/* PCI config space */
 
 #define HPLLCC 0xc0 /* 855 only */
-#define   GC_CLOCK_CONTROL_MASK                (3 << 0)
+#define   GC_CLOCK_CONTROL_MASK                (0xf << 0)
 #define   GC_CLOCK_133_200             (0 << 0)
 #define   GC_CLOCK_100_200             (1 << 0)
 #define   GC_CLOCK_100_133             (2 << 0)
 #define   GC_DISPLAY_CLOCK_190_200_MHZ (0 << 4)
 #define   GC_DISPLAY_CLOCK_333_MHZ     (4 << 4)
 #define   GC_DISPLAY_CLOCK_MASK                (7 << 4)
+#define   GM45_GC_RENDER_CLOCK_MASK    (0xf << 0)
+#define   GM45_GC_RENDER_CLOCK_266_MHZ (8 << 0)
+#define   GM45_GC_RENDER_CLOCK_320_MHZ (9 << 0)
+#define   GM45_GC_RENDER_CLOCK_400_MHZ (0xb << 0)
+#define   GM45_GC_RENDER_CLOCK_533_MHZ (0xc << 0)
+#define   I965_GC_RENDER_CLOCK_MASK    (0xf << 0)
+#define   I965_GC_RENDER_CLOCK_267_MHZ (2 << 0)
+#define   I965_GC_RENDER_CLOCK_333_MHZ (3 << 0)
+#define   I965_GC_RENDER_CLOCK_444_MHZ (4 << 0)
+#define   I965_GC_RENDER_CLOCK_533_MHZ (5 << 0)
+#define   I945_GC_RENDER_CLOCK_MASK    (7 << 0)
+#define   I945_GC_RENDER_CLOCK_166_MHZ (0 << 0)
+#define   I945_GC_RENDER_CLOCK_200_MHZ (1 << 0)
+#define   I945_GC_RENDER_CLOCK_250_MHZ (3 << 0)
+#define   I945_GC_RENDER_CLOCK_400_MHZ (5 << 0)
+#define   I915_GC_RENDER_CLOCK_MASK    (7 << 0)
+#define   I915_GC_RENDER_CLOCK_166_MHZ (0 << 0)
+#define   I915_GC_RENDER_CLOCK_200_MHZ (1 << 0)
+#define   I915_GC_RENDER_CLOCK_333_MHZ (4 << 0)
 #define LBB    0xf4
 
