drm/i915: cleanup rc6 code
[firefly-linux-kernel-4.4.55.git] / drivers / gpu / drm / i915 / intel_display.c
index 9d97fd4e5558f8fc3f409872250ba0524f97c3ba..1190efa390bdc7f439bfd352b7554a73f8bd65b5 100644 (file)
@@ -3418,9 +3418,9 @@ static void i830_update_wm(struct drm_device *dev, int planea_clock, int unused,
 static bool ironlake_compute_wm0(struct drm_device *dev,
                                 int pipe,
                                 const struct intel_watermark_params *display,
-                                int display_latency,
+                                int display_latency_ns,
                                 const struct intel_watermark_params *cursor,
-                                int cursor_latency,
+                                int cursor_latency_ns,
                                 int *plane_wm,
                                 int *cursor_wm)
 {
@@ -3438,7 +3438,7 @@ static bool ironlake_compute_wm0(struct drm_device *dev,
        pixel_size = crtc->fb->bits_per_pixel / 8;
 
        /* Use the small buffer method to calculate plane watermark */
-       entries = ((clock * pixel_size / 1000) * display_latency * 100) / 1000;
+       entries = ((clock * pixel_size / 1000) * display_latency_ns) / 1000;
        entries = DIV_ROUND_UP(entries, display->cacheline_size);
        *plane_wm = entries + display->guard_size;
        if (*plane_wm > (int)display->max_wm)
@@ -3446,7 +3446,7 @@ static bool ironlake_compute_wm0(struct drm_device *dev,
 
        /* Use the large buffer method to calculate cursor watermark */
        line_time_us = ((htotal * 1000) / clock);
-       line_count = (cursor_latency * 100 / line_time_us + 1000) / 1000;
+       line_count = (cursor_latency_ns / line_time_us + 1000) / 1000;
        entries = line_count * 64 * pixel_size;
        entries = DIV_ROUND_UP(entries, cursor->cacheline_size);
        *cursor_wm = entries + cursor->guard_size;
@@ -3456,113 +3456,17 @@ static bool ironlake_compute_wm0(struct drm_device *dev,
        return true;
 }
 
