drm/i915/rps: Freq caps for MTL

For MTL, when reading from HW, RP0, RP1 (actuall RPe) and RPn freq use an
entirely different set of registers with different fields, bitwidths and
units.

v2: Move MTL check into a separate function (Jani)

Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Badal Nilawar <badal.nilawar@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220910143844.1755324-4-ashutosh.dixit@intel.com

drivers/gpu/drm/i915/gt/intel_rps.c

@@ -1085,15 +1085,25 @@ static u32 intel_rps_read_state_cap(struct intel_rps *rps)
 		return intel_uncore_read(uncore, GEN6_RP_STATE_CAP);
 }
 
-/**
- * gen6_rps_get_freq_caps - Get freq caps exposed by HW
- * @rps: the intel_rps structure
- * @caps: returned freq caps
- *
- * Returned "caps" frequencies should be converted to MHz using
- * intel_gpu_freq()
- */
-void gen6_rps_get_freq_caps(struct intel_rps *rps, struct intel_rps_freq_caps *caps)
+static void
+mtl_get_freq_caps(struct intel_rps *rps, struct intel_rps_freq_caps *caps)
+{
+	struct intel_uncore *uncore = rps_to_uncore(rps);
+	u32 rp_state_cap = rps_to_gt(rps)->type == GT_MEDIA ?
+				intel_uncore_read(uncore, MTL_MEDIAP_STATE_CAP) :
+				intel_uncore_read(uncore, MTL_RP_STATE_CAP);
+	u32 rpe = rps_to_gt(rps)->type == GT_MEDIA ?
+			intel_uncore_read(uncore, MTL_MPE_FREQUENCY) :
+			intel_uncore_read(uncore, MTL_GT_RPE_FREQUENCY);
+
+	/* MTL values are in units of 16.67 MHz */
+	caps->rp0_freq = REG_FIELD_GET(MTL_RP0_CAP_MASK, rp_state_cap);
+	caps->min_freq = REG_FIELD_GET(MTL_RPN_CAP_MASK, rp_state_cap);
+	caps->rp1_freq = REG_FIELD_GET(MTL_RPE_MASK, rpe);
+}
+
+static void
+__gen6_rps_get_freq_caps(struct intel_rps *rps, struct intel_rps_freq_caps *caps)
 {
 	struct drm_i915_private *i915 = rps_to_i915(rps);
 	u32 rp_state_cap;
@@ -1128,6 +1138,24 @@ void gen6_rps_get_freq_caps(struct intel_rps *rps, struct intel_rps_freq_caps *c
 	}
 }
 
+/**
+ * gen6_rps_get_freq_caps - Get freq caps exposed by HW
+ * @rps: the intel_rps structure
+ * @caps: returned freq caps
+ *
+ * Returned "caps" frequencies should be converted to MHz using
+ * intel_gpu_freq()
+ */
+void gen6_rps_get_freq_caps(struct intel_rps *rps, struct intel_rps_freq_caps *caps)
+{
+	struct drm_i915_private *i915 = rps_to_i915(rps);
+
+	if (IS_METEORLAKE(i915))
+		return mtl_get_freq_caps(rps, caps);
+	else
+		return __gen6_rps_get_freq_caps(rps, caps);
+}
+
 static void gen6_rps_init(struct intel_rps *rps)
 {
 	struct drm_i915_private *i915 = rps_to_i915(rps);

drivers/gpu/drm/i915/i915_reg.h

@@ -1856,6 +1856,15 @@
 #define XEHPSDV_RP_STATE_CAP	_MMIO(0x250014)
 #define PVC_RP_STATE_CAP	_MMIO(0x281014)
 
+#define MTL_RP_STATE_CAP	_MMIO(0x138000)
+#define MTL_MEDIAP_STATE_CAP	_MMIO(0x138020)
+#define   MTL_RP0_CAP_MASK	REG_GENMASK(8, 0)
+#define   MTL_RPN_CAP_MASK	REG_GENMASK(24, 16)
+
+#define MTL_GT_RPE_FREQUENCY	_MMIO(0x13800c)
+#define MTL_MPE_FREQUENCY	_MMIO(0x13802c)
+#define   MTL_RPE_MASK		REG_GENMASK(8, 0)
+
 #define GT0_PERF_LIMIT_REASONS		_MMIO(0x1381a8)
 #define   GT0_PERF_LIMIT_REASONS_MASK	0xde3
 #define   PROCHOT_MASK			REG_BIT(0)