[Intel-gfx] [PATCH v10 6/6] drm/i915/tgl: Add DC3CO counter in i915_dmc_info

[Anshuman Gupta]

Adding DC3CO counter in i915_dmc_info debugfs will be
useful for DC3CO validation.
DMC firmware uses DMC_DEBUG3 register as DC3CO counter
register on TGL, as per B.Specs DMC_DEBUG3 is general
purpose register.

v1: comment modification for DMC_DBUG3.
    using GEN >= 12 check instead of IS_TIGERLAKE()
    to print DMC_DEBUG3 counter value.

Cc: Jani Nikula <jani.nikula at intel.com>
Cc: Imre Deak <imre.deak at intel.com>
Cc: Animesh Manna <animesh.manna at intel.com>
Signed-off-by: Anshuman Gupta <anshuman.gupta at intel.com>
---
 drivers/gpu/drm/i915/i915_debugfs.c | 7 +++++++
 drivers/gpu/drm/i915/i915_reg.h     | 2 ++
 2 files changed, 9 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index b5b449a88cf1..fcccfd4507bd 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -2410,6 +2410,13 @@ static int i915_dmc_info(struct seq_file *m, void *unused)
 	if (INTEL_GEN(dev_priv) >= 12) {
 		dc5_reg = TGL_DMC_DEBUG_DC5_COUNT;
 		dc6_reg = TGL_DMC_DEBUG_DC6_COUNT;
+		/*
+		 * NOTE: DMC_DEBUG3 is a general purpose reg.
+		 * According to B.Specs:49196 DMC f/w reuses DC5/6 counter
+		 * reg for DC3CO debugging and validation,
+		 * but TGL DMC f/w is using DMC_DEBUG3 reg for DC3CO counter.
+		 */
+		seq_printf(m, "DC3CO count: %d\n", I915_READ(DMC_DEBUG3));
 	} else {
 		dc5_reg = IS_BROXTON(dev_priv) ? BXT_CSR_DC3_DC5_COUNT :
 						 SKL_CSR_DC3_DC5_COUNT;
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 3ee9720af207..af810f6ed652 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -7263,6 +7263,8 @@ enum {
 #define TGL_DMC_DEBUG_DC5_COUNT	_MMIO(0x101084)
 #define TGL_DMC_DEBUG_DC6_COUNT	_MMIO(0x101088)
 
+#define DMC_DEBUG3		_MMIO(0x101090)
+
 /* interrupts */
 #define DE_MASTER_IRQ_CONTROL   (1 << 31)
 #define DE_SPRITEB_FLIP_DONE    (1 << 29)
-- 
2.21.0