virtio: vdpa: new SolidNET DPU driver.

This commit includes:
 1) The driver to manage the controlplane over vDPA bus.
 2) A HW monitor device to read health values from the DPU.

Signed-off-by: Alvaro Karsz <alvaro.karsz@solid-run.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20230110165638.123745-4-alvaro.karsz@solid-run.com>
Message-Id: <20230209075128.78915-1-alvaro.karsz@solid-run.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

6 files changed, 1518 insertions, 0 deletions

diff --git a/drivers/vdpa/Kconfig b/drivers/vdpa/Kconfig
index 43b716ec2d18..cd6ad92f3f05 100644
--- a/drivers/vdpa/Kconfig
+++ b/drivers/vdpa/Kconfig
@@ -98,4 +98,22 @@ config ALIBABA_ENI_VDPA
 	  VDPA driver for Alibaba ENI (Elastic Network Interface) which is built upon
 	  virtio 0.9.5 specification.
 
+ config SNET_VDPA
+	tristate "SolidRun's vDPA driver for SolidNET"
+	depends on PCI_MSI && PCI_IOV && (HWMON || HWMON=n)
+
+	# This driver MAY create a HWMON device.
+	# Depending on (HWMON || HWMON=n) ensures that:
+	# If HWMON=n the driver can be compiled either as a module or built-in.
+	# If HWMON=y the driver can be compiled either as a module or built-in.
+	# If HWMON=m the driver is forced to be compiled as a module.
+	# By doing so, IS_ENABLED can be used instead of IS_REACHABLE
+
+	help
+	  vDPA driver for SolidNET DPU.
+	  With this driver, the VirtIO dataplane can be
+	  offloaded to a SolidNET DPU.
+	  This driver includes a HW monitor device that
+	  reads health values from the DPU.
+
 endif # VDPA
diff --git a/drivers/vdpa/Makefile b/drivers/vdpa/Makefile
index 15665563a7f4..59396ff2a318 100644
--- a/drivers/vdpa/Makefile
+++ b/drivers/vdpa/Makefile
@@ -6,3 +6,4 @@ obj-$(CONFIG_IFCVF)    += ifcvf/
 obj-$(CONFIG_MLX5_VDPA) += mlx5/
 obj-$(CONFIG_VP_VDPA)    += virtio_pci/
 obj-$(CONFIG_ALIBABA_ENI_VDPA) += alibaba/
+obj-$(CONFIG_SNET_VDPA) += solidrun/
diff --git a/drivers/vdpa/solidrun/Makefile b/drivers/vdpa/solidrun/Makefile
new file mode 100644
index 000000000000..c0aa3415bf7b
--- /dev/null
+++ b/drivers/vdpa/solidrun/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_SNET_VDPA) += snet_vdpa.o
+snet_vdpa-$(CONFIG_SNET_VDPA) += snet_main.o
+ifdef CONFIG_HWMON
+snet_vdpa-$(CONFIG_SNET_VDPA) += snet_hwmon.o
+endif
diff --git a/drivers/vdpa/solidrun/snet_hwmon.c b/drivers/vdpa/solidrun/snet_hwmon.c
new file mode 100644
index 000000000000..e695e36ff753
--- /dev/null
+++ b/drivers/vdpa/solidrun/snet_hwmon.c
@@ -0,0 +1,188 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * SolidRun DPU driver for control plane
+ *
+ * Copyright (C) 2022 SolidRun
+ *
+ * Author: Alvaro Karsz <alvaro.karsz@solid-run.com>
+ *
+ */
+#include <linux/hwmon.h>
+
+#include "snet_vdpa.h"
+
+/* Monitor offsets */
+#define SNET_MON_TMP0_IN_OFF      0x00
+#define SNET_MON_TMP0_MAX_OFF     0x08
+#define SNET_MON_TMP0_CRIT_OFF    0x10
+#define SNET_MON_TMP1_IN_OFF      0x18
+#define SNET_MON_TMP1_CRIT_OFF    0x20
+#define SNET_MON_CURR_IN_OFF      0x28
+#define SNET_MON_CURR_MAX_OFF     0x30
+#define SNET_MON_CURR_CRIT_OFF    0x38
+#define SNET_MON_PWR_IN_OFF       0x40
+#define SNET_MON_VOLT_IN_OFF      0x48
+#define SNET_MON_VOLT_CRIT_OFF    0x50
+#define SNET_MON_VOLT_LCRIT_OFF   0x58
+
+static void snet_hwmon_read_reg(struct psnet *psnet, u32 reg, long *out)
+{
+	*out = psnet_read64(psnet, psnet->cfg.hwmon_off + reg);
+}
+
+static umode_t snet_howmon_is_visible(const void *data,
+				      enum hwmon_sensor_types type,
+				      u32 attr, int channel)
+{
+	return 0444;
+}
+
+static int snet_howmon_read(struct device *dev, enum hwmon_sensor_types type,
+			    u32 attr, int channel, long *val)
+{
