ret_val = wm_ns * refclk_mhz;
        ret_val /= 1000;
 
-       if (ret_val > clamp_value)
+       if (ret_val > clamp_value) {
+               /* clamping WMs is abnormal, unexpected and may lead to underflow*/
+               ASSERT(0);
                ret_val = clamp_value;
+       }
 
        return ret_val;
 }
        if (safe_to_lower || watermarks->a.urgent_ns > hubbub2->watermarks.a.urgent_ns) {
                hubbub2->watermarks.a.urgent_ns = watermarks->a.urgent_ns;
                prog_wm_value = convert_and_clamp(watermarks->a.urgent_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0x3fff);
                REG_SET(DCHUBBUB_ARB_DATA_URGENCY_WATERMARK_A, 0,
                                DCHUBBUB_ARB_DATA_URGENCY_WATERMARK_A, prog_wm_value);
 
        if (safe_to_lower || watermarks->a.urgent_latency_ns > hubbub2->watermarks.a.urgent_latency_ns) {
                hubbub2->watermarks.a.urgent_latency_ns = watermarks->a.urgent_latency_ns;
                prog_wm_value = convert_and_clamp(watermarks->a.urgent_latency_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0x3fff);
                REG_SET(DCHUBBUB_ARB_REFCYC_PER_TRIP_TO_MEMORY_A, 0,
                                DCHUBBUB_ARB_REFCYC_PER_TRIP_TO_MEMORY_A, prog_wm_value);
        } else if (watermarks->a.urgent_latency_ns < hubbub2->watermarks.a.urgent_latency_ns)
        if (safe_to_lower || watermarks->b.urgent_ns > hubbub2->watermarks.b.urgent_ns) {
                hubbub2->watermarks.b.urgent_ns = watermarks->b.urgent_ns;
                prog_wm_value = convert_and_clamp(watermarks->b.urgent_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0x3fff);
                REG_SET(DCHUBBUB_ARB_DATA_URGENCY_WATERMARK_B, 0,
                                DCHUBBUB_ARB_DATA_URGENCY_WATERMARK_B, prog_wm_value);
 
        if (safe_to_lower || watermarks->b.urgent_latency_ns > hubbub2->watermarks.b.urgent_latency_ns) {
                hubbub2->watermarks.b.urgent_latency_ns = watermarks->b.urgent_latency_ns;
                prog_wm_value = convert_and_clamp(watermarks->b.urgent_latency_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0x3fff);
                REG_SET(DCHUBBUB_ARB_REFCYC_PER_TRIP_TO_MEMORY_B, 0,
                                DCHUBBUB_ARB_REFCYC_PER_TRIP_TO_MEMORY_B, prog_wm_value);
        } else if (watermarks->b.urgent_latency_ns < hubbub2->watermarks.b.urgent_latency_ns)
        if (safe_to_lower || watermarks->c.urgent_ns > hubbub2->watermarks.c.urgent_ns) {
                hubbub2->watermarks.c.urgent_ns = watermarks->c.urgent_ns;
                prog_wm_value = convert_and_clamp(watermarks->c.urgent_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0x3fff);
                REG_SET(DCHUBBUB_ARB_DATA_URGENCY_WATERMARK_C, 0,
                                DCHUBBUB_ARB_DATA_URGENCY_WATERMARK_C, prog_wm_value);
 
        if (safe_to_lower || watermarks->c.urgent_latency_ns > hubbub2->watermarks.c.urgent_latency_ns) {
                hubbub2->watermarks.c.urgent_latency_ns = watermarks->c.urgent_latency_ns;
                prog_wm_value = convert_and_clamp(watermarks->c.urgent_latency_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0x3fff);
                REG_SET(DCHUBBUB_ARB_REFCYC_PER_TRIP_TO_MEMORY_C, 0,
                                DCHUBBUB_ARB_REFCYC_PER_TRIP_TO_MEMORY_C, prog_wm_value);
        } else if (watermarks->c.urgent_latency_ns < hubbub2->watermarks.c.urgent_latency_ns)
        if (safe_to_lower || watermarks->d.urgent_ns > hubbub2->watermarks.d.urgent_ns) {
                hubbub2->watermarks.d.urgent_ns = watermarks->d.urgent_ns;
                prog_wm_value = convert_and_clamp(watermarks->d.urgent_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0x3fff);
