[Intel-gfx] [PATCH 3/5] drm/i915: WA for zero memory channel

[José Roberto de Souza]

Commit c457d9cf256e ("drm/i915: Make sure we have enough memory
bandwidth on ICL") assumes that we always have a non-zero
dram_info->channels and uses it as a divisor.
We need num memory channels to be at least 1 for sane bw limits
checking, even when PCode returns 0 or there is a error reading it, so
lets force it to 1 in this case.

Cc: Stanislav Lisovskiy <stanislav.lisovskiy at intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi at intel.com>
Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
---
 drivers/gpu/drm/i915/display/intel_bw.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/display/intel_bw.c b/drivers/gpu/drm/i915/display/intel_bw.c
index 3a1ba52266a7..bfb398f0432e 100644
--- a/drivers/gpu/drm/i915/display/intel_bw.c
+++ b/drivers/gpu/drm/i915/display/intel_bw.c
@@ -162,7 +162,7 @@ static int icl_get_bw_info(struct drm_i915_private *dev_priv, const struct intel
 {
 	struct intel_qgv_info qi = {};
 	bool is_y_tile = true; /* assume y tile may be used */
-	int num_channels = dev_priv->dram_info.num_channels;
+	int num_channels = max_t(u8, 1, dev_priv->dram_info.num_channels);
 	int deinterleave;
 	int ipqdepth, ipqdepthpch;
 	int dclk_max;
-- 
2.31.1