drm/i915/gt: Add media RP0/RPn to per-gt sysfs

Retrieve RP0 and RPn freq for media IP from PCODE and display in per-gt
sysfs. This patch adds the following files to gt/gtN sysfs:
* media_RP0_freq_mhz
* media_RPn_freq_mhz

v2: Fixed commit author (Rodrigo)
v3: Convert to new uncore interface for pcode functions
v4: Adapt to intel_pcode.* function rename
v5: #include "intel_pcode.h" in alphabetical order (Tvrtko)

Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: Dale B Stimson <dale.b.stimson@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/45e34127a79e808f6582db8afb77f2f728a446e6.1653484574.git.ashutosh.dixit@intel.com

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

@@ -14,6 +14,7 @@
 #include "intel_gt_regs.h"
 #include "intel_gt_sysfs.h"
 #include "intel_gt_sysfs_pm.h"
+#include "intel_pcode.h"
 #include "intel_rc6.h"
 #include "intel_rps.h"
 
@@ -670,13 +671,59 @@ static ssize_t media_freq_factor_store(struct device *dev,
 	return err ?: count;
 }
 
+static ssize_t media_RP0_freq_mhz_show(struct device *dev,
+				       struct device_attribute *attr,
+				       char *buff)
+{
+	struct intel_gt *gt = intel_gt_sysfs_get_drvdata(dev, attr->attr.name);
+	u32 val;
+	int err;
+
+	err = snb_pcode_read_p(gt->uncore, XEHPSDV_PCODE_FREQUENCY_CONFIG,
+			       PCODE_MBOX_FC_SC_READ_FUSED_P0,
+			       PCODE_MBOX_DOMAIN_MEDIAFF, &val);
+
+	if (err)
+		return err;
+
+	/* Fused media RP0 read from pcode is in units of 50 MHz */
+	val *= GT_FREQUENCY_MULTIPLIER;
+
+	return sysfs_emit(buff, "%u\n", val);
+}
+
+static ssize_t media_RPn_freq_mhz_show(struct device *dev,
+				       struct device_attribute *attr,
+				       char *buff)
+{
+	struct intel_gt *gt = intel_gt_sysfs_get_drvdata(dev, attr->attr.name);
+	u32 val;
+	int err;
+
+	err = snb_pcode_read_p(gt->uncore, XEHPSDV_PCODE_FREQUENCY_CONFIG,
+			       PCODE_MBOX_FC_SC_READ_FUSED_PN,
+			       PCODE_MBOX_DOMAIN_MEDIAFF, &val);
+
+	if (err)
+		return err;
+
+	/* Fused media RPn read from pcode is in units of 50 MHz */
+	val *= GT_FREQUENCY_MULTIPLIER;
+
+	return sysfs_emit(buff, "%u\n", val);
+}
+
 static DEVICE_ATTR_RW(media_freq_factor);
 static struct device_attribute dev_attr_media_freq_factor_scale =
 	__ATTR(media_freq_factor.scale, 0444, freq_factor_scale_show, NULL);
+static DEVICE_ATTR_RO(media_RP0_freq_mhz);
+static DEVICE_ATTR_RO(media_RPn_freq_mhz);
 
 static const struct attribute *media_perf_power_attrs[] = {
 	&dev_attr_media_freq_factor.attr,
 	&dev_attr_media_freq_factor_scale.attr,
+	&dev_attr_media_RP0_freq_mhz.attr,
+	&dev_attr_media_RPn_freq_mhz.attr,
 	NULL
 };
 

drivers/gpu/drm/i915/i915_reg.h

@@ -6767,6 +6767,14 @@
 #define     DG1_UNCORE_GET_INIT_STATUS		0x0
 #define     DG1_UNCORE_INIT_STATUS_COMPLETE	0x1
 #define GEN12_PCODE_READ_SAGV_BLOCK_TIME_US	0x23
+#define   XEHPSDV_PCODE_FREQUENCY_CONFIG		0x6e	/* xehpsdv, pvc */
+/* XEHPSDV_PCODE_FREQUENCY_CONFIG sub-commands (param1) */
+#define     PCODE_MBOX_FC_SC_READ_FUSED_P0	0x0
+#define     PCODE_MBOX_FC_SC_READ_FUSED_PN	0x1
+/* PCODE_MBOX_DOMAIN_* - mailbox domain IDs */
+/*   XEHPSDV_PCODE_FREQUENCY_CONFIG param2 */
+#define     PCODE_MBOX_DOMAIN_NONE		0x0
+#define     PCODE_MBOX_DOMAIN_MEDIAFF		0x3
 #define GEN6_PCODE_DATA				_MMIO(0x138128)
 #define   GEN6_PCODE_FREQ_IA_RATIO_SHIFT	8
 #define   GEN6_PCODE_FREQ_RING_RATIO_SHIFT	16