-static void ironlake_update_wm(struct drm_device *dev,
-                              int planea_clock, int planeb_clock,
-                              int sr_hdisplay, int sr_htotal,
-                              int pixel_size)
-{
-       struct drm_i915_private *dev_priv = dev->dev_private;
-       int plane_wm, cursor_wm, enabled;
-       int tmp;
-
-       enabled = 0;
-       if (ironlake_compute_wm0(dev, 0,
-                                &ironlake_display_wm_info,
-                                ILK_LP0_PLANE_LATENCY,
-                                &ironlake_cursor_wm_info,
-                                ILK_LP0_CURSOR_LATENCY,
-                                &plane_wm, &cursor_wm)) {
-               I915_WRITE(WM0_PIPEA_ILK,
-                          (plane_wm << WM0_PIPE_PLANE_SHIFT) | cursor_wm);
-               DRM_DEBUG_KMS("FIFO watermarks For pipe A -"
-                             " plane %d, " "cursor: %d\n",
-                             plane_wm, cursor_wm);
-               enabled++;
-       }
-
-       if (ironlake_compute_wm0(dev, 1,
-                                &ironlake_display_wm_info,
-                                ILK_LP0_PLANE_LATENCY,
-                                &ironlake_cursor_wm_info,
-                                ILK_LP0_CURSOR_LATENCY,
-                                &plane_wm, &cursor_wm)) {
-               I915_WRITE(WM0_PIPEB_ILK,
-                          (plane_wm << WM0_PIPE_PLANE_SHIFT) | cursor_wm);
-               DRM_DEBUG_KMS("FIFO watermarks For pipe B -"
-                             " plane %d, cursor: %d\n",
-                             plane_wm, cursor_wm);
-               enabled++;
-       }
-
-       /*
-        * Calculate and update the self-refresh watermark only when one
-        * display plane is used.
-        */
-       tmp = 0;
-       if (enabled == 1) {
-               unsigned long line_time_us;
-               int small, large, plane_fbc;
-               int sr_clock, entries;
-               int line_count, line_size;
-               /* Read the self-refresh latency. The unit is 0.5us */
-               int ilk_sr_latency = I915_READ(MLTR_ILK) & ILK_SRLT_MASK;
-
-               sr_clock = planea_clock ? planea_clock : planeb_clock;
-               line_time_us = (sr_htotal * 1000) / sr_clock;
-
-               /* Use ns/us then divide to preserve precision */
-               line_count = ((ilk_sr_latency * 500) / line_time_us + 1000)
-                       / 1000;
-               line_size = sr_hdisplay * pixel_size;
-
-               /* Use the minimum of the small and large buffer method for primary */
-               small = ((sr_clock * pixel_size / 1000) * (ilk_sr_latency * 500)) / 1000;
-               large = line_count * line_size;
-
-               entries = DIV_ROUND_UP(min(small, large),
-                                      ironlake_display_srwm_info.cacheline_size);
-
-               plane_fbc = entries * 64;
-               plane_fbc = DIV_ROUND_UP(plane_fbc, line_size);
-
-               plane_wm = entries + ironlake_display_srwm_info.guard_size;
-               if (plane_wm > (int)ironlake_display_srwm_info.max_wm)
-                       plane_wm = ironlake_display_srwm_info.max_wm;
-
-               /* calculate the self-refresh watermark for display cursor */
-               entries = line_count * pixel_size * 64;
-               entries = DIV_ROUND_UP(entries,
-                                      ironlake_cursor_srwm_info.cacheline_size);
-
-               cursor_wm = entries + ironlake_cursor_srwm_info.guard_size;
-               if (cursor_wm > (int)ironlake_cursor_srwm_info.max_wm)
-                       cursor_wm = ironlake_cursor_srwm_info.max_wm;
-
-               /* configure watermark and enable self-refresh */
-               tmp = (WM1_LP_SR_EN |
-                      (ilk_sr_latency << WM1_LP_LATENCY_SHIFT) |
-                      (plane_fbc << WM1_LP_FBC_SHIFT) |
-                      (plane_wm << WM1_LP_SR_SHIFT) |
-                      cursor_wm);
-               DRM_DEBUG_KMS("self-refresh watermark: display plane %d, fbc lines %d,"
-                             " cursor %d\n", plane_wm, plane_fbc, cursor_wm);
-       }
-       I915_WRITE(WM1_LP_ILK, tmp);
-       /* XXX setup WM2 and WM3 */
-}
-
 /*
  * Check the wm result.
  *
  * If any calculated watermark values is larger than the maximum value that
  * can be programmed into the associated watermark register, that watermark
  * must be disabled.
- *
- * Also return true if all of those watermark values is 0, which is set by
- * sandybridge_compute_srwm, to indicate the latency is ZERO.
  */
-static bool sandybridge_check_srwm(struct drm_device *dev, int level,
-                                  int fbc_wm, int display_wm, int cursor_wm)
+static bool ironlake_check_srwm(struct drm_device *dev, int level,
+                               int fbc_wm, int display_wm, int cursor_wm,
+                               const struct intel_watermark_params *display,
+                               const struct intel_watermark_params *cursor)
 {
        struct drm_i915_private *dev_priv = dev->dev_private;
 
@@ -3571,7 +3475,7 @@ static bool sandybridge_check_srwm(struct drm_device *dev, int level,
 
        if (fbc_wm > SNB_FBC_MAX_SRWM) {
                DRM_DEBUG_KMS("fbc watermark(%d) is too large(%d), disabling wm%d+\n",
-                               fbc_wm, SNB_FBC_MAX_SRWM, level);
+                             fbc_wm, SNB_FBC_MAX_SRWM, level);
 
                /* fbc has it's own way to disable FBC WM */
                I915_WRITE(DISP_ARB_CTL,
@@ -3579,15 +3483,15 @@ static bool sandybridge_check_srwm(struct drm_device *dev, int level,
                return false;
        }
 
-       if (display_wm > SNB_DISPLAY_MAX_SRWM) {
+       if (display_wm > display->max_wm) {
                DRM_DEBUG_KMS("display watermark(%d) is too large(%d), disabling wm%d+\n",
-                               display_wm, SNB_DISPLAY_MAX_SRWM, level);
+                             display_wm, SNB_DISPLAY_MAX_SRWM, level);
                return false;
        }
 
-       if (cursor_wm > SNB_CURSOR_MAX_SRWM) {
+       if (cursor_wm > cursor->max_wm) {
                DRM_DEBUG_KMS("cursor watermark(%d) is too large(%d), disabling wm%d+\n",
-                               cursor_wm, SNB_CURSOR_MAX_SRWM, level);
+                             cursor_wm, SNB_CURSOR_MAX_SRWM, level);
                return false;
        }
 