+	struct psnet *psnet = dev_get_drvdata(dev);
+	int ret = 0;
+
+	switch (type) {
+	case hwmon_in:
+		switch (attr) {
+		case hwmon_in_lcrit:
+			snet_hwmon_read_reg(psnet, SNET_MON_VOLT_LCRIT_OFF, val);
+			break;
+		case hwmon_in_crit:
+			snet_hwmon_read_reg(psnet, SNET_MON_VOLT_CRIT_OFF, val);
+			break;
+		case hwmon_in_input:
+			snet_hwmon_read_reg(psnet, SNET_MON_VOLT_IN_OFF, val);
+			break;
+		default:
+			ret = -EOPNOTSUPP;
+			break;
+		}
+		break;
+
+	case hwmon_power:
+		switch (attr) {
+		case hwmon_power_input:
+			snet_hwmon_read_reg(psnet, SNET_MON_PWR_IN_OFF, val);
+			break;
+
+		default:
+			ret = -EOPNOTSUPP;
+			break;
+		}
+		break;
+
+	case hwmon_curr:
+		switch (attr) {
+		case hwmon_curr_input:
+			snet_hwmon_read_reg(psnet, SNET_MON_CURR_IN_OFF, val);
+			break;
+		case hwmon_curr_max:
+			snet_hwmon_read_reg(psnet, SNET_MON_CURR_MAX_OFF, val);
+			break;
+		case hwmon_curr_crit:
+			snet_hwmon_read_reg(psnet, SNET_MON_CURR_CRIT_OFF, val);
+			break;
+		default:
+			ret = -EOPNOTSUPP;
+			break;
+		}
+		break;
+
+	case hwmon_temp:
+		switch (attr) {
+		case hwmon_temp_input:
+			if (channel == 0)
+				snet_hwmon_read_reg(psnet, SNET_MON_TMP0_IN_OFF, val);
+			else
+				snet_hwmon_read_reg(psnet, SNET_MON_TMP1_IN_OFF, val);
+			break;
+		case hwmon_temp_max:
+			if (channel == 0)
+				snet_hwmon_read_reg(psnet, SNET_MON_TMP0_MAX_OFF, val);
+			else
+				ret = -EOPNOTSUPP;
+			break;
+		case hwmon_temp_crit:
+			if (channel == 0)
+				snet_hwmon_read_reg(psnet, SNET_MON_TMP0_CRIT_OFF, val);
+			else
+				snet_hwmon_read_reg(psnet, SNET_MON_TMP1_CRIT_OFF, val);
+			break;
+
+		default:
+			ret = -EOPNOTSUPP;
+			break;
+		}
+		break;
+
+	default:
+		ret = -EOPNOTSUPP;
+		break;
+	}
+	return ret;
+}
+
+static int snet_hwmon_read_string(struct device *dev,
+				  enum hwmon_sensor_types type, u32 attr,
+				  int channel, const char **str)
+{
+	int ret = 0;
+
+	switch (type) {
+	case hwmon_in:
+		*str = "main_vin";
+		break;
+	case hwmon_power:
+		*str = "soc_pin";
+		break;
+	case hwmon_curr:
+		*str = "soc_iin";
+		break;
+	case hwmon_temp:
+		if (channel == 0)
+			*str = "power_stage_temp";
+		else
+			*str = "ic_junction_temp";
+		break;
+	default:
+		ret = -EOPNOTSUPP;
+		break;
+	}
+	return ret;
+}
+
+static const struct hwmon_ops snet_hwmon_ops = {
+	.is_visible = snet_howmon_is_visible,
+	.read = snet_howmon_read,
+	.read_string = snet_hwmon_read_string
+};
+
+static const struct hwmon_channel_info *snet_hwmon_info[] = {
+	HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_LABEL),
+	HWMON_CHANNEL_INFO(power, HWMON_P_INPUT | HWMON_P_LABEL),
+	HWMON_CHANNEL_INFO(curr, HWMON_C_INPUT | HWMON_C_MAX | HWMON_C_CRIT | HWMON_C_LABEL),
+	HWMON_CHANNEL_INFO(in, HWMON_I_INPUT | HWMON_I_CRIT | HWMON_I_LCRIT | HWMON_I_LABEL),
+			   NULL
+};
+
+static const struct hwmon_chip_info snet_hwmono_info = {
+	.ops = &snet_hwmon_ops,
+	.info = snet_hwmon_info,
+};
+
+/* Create an HW monitor device */
+void psnet_create_hwmon(struct pci_dev *pdev)
+{
+	struct device *hwmon;
+	struct psnet *psnet = pci_get_drvdata(pdev);
+
+	snprintf(psnet->hwmon_name, SNET_NAME_SIZE, "snet_%s", pci_name(pdev));
+	hwmon = devm_hwmon_device_register_with_info(&pdev->dev, psnet->hwmon_name, psnet,
+						     &snet_hwmono_info, NULL);
+	/* The monitor is not mandatory, Just alert user in case of an error */
+	if (IS_ERR(hwmon))
+		SNET_WARN(pdev, "Failed to create SNET hwmon, error %ld\n", PTR_ERR(hwmon));
+}
diff --git a/drivers/vdpa/solidrun/snet_main.c b/drivers/vdpa/solidrun/snet_main.c
new file mode 100644
index 000000000000..68de727398ed
--- /dev/null
+++ b/drivers/vdpa/solidrun/snet_main.c