 /* VGA stuff */
 #define   DPLLA_TEST_M_BYPASS          (1 << 2)
 #define   DPLLA_INPUT_BUFFER_ENABLE    (1 << 0)
 #define D_STATE                0x6104
-#define CG_2D_DIS      0x6200
-#define DPCUNIT_CLOCK_GATE_DISABLE     (1 << 24)
-#define CG_3D_DIS      0x6204
+#define  DSTATE_PLL_D3_OFF                     (1<<3)
+#define  DSTATE_GFX_CLOCK_GATING               (1<<1)
+#define  DSTATE_DOT_CLOCK_GATING               (1<<0)
+#define DSPCLK_GATE_D          0x6200
+# define DPUNIT_B_CLOCK_GATE_DISABLE           (1 << 30) /* 965 */
+# define VSUNIT_CLOCK_GATE_DISABLE             (1 << 29) /* 965 */
+# define VRHUNIT_CLOCK_GATE_DISABLE            (1 << 28) /* 965 */
+# define VRDUNIT_CLOCK_GATE_DISABLE            (1 << 27) /* 965 */
+# define AUDUNIT_CLOCK_GATE_DISABLE            (1 << 26) /* 965 */
+# define DPUNIT_A_CLOCK_GATE_DISABLE           (1 << 25) /* 965 */
+# define DPCUNIT_CLOCK_GATE_DISABLE            (1 << 24) /* 965 */
+# define TVRUNIT_CLOCK_GATE_DISABLE            (1 << 23) /* 915-945 */
+# define TVCUNIT_CLOCK_GATE_DISABLE            (1 << 22) /* 915-945 */
+# define TVFUNIT_CLOCK_GATE_DISABLE            (1 << 21) /* 915-945 */
+# define TVEUNIT_CLOCK_GATE_DISABLE            (1 << 20) /* 915-945 */
+# define DVSUNIT_CLOCK_GATE_DISABLE            (1 << 19) /* 915-945 */
+# define DSSUNIT_CLOCK_GATE_DISABLE            (1 << 18) /* 915-945 */
+# define DDBUNIT_CLOCK_GATE_DISABLE            (1 << 17) /* 915-945 */
+# define DPRUNIT_CLOCK_GATE_DISABLE            (1 << 16) /* 915-945 */
+# define DPFUNIT_CLOCK_GATE_DISABLE            (1 << 15) /* 915-945 */
+# define DPBMUNIT_CLOCK_GATE_DISABLE           (1 << 14) /* 915-945 */
+# define DPLSUNIT_CLOCK_GATE_DISABLE           (1 << 13) /* 915-945 */
+# define DPLUNIT_CLOCK_GATE_DISABLE            (1 << 12) /* 915-945 */
+# define DPOUNIT_CLOCK_GATE_DISABLE            (1 << 11)
+# define DPBUNIT_CLOCK_GATE_DISABLE            (1 << 10)
+# define DCUNIT_CLOCK_GATE_DISABLE             (1 << 9)
+# define DPUNIT_CLOCK_GATE_DISABLE             (1 << 8)
+# define VRUNIT_CLOCK_GATE_DISABLE             (1 << 7) /* 915+: reserved */
+# define OVHUNIT_CLOCK_GATE_DISABLE            (1 << 6) /* 830-865 */
+# define DPIOUNIT_CLOCK_GATE_DISABLE           (1 << 6) /* 915-945 */
+# define OVFUNIT_CLOCK_GATE_DISABLE            (1 << 5)
+# define OVBUNIT_CLOCK_GATE_DISABLE            (1 << 4)
+/**
+ * This bit must be set on the 830 to prevent hangs when turning off the
+ * overlay scaler.
+ */
+# define OVRUNIT_CLOCK_GATE_DISABLE            (1 << 3)
+# define OVCUNIT_CLOCK_GATE_DISABLE            (1 << 2)
+# define OVUUNIT_CLOCK_GATE_DISABLE            (1 << 1)
+# define ZVUNIT_CLOCK_GATE_DISABLE             (1 << 0) /* 830 */
+# define OVLUNIT_CLOCK_GATE_DISABLE            (1 << 0) /* 845,865 */
+
+#define RENCLK_GATE_D1         0x6204
+# define BLITTER_CLOCK_GATE_DISABLE            (1 << 13) /* 945GM only */
+# define MPEG_CLOCK_GATE_DISABLE               (1 << 12) /* 945GM only */
+# define PC_FE_CLOCK_GATE_DISABLE              (1 << 11)
+# define PC_BE_CLOCK_GATE_DISABLE              (1 << 10)
+# define WINDOWER_CLOCK_GATE_DISABLE           (1 << 9)
+# define INTERPOLATOR_CLOCK_GATE_DISABLE       (1 << 8)
+# define COLOR_CALCULATOR_CLOCK_GATE_DISABLE   (1 << 7)
+# define MOTION_COMP_CLOCK_GATE_DISABLE                (1 << 6)
