drm/i915: Restore rps/rc6 on reset
A check of rps/rc6 state after i915_reset determined that the ring
MAX_IDLE registers were returned to their hardware defaults and that
the GEN6_PMIMR register was set to mask all interrupts. This change
restores those values to their pre-reset states by re-initializing
rps/rc6 in i915_reset. A full re-initialization was opted for versus
a targeted set of restore operations for simplicity and maintain-
ability. Note that the re-initialization is not done for Ironlake,
due to a past comment that it causes problems.
Also updated the rps initialization sequence to preserve existing
min/max values in the case of a re-init. We assume the values were
validated upon being set and do not do further range checking. The
debugfs interface for changing min/max was updated with range
checking to ensure this condition (already present in sysfs
interface).
v2: fix rps logging to output hw_max and hw_min, not rps.max_delay
and rps.min_delay which don't strictly represent hardware limits.
Add igt testcase to signed-off-by section.
Testcase: igt/pm_rps/reset
Signed-off-by: Jeff McGee <jeff.mcgee@intel.com>
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 9ab3883..6af58cd 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -3322,7 +3322,7 @@
{
struct drm_i915_private *dev_priv = dev->dev_private;
struct intel_ring_buffer *ring;
- u32 rp_state_cap;
+ u32 rp_state_cap, hw_max, hw_min;
u32 gt_perf_status;
u32 rc6vids, pcu_mbox, rc6_mask = 0;
u32 gtfifodbg;
@@ -3351,13 +3351,20 @@
gt_perf_status = I915_READ(GEN6_GT_PERF_STATUS);
/* In units of 50MHz */
- dev_priv->rps.hw_max = dev_priv->rps.max_delay = rp_state_cap & 0xff;
- dev_priv->rps.min_delay = (rp_state_cap >> 16) & 0xff;
+ dev_priv->rps.hw_max = hw_max = rp_state_cap & 0xff;
+ hw_min = (rp_state_cap >> 16) & 0xff;
dev_priv->rps.rp1_delay = (rp_state_cap >> 8) & 0xff;
dev_priv->rps.rp0_delay = (rp_state_cap >> 0) & 0xff;
dev_priv->rps.rpe_delay = dev_priv->rps.rp1_delay;
dev_priv->rps.cur_delay = 0;
+ /* Preserve min/max settings in case of re-init */
+ if (dev_priv->rps.max_delay == 0)
+ dev_priv->rps.max_delay = hw_max;
+
+ if (dev_priv->rps.min_delay == 0)
+ dev_priv->rps.min_delay = hw_min;
+
/* disable the counters and set deterministic thresholds */
I915_WRITE(GEN6_RC_CONTROL, 0);
@@ -3586,7 +3593,7 @@
{
struct drm_i915_private *dev_priv = dev->dev_private;
struct intel_ring_buffer *ring;
- u32 gtfifodbg, val, rc6_mode = 0;
+ u32 gtfifodbg, val, hw_max, hw_min, rc6_mode = 0;
int i;
WARN_ON(!mutex_is_locked(&dev_priv->rps.hw_lock));
@@ -3648,21 +3655,27 @@
vlv_gpu_freq(dev_priv, dev_priv->rps.cur_delay),
dev_priv->rps.cur_delay);
- dev_priv->rps.max_delay = valleyview_rps_max_freq(dev_priv);
- dev_priv->rps.hw_max = dev_priv->rps.max_delay;
+ dev_priv->rps.hw_max = hw_max = valleyview_rps_max_freq(dev_priv);
DRM_DEBUG_DRIVER("max GPU freq: %d MHz (%u)\n",
- vlv_gpu_freq(dev_priv, dev_priv->rps.max_delay),
- dev_priv->rps.max_delay);
+ vlv_gpu_freq(dev_priv, hw_max),
+ hw_max);
dev_priv->rps.rpe_delay = valleyview_rps_rpe_freq(dev_priv);
DRM_DEBUG_DRIVER("RPe GPU freq: %d MHz (%u)\n",
vlv_gpu_freq(dev_priv, dev_priv->rps.rpe_delay),
dev_priv->rps.rpe_delay);
- dev_priv->rps.min_delay = valleyview_rps_min_freq(dev_priv);
+ hw_min = valleyview_rps_min_freq(dev_priv);
DRM_DEBUG_DRIVER("min GPU freq: %d MHz (%u)\n",
- vlv_gpu_freq(dev_priv, dev_priv->rps.min_delay),
- dev_priv->rps.min_delay);
+ vlv_gpu_freq(dev_priv, hw_min),
+ hw_min);
+
+ /* Preserve min/max settings in case of re-init */
+ if (dev_priv->rps.max_delay == 0)
+ dev_priv->rps.max_delay = hw_max;
+
+ if (dev_priv->rps.min_delay == 0)
+ dev_priv->rps.min_delay = hw_min;
DRM_DEBUG_DRIVER("setting GPU freq to %d MHz (%u)\n",
vlv_gpu_freq(dev_priv, dev_priv->rps.rpe_delay),