pds_vdpa: virtio bar setup for vdpa

Prep and use the "modern" virtio bar utilities to get our
virtio config space ready.
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20230519215632.12343-8-shannon.nelson@amd.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

drivers/vdpa/pds/aux_drv.c

@@ -4,6 +4,7 @@
 #include <linux/auxiliary_bus.h>
 #include <linux/pci.h>
 #include <linux/vdpa.h>
+#include <linux/virtio_pci_modern.h>
 
 #include <linux/pds/pds_common.h>
 #include <linux/pds/pds_core_if.h>
@@ -19,12 +20,22 @@ static const struct auxiliary_device_id pds_vdpa_id_table[] = {
 	{},
 };
 
+static int pds_vdpa_device_id_check(struct pci_dev *pdev)
+{
+	if (pdev->device != PCI_DEVICE_ID_PENSANDO_VDPA_VF ||
+	    pdev->vendor != PCI_VENDOR_ID_PENSANDO)
+		return -ENODEV;
+
+	return PCI_DEVICE_ID_PENSANDO_VDPA_VF;
+}
+
 static int pds_vdpa_probe(struct auxiliary_device *aux_dev,
 			  const struct auxiliary_device_id *id)
 
 {
 	struct pds_auxiliary_dev *padev =
 		container_of(aux_dev, struct pds_auxiliary_dev, aux_dev);
+	struct device *dev = &aux_dev->dev;
 	struct pds_vdpa_aux *vdpa_aux;
 	int err;
 
@@ -41,8 +52,21 @@ static int pds_vdpa_probe(struct auxiliary_device *aux_dev,
 	if (err)
 		goto err_free_mem;
 
+	/* Find the virtio configuration */
+	vdpa_aux->vd_mdev.pci_dev = padev->vf_pdev;
+	vdpa_aux->vd_mdev.device_id_check = pds_vdpa_device_id_check;
+	vdpa_aux->vd_mdev.dma_mask = DMA_BIT_MASK(PDS_CORE_ADDR_LEN);
+	err = vp_modern_probe(&vdpa_aux->vd_mdev);
+	if (err) {
+		dev_err(dev, "Unable to probe for virtio configuration: %pe\n",
+			ERR_PTR(err));
+		goto err_free_mgmt_info;
+	}
+
 	return 0;
 
+err_free_mgmt_info:
+	pci_free_irq_vectors(padev->vf_pdev);
 err_free_mem:
 	kfree(vdpa_aux);
 	auxiliary_set_drvdata(aux_dev, NULL);
@@ -55,6 +79,7 @@ static void pds_vdpa_remove(struct auxiliary_device *aux_dev)
 	struct pds_vdpa_aux *vdpa_aux = auxiliary_get_drvdata(aux_dev);
 	struct device *dev = &aux_dev->dev;
 
+	vp_modern_remove(&vdpa_aux->vd_mdev);
 	pci_free_irq_vectors(vdpa_aux->padev->vf_pdev);
 
 	kfree(vdpa_aux);

drivers/vdpa/pds/aux_drv.h

@@ -4,6 +4,8 @@
 #ifndef _AUX_DRV_H_
 #define _AUX_DRV_H_
 
+#include <linux/virtio_pci_modern.h>
+
 #define PDS_VDPA_DRV_DESCRIPTION    "AMD/Pensando vDPA VF Device Driver"
 #define PDS_VDPA_DRV_NAME           KBUILD_MODNAME
 
@@ -16,6 +18,7 @@ struct pds_vdpa_aux {
 
 	int vf_id;
 	struct dentry *dentry;
+	struct virtio_pci_modern_device vd_mdev;
 
 	int nintrs;
 };