diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c
index 8796a8929d89..134c57ca10b7 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c
@@ -94,6 +94,9 @@ static int slpc_shared_data_init(struct intel_guc_slpc *slpc)
 		return err;
 	}
 
+	slpc->max_freq_softlimit = 0;
+	slpc->min_freq_softlimit = 0;
+
 	return err;
 }
 
@@ -121,6 +124,19 @@ static int guc_action_slpc_set_param(struct intel_guc *guc, u8 id, u32 value)
  	return intel_guc_send(guc, request, ARRAY_SIZE(request));
 }
 
+static int guc_action_slpc_unset_param(struct intel_guc *guc,
+					u8 id)
+{
+	u32 request[] = {
+		INTEL_GUC_ACTION_SLPC_REQUEST,
+ 		SLPC_EVENT(SLPC_EVENT_PARAMETER_UNSET, 2),
+		id,
+	};
+
+ 	return intel_guc_send(guc, request, ARRAY_SIZE(request));
+}
+
+
 static bool slpc_is_running(struct intel_guc_slpc *slpc)
 {
 	return (slpc_get_state(slpc) == SLPC_GLOBAL_STATE_RUNNING);
@@ -164,6 +180,16 @@ static int slpc_set_param(struct intel_guc_slpc *slpc, u8 id, u32 value)
 	return guc_action_slpc_set_param(guc, id, value);
 }
 
+static int slpc_unset_param(struct intel_guc_slpc *slpc,
+				u8 id)
+{
+	struct intel_guc *guc = slpc_to_guc(slpc);
+
+	GEM_BUG_ON(id >= SLPC_MAX_PARAM);
+
+	return guc_action_slpc_unset_param(guc, id);
+}
+
 static const char *slpc_state_string(struct intel_guc_slpc *slpc)
 {
 	const char *str = NULL;
@@ -388,6 +414,55 @@ void intel_guc_pm_intrmsk_enable(struct intel_gt *gt)
 			   GEN6_PMINTRMSK, pm_intrmsk_mbz, 0);
 }
 
+static int intel_guc_slpc_set_softlimits(struct intel_guc_slpc *slpc)
+{
+	int ret = 0;
+
+	/* Softlimits are initially equivalent to platform limits
+	 * unless they have deviated from defaults, in which case,
+	 * we retain the values and set min/max accordingly.
+	 */
+	if (!slpc->max_freq_softlimit)
+		slpc->max_freq_softlimit = slpc->rp0_freq;
+	else if (slpc->max_freq_softlimit != slpc->rp0_freq)
+		ret = intel_guc_slpc_set_max_freq(slpc,
+					slpc->max_freq_softlimit);
+
+	if (!slpc->min_freq_softlimit)
+		slpc->min_freq_softlimit = slpc->min_freq;
+	else if (slpc->min_freq_softlimit != slpc->min_freq)
+		ret = intel_guc_slpc_set_min_freq(slpc,
+					slpc->min_freq_softlimit);
+
+	return ret;
+}
+
+static void intel_guc_slpc_ignore_eff_freq(struct intel_guc_slpc *slpc, bool ignore)
+{
+	if (ignore) {
+		/* A failure here does not affect the algorithm in a fatal way */
+		slpc_set_param(slpc,
+		   SLPC_PARAM_IGNORE_EFFICIENT_FREQUENCY,
+		   ignore);
+		slpc_set_param(slpc,
+		   SLPC_PARAM_GLOBAL_MIN_GT_UNSLICE_FREQ_MHZ,
+		   slpc->min_freq);
+	} else {
+		slpc_unset_param(slpc,
+		   SLPC_PARAM_IGNORE_EFFICIENT_FREQUENCY);
+		slpc_unset_param(slpc,
+		   SLPC_PARAM_GLOBAL_MIN_GT_UNSLICE_FREQ_MHZ);
+	}
+}
+
+static void intel_guc_slpc_use_fused_rp0(struct intel_guc_slpc *slpc)
+{
+	/* Force slpc to used platform rp0 */
+	slpc_set_param(slpc,
+	   SLPC_PARAM_GLOBAL_MAX_GT_UNSLICE_FREQ_MHZ,
+	   slpc->rp0_freq);
+}
+
 /*
  * intel_guc_slpc_enable() - Start SLPC
  * @slpc: pointer to intel_guc_slpc.
@@ -405,6 +480,7 @@ int intel_guc_slpc_enable(struct intel_guc_slpc *slpc)
 {
 	struct drm_i915_private *i915 = slpc_to_i915(slpc);
 	struct slpc_shared_data *data;
+	u32 rp_state_cap;
 	int ret;
 
 	GEM_BUG_ON(!slpc->vma);
@@ -442,6 +518,28 @@ int intel_guc_slpc_enable(struct intel_guc_slpc *slpc)
 			slpc_decode_min_freq(slpc),
 			slpc_decode_max_freq(slpc));
 
+	rp_state_cap = intel_uncore_read(i915->gt.uncore, GEN6_RP_STATE_CAP);
+
+	slpc->rp0_freq = REG_FIELD_GET(RP0_CAP_MASK, rp_state_cap) *
+					GT_FREQUENCY_MULTIPLIER;
+	slpc->rp1_freq = REG_FIELD_GET(RP1_CAP_MASK, rp_state_cap) *
+					GT_FREQUENCY_MULTIPLIER;
+	slpc->min_freq = REG_FIELD_GET(RPN_CAP_MASK, rp_state_cap) *
+					GT_FREQUENCY_MULTIPLIER;
+
+	/* Ignore efficient freq and set min/max to platform min/max */
+	intel_guc_slpc_ignore_eff_freq(slpc, true);
+	intel_guc_slpc_use_fused_rp0(slpc);
+
+	ret = intel_guc_slpc_set_softlimits(slpc);
+	if (ret)
+		drm_err(&i915->drm, "Set softlimits returned (%pe)\n",
+					ERR_PTR(ret));
+
+	drm_info(&i915->drm,
+		 "Platform fused frequency values - min: %u Mhz, max: %u Mhz\n",
+		 slpc->min_freq,
+		 slpc->rp0_freq);
 
 	return 0;
 }
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc_types.h b/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc_types.h
index c417992b1346..8c42562a28fc 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc_types.h
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc_types.h
@@ -15,6 +15,15 @@ struct intel_guc_slpc {
 
 	struct i915_vma *vma;
 	struct slpc_shared_data *vaddr;
+
+	/* platform frequency limits */
+	u32 min_freq;
+	u32 rp0_freq;
+	u32 rp1_freq;
+
+	/* frequency softlimits */
+	u32 min_freq_softlimit;
+	u32 max_freq_softlimit;
 };
 
 #endif
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index aa433ae8f5de..92392c1da0e6 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -4086,6 +4086,9 @@ static inline bool i915_mmio_reg_valid(i915_reg_t reg)
 #define BXT_GT_PERF_STATUS      _MMIO(MCHBAR_MIRROR_BASE_SNB + 0x7070)
 #define GEN6_RP_STATE_LIMITS	_MMIO(MCHBAR_MIRROR_BASE_SNB + 0x5994)
 #define GEN6_RP_STATE_CAP	_MMIO(MCHBAR_MIRROR_BASE_SNB + 0x5998)
+#define   RP0_CAP_MASK		REG_GENMASK(7, 0)
+#define   RP1_CAP_MASK		REG_GENMASK(15, 8)
+#define   RPN_CAP_MASK		REG_GENMASK(23, 16)
 #define BXT_RP_STATE_CAP        _MMIO(0x138170)
 #define GEN9_RP_STATE_LIMITS	_MMIO(0x138148)
 
