[PATCH] drm/i915: clear the QGV mask set by GOP while booting

[george.d.sworo at intel.com]

From: George D Sworo <george.d.sworo at intel.com>

GOP driver in the firmware is masking the QGV points except the one
which can
provide high Bandwidth required for panel.

On boot to the OS the mask is already set, and is not cleared anywhere
in the i915 driver
even though sagv is enabled. This means Pcode is unable to switch to
other QGV work points
except the one enabled by default in the GOP driver at boot time.

This change resets the mask, when i915 driver is finding the QGV
points at the boot time. So that Pcode can switch to QGV work points
based
on the Workloads.

Signed-off-by: George D Sworo <george.d.sworo at intel.com>
---
 drivers/gpu/drm/i915/display/intel_bw.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_bw.c b/drivers/gpu/drm/i915/display/intel_bw.c
index bef96db62c80..e2576c0fb729 100644
--- a/drivers/gpu/drm/i915/display/intel_bw.c
+++ b/drivers/gpu/drm/i915/display/intel_bw.c
@@ -212,6 +212,7 @@ static int icl_get_qgv_points(struct drm_i915_private *dev_priv,
 			      bool is_y_tile)
 {
 	const struct dram_info *dram_info = &dev_priv->dram_info;
+	u32 val = 0x00, val2 = 0;
 	int i, ret;
 
 	qi->num_points = dram_info->num_qgv_points;
@@ -311,6 +312,11 @@ static int icl_get_qgv_points(struct drm_i915_private *dev_priv,
 				    i, qi->psf_points[i].clk);
 	}
 
+	/* clear the QGV points mask set by the GOP driver while booting */
+	ret = snb_pcode_read(&dev_priv->uncore, ICL_PCODE_SAGV_DE_MEM_SS_CONFIG, &val, &val2);
+	if (ret)
+		return ret;
+
 	return 0;
 }
 
-- 
2.34.1