thunderbolt: Add functions to support DisplayPort bandwidth allocation mode

USB4 spec defines an additional feature that DP IN adapters can
implement (alongside with the graphics DPCD register set) to support
more dynamic bandwidth management for DisplayPort tunnels. For the
connection manager the communication happens through the DP IN adapter
using a set of registers in the adapter config space allocated for this.
Add functions that export this functionality for the rest of the driver.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

drivers/thunderbolt/tb.h

@@ -1238,6 +1238,21 @@ int usb4_usb3_port_allocate_bandwidth(struct tb_port *port, int *upstream_bw,
 int usb4_usb3_port_release_bandwidth(struct tb_port *port, int *upstream_bw,
 				     int *downstream_bw);
 
+int usb4_dp_port_set_cm_id(struct tb_port *port, int cm_id);
+bool usb4_dp_port_bw_mode_supported(struct tb_port *port);
+bool usb4_dp_port_bw_mode_enabled(struct tb_port *port);
+int usb4_dp_port_set_cm_bw_mode_supported(struct tb_port *port, bool supported);
+int usb4_dp_port_group_id(struct tb_port *port);
+int usb4_dp_port_set_group_id(struct tb_port *port, int group_id);
+int usb4_dp_port_nrd(struct tb_port *port, int *rate, int *lanes);
+int usb4_dp_port_set_nrd(struct tb_port *port, int rate, int lanes);
+int usb4_dp_port_granularity(struct tb_port *port);
+int usb4_dp_port_set_granularity(struct tb_port *port, int granularity);
+int usb4_dp_port_set_estimated_bw(struct tb_port *port, int bw);
+int usb4_dp_port_allocated_bw(struct tb_port *port);
+int usb4_dp_port_allocate_bw(struct tb_port *port, int bw);
+int usb4_dp_port_requested_bw(struct tb_port *port);
+
 static inline bool tb_is_usb4_port_device(const struct device *dev)
 {
 	return dev->type == &usb4_port_device_type;

drivers/thunderbolt/tb_regs.h

@@ -385,15 +385,42 @@ struct tb_regs_port_header {
 #define ADP_DP_CS_1_AUX_RX_HOPID_MASK		GENMASK(21, 11)
 #define ADP_DP_CS_1_AUX_RX_HOPID_SHIFT		11
 #define ADP_DP_CS_2				0x02
+#define ADP_DP_CS_2_NRD_MLC_MASK		GENMASK(2, 0)
 #define ADP_DP_CS_2_HDP				BIT(6)
+#define ADP_DP_CS_2_NRD_MLR_MASK		GENMASK(9, 7)
+#define ADP_DP_CS_2_NRD_MLR_SHIFT		7
+#define ADP_DP_CS_2_CA				BIT(10)
+#define ADP_DP_CS_2_GR_MASK			GENMASK(12, 11)
+#define ADP_DP_CS_2_GR_SHIFT			11
+#define ADP_DP_CS_2_GR_0_25G			0x0
+#define ADP_DP_CS_2_GR_0_5G			0x1
+#define ADP_DP_CS_2_GR_1G			0x2
+#define ADP_DP_CS_2_GROUP_ID_MASK		GENMASK(15, 13)
+#define ADP_DP_CS_2_GROUP_ID_SHIFT		13
+#define ADP_DP_CS_2_CM_ID_MASK			GENMASK(19, 16)
+#define ADP_DP_CS_2_CM_ID_SHIFT			16
+#define ADP_DP_CS_2_CMMS			BIT(20)
+#define ADP_DP_CS_2_ESTIMATED_BW_MASK		GENMASK(31, 24)
+#define ADP_DP_CS_2_ESTIMATED_BW_SHIFT		24
 #define ADP_DP_CS_3				0x03
 #define ADP_DP_CS_3_HDPC			BIT(9)
 #define DP_LOCAL_CAP				0x04
 #define DP_REMOTE_CAP				0x05
+/* For DP IN adapter */
+#define DP_STATUS				0x06
+#define DP_STATUS_ALLOCATED_BW_MASK		GENMASK(31, 24)
+#define DP_STATUS_ALLOCATED_BW_SHIFT		24
+/* For DP OUT adapter */
 #define DP_STATUS_CTRL				0x06
 #define DP_STATUS_CTRL_CMHS			BIT(25)
 #define DP_STATUS_CTRL_UF			BIT(26)
 #define DP_COMMON_CAP				0x07
+/* Only if DP IN supports BW allocation mode */
+#define ADP_DP_CS_8				0x08
+#define ADP_DP_CS_8_REQUESTED_BW_MASK		GENMASK(7, 0)
+#define ADP_DP_CS_8_DPME			BIT(30)
+#define ADP_DP_CS_8_DR				BIT(31)
+
 /*
  * DP_COMMON_CAP offsets work also for DP_LOCAL_CAP and DP_REMOTE_CAP
  * with exception of DPRX done.
@@ -410,7 +437,12 @@ struct tb_regs_port_header {
 #define DP_COMMON_CAP_2_LANES			0x1
 #define DP_COMMON_CAP_4_LANES			0x2
 #define DP_COMMON_CAP_LTTPR_NS			BIT(27)
+#define DP_COMMON_CAP_BW_MODE			BIT(28)
 #define DP_COMMON_CAP_DPRX_DONE			BIT(31)
+/* Only present if DP IN supports BW allocation mode */
+#define ADP_DP_CS_8				0x08
+#define ADP_DP_CS_8_DPME			BIT(30)
+#define ADP_DP_CS_8_DR				BIT(31)
 
 /* PCIe adapter registers */
 #define ADP_PCIE_CS_0				0x00