+# define MAG_CLOCK_GATE_DISABLE                        (1 << 5)
+/** This bit must be unset on 855,865 */
+# define MECI_CLOCK_GATE_DISABLE               (1 << 4)
+# define DCMP_CLOCK_GATE_DISABLE               (1 << 3)
+# define MEC_CLOCK_GATE_DISABLE                        (1 << 2)
+# define MECO_CLOCK_GATE_DISABLE               (1 << 1)
+/** This bit must be set on 855,865. */
+# define SV_CLOCK_GATE_DISABLE                 (1 << 0)
+# define I915_MPEG_CLOCK_GATE_DISABLE          (1 << 16)
+# define I915_VLD_IP_PR_CLOCK_GATE_DISABLE     (1 << 15)
+# define I915_MOTION_COMP_CLOCK_GATE_DISABLE   (1 << 14)
+# define I915_BD_BF_CLOCK_GATE_DISABLE         (1 << 13)
+# define I915_SF_SE_CLOCK_GATE_DISABLE         (1 << 12)
+# define I915_WM_CLOCK_GATE_DISABLE            (1 << 11)
+# define I915_IZ_CLOCK_GATE_DISABLE            (1 << 10)
+# define I915_PI_CLOCK_GATE_DISABLE            (1 << 9)
+# define I915_DI_CLOCK_GATE_DISABLE            (1 << 8)
+# define I915_SH_SV_CLOCK_GATE_DISABLE         (1 << 7)
+# define I915_PL_DG_QC_FT_CLOCK_GATE_DISABLE   (1 << 6)
+# define I915_SC_CLOCK_GATE_DISABLE            (1 << 5)
+# define I915_FL_CLOCK_GATE_DISABLE            (1 << 4)
+# define I915_DM_CLOCK_GATE_DISABLE            (1 << 3)
+# define I915_PS_CLOCK_GATE_DISABLE            (1 << 2)
+# define I915_CC_CLOCK_GATE_DISABLE            (1 << 1)
+# define I915_BY_CLOCK_GATE_DISABLE            (1 << 0)
+
+# define I965_RCZ_CLOCK_GATE_DISABLE           (1 << 30)
+/** This bit must always be set on 965G/965GM */
+# define I965_RCC_CLOCK_GATE_DISABLE           (1 << 29)
+# define I965_RCPB_CLOCK_GATE_DISABLE          (1 << 28)
+# define I965_DAP_CLOCK_GATE_DISABLE           (1 << 27)
+# define I965_ROC_CLOCK_GATE_DISABLE           (1 << 26)
+# define I965_GW_CLOCK_GATE_DISABLE            (1 << 25)
+# define I965_TD_CLOCK_GATE_DISABLE            (1 << 24)
+/** This bit must always be set on 965G */
+# define I965_ISC_CLOCK_GATE_DISABLE           (1 << 23)
+# define I965_IC_CLOCK_GATE_DISABLE            (1 << 22)
+# define I965_EU_CLOCK_GATE_DISABLE            (1 << 21)
+# define I965_IF_CLOCK_GATE_DISABLE            (1 << 20)
+# define I965_TC_CLOCK_GATE_DISABLE            (1 << 19)
+# define I965_SO_CLOCK_GATE_DISABLE            (1 << 17)
+# define I965_FBC_CLOCK_GATE_DISABLE           (1 << 16)
+# define I965_MARI_CLOCK_GATE_DISABLE          (1 << 15)
+# define I965_MASF_CLOCK_GATE_DISABLE          (1 << 14)
+# define I965_MAWB_CLOCK_GATE_DISABLE          (1 << 13)
+# define I965_EM_CLOCK_GATE_DISABLE            (1 << 12)
+# define I965_UC_CLOCK_GATE_DISABLE            (1 << 11)
+# define I965_SI_CLOCK_GATE_DISABLE            (1 << 6)
+# define I965_MT_CLOCK_GATE_DISABLE            (1 << 5)
+# define I965_PL_CLOCK_GATE_DISABLE            (1 << 4)
+# define I965_DG_CLOCK_GATE_DISABLE            (1 << 3)
+# define I965_QC_CLOCK_GATE_DISABLE            (1 << 2)
+# define I965_FT_CLOCK_GATE_DISABLE            (1 << 1)
+# define I965_DM_CLOCK_GATE_DISABLE            (1 << 0)
+
+#define RENCLK_GATE_D2         0x6208
+#define VF_UNIT_CLOCK_GATE_DISABLE             (1 << 9)
+#define GS_UNIT_CLOCK_GATE_DISABLE             (1 << 7)
+#define CL_UNIT_CLOCK_GATE_DISABLE             (1 << 6)
+#define RAMCLK_GATE_D          0x6210          /* CRL only */
+#define DEUC                   0x6214          /* CRL only */
 