                REG_SET(DCHUBBUB_ARB_DATA_URGENCY_WATERMARK_D, 0,
                                DCHUBBUB_ARB_DATA_URGENCY_WATERMARK_D, prog_wm_value);
 
        if (safe_to_lower || watermarks->d.urgent_latency_ns > hubbub2->watermarks.d.urgent_latency_ns) {
                hubbub2->watermarks.d.urgent_latency_ns = watermarks->d.urgent_latency_ns;
                prog_wm_value = convert_and_clamp(watermarks->d.urgent_latency_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0x3fff);
                REG_SET(DCHUBBUB_ARB_REFCYC_PER_TRIP_TO_MEMORY_D, 0,
                                DCHUBBUB_ARB_REFCYC_PER_TRIP_TO_MEMORY_D, prog_wm_value);
        } else if (watermarks->d.urgent_latency_ns < hubbub2->watermarks.d.urgent_latency_ns)
                                watermarks->a.cstate_pstate.cstate_enter_plus_exit_ns;
                prog_wm_value = convert_and_clamp(
                                watermarks->a.cstate_pstate.cstate_enter_plus_exit_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0xffff);
                REG_SET(DCHUBBUB_ARB_ALLOW_SR_ENTER_WATERMARK_A, 0,
                                DCHUBBUB_ARB_ALLOW_SR_ENTER_WATERMARK_A, prog_wm_value);
                DC_LOG_BANDWIDTH_CALCS("SR_ENTER_EXIT_WATERMARK_A calculated =%d\n"
                                watermarks->a.cstate_pstate.cstate_exit_ns;
                prog_wm_value = convert_and_clamp(
                                watermarks->a.cstate_pstate.cstate_exit_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0xffff);
                REG_SET(DCHUBBUB_ARB_ALLOW_SR_EXIT_WATERMARK_A, 0,
                                DCHUBBUB_ARB_ALLOW_SR_EXIT_WATERMARK_A, prog_wm_value);
                DC_LOG_BANDWIDTH_CALCS("SR_EXIT_WATERMARK_A calculated =%d\n"
                                watermarks->a.cstate_pstate.cstate_enter_plus_exit_z8_ns;
                prog_wm_value = convert_and_clamp(
                                watermarks->a.cstate_pstate.cstate_enter_plus_exit_z8_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0xffff);
                REG_SET(DCHUBBUB_ARB_ALLOW_SR_ENTER_WATERMARK_Z8_A, 0,
                                DCHUBBUB_ARB_ALLOW_SR_ENTER_WATERMARK_Z8_A, prog_wm_value);
                DC_LOG_BANDWIDTH_CALCS("SR_ENTER_WATERMARK_Z8_A calculated =%d\n"
                                watermarks->a.cstate_pstate.cstate_exit_z8_ns;
                prog_wm_value = convert_and_clamp(
                                watermarks->a.cstate_pstate.cstate_exit_z8_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0xffff);
                REG_SET(DCHUBBUB_ARB_ALLOW_SR_EXIT_WATERMARK_Z8_A, 0,
                                DCHUBBUB_ARB_ALLOW_SR_EXIT_WATERMARK_Z8_A, prog_wm_value);
                DC_LOG_BANDWIDTH_CALCS("SR_EXIT_WATERMARK_Z8_A calculated =%d\n"
                                watermarks->b.cstate_pstate.cstate_enter_plus_exit_ns;
                prog_wm_value = convert_and_clamp(
                                watermarks->b.cstate_pstate.cstate_enter_plus_exit_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0xffff);
                REG_SET(DCHUBBUB_ARB_ALLOW_SR_ENTER_WATERMARK_B, 0,
                                DCHUBBUB_ARB_ALLOW_SR_ENTER_WATERMARK_B, prog_wm_value);
                DC_LOG_BANDWIDTH_CALCS("SR_ENTER_EXIT_WATERMARK_B calculated =%d\n"
                                watermarks->b.cstate_pstate.cstate_exit_ns;
                prog_wm_value = convert_and_clamp(
                                watermarks->b.cstate_pstate.cstate_exit_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0xffff);
                REG_SET(DCHUBBUB_ARB_ALLOW_SR_EXIT_WATERMARK_B, 0,
