soc/intel/common/gpio: vm index changes as PTL vm entries are not continuous

Add specific virtual wire mapping structure for:
- First pad group does not starts with bit position 0.
- vw_index and position are not continuous in between groups within a
  community.

BUG=
TEST=boot to OS and use iotools to read the registers that use 16-bit
port ID such as IOM AUX Bias Ctrl register to verify the 16-bit group
ID field.

Signed-off-by: Cliff Huang <cliff.huang@intel.com>
Change-Id: I986d4f4fe59b110e5075cab8742dfe8b336d034b
Reviewed-on: https://review.coreboot.org/c/coreboot/+/83997
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Subrata Banik <subratabanik@google.com>

src/soc/intel/common/block/gpio/gpio.c

@@ -1068,8 +1068,16 @@ bool gpio_get_vw_info(gpio_t pad, unsigned int *vw_index, unsigned int *vw_bit)
 	if (i == comm->num_vw_entries)
 		return false;
 
-	offset += pad - comm->vw_entries[i].first_pad;
-	*vw_index = comm->vw_base + offset / 8;
+	/* Adjust offset and calculate vw_index based on the mapping type */
+	if (comm->vw_map) {
+		offset = pad - comm->vw_entries[i].first_pad;
+		offset += comm->vw_map[i].start_pos;
+		*vw_index = comm->vw_map[i].base + offset / 8;
+	} else {
+		offset += pad - comm->vw_entries[i].first_pad;
+		offset += comm->vw_base;
+		*vw_index = offset / 8;
+	}
 	*vw_bit = offset % 8;
 
 	return true;

src/soc/intel/common/block/include/intelblocks/gpio.h

@@ -110,6 +110,12 @@ struct vw_entries {
 	gpio_t last_pad;
 };
 
+/* virtual-wire mapping base and the starting bit position for a group */
+struct vw_map {
+	uint8_t base;
+	uint8_t start_pos;
+};
+
 /* This structure will be used to describe a community or each group within a
  * community when multiple groups exist inside a community
  */
@@ -152,6 +158,7 @@ struct pad_community {
 	 * which they map to VW indexes (beginning with VW base)
 	 */
 	const struct vw_entries	*vw_entries;
+	const struct vw_map *vw_map;
 	size_t		num_vw_entries;
 };