@@ -0,0 +1,1111 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * SolidRun DPU driver for control plane
+ *
+ * Copyright (C) 2022 SolidRun
+ *
+ * Author: Alvaro Karsz <alvaro.karsz@solid-run.com>
+ *
+ */
+#include <linux/iopoll.h>
+
+#include "snet_vdpa.h"
+
+/* SNET DPU device ID */
+#define SNET_DEVICE_ID          0x1000
+/* SNET signature */
+#define SNET_SIGNATURE          0xD0D06363
+/* Max. config version that we can work with */
+#define SNET_CFG_VERSION        0x1
+/* Queue align */
+#define SNET_QUEUE_ALIGNMENT    PAGE_SIZE
+/* Kick value to notify that new data is available */
+#define SNET_KICK_VAL           0x1
+#define SNET_CONFIG_OFF         0x0
+/* ACK timeout for a message */
+#define SNET_ACK_TIMEOUT	2000000
+/* How long we are willing to wait for a SNET device */
+#define SNET_DETECT_TIMEOUT	5000000
+/* How long should we wait for the DPU to read our config */
+#define SNET_READ_CFG_TIMEOUT	3000000
+/* Size of configs written to the DPU */
+#define SNET_GENERAL_CFG_LEN	36
+#define SNET_GENERAL_CFG_VQ_LEN	40
+
+enum snet_msg {
+	SNET_MSG_DESTROY = 1,
+};
+
+static struct snet *vdpa_to_snet(struct vdpa_device *vdpa)
+{
+	return container_of(vdpa, struct snet, vdpa);
+}
+
+static int snet_wait_for_msg_ack(struct snet *snet)
+{
+	struct pci_dev *pdev = snet->pdev;
+	int ret;
+	u32 val;
+
+	/* The DPU will clear the messages offset once messages
+	 * are processed.
+	 */
+	ret = readx_poll_timeout(ioread32, snet->bar + snet->psnet->cfg.msg_off,
+				 val, !val, 10, SNET_ACK_TIMEOUT);
+	if (ret)
+		SNET_WARN(pdev, "Timeout waiting for message ACK\n");
+
+	return ret;
+}
+
+/* Sends a message to the DPU.
+ * If blocking is set, the function will return once the
+ * message was processed by the DPU (or timeout).
+ */
+static int snet_send_msg(struct snet *snet, u32 msg, bool blocking)
+{
+	int ret = 0;
+
+	/* Make sure the DPU acked last message before issuing a new one */
+	ret = snet_wait_for_msg_ack(snet);
+	if (ret)
+		return ret;
+
+	/* Write the message */
+	snet_write32(snet, snet->psnet->cfg.msg_off, msg);
+
+	if (blocking)
+		ret = snet_wait_for_msg_ack(snet);
+	else /* If non-blocking, flush the write by issuing a read */
+		snet_read32(snet, snet->psnet->cfg.msg_off);
+
+	return ret;
+}
+
+static irqreturn_t snet_cfg_irq_hndlr(int irq, void *data)
+{
+	struct snet *snet = data;
+	/* Call callback if any */
+	if (snet->cb.callback)
+		return snet->cb.callback(snet->cb.private);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t snet_vq_irq_hndlr(int irq, void *data)
+{
+	struct snet_vq *vq = data;
+	/* Call callback if any */
+	if (vq->cb.callback)
+		return vq->cb.callback(vq->cb.private);
+
+	return IRQ_HANDLED;
+}
+
+static void snet_free_irqs(struct snet *snet)
+{
+	struct psnet *psnet = snet->psnet;
+	struct pci_dev *pdev;
+	u32 i;
+
+	/* Which Device allcoated the IRQs? */
+	if (PSNET_FLAG_ON(psnet, SNET_CFG_FLAG_IRQ_PF))
+		pdev = snet->pdev->physfn;
+	else
+		pdev = snet->pdev;
+
+	/* Free config's IRQ */
+	if (snet->cfg_irq != -1) {
+		devm_free_irq(&pdev->dev, snet->cfg_irq, snet);
+		snet->cfg_irq = -1;
+	}
+	/* Free VQ IRQs */
+	for (i = 0; i < snet->cfg->vq_num; i++) {
+		if (snet->vqs[i] && snet->vqs[i]->irq != -1) {
+			devm_free_irq(&pdev->dev, snet->vqs[i]->irq, snet->vqs[i]);
+			snet->vqs[i]->irq = -1;
+		}
+	}
+
+	/* IRQ vectors are freed when the pci remove callback is called */
+}
+
+static int snet_set_vq_address(struct vdpa_device *vdev, u16 idx, u64 desc_area,
+			       u64 driver_area, u64 device_area)
+{
+	struct snet *snet = vdpa_to_snet(vdev);
+	/* save received parameters in vqueue sturct */
+	snet->vqs[idx]->desc_area = desc_area;