@@ -3602,16 +3506,18 @@ static bool sandybridge_check_srwm(struct drm_device *dev, int level,
 /*
  * Compute watermark values of WM[1-3],
  */
-static bool sandybridge_compute_srwm(struct drm_device *dev, int level,
-                                    int hdisplay, int htotal, int pixel_size,
-                                    int clock, int latency_ns, int *fbc_wm,
-                                    int *display_wm, int *cursor_wm)
+static bool ironlake_compute_srwm(struct drm_device *dev, int level,
+                                 int hdisplay, int htotal,
+                                 int pixel_size, int clock, int latency_ns,
+                                 const struct intel_watermark_params *display,
+                                 const struct intel_watermark_params *cursor,
+                                 int *fbc_wm, int *display_wm, int *cursor_wm)
 {
 
        unsigned long line_time_us;
+       int line_count, line_size;
        int small, large;
        int entries;
-       int line_count, line_size;
 
        if (!latency_ns) {
                *fbc_wm = *display_wm = *cursor_wm = 0;
@@ -3626,24 +3532,110 @@ static bool sandybridge_compute_srwm(struct drm_device *dev, int level,
        small = ((clock * pixel_size / 1000) * latency_ns) / 1000;
        large = line_count * line_size;
 
-       entries = DIV_ROUND_UP(min(small, large),
-                               sandybridge_display_srwm_info.cacheline_size);
-       *display_wm = entries + sandybridge_display_srwm_info.guard_size;
+       entries = DIV_ROUND_UP(min(small, large), display->cacheline_size);
+       *display_wm = entries + display->guard_size;
 
        /*
-        * Spec said:
+        * Spec says:
         * FBC WM = ((Final Primary WM * 64) / number of bytes per line) + 2
         */
        *fbc_wm = DIV_ROUND_UP(*display_wm * 64, line_size) + 2;
 
        /* calculate the self-refresh watermark for display cursor */
        entries = line_count * pixel_size * 64;
-       entries = DIV_ROUND_UP(entries,
-                              sandybridge_cursor_srwm_info.cacheline_size);
-       *cursor_wm = entries + sandybridge_cursor_srwm_info.guard_size;
+       entries = DIV_ROUND_UP(entries, cursor->cacheline_size);
+       *cursor_wm = entries + cursor->guard_size;
+
+       return ironlake_check_srwm(dev, level,
+                                  *fbc_wm, *display_wm, *cursor_wm,
+                                  display, cursor);
+}
+
+static void ironlake_update_wm(struct drm_device *dev,
+                              int planea_clock, int planeb_clock,
+                              int hdisplay, int htotal,
+                              int pixel_size)
+{
+       struct drm_i915_private *dev_priv = dev->dev_private;
+       int fbc_wm, plane_wm, cursor_wm, enabled;
+       int clock;
+
+       enabled = 0;
+       if (ironlake_compute_wm0(dev, 0,
+                                &ironlake_display_wm_info,
+                                ILK_LP0_PLANE_LATENCY,
+                                &ironlake_cursor_wm_info,
+                                ILK_LP0_CURSOR_LATENCY,
+                                &plane_wm, &cursor_wm)) {
+               I915_WRITE(WM0_PIPEA_ILK,
+                          (plane_wm << WM0_PIPE_PLANE_SHIFT) | cursor_wm);
+               DRM_DEBUG_KMS("FIFO watermarks For pipe A -"
+                             " plane %d, " "cursor: %d\n",
+                             plane_wm, cursor_wm);
+               enabled++;
+       }
+
+       if (ironlake_compute_wm0(dev, 1,
+                                &ironlake_display_wm_info,
+                                ILK_LP0_PLANE_LATENCY,
+                                &ironlake_cursor_wm_info,
+                                ILK_LP0_CURSOR_LATENCY,
+                                &plane_wm, &cursor_wm)) {
+               I915_WRITE(WM0_PIPEB_ILK,
+                          (plane_wm << WM0_PIPE_PLANE_SHIFT) | cursor_wm);
+               DRM_DEBUG_KMS("FIFO watermarks For pipe B -"
+                             " plane %d, cursor: %d\n",
+                             plane_wm, cursor_wm);
+               enabled++;
+       }
 