 /*
  * Palette regs
 #define   PIPECONF_PROGRESSIVE (0 << 21)
 #define   PIPECONF_INTERLACE_W_FIELD_INDICATION        (6 << 21)
 #define   PIPECONF_INTERLACE_FIELD_0_ONLY              (7 << 21)
+#define   PIPECONF_CXSR_DOWNCLOCK      (1<<16)
 #define PIPEASTAT              0x70024
 #define   PIPE_FIFO_UNDERRUN_STATUS            (1UL<<31)
 #define   PIPE_CRC_ERROR_ENABLE                        (1UL<<29)
 
 
 bool intel_pipe_has_type (struct drm_crtc *crtc, int type);
 static void intel_update_watermarks(struct drm_device *dev);
+static void intel_increase_pllclock(struct drm_crtc *crtc, bool schedule);
 
 typedef struct {
     /* given values */
     intel_p2_t     p2;
     bool (* find_pll)(const intel_limit_t *, struct drm_crtc *,
                      int, int, intel_clock_t *);
+    bool (* find_reduced_pll)(const intel_limit_t *, struct drm_crtc *,
+                             int, int, intel_clock_t *);
 };
 
 #define I8XX_DOT_MIN             25000
 intel_find_best_PLL(const intel_limit_t *limit, struct drm_crtc *crtc,
                    int target, int refclk, intel_clock_t *best_clock);
 static bool
+intel_find_best_reduced_PLL(const intel_limit_t *limit, struct drm_crtc *crtc,
+                           int target, int refclk, intel_clock_t *best_clock);
+static bool
 intel_g4x_find_best_PLL(const intel_limit_t *limit, struct drm_crtc *crtc,
                        int target, int refclk, intel_clock_t *best_clock);
 static bool
        .p2  = { .dot_limit = I8XX_P2_SLOW_LIMIT,
                 .p2_slow = I8XX_P2_SLOW,       .p2_fast = I8XX_P2_FAST },
        .find_pll = intel_find_best_PLL,
+       .find_reduced_pll = intel_find_best_reduced_PLL,
 };
 
