}
 }
 
+static uint8_t get_lowest_dpia_index(const struct dc_link *link)
+{
+       const struct dc *dc_struct = link->dc;
+       uint8_t idx = 0xFF;
+       int i;
+
+       for (i = 0; i < MAX_PIPES * 2; ++i) {
+               if (!dc_struct->links[i] || dc_struct->links[i]->ep_type != DISPLAY_ENDPOINT_USB4_DPIA)
+                       continue;
+
+               if (idx > dc_struct->links[i]->link_index)
+                       idx = dc_struct->links[i]->link_index;
+       }
+
+       return idx;
+}
+
+static void dcn35_notify_host_router_bw(struct clk_mgr *clk_mgr_base, struct dc_state *context,
+                                       bool safe_to_lower)
+{
+       struct dc_clocks *new_clocks = &context->bw_ctx.bw.dcn.clk;
+       struct clk_mgr_internal *clk_mgr = TO_CLK_MGR_INTERNAL(clk_mgr_base);
+       uint32_t host_router_bw_kbps[MAX_HOST_ROUTERS_NUM] = { 0 };
+       int i;
+
+       for (i = 0; i < context->stream_count; ++i) {
+               const struct dc_stream_state *stream = context->streams[i];
+               const struct dc_link *link = stream->link;
+               uint8_t lowest_dpia_index = 0, hr_index = 0;
+
+               if (!link)
+                       continue;
+
+               lowest_dpia_index = get_lowest_dpia_index(link);
+               if (link->link_index < lowest_dpia_index)
+                       continue;
+
+               hr_index = (link->link_index - lowest_dpia_index) / 2;
+               host_router_bw_kbps[hr_index] += dc_bandwidth_in_kbps_from_timing(
+                       &stream->timing, dc_link_get_highest_encoding_format(link));
+       }
+
+       for (i = 0; i < MAX_HOST_ROUTERS_NUM; ++i) {
+               new_clocks->host_router_bw_kbps[i] = host_router_bw_kbps[i];
+               if (should_set_clock(safe_to_lower, new_clocks->host_router_bw_kbps[i], clk_mgr_base->clks.host_router_bw_kbps[i])) {
+                       clk_mgr_base->clks.host_router_bw_kbps[i] = new_clocks->host_router_bw_kbps[i];
+                       dcn35_smu_notify_host_router_bw(clk_mgr, i, new_clocks->host_router_bw_kbps[i]);
+               }
+       }
+}
+
 void dcn35_update_clocks(struct clk_mgr *clk_mgr_base,
                        struct dc_state *context,
                        bool safe_to_lower)
                dcn35_update_clocks_update_dpp_dto(clk_mgr, context, safe_to_lower);
        }
 
+       // notify PMFW of bandwidth per DPIA tunnel
+       if (dc->debug.notify_dpia_hr_bw)
+               dcn35_notify_host_router_bw(clk_mgr_base, context, safe_to_lower);
+
        // notify DMCUB of latest clocks
        memset(&cmd, 0, sizeof(cmd));
        cmd.notify_clocks.header.type = DMUB_CMD__CLK_MGR;
 
 #define VBIOSSMC_MSG_DisableLSdma                 0x1A ///< Disable LSDMA; only sent by VBIOS
 #define VBIOSSMC_MSG_DpControllerPhyStatus        0x1B ///< Inform PMFW about the pre conditions for turning SLDO2 on/off . bit[0]==1 precondition is met, bit[1-2] are for DPPHY number
 #define VBIOSSMC_MSG_QueryIPS2Support             0x1C ///< Return 1: support; else not supported
-#define VBIOSSMC_Message_Count                    0x1D
+#define VBIOSSMC_MSG_NotifyHostRouterBW           0x1D
+#define VBIOSSMC_Message_Count                    0x1E
 
 #define VBIOSSMC_Status_BUSY                      0x0
 #define VBIOSSMC_Result_OK                        0x1
 #define VBIOSSMC_Result_CmdRejectedPrereq         0xFD
 #define VBIOSSMC_Result_CmdRejectedBusy           0xFC
 
+union dcn35_dpia_host_router_bw {
+       struct {
+               uint32_t hr_id : 16;
+               uint32_t bw_mbps : 16;
+       } bits;
+       uint32_t all;
+};
+
 /*
  * Function to be used instead of REG_WAIT macro because the wait ends when
  * the register is NOT EQUAL to zero, and because `the translation in msg_if.h
        //smu_print("%s: VBIOSSMC_MSG_QueryIPS2Support return = %x\n", __func__, retv);
        return retv;
 }
+
+void dcn35_smu_notify_host_router_bw(struct clk_mgr_internal *clk_mgr, uint32_t hr_id, uint32_t bw_kbps)
+{
+       union dcn35_dpia_host_router_bw msg_data = { 0 };
+
+       msg_data.bits.hr_id = hr_id;
+       msg_data.bits.bw_mbps = bw_kbps / 1000;
+
+       dcn35_smu_send_msg_with_param(clk_mgr, VBIOSSMC_MSG_NotifyHostRouterBW, msg_data.all);
+}
 
 #define MAX_STREAMS 6
 #define MIN_VIEWPORT_SIZE 12
 #define MAX_NUM_EDP 2
+#define MAX_HOST_ROUTERS_NUM 2
 
 /* Display Core Interfaces */
 struct dc_versions {
        bool prev_p_state_change_support;
        bool fclk_prev_p_state_change_support;
        int num_ways;
+       int host_router_bw_kbps[MAX_HOST_ROUTERS_NUM];
 
        /*
         * @fw_based_mclk_switching
        unsigned int force_easf;
        unsigned int force_sharpness;
        unsigned int force_lls;
+       bool notify_dpia_hr_bw;
 };