-       return sandybridge_check_srwm(dev, level,
-                                     *fbc_wm, *display_wm, *cursor_wm);
+       /*
+        * Calculate and update the self-refresh watermark only when one
+        * display plane is used.
+        */
+       I915_WRITE(WM3_LP_ILK, 0);
+       I915_WRITE(WM2_LP_ILK, 0);
+       I915_WRITE(WM1_LP_ILK, 0);
+
+       if (enabled != 1)
+               return;
+
+       clock = planea_clock ? planea_clock : planeb_clock;
+
+       /* WM1 */
+       if (!ironlake_compute_srwm(dev, 1, hdisplay, htotal, pixel_size,
+                                  clock, ILK_READ_WM1_LATENCY() * 500,
+                                  &ironlake_display_srwm_info,
+                                  &ironlake_cursor_srwm_info,
+                                  &fbc_wm, &plane_wm, &cursor_wm))
+               return;
+
+       I915_WRITE(WM1_LP_ILK,
+                  WM1_LP_SR_EN |
+                  (ILK_READ_WM1_LATENCY() << WM1_LP_LATENCY_SHIFT) |
+                  (fbc_wm << WM1_LP_FBC_SHIFT) |
+                  (plane_wm << WM1_LP_SR_SHIFT) |
+                  cursor_wm);
+
+       /* WM2 */
+       if (!ironlake_compute_srwm(dev, 2, hdisplay, htotal, pixel_size,
+                                  clock, ILK_READ_WM2_LATENCY() * 500,
+                                  &ironlake_display_srwm_info,
+                                  &ironlake_cursor_srwm_info,
+                                  &fbc_wm, &plane_wm, &cursor_wm))
+               return;
+
+       I915_WRITE(WM2_LP_ILK,
+                  WM2_LP_EN |
+                  (ILK_READ_WM2_LATENCY() << WM1_LP_LATENCY_SHIFT) |
+                  (fbc_wm << WM1_LP_FBC_SHIFT) |
+                  (plane_wm << WM1_LP_SR_SHIFT) |
+                  cursor_wm);
+
+       /*
+        * WM3 is unsupported on ILK, probably because we don't have latency
+        * data for that power state
+        */
 }
 
 static void sandybridge_update_wm(struct drm_device *dev,
@@ -3652,7 +3644,7 @@ static void sandybridge_update_wm(struct drm_device *dev,
                               int pixel_size)
 {
        struct drm_i915_private *dev_priv = dev->dev_private;
-       int latency = SNB_READ_WM0_LATENCY();
+       int latency = SNB_READ_WM0_LATENCY() * 100;     /* In unit 0.1us */
        int fbc_wm, plane_wm, cursor_wm, enabled;
        int clock;
 
@@ -3701,9 +3693,11 @@ static void sandybridge_update_wm(struct drm_device *dev,
        clock = planea_clock ? planea_clock : planeb_clock;
 
        /* WM1 */
-       if (!sandybridge_compute_srwm(dev, 1, hdisplay, htotal, pixel_size,
-                                     clock, SNB_READ_WM1_LATENCY() * 500,
-                                     &fbc_wm, &plane_wm, &cursor_wm))
+       if (!ironlake_compute_srwm(dev, 1, hdisplay, htotal, pixel_size,
+                                  clock, SNB_READ_WM1_LATENCY() * 500,
+                                  &sandybridge_display_srwm_info,
+                                  &sandybridge_cursor_srwm_info,
+                                  &fbc_wm, &plane_wm, &cursor_wm))
                return;
 
        I915_WRITE(WM1_LP_ILK,
@@ -3714,10 +3708,12 @@ static void sandybridge_update_wm(struct drm_device *dev,
                   cursor_wm);
 
        /* WM2 */
-       if (!sandybridge_compute_srwm(dev, 2,
-                                     hdisplay, htotal, pixel_size,
-                                     clock, SNB_READ_WM2_LATENCY() * 500,
-                                     &fbc_wm, &plane_wm, &cursor_wm))
+       if (!ironlake_compute_srwm(dev, 2,
+                                  hdisplay, htotal, pixel_size,
+                                  clock, SNB_READ_WM2_LATENCY() * 500,
+                                  &sandybridge_display_srwm_info,
+                                  &sandybridge_cursor_srwm_info,
+                                  &fbc_wm, &plane_wm, &cursor_wm))
                return;
 
        I915_WRITE(WM2_LP_ILK,
@@ -3728,10 +3724,12 @@ static void sandybridge_update_wm(struct drm_device *dev,
                   cursor_wm);
 