 static const intel_limit_t intel_limits_i8xx_lvds = {
        .p2  = { .dot_limit = I8XX_P2_SLOW_LIMIT,
                 .p2_slow = I8XX_P2_LVDS_SLOW,  .p2_fast = I8XX_P2_LVDS_FAST },
        .find_pll = intel_find_best_PLL,
+       .find_reduced_pll = intel_find_best_reduced_PLL,
 };
        
 static const intel_limit_t intel_limits_i9xx_sdvo = {
        .p2  = { .dot_limit = I9XX_P2_SDVO_DAC_SLOW_LIMIT,
                 .p2_slow = I9XX_P2_SDVO_DAC_SLOW,      .p2_fast = I9XX_P2_SDVO_DAC_FAST },
        .find_pll = intel_find_best_PLL,
+       .find_reduced_pll = intel_find_best_reduced_PLL,
 };
 
 static const intel_limit_t intel_limits_i9xx_lvds = {
        .p2  = { .dot_limit = I9XX_P2_LVDS_SLOW_LIMIT,
                 .p2_slow = I9XX_P2_LVDS_SLOW,  .p2_fast = I9XX_P2_LVDS_FAST },
        .find_pll = intel_find_best_PLL,
+       .find_reduced_pll = intel_find_best_reduced_PLL,
 };
 
     /* below parameter and function is for G4X Chipset Family*/
                 .p2_fast = G4X_P2_SDVO_FAST
        },
        .find_pll = intel_g4x_find_best_PLL,
+       .find_reduced_pll = intel_g4x_find_best_PLL,
 };
 
 static const intel_limit_t intel_limits_g4x_hdmi = {
                 .p2_fast = G4X_P2_HDMI_DAC_FAST
        },
        .find_pll = intel_g4x_find_best_PLL,
+       .find_reduced_pll = intel_g4x_find_best_PLL,
 };
 
 static const intel_limit_t intel_limits_g4x_single_channel_lvds = {
                 .p2_fast = G4X_P2_SINGLE_CHANNEL_LVDS_FAST
        },
        .find_pll = intel_g4x_find_best_PLL,
+       .find_reduced_pll = intel_g4x_find_best_PLL,
 };
 
 static const intel_limit_t intel_limits_g4x_dual_channel_lvds = {
                 .p2_fast = G4X_P2_DUAL_CHANNEL_LVDS_FAST
        },
        .find_pll = intel_g4x_find_best_PLL,
+       .find_reduced_pll = intel_g4x_find_best_PLL,
 };
 
 static const intel_limit_t intel_limits_g4x_display_port = {
        .p2  = { .dot_limit = I9XX_P2_SDVO_DAC_SLOW_LIMIT,
                 .p2_slow = I9XX_P2_SDVO_DAC_SLOW,      .p2_fast = I9XX_P2_SDVO_DAC_FAST },
        .find_pll = intel_find_best_PLL,
+       .find_reduced_pll = intel_find_best_reduced_PLL,
 };
 
 static const intel_limit_t intel_limits_igd_lvds = {
        .p2  = { .dot_limit = I9XX_P2_LVDS_SLOW_LIMIT,
                 .p2_slow = I9XX_P2_LVDS_SLOW,  .p2_fast = I9XX_P2_LVDS_SLOW },
        .find_pll = intel_find_best_PLL,
+       .find_reduced_pll = intel_find_best_reduced_PLL,
 };
 
 static const intel_limit_t intel_limits_igdng_sdvo = {
 
        memset (best_clock, 0, sizeof (*best_clock));
 
-       for (clock.m1 = limit->m1.min; clock.m1 <= limit->m1.max; clock.m1++) {
-               for (clock.m2 = limit->m2.min; clock.m2 <= limit->m2.max; clock.m2++) {
-                       /* m1 is always 0 in IGD */
-                       if (clock.m2 >= clock.m1 && !IS_IGD(dev))
-                               break;
-                       for (clock.n = limit->n.min; clock.n <= limit->n.max;
-                            clock.n++) {
-                               for (clock.p1 = limit->p1.min;
-                                    clock.p1 <= limit->p1.max; clock.p1++) {
+       for (clock.p1 = limit->p1.max; clock.p1 >= limit->p1.min; clock.p1--) {
+               for (clock.m1 = limit->m1.min; clock.m1 <= limit->m1.max;
+                    clock.m1++) {
+                       for (clock.m2 = limit->m2.min;
+                            clock.m2 <= limit->m2.max; clock.m2++) {
+                               /* m1 is always 0 in IGD */
+                               if (clock.m2 >= clock.m1 && !IS_IGD(dev))
+                                       break;
+                               for (clock.n = limit->n.min;
+                                    clock.n <= limit->n.max; clock.n++) {
                                        int this_err;
 