+	snet->vqs[idx]->driver_area = driver_area;
+	snet->vqs[idx]->device_area = device_area;
+
+	return 0;
+}
+
+static void snet_set_vq_num(struct vdpa_device *vdev, u16 idx, u32 num)
+{
+	struct snet *snet = vdpa_to_snet(vdev);
+	/* save num in vqueue */
+	snet->vqs[idx]->num = num;
+}
+
+static void snet_kick_vq(struct vdpa_device *vdev, u16 idx)
+{
+	struct snet *snet = vdpa_to_snet(vdev);
+	/* not ready - ignore */
+	if (!snet->vqs[idx]->ready)
+		return;
+
+	iowrite32(SNET_KICK_VAL, snet->vqs[idx]->kick_ptr);
+}
+
+static void snet_set_vq_cb(struct vdpa_device *vdev, u16 idx, struct vdpa_callback *cb)
+{
+	struct snet *snet = vdpa_to_snet(vdev);
+
+	snet->vqs[idx]->cb.callback = cb->callback;
+	snet->vqs[idx]->cb.private = cb->private;
+}
+
+static void snet_set_vq_ready(struct vdpa_device *vdev, u16 idx, bool ready)
+{
+	struct snet *snet = vdpa_to_snet(vdev);
+
+	snet->vqs[idx]->ready = ready;
+}
+
+static bool snet_get_vq_ready(struct vdpa_device *vdev, u16 idx)
+{
+	struct snet *snet = vdpa_to_snet(vdev);
+
+	return snet->vqs[idx]->ready;
+}
+
+static int snet_set_vq_state(struct vdpa_device *vdev, u16 idx, const struct vdpa_vq_state *state)
+{
+	struct snet *snet = vdpa_to_snet(vdev);
+	/* Setting the VQ state is not supported.
+	 * If the asked state is the same as the initial one
+	 * we can ignore it.
+	 */
+	if (SNET_HAS_FEATURE(snet, VIRTIO_F_RING_PACKED)) {
+		const struct vdpa_vq_state_packed *p = &state->packed;
+
+		if (p->last_avail_counter == 1 && p->last_used_counter == 1 &&
+		    p->last_avail_idx == 0 && p->last_used_idx == 0)
+			return 0;
+	} else {
+		const struct vdpa_vq_state_split *s = &state->split;
+
+		if (s->avail_index == 0)
+			return 0;
+	}
+
+	return -EOPNOTSUPP;
+}
+
+static int snet_get_vq_state(struct vdpa_device *vdev, u16 idx, struct vdpa_vq_state *state)
+{
+	/* Not supported */
+	return -EOPNOTSUPP;
+}
+
+static int snet_get_vq_irq(struct vdpa_device *vdev, u16 idx)
+{
+	struct snet *snet = vdpa_to_snet(vdev);
+
+	return snet->vqs[idx]->irq;
+}
+
+static u32 snet_get_vq_align(struct vdpa_device *vdev)
+{
+	return (u32)SNET_QUEUE_ALIGNMENT;
+}
+
+static int snet_reset_dev(struct snet *snet)
+{
+	struct pci_dev *pdev = snet->pdev;
+	int ret = 0;
+	u32 i;
+
+	/* If status is 0, nothing to do */
+	if (!snet->status)
+		return 0;
+
+	/* If DPU started, send a destroy message */
+	if (snet->status & VIRTIO_CONFIG_S_DRIVER_OK)
+		ret = snet_send_msg(snet, SNET_MSG_DESTROY, true);
+
+	/* Clear VQs */
+	for (i = 0; i < snet->cfg->vq_num; i++) {
+		if (!snet->vqs[i])
+			continue;
+		snet->vqs[i]->cb.callback = NULL;
+		snet->vqs[i]->cb.private = NULL;
+		snet->vqs[i]->desc_area = 0;
+		snet->vqs[i]->device_area = 0;
+		snet->vqs[i]->driver_area = 0;
+		snet->vqs[i]->ready = false;
+	}
+
+	/* Clear config callback */
+	snet->cb.callback = NULL;
+	snet->cb.private = NULL;
+	/* Free IRQs */
+	snet_free_irqs(snet);
+	/* Reset status */
+	snet->status = 0;
+	snet->dpu_ready = false;
+
+	if (ret)
+		SNET_WARN(pdev, "Incomplete reset to SNET[%u] device\n", snet->sid);
+	else
+		SNET_DBG(pdev, "Reset SNET[%u] device\n", snet->sid);
+
+	return 0;
+}
+
+static int snet_reset(struct vdpa_device *vdev)
+{
+	struct snet *snet = vdpa_to_snet(vdev);
+
+	return snet_reset_dev(snet);
+}
+
+static size_t snet_get_config_size(struct vdpa_device *vdev)
+{
+	struct snet *snet = vdpa_to_snet(vdev);
+
+	return (size_t)snet->cfg->cfg_size;
+}
+
+static u64 snet_get_features(struct vdpa_device *vdev)
+{
+	struct snet *snet = vdpa_to_snet(vdev);
+
+	return snet->cfg->features;
+}
+
+static int snet_set_drv_features(struct vdpa_device *vdev, u64 features)
+{