        /* WM3 */
-       if (!sandybridge_compute_srwm(dev, 3,
-                                     hdisplay, htotal, pixel_size,
-                                     clock, SNB_READ_WM3_LATENCY() * 500,
-                                     &fbc_wm, &plane_wm, &cursor_wm))
+       if (!ironlake_compute_srwm(dev, 3,
+                                  hdisplay, htotal, pixel_size,
+                                  clock, SNB_READ_WM3_LATENCY() * 500,
+                                  &sandybridge_display_srwm_info,
+                                  &sandybridge_cursor_srwm_info,
+                                  &fbc_wm, &plane_wm, &cursor_wm))
                return;
 
        I915_WRITE(WM3_LP_ILK,
@@ -5038,8 +5036,8 @@ static void intel_increase_pllclock(struct drm_crtc *crtc)
        drm_i915_private_t *dev_priv = dev->dev_private;
        struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
        int pipe = intel_crtc->pipe;
-       int dpll_reg = (pipe == 0) ? DPLL_A : DPLL_B;
-       int dpll = I915_READ(dpll_reg);
+       int dpll_reg = DPLL(pipe);
+       int dpll;
 
        if (HAS_PCH_SPLIT(dev))
                return;
@@ -5047,17 +5045,19 @@ static void intel_increase_pllclock(struct drm_crtc *crtc)
        if (!dev_priv->lvds_downclock_avail)
                return;
 
+       dpll = I915_READ(dpll_reg);
        if (!HAS_PIPE_CXSR(dev) && (dpll & DISPLAY_RATE_SELECT_FPA1)) {
                DRM_DEBUG_DRIVER("upclocking LVDS\n");
 
                /* Unlock panel regs */
-               I915_WRITE(PP_CONTROL, I915_READ(PP_CONTROL) |
-                          PANEL_UNLOCK_REGS);
+               I915_WRITE(PP_CONTROL,
+                          I915_READ(PP_CONTROL) | PANEL_UNLOCK_REGS);
 
                dpll &= ~DISPLAY_RATE_SELECT_FPA1;
                I915_WRITE(dpll_reg, dpll);
-               dpll = I915_READ(dpll_reg);
+               POSTING_READ(dpll_reg);
                intel_wait_for_vblank(dev, pipe);
+
                dpll = I915_READ(dpll_reg);
                if (dpll & DISPLAY_RATE_SELECT_FPA1)
                        DRM_DEBUG_DRIVER("failed to upclock LVDS!\n");
@@ -6415,42 +6415,6 @@ void intel_enable_clock_gating(struct drm_device *dev)
        } else if (IS_I830(dev)) {
                I915_WRITE(DSPCLK_GATE_D, OVRUNIT_CLOCK_GATE_DISABLE);
        }
-
-       /*
-        * GPU can automatically power down the render unit if given a page
-        * to save state.
-        */
-       if (IS_IRONLAKE_M(dev) && 0) { /* XXX causes a failure during suspend */
-               if (dev_priv->renderctx == NULL)
-                       dev_priv->renderctx = intel_alloc_context_page(dev);
-               if (dev_priv->renderctx) {
-                       struct drm_i915_gem_object *obj = dev_priv->renderctx;
-                       if (BEGIN_LP_RING(4) == 0) {
-                               OUT_RING(MI_SET_CONTEXT);
-                               OUT_RING(obj->gtt_offset |
-                                        MI_MM_SPACE_GTT |
-                                        MI_SAVE_EXT_STATE_EN |
-                                        MI_RESTORE_EXT_STATE_EN |
-                                        MI_RESTORE_INHIBIT);
-                               OUT_RING(MI_NOOP);
-                               OUT_RING(MI_FLUSH);
-                               ADVANCE_LP_RING();
-                       }
-               } else
-                       DRM_DEBUG_KMS("Failed to allocate render context."
-                                      "Disable RC6\n");
-       }
-
-       if (IS_GEN4(dev) && IS_MOBILE(dev)) {
-               if (dev_priv->pwrctx == NULL)
-                       dev_priv->pwrctx = intel_alloc_context_page(dev);
-               if (dev_priv->pwrctx) {
-                       struct drm_i915_gem_object *obj = dev_priv->pwrctx;
-                       I915_WRITE(PWRCTXA, obj->gtt_offset | PWRCTX_EN);
-                       I915_WRITE(MCHBAR_RENDER_STANDBY,
-                                  I915_READ(MCHBAR_RENDER_STANDBY) & ~RCX_SW_EXIT);
-               }
-       }
 }
 
 void intel_disable_clock_gating(struct drm_device *dev)
@@ -6480,6 +6444,57 @@ void intel_disable_clock_gating(struct drm_device *dev)
        }
 }
 