                                DCHUBBUB_ARB_ALLOW_SR_EXIT_WATERMARK_B, prog_wm_value);
                DC_LOG_BANDWIDTH_CALCS("SR_EXIT_WATERMARK_B calculated =%d\n"
                                watermarks->b.cstate_pstate.cstate_enter_plus_exit_z8_ns;
                prog_wm_value = convert_and_clamp(
                                watermarks->b.cstate_pstate.cstate_enter_plus_exit_z8_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0xffff);
                REG_SET(DCHUBBUB_ARB_ALLOW_SR_ENTER_WATERMARK_Z8_B, 0,
                                DCHUBBUB_ARB_ALLOW_SR_ENTER_WATERMARK_Z8_B, prog_wm_value);
                DC_LOG_BANDWIDTH_CALCS("SR_ENTER_WATERMARK_Z8_B calculated =%d\n"
                                watermarks->b.cstate_pstate.cstate_exit_z8_ns;
                prog_wm_value = convert_and_clamp(
                                watermarks->b.cstate_pstate.cstate_exit_z8_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0xffff);
                REG_SET(DCHUBBUB_ARB_ALLOW_SR_EXIT_WATERMARK_Z8_B, 0,
                                DCHUBBUB_ARB_ALLOW_SR_EXIT_WATERMARK_Z8_B, prog_wm_value);
                DC_LOG_BANDWIDTH_CALCS("SR_EXIT_WATERMARK_Z8_B calculated =%d\n"
                                watermarks->c.cstate_pstate.cstate_enter_plus_exit_ns;
                prog_wm_value = convert_and_clamp(
                                watermarks->c.cstate_pstate.cstate_enter_plus_exit_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0xffff);
                REG_SET(DCHUBBUB_ARB_ALLOW_SR_ENTER_WATERMARK_C, 0,
                                DCHUBBUB_ARB_ALLOW_SR_ENTER_WATERMARK_C, prog_wm_value);
                DC_LOG_BANDWIDTH_CALCS("SR_ENTER_EXIT_WATERMARK_C calculated =%d\n"
                                watermarks->c.cstate_pstate.cstate_exit_ns;
                prog_wm_value = convert_and_clamp(
                                watermarks->c.cstate_pstate.cstate_exit_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0xffff);
                REG_SET(DCHUBBUB_ARB_ALLOW_SR_EXIT_WATERMARK_C, 0,
                                DCHUBBUB_ARB_ALLOW_SR_EXIT_WATERMARK_C, prog_wm_value);
                DC_LOG_BANDWIDTH_CALCS("SR_EXIT_WATERMARK_C calculated =%d\n"
                                watermarks->c.cstate_pstate.cstate_enter_plus_exit_z8_ns;
                prog_wm_value = convert_and_clamp(
                                watermarks->c.cstate_pstate.cstate_enter_plus_exit_z8_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0xffff);
                REG_SET(DCHUBBUB_ARB_ALLOW_SR_ENTER_WATERMARK_Z8_C, 0,
                                DCHUBBUB_ARB_ALLOW_SR_ENTER_WATERMARK_Z8_C, prog_wm_value);
                DC_LOG_BANDWIDTH_CALCS("SR_ENTER_WATERMARK_Z8_C calculated =%d\n"
                                watermarks->c.cstate_pstate.cstate_exit_z8_ns;
                prog_wm_value = convert_and_clamp(
                                watermarks->c.cstate_pstate.cstate_exit_z8_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0xffff);
                REG_SET(DCHUBBUB_ARB_ALLOW_SR_EXIT_WATERMARK_Z8_C, 0,
                                DCHUBBUB_ARB_ALLOW_SR_EXIT_WATERMARK_Z8_C, prog_wm_value);
                DC_LOG_BANDWIDTH_CALCS("SR_EXIT_WATERMARK_Z8_C calculated =%d\n"
                                watermarks->d.cstate_pstate.cstate_enter_plus_exit_ns;
                prog_wm_value = convert_and_clamp(
                                watermarks->d.cstate_pstate.cstate_enter_plus_exit_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0xffff);
                REG_SET(DCHUBBUB_ARB_ALLOW_SR_ENTER_WATERMARK_D, 0,
                                DCHUBBUB_ARB_ALLOW_SR_ENTER_WATERMARK_D, prog_wm_value);
