[PATCH net-next v3 07/14] sfc: implement vdpa device config operations

From: Gautam Dawar
Date: Thu Apr 06 2023 - 03:03:01 EST


vDPA config operations can be broadly categorized in to either
virtqueue operations, device operations or DMA operations.
This patch implements most of the device level config operations.

Signed-off-by: Gautam Dawar <gautam.dawar@xxxxxxx>
---
drivers/net/ethernet/sfc/ef100_vdpa.h | 14 +++
drivers/net/ethernet/sfc/ef100_vdpa_ops.c | 131 ++++++++++++++++++++++
2 files changed, 145 insertions(+)

diff --git a/drivers/net/ethernet/sfc/ef100_vdpa.h b/drivers/net/ethernet/sfc/ef100_vdpa.h
index 1101b30f56e7..dcf4a8156415 100644
--- a/drivers/net/ethernet/sfc/ef100_vdpa.h
+++ b/drivers/net/ethernet/sfc/ef100_vdpa.h
@@ -20,6 +20,18 @@
/* Max queue pairs currently supported */
#define EF100_VDPA_MAX_QUEUES_PAIRS 1

+/* Device ID of a virtio net device */
+#define EF100_VDPA_VIRTIO_NET_DEVICE_ID VIRTIO_ID_NET
+
+/* Vendor ID of Xilinx vDPA NIC */
+#define EF100_VDPA_VENDOR_ID PCI_VENDOR_ID_XILINX
+
+/* Max number of Buffers supported in the virtqueue */
+#define EF100_VDPA_VQ_NUM_MAX_SIZE 512
+
+/* Alignment requirement of the Virtqueue */
+#define EF100_VDPA_VQ_ALIGN 4096
+
/**
* enum ef100_vdpa_nic_state - possible states for a vDPA NIC
*
@@ -60,6 +72,7 @@ enum ef100_vdpa_vq_type {
* @net_config: virtio_net_config data
* @mac_address: mac address of interface associated with this vdpa device
* @mac_configured: true after MAC address is configured
+ * @cfg_cb: callback for config change
*/
struct ef100_vdpa_nic {
struct vdpa_device vdpa_dev;
@@ -75,6 +88,7 @@ struct ef100_vdpa_nic {
struct virtio_net_config net_config;
u8 *mac_address;
bool mac_configured;
+ struct vdpa_callback cfg_cb;
};

int ef100_vdpa_init(struct efx_probe_data *probe_data);
diff --git a/drivers/net/ethernet/sfc/ef100_vdpa_ops.c b/drivers/net/ethernet/sfc/ef100_vdpa_ops.c
index f1ce011adc43..a2364ef9f492 100644
--- a/drivers/net/ethernet/sfc/ef100_vdpa_ops.c
+++ b/drivers/net/ethernet/sfc/ef100_vdpa_ops.c
@@ -9,12 +9,131 @@

#include <linux/vdpa.h>
#include "ef100_vdpa.h"
+#include "mcdi_vdpa.h"

static struct ef100_vdpa_nic *get_vdpa_nic(struct vdpa_device *vdev)
{
return container_of(vdev, struct ef100_vdpa_nic, vdpa_dev);
}

