_device_id mlxbf_tmfifo_match[] = {
+	{ .compatible = "mellanox,bf-tmfifo" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, mlxbf_tmfifo_match);
+
+static const struct acpi_device_id mlxbf_tmfifo_acpi_match[] = {
+	{ "MLNXBF01", 0 },
+	{},
+};
+MODULE_DEVICE_TABLE(acpi, mlxbf_tmfifo_acpi_match);
+
+static struct platform_driver mlxbf_tmfifo_driver = {
+	.probe = mlxbf_tmfifo_probe,
+	.remove = mlxbf_tmfifo_remove,
+	.driver = {
+		.name = "bf-tmfifo",
+		.of_match_table = mlxbf_tmfifo_match,
+		.acpi_match_table = ACPI_PTR(mlxbf_tmfifo_acpi_match),
+	},
+};
+
+module_platform_driver(mlxbf_tmfifo_driver);
+
+MODULE_DESCRIPTION("Mellanox BlueField SoC TmFifo Driver");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Mellanox Technologies");
-- 
1.8.3.1

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