[Intel-gfx] [PATCH] drm/i915/slpc: Fix PCODE IA Freq requests when using SLPC

[Rodrigo Vivi]

We need to inform PCODE of a desired ring frequencies so PCODE update
the memory frequencies to us. rps->min_freq and rps->max_freq are the
frequencies used in that request. However they were unset when SLPC was
enabled and PCODE never updated the memory freq.

v2 (as Suggested by Ashutosh): if SLPC is in use, let's pick the right
   frequencies from the get_ia_constants instead of the fake init of
   rps' min and max.

v3: don't forget the max <= min return

Fixes: 7ba79a671568 ("drm/i915/guc/slpc: Gate Host RPS when SLPC is enabled")
Cc: <stable at vger.kernel.org> # v5.15+
Cc: Ashutosh Dixit <ashutosh.dixit at intel.com>
Tested-by: Sushma Venkatesh Reddy <sushma.venkatesh.reddy at intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
---
 drivers/gpu/drm/i915/gt/intel_llc.c | 24 ++++++++++++++++--------
 1 file changed, 16 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_llc.c b/drivers/gpu/drm/i915/gt/intel_llc.c
index 14fe65812e42..2677d62573d9 100644
--- a/drivers/gpu/drm/i915/gt/intel_llc.c
+++ b/drivers/gpu/drm/i915/gt/intel_llc.c
@@ -49,13 +49,28 @@ static unsigned int cpu_max_MHz(void)
 static bool get_ia_constants(struct intel_llc *llc,
 			     struct ia_constants *consts)
 {
+	struct intel_guc_slpc *slpc = &llc_to_gt(llc)->uc.guc.slpc;
 	struct drm_i915_private *i915 = llc_to_gt(llc)->i915;
 	struct intel_rps *rps = &llc_to_gt(llc)->rps;
 
 	if (!HAS_LLC(i915) || IS_DGFX(i915))
 		return false;
 
-	if (rps->max_freq <= rps->min_freq)
+	if (intel_uc_uses_guc_slpc(&llc_to_gt(llc)->uc)) {
+		consts->min_gpu_freq = slpc->min_freq;
+		consts->max_gpu_freq = slpc->rp0_freq;
+	} else {
+		consts->min_gpu_freq = rps->min_freq;
+		consts->max_gpu_freq = rps->max_freq;
+	}
+
+	if (GRAPHICS_VER(i915) >= 9) {
+		/* Convert GT frequency to 50 HZ units */
+		consts->min_gpu_freq /= GEN9_FREQ_SCALER;
+		consts->max_gpu_freq /= GEN9_FREQ_SCALER;
+	}
+
+	if (consts->max_gpu_freq <= consts->min_gpu_freq)
 		return false;
 
 	consts->max_ia_freq = cpu_max_MHz();
@@ -65,13 +80,6 @@ static bool get_ia_constants(struct intel_llc *llc,
 	/* convert DDR frequency from units of 266.6MHz to bandwidth */
 	consts->min_ring_freq = mult_frac(consts->min_ring_freq, 8, 3);
 
-	consts->min_gpu_freq = rps->min_freq;
-	consts->max_gpu_freq = rps->max_freq;
-	if (GRAPHICS_VER(i915) >= 9) {
-		/* Convert GT frequency to 50 HZ units */
-		consts->min_gpu_freq /= GEN9_FREQ_SCALER;
-		consts->max_gpu_freq /= GEN9_FREQ_SCALER;
-	}
 
 	return true;
 }
-- 
2.37.1