                DC_LOG_BANDWIDTH_CALCS("SR_ENTER_EXIT_WATERMARK_D calculated =%d\n"
                                watermarks->d.cstate_pstate.cstate_exit_ns;
                prog_wm_value = convert_and_clamp(
                                watermarks->d.cstate_pstate.cstate_exit_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0xffff);
                REG_SET(DCHUBBUB_ARB_ALLOW_SR_EXIT_WATERMARK_D, 0,
                                DCHUBBUB_ARB_ALLOW_SR_EXIT_WATERMARK_D, prog_wm_value);
                DC_LOG_BANDWIDTH_CALCS("SR_EXIT_WATERMARK_D calculated =%d\n"
                                watermarks->d.cstate_pstate.cstate_enter_plus_exit_z8_ns;
                prog_wm_value = convert_and_clamp(
                                watermarks->d.cstate_pstate.cstate_enter_plus_exit_z8_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0xffff);
                REG_SET(DCHUBBUB_ARB_ALLOW_SR_ENTER_WATERMARK_Z8_D, 0,
                                DCHUBBUB_ARB_ALLOW_SR_ENTER_WATERMARK_Z8_D, prog_wm_value);
                DC_LOG_BANDWIDTH_CALCS("SR_ENTER_WATERMARK_Z8_D calculated =%d\n"
                                watermarks->d.cstate_pstate.cstate_exit_z8_ns;
                prog_wm_value = convert_and_clamp(
                                watermarks->d.cstate_pstate.cstate_exit_z8_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0xffff);
                REG_SET(DCHUBBUB_ARB_ALLOW_SR_EXIT_WATERMARK_Z8_D, 0,
                                DCHUBBUB_ARB_ALLOW_SR_EXIT_WATERMARK_Z8_D, prog_wm_value);
                DC_LOG_BANDWIDTH_CALCS("SR_EXIT_WATERMARK_Z8_D calculated =%d\n"
                                watermarks->a.cstate_pstate.pstate_change_ns;
                prog_wm_value = convert_and_clamp(
                                watermarks->a.cstate_pstate.pstate_change_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0xffff);
                REG_SET(DCHUBBUB_ARB_ALLOW_DRAM_CLK_CHANGE_WATERMARK_A, 0,
                                DCHUBBUB_ARB_ALLOW_DRAM_CLK_CHANGE_WATERMARK_A, prog_wm_value);
                DC_LOG_BANDWIDTH_CALCS("DRAM_CLK_CHANGE_WATERMARK_A calculated =%d\n"
                                watermarks->b.cstate_pstate.pstate_change_ns;
                prog_wm_value = convert_and_clamp(
                                watermarks->b.cstate_pstate.pstate_change_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0xffff);
                REG_SET(DCHUBBUB_ARB_ALLOW_DRAM_CLK_CHANGE_WATERMARK_B, 0,
                                DCHUBBUB_ARB_ALLOW_DRAM_CLK_CHANGE_WATERMARK_B, prog_wm_value);
                DC_LOG_BANDWIDTH_CALCS("DRAM_CLK_CHANGE_WATERMARK_B calculated =%d\n"
                                watermarks->c.cstate_pstate.pstate_change_ns;
                prog_wm_value = convert_and_clamp(
                                watermarks->c.cstate_pstate.pstate_change_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0xffff);
                REG_SET(DCHUBBUB_ARB_ALLOW_DRAM_CLK_CHANGE_WATERMARK_C, 0,
                                DCHUBBUB_ARB_ALLOW_DRAM_CLK_CHANGE_WATERMARK_C, prog_wm_value);
                DC_LOG_BANDWIDTH_CALCS("DRAM_CLK_CHANGE_WATERMARK_C calculated =%d\n"
                                watermarks->d.cstate_pstate.pstate_change_ns;
                prog_wm_value = convert_and_clamp(
                                watermarks->d.cstate_pstate.pstate_change_ns,
-                               refclk_mhz, 0x1fffff);
+                               refclk_mhz, 0xffff);
                REG_SET(DCHUBBUB_ARB_ALLOW_DRAM_CLK_CHANGE_WATERMARK_D, 0,
                                DCHUBBUB_ARB_ALLOW_DRAM_CLK_CHANGE_WATERMARK_D, prog_wm_value);
                DC_LOG_BANDWIDTH_CALCS("DRAM_CLK_CHANGE_WATERMARK_D calculated =%d\n"