+	struct snet *snet = vdpa_to_snet(vdev);
+
+	snet->negotiated_features = snet->cfg->features & features;
+	return 0;
+}
+
+static u64 snet_get_drv_features(struct vdpa_device *vdev)
+{
+	struct snet *snet = vdpa_to_snet(vdev);
+
+	return snet->negotiated_features;
+}
+
+static u16 snet_get_vq_num_max(struct vdpa_device *vdev)
+{
+	struct snet *snet = vdpa_to_snet(vdev);
+
+	return (u16)snet->cfg->vq_size;
+}
+
+static void snet_set_config_cb(struct vdpa_device *vdev, struct vdpa_callback *cb)
+{
+	struct snet *snet = vdpa_to_snet(vdev);
+
+	snet->cb.callback = cb->callback;
+	snet->cb.private = cb->private;
+}
+
+static u32 snet_get_device_id(struct vdpa_device *vdev)
+{
+	struct snet *snet = vdpa_to_snet(vdev);
+
+	return snet->cfg->virtio_id;
+}
+
+static u32 snet_get_vendor_id(struct vdpa_device *vdev)
+{
+	return (u32)PCI_VENDOR_ID_SOLIDRUN;
+}
+
+static u8 snet_get_status(struct vdpa_device *vdev)
+{
+	struct snet *snet = vdpa_to_snet(vdev);
+
+	return snet->status;
+}
+
+static int snet_write_conf(struct snet *snet)
+{
+	u32 off, i, tmp;
+	int ret;
+
+	/* No need to write the config twice */
+	if (snet->dpu_ready)
+		return true;
+
+	/* Snet data :
+	 *
+	 * General data: SNET_GENERAL_CFG_LEN bytes long
+	 *  0             0x4       0x8        0xC               0x10      0x14        0x1C     0x24
+	 *  | MAGIC NUMBER | CFG VER | SNET SID | NUMBER OF QUEUES | IRQ IDX | FEATURES |  RSVD  |
+	 *
+	 * For every VQ: SNET_GENERAL_CFG_VQ_LEN bytes long
+	 * 0                          0x4        0x8
+	 * |  VQ SID  AND  QUEUE SIZE | IRQ Index |
+	 * |             DESC AREA                |
+	 * |            DEVICE AREA               |
+	 * |            DRIVER AREA               |
+	 * |             RESERVED                 |
+	 *
+	 * Magic number should be written last, this is the DPU indication that the data is ready
+	 */
+
+	/* Init offset */
+	off = snet->psnet->cfg.host_cfg_off;
+
+	/* Ignore magic number for now */
+	off += 4;
+	snet_write32(snet, off, snet->psnet->negotiated_cfg_ver);
+	off += 4;
+	snet_write32(snet, off, snet->sid);
+	off += 4;
+	snet_write32(snet, off, snet->cfg->vq_num);
+	off += 4;
+	snet_write32(snet, off, snet->cfg_irq_idx);
+	off += 4;
+	snet_write64(snet, off, snet->negotiated_features);
+	off += 8;
+	/* Ignore reserved */
+	off += 8;
+	/* Write VQs */
+	for (i = 0 ; i < snet->cfg->vq_num ; i++) {
+		tmp = (i << 16) | (snet->vqs[i]->num & 0xFFFF);
+		snet_write32(snet, off, tmp);
+		off += 4;
+		snet_write32(snet, off, snet->vqs[i]->irq_idx);
+		off += 4;
+		snet_write64(snet, off, snet->vqs[i]->desc_area);
+		off += 8;
+		snet_write64(snet, off, snet->vqs[i]->device_area);
+		off += 8;
+		snet_write64(snet, off, snet->vqs[i]->driver_area);
+		off += 8;
+		/* Ignore reserved */
+		off += 8;
+	}
+
+	/* Clear snet messages address for this device */
+	snet_write32(snet, snet->psnet->cfg.msg_off, 0);
+	/* Write magic number - data is ready */
+	snet_write32(snet, snet->psnet->cfg.host_cfg_off, SNET_SIGNATURE);
+
+	/* The DPU will ACK the config by clearing the signature */
+	ret = readx_poll_timeout(ioread32, snet->bar + snet->psnet->cfg.host_cfg_off,
+				 tmp, !tmp, 10, SNET_READ_CFG_TIMEOUT);
+	if (ret) {
+		SNET_ERR(snet->pdev, "Timeout waiting for the DPU to read the config\n");
+		return false;
+	}
+
+	/* set DPU flag */
+	snet->dpu_ready = true;
+
+	return true;
+}
+
+static int snet_request_irqs(struct pci_dev *pdev, struct snet *snet)
+{
+	int ret, i, irq;
+
+	/* Request config IRQ */
+	irq = pci_irq_vector(pdev, snet->cfg_irq_idx);
+	ret = devm_request_irq(&pdev->dev, irq, snet_cfg_irq_hndlr, 0,
+			       snet->cfg_irq_name, snet);
+	if (ret) {