                                        intel_clock(dev, refclk, &clock);
        return (err != target);
 }
 
+
+static bool
+intel_find_best_reduced_PLL(const intel_limit_t *limit, struct drm_crtc *crtc,
+                           int target, int refclk, intel_clock_t *best_clock)
+
+{
+       struct drm_device *dev = crtc->dev;
+       intel_clock_t clock;
+       int err = target;
+       bool found = false;
+
+       memcpy(&clock, best_clock, sizeof(intel_clock_t));
+
+       for (clock.m1 = limit->m1.min; clock.m1 <= limit->m1.max; clock.m1++) {
+               for (clock.m2 = limit->m2.min; clock.m2 <= limit->m2.max; clock.m2++) {
+                       /* m1 is always 0 in IGD */
+                       if (clock.m2 >= clock.m1 && !IS_IGD(dev))
+                               break;
+                       for (clock.n = limit->n.min; clock.n <= limit->n.max;
+                            clock.n++) {
+                               int this_err;
+
+                               intel_clock(dev, refclk, &clock);
+
+                               if (!intel_PLL_is_valid(crtc, &clock))
+                                       continue;
+
+                               this_err = abs(clock.dot - target);
+                               if (this_err < err) {
+                                       *best_clock = clock;
+                                       err = this_err;
+                                       found = true;
+                               }
+                       }
+               }
+       }
+
+       return found;
+}
+
 static bool
 intel_g4x_find_best_PLL(const intel_limit_t *limit, struct drm_crtc *crtc,
                        int target, int refclk, intel_clock_t *best_clock)
        max_n = limit->n.max;
        /* based on hardware requriment prefer smaller n to precision */
        for (clock.n = limit->n.min; clock.n <= max_n; clock.n++) {
-               /* based on hardware requirment prefere larger m1,m2, p1 */
+               /* based on hardware requirment prefere larger m1,m2 */
                for (clock.m1 = limit->m1.max;
                     clock.m1 >= limit->m1.min; clock.m1--) {
                        for (clock.m2 = limit->m2.max;
 
        memset(best_clock, 0, sizeof(*best_clock));
        max_n = limit->n.max;
-       /* based on hardware requriment prefer smaller n to precision */
-       for (clock.n = limit->n.min; clock.n <= max_n; clock.n++) {
-               /* based on hardware requirment prefere larger m1,m2, p1 */
-               for (clock.m1 = limit->m1.max;
-                    clock.m1 >= limit->m1.min; clock.m1--) {
-                       for (clock.m2 = limit->m2.max;
-                            clock.m2 >= limit->m2.min; clock.m2--) {
-                               for (clock.p1 = limit->p1.max;
-                                    clock.p1 >= limit->p1.min; clock.p1--) {
+       for (clock.p1 = limit->p1.max; clock.p1 >= limit->p1.min; clock.p1--) {
+               /* based on hardware requriment prefer smaller n to precision */
+               for (clock.n = limit->n.min; clock.n <= max_n; clock.n++) {
+                       /* based on hardware requirment prefere larger m1,m2 */
+                       for (clock.m1 = limit->m1.max;
+                            clock.m1 >= limit->m1.min; clock.m1--) {
+                               for (clock.m2 = limit->m2.max;
+                                    clock.m2 >= limit->m2.min; clock.m2--) {
                                        int this_err;
 
                                        intel_clock(dev, refclk, &clock);
 
        if (old_fb) {
                intel_fb = to_intel_framebuffer(old_fb);
+               obj_priv = intel_fb->obj->driver_private;
                i915_gem_object_unpin(intel_fb->obj);
        }
+       intel_increase_pllclock(crtc, true);
+
        mutex_unlock(&dev->struct_mutex);
 
        if (!dev->primary->master)
        return size;
 }
 
+static void g4x_update_wm(struct drm_device *dev)
+{
+       struct drm_i915_private *dev_priv = dev->dev_private;
+       u32 fw_blc_self = I915_READ(FW_BLC_SELF);
+
+       if (i915_powersave)
+               fw_blc_self |= FW_BLC_SELF_EN;
+       else
+               fw_blc_self &= ~FW_BLC_SELF_EN;
+       I915_WRITE(FW_BLC_SELF, fw_blc_self);
+}
+
 static void i965_update_wm(struct drm_device *dev)
 {
        struct drm_i915_private *dev_priv = dev->dev_private;
        cwm = 2;
 
        /* Calc sr entries for one plane configs */
-       if (sr_hdisplay && (!planea_clock || !planeb_clock)) {
+       if (HAS_FW_BLC(dev) && sr_hdisplay &&
+           (!planea_clock || !planeb_clock)) {
                /* self-refresh has much higher latency */
                const static int sr_latency_ns = 6000;
 
                srwm = total_size - sr_entries;
                if (srwm < 0)
                        srwm = 1;
-               if (IS_I9XX(dev))
-                       I915_WRITE(FW_BLC_SELF, (srwm & 0x3f));
+               I915_WRITE(FW_BLC_SELF, FW_BLC_SELF_EN | (srwm & 0x3f));
        }
 
