[Intel-gfx] [PATCH v3] drm/i915: Add TigerLake bandwidth checking

[Stanislav Lisovskiy]

Added bandwidth calculation algorithm and checks,
similar way as it was done for ICL, some constants
were corrected according to BSpec.

Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy at intel.com>

v2: Start using same icl_get_bw_info function to avoid
    code duplication. Moved mpagesize to memory info
    related structure as it is now dependant on memory type.
    Fixed qi.t_bl field assignment.

v3: Removed mpagesize as unused. Duplicate code and redundant blankline
    fixed.

Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=111600
---
 drivers/gpu/drm/i915/display/intel_bw.c | 25 ++++++++++++++++++-------
 1 file changed, 18 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_bw.c b/drivers/gpu/drm/i915/display/intel_bw.c
index 688858ebe4d0..7080ec73d33c 100644
--- a/drivers/gpu/drm/i915/display/intel_bw.c
+++ b/drivers/gpu/drm/i915/display/intel_bw.c
@@ -56,7 +56,11 @@ static int icl_pcode_read_mem_global_info(struct drm_i915_private *dev_priv,
 	qi->num_channels = (val & 0xf0) >> 4;
 	qi->num_points = (val & 0xf00) >> 8;
 
-	qi->t_bl = qi->dram_type == INTEL_DRAM_DDR4 ? 4 : 8;
+	if (IS_GEN(dev_priv, 11)) {
+		qi->t_bl = qi->dram_type == INTEL_DRAM_DDR4 ? 4 : 8;
+	} else if (IS_GEN(dev_priv, 12)) {
+		qi->t_bl = qi->dram_type == INTEL_DRAM_DDR4 ? 4 : 16;
+	}
 
 	return 0;
 }
@@ -132,20 +136,25 @@ static int icl_sagv_max_dclk(const struct intel_qgv_info *qi)
 }
 
 struct intel_sa_info {
-	u8 deburst, mpagesize, deprogbwlimit, displayrtids;
+	u16 displayrtids;
+	u8 deburst, deprogbwlimit;
 };
 
 static const struct intel_sa_info icl_sa_info = {
 	.deburst = 8,
-	.mpagesize = 16,
 	.deprogbwlimit = 25, /* GB/s */
 	.displayrtids = 128,
 };
 
-static int icl_get_bw_info(struct drm_i915_private *dev_priv)
+static const struct intel_sa_info tgl_sa_info = {
+	.deburst = 16,
+	.deprogbwlimit = 34, /* GB/s */
+	.displayrtids = 256,
+};
+
+static int icl_get_bw_info(struct drm_i915_private *dev_priv, const struct intel_sa_info *sa)
 {
 	struct intel_qgv_info qi = {};
-	const struct intel_sa_info *sa = &icl_sa_info;
 	bool is_y_tile = true; /* assume y tile may be used */
 	int num_channels;
 	int deinterleave;
@@ -234,13 +243,15 @@ static unsigned int icl_max_bw(struct drm_i915_private *dev_priv,
 void intel_bw_init_hw(struct drm_i915_private *dev_priv)
 {
 	if (IS_GEN(dev_priv, 11))
-		icl_get_bw_info(dev_priv);
+		icl_get_bw_info(dev_priv, &icl_sa_info);
+	else if (IS_GEN(dev_priv, 12))
+		icl_get_bw_info(dev_priv, &tgl_sa_info);
 }
 
 static unsigned int intel_max_data_rate(struct drm_i915_private *dev_priv,
 					int num_planes)
 {
-	if (IS_GEN(dev_priv, 11))
+	if (IS_GEN(dev_priv, 11) || IS_GEN(dev_priv, 12))
 		/*
 		 * FIXME with SAGV disabled maybe we can assume
 		 * point 1 will always be used? Seems to match
-- 
2.17.1