+		SNET_ERR(pdev, "Failed to request IRQ\n");
+		return ret;
+	}
+	snet->cfg_irq = irq;
+
+	/* Request IRQ for every VQ */
+	for (i = 0; i < snet->cfg->vq_num; i++) {
+		irq = pci_irq_vector(pdev, snet->vqs[i]->irq_idx);
+		ret = devm_request_irq(&pdev->dev, irq, snet_vq_irq_hndlr, 0,
+				       snet->vqs[i]->irq_name, snet->vqs[i]);
+		if (ret) {
+			SNET_ERR(pdev, "Failed to request IRQ\n");
+			return ret;
+		}
+		snet->vqs[i]->irq = irq;
+	}
+	return 0;
+}
+
+static void snet_set_status(struct vdpa_device *vdev, u8 status)
+{
+	struct snet *snet = vdpa_to_snet(vdev);
+	struct psnet *psnet = snet->psnet;
+	struct pci_dev *pdev = snet->pdev;
+	int ret;
+	bool pf_irqs;
+
+	if (status == snet->status)
+		return;
+
+	if ((status & VIRTIO_CONFIG_S_DRIVER_OK) &&
+	    !(snet->status & VIRTIO_CONFIG_S_DRIVER_OK)) {
+		/* Request IRQs */
+		pf_irqs = PSNET_FLAG_ON(psnet, SNET_CFG_FLAG_IRQ_PF);
+		ret = snet_request_irqs(pf_irqs ? pdev->physfn : pdev, snet);
+		if (ret)
+			goto set_err;
+
+		/* Write config to the DPU */
+		if (snet_write_conf(snet)) {
+			SNET_INFO(pdev, "Create SNET[%u] device\n", snet->sid);
+		} else {
+			snet_free_irqs(snet);
+			goto set_err;
+		}
+	}
+
+	/* Save the new status */
+	snet->status = status;
+	return;
+
+set_err:
+	snet->status |= VIRTIO_CONFIG_S_FAILED;
+}
+
+static void snet_get_config(struct vdpa_device *vdev, unsigned int offset,
+			    void *buf, unsigned int len)
+{
+	struct snet *snet = vdpa_to_snet(vdev);
+	void __iomem *cfg_ptr = snet->cfg->virtio_cfg + offset;
+	u8 *buf_ptr = buf;
+	u32 i;
+
+	/* check for offset error */
+	if (offset + len > snet->cfg->cfg_size)
+		return;
+
+	/* Write into buffer */
+	for (i = 0; i < len; i++)
+		*buf_ptr++ = ioread8(cfg_ptr + i);
+}
+
+static void snet_set_config(struct vdpa_device *vdev, unsigned int offset,
+			    const void *buf, unsigned int len)
+{
+	struct snet *snet = vdpa_to_snet(vdev);
+	void __iomem *cfg_ptr = snet->cfg->virtio_cfg + offset;
+	const u8 *buf_ptr = buf;
+	u32 i;
+
+	/* check for offset error */
+	if (offset + len > snet->cfg->cfg_size)
+		return;
+
+	/* Write into PCI BAR */
+	for (i = 0; i < len; i++)
+		iowrite8(*buf_ptr++, cfg_ptr + i);
+}
+
+static const struct vdpa_config_ops snet_config_ops = {
+	.set_vq_address         = snet_set_vq_address,
+	.set_vq_num             = snet_set_vq_num,
+	.kick_vq                = snet_kick_vq,
+	.set_vq_cb              = snet_set_vq_cb,
+	.set_vq_ready           = snet_set_vq_ready,
+	.get_vq_ready           = snet_get_vq_ready,
+	.set_vq_state           = snet_set_vq_state,
+	.get_vq_state           = snet_get_vq_state,
+	.get_vq_irq		= snet_get_vq_irq,
+	.get_vq_align           = snet_get_vq_align,
+	.reset                  = snet_reset,
+	.get_config_size        = snet_get_config_size,
+	.get_device_features    = snet_get_features,
+	.set_driver_features    = snet_set_drv_features,
+	.get_driver_features    = snet_get_drv_features,
+	.get_vq_num_min         = snet_get_vq_num_max,
+	.get_vq_num_max         = snet_get_vq_num_max,
+	.set_config_cb          = snet_set_config_cb,
+	.get_device_id          = snet_get_device_id,
+	.get_vendor_id          = snet_get_vendor_id,
+	.get_status             = snet_get_status,
+	.set_status             = snet_set_status,
+	.get_config             = snet_get_config,
+	.set_config             = snet_set_config,
+};
+
+static int psnet_open_pf_bar(struct pci_dev *pdev, struct psnet *psnet)
+{
+	char name[50];
+	int ret, i, mask = 0;
+	/* We don't know which BAR will be used to communicate..
+	 * We will map every bar with len > 0.
+	 *
+	 * Later, we will discover the BAR and unmap all other BARs.