        DRM_DEBUG("Setting FIFO watermarks - A: %d, B: %d, C: %d, SR %d\n",
        unsigned long planea_clock = 0, planeb_clock = 0, sr_clock = 0;
        int enabled = 0, pixel_size = 0;
 
-       if (DSPARB_HWCONTROL(dev))
-               return;
-
        /* Get the clock config from both planes */
        list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
                intel_crtc = to_intel_crtc(crtc);
        else if (IS_IGD(dev))
                igd_disable_cxsr(dev);
 
-       if (IS_I965G(dev))
+       if (IS_G4X(dev))
+               g4x_update_wm(dev);
+       else if (IS_I965G(dev))
                i965_update_wm(dev);
        else if (IS_I9XX(dev) || IS_MOBILE(dev))
                i9xx_update_wm(dev, planea_clock, planeb_clock, sr_hdisplay,
        int dsppos_reg = (pipe == 0) ? DSPAPOS : DSPBPOS;
        int pipesrc_reg = (pipe == 0) ? PIPEASRC : PIPEBSRC;
        int refclk, num_outputs = 0;
-       intel_clock_t clock;
-       u32 dpll = 0, fp = 0, dspcntr, pipeconf;
-       bool ok, is_sdvo = false, is_dvo = false;
+       intel_clock_t clock, reduced_clock;
+       u32 dpll = 0, fp = 0, fp2 = 0, dspcntr, pipeconf;
+       bool ok, has_reduced_clock = false, is_sdvo = false, is_dvo = false;
        bool is_crt = false, is_lvds = false, is_tv = false, is_dp = false;
        bool is_edp = false;
        struct drm_mode_config *mode_config = &dev->mode_config;
                return -EINVAL;
        }
 
+       if (limit->find_reduced_pll && dev_priv->lvds_downclock_avail) {
+               memcpy(&reduced_clock, &clock, sizeof(intel_clock_t));
+               has_reduced_clock = limit->find_reduced_pll(limit, crtc,
+                                                           (adjusted_mode->clock*3/4),
+                                                           refclk,
+                                                           &reduced_clock);
+       }
+
        /* SDVO TV has fixed PLL values depend on its clock range,
           this mirrors vbios setting. */
        if (is_sdvo && is_tv) {
                                  link_bw, &m_n);
        }
 
-       if (IS_IGD(dev))
+       if (IS_IGD(dev)) {
                fp = (1 << clock.n) << 16 | clock.m1 << 8 | clock.m2;
-       else
+               if (has_reduced_clock)
+                       fp2 = (1 << reduced_clock.n) << 16 |
+                               reduced_clock.m1 << 8 | reduced_clock.m2;
+       } else {
                fp = clock.n << 16 | clock.m1 << 8 | clock.m2;
+               if (has_reduced_clock)
+                       fp2 = reduced_clock.n << 16 | reduced_clock.m1 << 8 |
+                               reduced_clock.m2;
+       }
 
        if (!IS_IGDNG(dev))
                dpll = DPLL_VGA_MODE_DIS;
                        /* also FPA1 */
                        if (IS_IGDNG(dev))
                                dpll |= (1 << (clock.p1 - 1)) << DPLL_FPA1_P1_POST_DIV_SHIFT;
+                       if (IS_G4X(dev) && has_reduced_clock)
+                               dpll |= (1 << (reduced_clock.p1 - 1)) << DPLL_FPA1_P1_POST_DIV_SHIFT;
                }
                switch (clock.p2) {
                case 5:
                udelay(150);
        }
 
+       if (is_lvds && has_reduced_clock && i915_powersave) {
+               I915_WRITE(fp_reg + 4, fp2);
+               intel_crtc->lowfreq_avail = true;
+               if (HAS_PIPE_CXSR(dev)) {
+                       DRM_DEBUG("enabling CxSR downclocking\n");
+                       pipeconf |= PIPECONF_CXSR_DOWNCLOCK;
+               }
+       } else {
+               I915_WRITE(fp_reg + 4, fp);
+               intel_crtc->lowfreq_avail = false;
+               if (HAS_PIPE_CXSR(dev)) {
+                       DRM_DEBUG("disabling CxSR downclocking\n");
+                       pipeconf &= ~PIPECONF_CXSR_DOWNCLOCK;
+               }
+       }
+
        I915_WRITE(htot_reg, (adjusted_mode->crtc_hdisplay - 1) |
                   ((adjusted_mode->crtc_htotal - 1) << 16));
        I915_WRITE(hblank_reg, (adjusted_mode->crtc_hblank_start - 1) |
        struct drm_device *dev = crtc->dev;
        struct drm_i915_private *dev_priv = dev->dev_private;
        struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
+       struct intel_framebuffer *intel_fb;
        int pipe = intel_crtc->pipe;
        uint32_t temp = 0;
        uint32_t adder;
 