+static u32 ef100_vdpa_get_vq_align(struct vdpa_device *vdev)
+{
+ return EF100_VDPA_VQ_ALIGN;
+}
+
+static u64 ef100_vdpa_get_device_features(struct vdpa_device *vdev)
+{
+ struct ef100_vdpa_nic *vdpa_nic = get_vdpa_nic(vdev);
+ u64 features;
+ int rc;
+
+ rc = efx_vdpa_get_features(vdpa_nic->efx,
+ EF100_VDPA_DEVICE_TYPE_NET, &features);
+ if (rc) {
+ dev_err(&vdev->dev, "%s: MCDI get features error:%d\n",
+ __func__, rc);
+ /* Returning 0 as value of features will lead to failure
+ * of feature negotiation.
+ */
+ return 0;
+ }
+
+ features |= BIT_ULL(VIRTIO_NET_F_MAC);
+ return features;
+}
+
+static int ef100_vdpa_set_driver_features(struct vdpa_device *vdev,
+ u64 features)
+{
+ struct ef100_vdpa_nic *vdpa_nic = get_vdpa_nic(vdev);
+ u64 verify_features;
+ int rc;
+
+ mutex_lock(&vdpa_nic->lock);
+ verify_features = features & ~BIT_ULL(VIRTIO_NET_F_MAC);
+ rc = efx_vdpa_verify_features(vdpa_nic->efx,
+ EF100_VDPA_DEVICE_TYPE_NET,
+ verify_features);
+ if (rc) {
+ dev_err(&vdev->dev, "%s: MCDI verify features error:%d\n",
+ __func__, rc);
+ goto err;
+ }
+
+ vdpa_nic->features = features;
+err:
+ mutex_unlock(&vdpa_nic->lock);
+ return rc;
+}
+
+static u64 ef100_vdpa_get_driver_features(struct vdpa_device *vdev)
+{
+ struct ef100_vdpa_nic *vdpa_nic = get_vdpa_nic(vdev);
+
+ return vdpa_nic->features;
+}
+
+static void ef100_vdpa_set_config_cb(struct vdpa_device *vdev,
+ struct vdpa_callback *cb)
+{
+ struct ef100_vdpa_nic *vdpa_nic = get_vdpa_nic(vdev);
+
+ if (cb)
+ vdpa_nic->cfg_cb = *cb;
+}
+
+static u16 ef100_vdpa_get_vq_num_max(struct vdpa_device *vdev)
+{
+ return EF100_VDPA_VQ_NUM_MAX_SIZE;
+}
+
+static u32 ef100_vdpa_get_device_id(struct vdpa_device *vdev)
+{
+ return EF100_VDPA_VIRTIO_NET_DEVICE_ID;
+}
+
+static u32 ef100_vdpa_get_vendor_id(struct vdpa_device *vdev)
+{
+ return EF100_VDPA_VENDOR_ID;
+}
+
+static size_t ef100_vdpa_get_config_size(struct vdpa_device *vdev)
+{
+ return sizeof(struct virtio_net_config);
+}
+
+static void ef100_vdpa_get_config(struct vdpa_device *vdev,
+ unsigned int offset,
+ void *buf, unsigned int len)
+{
+ struct ef100_vdpa_nic *vdpa_nic = get_vdpa_nic(vdev);
+
+ /* Avoid the possibility of wrap-up after the sum exceeds U32_MAX */
+ if (WARN_ON(((u64)offset + len) > sizeof(struct virtio_net_config))) {
+ dev_err(&vdev->dev,
+ "%s: Offset + len exceeds config size\n", __func__);
+ return;
+ }
+ memcpy(buf, (u8 *)&vdpa_nic->net_config + offset, len);
+}
+
+static void ef100_vdpa_set_config(struct vdpa_device *vdev, unsigned int offset,
+ const void *buf, unsigned int len)
+{
+ struct ef100_vdpa_nic *vdpa_nic = get_vdpa_nic(vdev);
+
+ /* Avoid the possibility of wrap-up after the sum exceeds U32_MAX */
+ if (WARN_ON(((u64)offset + len) > sizeof(vdpa_nic->net_config))) {
+ dev_err(&vdev->dev,
+ "%s: Offset + len exceeds config size\n", __func__);
+ return;
+ }
+
+ memcpy((u8 *)&vdpa_nic->net_config + offset, buf, len);
+ if (is_valid_ether_addr(vdpa_nic->mac_address))
+ vdpa_nic->mac_configured = true;
+}
+
static void ef100_vdpa_free(struct vdpa_device *vdev)
{
struct ef100_vdpa_nic *vdpa_nic = get_vdpa_nic(vdev);
@@ -26,5 +145,17 @@ static void ef100_vdpa_free(struct vdpa_device *vdev)
}

const struct vdpa_config_ops ef100_vdpa_config_ops = {
+ .get_vq_align = ef100_vdpa_get_vq_align,
+ .get_device_features = ef100_vdpa_get_device_features,
+ .set_driver_features = ef100_vdpa_set_driver_features,
+ .get_driver_features = ef100_vdpa_get_driver_features,
+ .set_config_cb = ef100_vdpa_set_config_cb,
+ .get_vq_num_max = ef100_vdpa_get_vq_num_max,
+ .get_device_id = ef100_vdpa_get_device_id,
+ .get_vendor_id = ef100_vdpa_get_vendor_id,
+ .get_config_size = ef100_vdpa_get_config_size,
+ .get_config = ef100_vdpa_get_config,
+ .set_config = ef100_vdpa_set_config,
+ .get_generation = NULL,
.free = ef100_vdpa_free,
};
--
2.30.1