+	 */
+	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
+		if (pci_resource_len(pdev, i))
+			mask |= (1 << i);
+	}
+
+	/* No BAR can be used.. */
+	if (!mask) {
+		SNET_ERR(pdev, "Failed to find a PCI BAR\n");
+		return -ENODEV;
+	}
+
+	snprintf(name, sizeof(name), "psnet[%s]-bars", pci_name(pdev));
+	ret = pcim_iomap_regions(pdev, mask, name);
+	if (ret) {
+		SNET_ERR(pdev, "Failed to request and map PCI BARs\n");
+		return ret;
+	}
+
+	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
+		if (mask & (1 << i))
+			psnet->bars[i] = pcim_iomap_table(pdev)[i];
+	}
+
+	return 0;
+}
+
+static int snet_open_vf_bar(struct pci_dev *pdev, struct snet *snet)
+{
+	char name[50];
+	int ret;
+
+	snprintf(name, sizeof(name), "snet[%s]-bar", pci_name(pdev));
+	/* Request and map BAR */
+	ret = pcim_iomap_regions(pdev, BIT(snet->psnet->cfg.vf_bar), name);
+	if (ret) {
+		SNET_ERR(pdev, "Failed to request and map PCI BAR for a VF\n");
+		return ret;
+	}
+
+	snet->bar = pcim_iomap_table(pdev)[snet->psnet->cfg.vf_bar];
+
+	return 0;
+}
+
+static void snet_free_cfg(struct snet_cfg *cfg)
+{
+	u32 i;
+
+	if (!cfg->devs)
+		return;
+
+	/* Free devices */
+	for (i = 0; i < cfg->devices_num; i++) {
+		if (!cfg->devs[i])
+			break;
+
+		kfree(cfg->devs[i]);
+	}
+	/* Free pointers to devices */
+	kfree(cfg->devs);
+}
+
+/* Detect which BAR is used for communication with the device. */
+static int psnet_detect_bar(struct psnet *psnet, u32 off)
+{
+	unsigned long exit_time;
+	int i;
+
+	exit_time = jiffies + usecs_to_jiffies(SNET_DETECT_TIMEOUT);
+
+	/* SNET DPU will write SNET's signature when the config is ready. */
+	while (time_before(jiffies, exit_time)) {
+		for (i = 0; i < PCI_STD_NUM_BARS; i++) {
+			/* Is this BAR mapped? */
+			if (!psnet->bars[i])
+				continue;
+
+			if (ioread32(psnet->bars[i] + off) == SNET_SIGNATURE)
+				return i;
+		}
+		usleep_range(1000, 10000);
+	}
+
+	return -ENODEV;
+}
+
+static void psnet_unmap_unused_bars(struct pci_dev *pdev, struct psnet *psnet)
+{
+	int i, mask = 0;
+
+	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
+		if (psnet->bars[i] && i != psnet->barno)
+			mask |= (1 << i);
+	}
+
+	if (mask)
+		pcim_iounmap_regions(pdev, mask);
+}
+
+/* Read SNET config from PCI BAR */
+static int psnet_read_cfg(struct pci_dev *pdev, struct psnet *psnet)
+{
+	struct snet_cfg *cfg = &psnet->cfg;
+	u32 i, off;
+	int barno;
+
+	/* Move to where the config starts */
+	off = SNET_CONFIG_OFF;
+
+	/* Find BAR used for communication */
+	barno = psnet_detect_bar(psnet, off);
+	if (barno < 0) {
+		SNET_ERR(pdev, "SNET config is not ready.\n");
+		return barno;
+	}
+
+	/* Save used BAR number and unmap all other BARs */
+	psnet->barno = barno;
+	SNET_DBG(pdev, "Using BAR number %d\n", barno);
+
+	psnet_unmap_unused_bars(pdev, psnet);
+
+	/* load config from BAR */
+	cfg->key = psnet_read32(psnet, off);
+	off += 4;
+	cfg->cfg_size = psnet_read32(psnet, off);
+	off += 4;
+	cfg->cfg_ver = psnet_read32(psnet, off);
+	off += 4;
+	/* The negotiated config version is the lower one between this driver's config
+	 * and the DPU's.
