HV: store the vbar base address in vbar's reg member

We added "union pci_bar_reg reg" to struct pci_bar in previous commit,
but only pci_pdev uses it and pci_vdev does not use it. Starting from
this commit, pci_vdev will use it:

In init_vdev_pt(), copy pbar's reg's flags portion to corresponding vbar's
reg.

When guest updates the vbar base address, the corresponding vbar reg's base
address will also be updated, so that in subsequent commits, we can eventually
remove the base member in struct pci_bar.

Rename local variable new_bar to base in vdev_pt_write_vbar

Tracked-On: #3241
Signed-off-by: dongshen <dongsheng.x.zhang@intel.com>
Reviewed-by: Eddie Dong <eddie.dong@intel.com>

hypervisor/dm/vpci/pci_pt.c

@@ -268,18 +268,41 @@ static void vdev_pt_remap_generic_mem_vbar(const struct pci_vdev *vdev, uint32_t
 	}
 }
 
+/**
+ * @brief Set the base address portion of the vbar base address register (32-bit)
+ * base: bar value with flags portion masked off
+ * @pre vbar != NULL
+ */
+static void set_vbar_base(struct pci_bar *vbar, uint32_t base)
+{
+	union pci_bar_reg bar_reg;
+
+	bar_reg.value = base;
+
+	if (vbar->is_64bit_high) {
+		/* Upper 32-bit of a 64-bit bar does not have the flags portion */
+		vbar->reg.value = bar_reg.value;
+	} else if (vbar->reg.bits.io.is_io == 1U) {
+		/* IO bar, BITS 31-2 = base address, 4-byte aligned */
+		vbar->reg.bits.io.base = bar_reg.bits.io.base;
+	} else {
+		/* MMIO bar, BITS 31-4 = base address, 16-byte aligned */
+		vbar->reg.bits.mem.base = bar_reg.bits.mem.base;
+	}
+}
+
 /**
  * @pre vdev != NULL
  * @pre (vdev->bar[idx].type == PCIBAR_NONE) || (vdev->bar[idx].type == PCIBAR_MEM32)
  */
 static void vdev_pt_write_vbar(struct pci_vdev *vdev, uint32_t offset, uint32_t val)
 {
 	uint32_t idx;
-	uint32_t new_bar, mask;
+	uint32_t base, mask;
 	bool bar_update_normal;
 	bool is_msix_table_bar;
 
-	new_bar = 0U;
+	base = 0U;
 	idx = (offset - pci_bar_offset(0U)) >> 2U;
 	mask = ~(vdev->bar[idx].size - 1U);
 
@@ -291,15 +314,17 @@ static void vdev_pt_write_vbar(struct pci_vdev *vdev, uint32_t offset, uint32_t
 	case PCIBAR_MEM32:
 		bar_update_normal = (val != (uint32_t)~0U);
 		is_msix_table_bar = (has_msix_cap(vdev) && (idx == vdev->msix.table_bar));
-		new_bar = val & mask;
+		base = val & mask;
+		set_vbar_base(&vdev->bar[idx], base);
+
 		if (bar_update_normal) {
 			if (is_msix_table_bar) {
-				vdev->bar[idx].base = new_bar;
+				vdev->bar[idx].base = base;
 				vdev_pt_remap_msix_table_bar(vdev);
 			} else {
-				vdev_pt_remap_generic_mem_vbar(vdev, idx, new_bar);
+				vdev_pt_remap_generic_mem_vbar(vdev, idx, base);
 
-				vdev->bar[idx].base = new_bar;
+				vdev->bar[idx].base = base;
 			}
 		}
 		break;
@@ -309,7 +334,8 @@ static void vdev_pt_write_vbar(struct pci_vdev *vdev, uint32_t offset, uint32_t
 		break;
 	}
 
-	pci_vdev_write_cfg_u32(vdev, offset, new_bar);
+	/* Write the vbar value to corresponding virtualized vbar reg */
+	pci_vdev_write_cfg_u32(vdev, offset, vdev->bar[idx].reg.value);
 }
 
 /**
@@ -383,9 +409,16 @@ void init_vdev_pt(struct pci_vdev *vdev)
 
 			vbar->base = 0UL;
 			if (is_bar_supported(pbar)) {
+				vbar->reg.value = pbar->reg.value;
+				vbar->reg.bits.mem.base = 0x0U; /* clear vbar base */
+				if (vbar->reg.bits.mem.type == 0x2U) {
+					/* Clear vbar 64-bit flag and set it to 32-bit */
+					vbar->reg.bits.mem.type = 0x0U;
+				}
+
 				/**
 				 * If vbar->base is 0 (unassigned), Linux kernel will reprogram the vbar on
-				 * its bar size boundary, so in order to ensure the vbar allocated by guest
+				 * its bar size boundary, so in order to ensure the MMIO vbar allocated by guest
 				 * is 4k aligned, set its size to be 4K aligned.
 				 */
 				vbar->size = round_page_up(pbar->size);
@@ -401,6 +434,7 @@ void init_vdev_pt(struct pci_vdev *vdev)
 					vdev_pt_write_vbar(vdev, pci_bar_offset(idx), (uint32_t)(vdev->ptdev_config->vbar[idx]));
 				}
 			} else {
+				vbar->reg.value = 0x0U;
 				vbar->size = 0UL;
 				vbar->type = PCIBAR_NONE;
 			}