drm/i915: Don't multiply the watermark latency values too early
The LP1+ watermark latency values need to be multiplied by 5 to
make them suitable for watermark calculations. However on pre-HSW
platforms we're going to need the raw value later when we have to
write it to the WM_LPn registers' latency field. So delay the
multiplication until it's needed.
Note: Paulo complains that the units of wm (now in 100ns) aren't
really clear and I agree. But that can be fixed later on ...
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
[danvet: Add a comment about the unit obfuscation.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index b8ec143..b6430ba 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -2361,10 +2361,10 @@
wm[0] = (sskpd >> 56) & 0xFF;
if (wm[0] == 0)
wm[0] = sskpd & 0xF;
- wm[1] = ((sskpd >> 4) & 0xFF) * 5;
- wm[2] = ((sskpd >> 12) & 0xFF) * 5;
- wm[3] = ((sskpd >> 20) & 0x1FF) * 5;
- wm[4] = ((sskpd >> 32) & 0x1FF) * 5;
+ wm[1] = (sskpd >> 4) & 0xFF;
+ wm[2] = (sskpd >> 12) & 0xFF;
+ wm[3] = (sskpd >> 20) & 0x1FF;
+ wm[4] = (sskpd >> 32) & 0x1FF;
}
}
@@ -2442,7 +2442,7 @@
int level, max_level, wm_lp;
for (level = 1; level <= 4; level++)
- if (!hsw_compute_lp_wm(wm[level], lp_maximums, params,
+ if (!hsw_compute_lp_wm(wm[level] * 5, lp_maximums, params,
&lp_results[level - 1]))
break;
max_level = level - 1;