+	 */
+	psnet->negotiated_cfg_ver = min_t(u32, cfg->cfg_ver, SNET_CFG_VERSION);
+	SNET_DBG(pdev, "SNET config version %u\n", psnet->negotiated_cfg_ver);
+
+	cfg->vf_num = psnet_read32(psnet, off);
+	off += 4;
+	cfg->vf_bar = psnet_read32(psnet, off);
+	off += 4;
+	cfg->host_cfg_off = psnet_read32(psnet, off);
+	off += 4;
+	cfg->max_size_host_cfg = psnet_read32(psnet, off);
+	off += 4;
+	cfg->virtio_cfg_off = psnet_read32(psnet, off);
+	off += 4;
+	cfg->kick_off = psnet_read32(psnet, off);
+	off += 4;
+	cfg->hwmon_off = psnet_read32(psnet, off);
+	off += 4;
+	cfg->msg_off = psnet_read32(psnet, off);
+	off += 4;
+	cfg->flags = psnet_read32(psnet, off);
+	off += 4;
+	/* Ignore Reserved */
+	off += sizeof(cfg->rsvd);
+
+	cfg->devices_num = psnet_read32(psnet, off);
+	off += 4;
+	/* Allocate memory to hold pointer to the devices */
+	cfg->devs = kcalloc(cfg->devices_num, sizeof(void *), GFP_KERNEL);
+	if (!cfg->devs)
+		return -ENOMEM;
+
+	/* Load device configuration from BAR */
+	for (i = 0; i < cfg->devices_num; i++) {
+		cfg->devs[i] = kzalloc(sizeof(*cfg->devs[i]), GFP_KERNEL);
+		if (!cfg->devs[i]) {
+			snet_free_cfg(cfg);
+			return -ENOMEM;
+		}
+		/* Read device config */
+		cfg->devs[i]->virtio_id = psnet_read32(psnet, off);
+		off += 4;
+		cfg->devs[i]->vq_num = psnet_read32(psnet, off);
+		off += 4;
+		cfg->devs[i]->vq_size = psnet_read32(psnet, off);
+		off += 4;
+		cfg->devs[i]->vfid = psnet_read32(psnet, off);
+		off += 4;
+		cfg->devs[i]->features = psnet_read64(psnet, off);
+		off += 8;
+		/* Ignore Reserved */
+		off += sizeof(cfg->devs[i]->rsvd);
+
+		cfg->devs[i]->cfg_size = psnet_read32(psnet, off);
+		off += 4;
+
+		/* Is the config witten to the DPU going to be too big? */
+		if (SNET_GENERAL_CFG_LEN + SNET_GENERAL_CFG_VQ_LEN * cfg->devs[i]->vq_num >
+		    cfg->max_size_host_cfg) {
+			SNET_ERR(pdev, "Failed to read SNET config, the config is too big..\n");
+			snet_free_cfg(cfg);
+			return -EINVAL;
+		}
+	}
+	return 0;
+}
+
+static int psnet_alloc_irq_vector(struct pci_dev *pdev, struct psnet *psnet)
+{
+	int ret = 0;
+	u32 i, irq_num = 0;
+
+	/* Let's count how many IRQs we need, 1 for every VQ + 1 for config change */
+	for (i = 0; i < psnet->cfg.devices_num; i++)
+		irq_num += psnet->cfg.devs[i]->vq_num + 1;
+
+	ret = pci_alloc_irq_vectors(pdev, irq_num, irq_num, PCI_IRQ_MSIX);
+	if (ret != irq_num) {
+		SNET_ERR(pdev, "Failed to allocate IRQ vectors\n");
+		return ret;
+	}
+	SNET_DBG(pdev, "Allocated %u IRQ vectors from physical function\n", irq_num);
+
+	return 0;
+}
+
+static int snet_alloc_irq_vector(struct pci_dev *pdev, struct snet_dev_cfg *snet_cfg)
+{
+	int ret = 0;
+	u32 irq_num;
+
+	/* We want 1 IRQ for every VQ + 1 for config change events */
+	irq_num = snet_cfg->vq_num + 1;
+
+	ret = pci_alloc_irq_vectors(pdev, irq_num, irq_num, PCI_IRQ_MSIX);
+	if (ret <= 0) {
+		SNET_ERR(pdev, "Failed to allocate IRQ vectors\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static void snet_free_vqs(struct snet *snet)
+{
+	u32 i;
+
+	if (!snet->vqs)
+		return;
+
+	for (i = 0 ; i < snet->cfg->vq_num ; i++) {
+		if (!snet->vqs[i])
+			break;
+
+		kfree(snet->vqs[i]);
+	}
+	kfree(snet->vqs);
+}
+
+static int snet_build_vqs(struct snet *snet)
+{
+	u32 i;
+	/* Allocate the VQ pointers array */
+	snet->vqs = kcalloc(snet->cfg->vq_num, sizeof(void *), GFP_KERNEL);
+	if (!snet->vqs)
+		return -ENOMEM;
+
+	/* Allocate the VQs */
+	for (i = 0; i < snet->cfg->vq_num; i++) {
+		snet->vqs[i] = kzalloc(sizeof(*snet->vqs[i]), GFP_KERNEL);
+		if (!snet->vqs[i]) {
+			snet_free_vqs(snet);
+			return -ENOMEM;
+		}
+		/* Reset IRQ num */
+		snet->vqs[i]->irq = -1;
+		/* VQ serial ID */
+		snet->vqs[i]->sid = i;
+		/* Kick address - every VQ gets 4B */
+		snet->vqs[i]->kick_ptr = snet->bar + snet->psnet->cfg.kick_off +
+					 snet->vqs[i]->sid * 4;
+		/* Clear kick address for this VQ */
+		iowrite32(0, snet->vqs[i]->kick_ptr);
+	}
+	return 0;
+}
+
+static int psnet_get_next_irq_num(struct psnet *psnet)
+{
+	int irq;
+
+	spin_lock(&psnet->lock);
+	irq = psnet->next_irq++;
+	spin_unlock(&psnet->lock);
+
+	return irq;
+}
+
+static void snet_reserve_irq_idx(struct pci_dev *pdev, struct snet *snet)
+{
+	struct psnet *psnet = snet->psnet;
+	int  i;
+
+	/* one IRQ for every VQ, and one for config changes */
+	snet->cfg_irq_idx = psnet_get_next_irq_num(psnet);
+	snprintf(snet->cfg_irq_name, SNET_NAME_SIZE, "snet[%s]-cfg[%d]",
+		 pci_name