+static void ironlake_disable_rc6(struct drm_device *dev)
+{
+       struct drm_i915_private *dev_priv = dev->dev_private;
+
+       /* Wake the GPU, prevent RC6, then restore RSTDBYCTL */
+       I915_WRITE(RSTDBYCTL, I915_READ(RSTDBYCTL) | RCX_SW_EXIT);
+       wait_for(((I915_READ(RSTDBYCTL) & RSX_STATUS_MASK) == RSX_STATUS_ON),
+                10);
+       POSTING_READ(CCID);
+       I915_WRITE(PWRCTXA, 0);
+       POSTING_READ(PWRCTXA);
+       I915_WRITE(RSTDBYCTL, I915_READ(RSTDBYCTL) & ~RCX_SW_EXIT);
+       POSTING_READ(RSTDBYCTL);
+       i915_gem_object_unpin(dev_priv->renderctx);
+       drm_gem_object_unreference(&dev_priv->renderctx->base);
+       dev_priv->renderctx = NULL;
+       i915_gem_object_unpin(dev_priv->pwrctx);
+       drm_gem_object_unreference(&dev_priv->pwrctx->base);
+       dev_priv->pwrctx = NULL;
+}
+
+void ironlake_enable_rc6(struct drm_device *dev)
+{
+       struct drm_i915_private *dev_priv = dev->dev_private;
+       int ret;
+
+       /*
+        * GPU can automatically power down the render unit if given a page
+        * to save state.
+        */
+       ret = BEGIN_LP_RING(6);
+       if (ret) {
+               ironlake_disable_rc6(dev);
+               return;
+       }
+       OUT_RING(MI_SUSPEND_FLUSH | MI_SUSPEND_FLUSH_EN);
+       OUT_RING(MI_SET_CONTEXT);
+       OUT_RING(dev_priv->renderctx->gtt_offset |
+                MI_MM_SPACE_GTT |
+                MI_SAVE_EXT_STATE_EN |
+                MI_RESTORE_EXT_STATE_EN |
+                MI_RESTORE_INHIBIT);
+       OUT_RING(MI_SUSPEND_FLUSH);
+       OUT_RING(MI_NOOP);
+       OUT_RING(MI_FLUSH);
+       ADVANCE_LP_RING();
+
+       I915_WRITE(PWRCTXA, dev_priv->pwrctx->gtt_offset | PWRCTX_EN);
+       I915_WRITE(RSTDBYCTL, I915_READ(RSTDBYCTL) & ~RCX_SW_EXIT);
+}
+
 /* Set up chip specific display functions */
 static void intel_init_display(struct drm_device *dev)
 {
@@ -6722,6 +6737,21 @@ void intel_modeset_init(struct drm_device *dev)
        if (IS_GEN6(dev))
                gen6_enable_rps(dev_priv);
 
+       if (IS_IRONLAKE_M(dev)) {
+               dev_priv->renderctx = intel_alloc_context_page(dev);
+               if (!dev_priv->renderctx)
+                       goto skip_rc6;
+               dev_priv->pwrctx = intel_alloc_context_page(dev);
+               if (!dev_priv->pwrctx) {
+                       i915_gem_object_unpin(dev_priv->renderctx);
+                       drm_gem_object_unreference(&dev_priv->renderctx->base);
+                       dev_priv->renderctx = NULL;
+                       goto skip_rc6;
+               }
+               ironlake_enable_rc6(dev);
+       }
+
+skip_rc6:
        INIT_WORK(&dev_priv->idle_work, intel_idle_update);
        setup_timer(&dev_priv->idle_timer, intel_gpu_idle_timer,
                    (unsigned long)dev);
@@ -6758,7 +6788,8 @@ void intel_modeset_cleanup(struct drm_device *dev)
        if (IS_GEN6(dev))
                gen6_disable_rps(dev);
 
-       intel_disable_clock_gating(dev);
+       if (IS_IRONLAKE_M(dev))
+               ironlake_disable_rc6(dev);
 
        mutex_unlock(&dev->struct_mutex);