+       if (crtc->fb) {
+               intel_fb = to_intel_framebuffer(crtc->fb);
+               intel_mark_busy(dev, intel_fb->obj);
+       }
+
        if (x < 0) {
                temp |= CURSOR_POS_SIGN << CURSOR_X_SHIFT;
                x = -x;
        return mode;
 }
 
+#define GPU_IDLE_TIMEOUT 500 /* ms */
+
+/* When this timer fires, we've been idle for awhile */
+static void intel_gpu_idle_timer(unsigned long arg)
+{
+       struct drm_device *dev = (struct drm_device *)arg;
+       drm_i915_private_t *dev_priv = dev->dev_private;
+
+       DRM_DEBUG("idle timer fired, downclocking\n");
+
+       dev_priv->busy = false;
+
+       schedule_work(&dev_priv->idle_work);
+}
+
+void intel_increase_renderclock(struct drm_device *dev, bool schedule)
+{
+       drm_i915_private_t *dev_priv = dev->dev_private;
+
+       if (IS_IGDNG(dev))
+               return;
+
+       if (!dev_priv->render_reclock_avail) {
+               DRM_ERROR("not reclocking render clock\n");
+               return;
+       }
+
+       /* Restore render clock frequency to original value */
+       if (IS_G4X(dev) || IS_I9XX(dev))
+               pci_write_config_word(dev->pdev, GCFGC, dev_priv->orig_clock);
+       else if (IS_I85X(dev))
+               pci_write_config_word(dev->pdev, HPLLCC, dev_priv->orig_clock);
+       DRM_DEBUG("increasing render clock frequency\n");
+
+       /* Schedule downclock */
+       if (schedule)
+               mod_timer(&dev_priv->idle_timer, jiffies +
+                         msecs_to_jiffies(GPU_IDLE_TIMEOUT));
+}
+
+void intel_decrease_renderclock(struct drm_device *dev)
+{
+       drm_i915_private_t *dev_priv = dev->dev_private;
+
+       if (IS_IGDNG(dev))
+               return;
+
+       if (!dev_priv->render_reclock_avail) {
+               DRM_ERROR("not reclocking render clock\n");
+               return;
+       }
+
+       if (IS_G4X(dev)) {
+               u16 gcfgc;
+
+               /* Adjust render clock... */
+               pci_read_config_word(dev->pdev, GCFGC, &gcfgc);
+
+               /* Down to minimum... */
+               gcfgc &= ~GM45_GC_RENDER_CLOCK_MASK;
+               gcfgc |= GM45_GC_RENDER_CLOCK_266_MHZ;
+
+               pci_write_config_word(dev->pdev, GCFGC, gcfgc);
+       } else if (IS_I965G(dev)) {
+               u16 gcfgc;
+
+               /* Adjust render clock... */
+               pci_read_config_word(dev->pdev, GCFGC, &gcfgc);
+
+               /* Down to minimum... */
+               gcfgc &= ~I965_GC_RENDER_CLOCK_MASK;
+               gcfgc |= I965_GC_RENDER_CLOCK_267_MHZ;
+
+               pci_write_config_word(dev->pdev, GCFGC, gcfgc);
+       } else if (IS_I945G(dev) || IS_I945GM(dev)) {
+               u16 gcfgc;
+
+               /* Adjust render clock... */
+               pci_read_config_word(dev->pdev, GCFGC, &gcfgc);
+
+               /* Down to minimum... */
+               gcfgc &= ~I945_GC_RENDER_CLOCK_MASK;
+               gcfgc |= I945_GC_RENDER_CLOCK_166_MHZ;
+
+               pci_write_config_word(dev->pdev, GCFGC, gcfgc);
+       } else if (IS_I915G(dev)) {
+               u16 gcfgc;
+
+               /* Adjust render clock... */
+               pci_read_config_word(dev->pdev, GCFGC, &gcfgc);
+
+               /* Down to minimum... */
+               gcfgc &= ~I915_GC_RENDER_CLOCK_MASK;
+               gcfgc |= I915_GC_RENDER_CLOCK_166_MHZ;
+
+               pci_write_config_word(dev->pdev, GCFGC, gcfgc);
+       } else if (IS_I85X(dev)) {
+               u16 hpllcc;
+
+               /* Adjust render clock... */
+               pci_read_config_word(dev->pdev, HPLLCC, &hpllcc);
+
+               /* Up to maximum... */
+               hpllcc &= ~GC_CLOCK_CONTROL_MASK;
+               hpllcc |= GC_CLOCK_133_200;
+
+               pci_write_config_word(dev->pdev, HPLLCC, hpllcc);
+       }
+       DRM_DEBUG("decreasing render clock frequency\n");
+}
+
+/* Note that no increase function is needed for this - increase_renderclock()
+ *  will also rewrite these bits
+ */
+void intel_decrease_displayclock(struct drm_device *dev)
+{
+       if (IS_IGDNG(dev))
+               return;
+
+       if (IS_I945G(dev) || IS_I945GM(dev) || IS_I915G(dev) ||
+           IS_I915GM(dev)) {
+               u16 gcfgc;
+
+               /* Adjust render clock... */
+               pci_read_config_word(dev->pdev, GCFGC, &gcfgc);
+
+               /* Down to minimum... */
+               gcfgc &= ~0xf0;
+               gcfgc |= 0x80;
+
+               pci_write_config_word(dev->pdev, GCFGC, gcfgc);
+       }
+}
+
+#define CRTC_IDLE_TIMEOUT 1000 /* ms */
+
+static void intel_crtc_idle_timer(unsigned long arg)
+{
+       struct intel_crtc *intel_crtc = (struct intel_crtc *)arg;
+       struct drm_crtc *crtc = &intel_crtc->base;
+       drm_i915_private_t *dev_priv = crtc->dev->dev_private;
+
+       DRM_DEBUG("idle timer fired, downclocking\n");
+
+       intel_crtc->busy = false;
+
+       schedule_work(&dev_priv->idle_work);
+}
+
+static void intel_increase_pllclock(struct drm_crtc *crtc, bool schedule)
+{
+       struct drm_device *dev = crtc->dev;
+       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);
+
+       if (IS_IGDNG(dev))
+               return;
+
+       if (!dev_priv->lvds_downclock_avail)
+               return;
+
+       if (!HAS_PIPE_CXSR(dev) && (dpll & DISPLAY_RATE_SELECT_FPA1)) {
+               DRM_DEBUG("upclocking LVDS\n");
+
+               /* Unlock panel regs */
+               I915_WRITE(PP_CONTROL, I915_READ(PP_CONTROL) | (0xabcd << 16));
+
+               dpll &= ~DISPLAY_RATE_SELECT_FPA1;
+               I915_WRITE(dpll_reg, dpll);
+               dpll = I915_READ(dpll_reg);
+               intel_wait_for_vblank(dev);
+               dpll = I915_READ(dpll_reg);
+               if (dpll & DISPLAY_RATE_SELECT_FPA1)
+                       DRM_DEBUG("failed to upclock LVDS!\n");
+
+               /* ...and lock them again */
+               I915_WRITE(PP_CONTROL, I915_READ(PP_CONTROL) & 0x3);
+       }
+
+       /* Schedule downclock */
+       if (schedule)
+               mod_timer(&intel_crtc->idle_timer, jiffies +
+                         msecs_to_jiffies(CRTC_IDLE_TIMEOUT));
+}
+
+static void intel_decrease_pllclock(struct drm_crtc *crtc)
+{
+       struct drm_device *dev = crtc->dev;
+       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);
+
+       if (IS_IGDNG(dev))
+               return;
+
+       if (!dev_priv->lvds_downclock_avail)
+               return;
+
+       /*
+        * Since this is called by a timer, we should never get here in
+        * the manual case.
+        */
+       if (!HAS_PIPE_CXSR(dev) && intel_crtc->lowfreq_avail) {
+               DRM_DEBUG("downclocking LVDS\n");
+
+               /* Unlock panel regs */
+               I915_WRITE(PP_CONTROL, I915_READ(PP_CONTROL) | (0xabcd << 16));
+
+               dpll |= DISPLAY_RATE_SELECT_FPA1;
+               I915_WRITE(dpll_reg, dpll);
+               dpll = I915_READ(dpll_reg);
+               intel_wait_for_vblank(dev);
+               dpll = I915_READ(dpll_reg);
+               if (!(dpll & DISPLAY_RATE_SELECT_FPA1))
+                       DRM_DEBUG("failed to downclock LVDS!\n");
+
+               /* ...and lock them again */
+               I915_WRITE(PP_CONTROL, I915_READ(PP_CONTROL) & 0x3);
+       }
+
+}
+
+/**
+ * intel_idle_update - adjust clocks for idleness
+ * @work: work struct
+ *
+ * Either the GPU or display (or both) went idle.  Check the busy status
+ * here and adjust the CRTC and GPU clocks as necessary.
+ */
+static void intel_idle_update(struct work_struct *work)
+{
+       drm_i915_private_t *dev_priv = container_of(work, drm_i915_private_t,
+                                                   idle_work);
+       struct drm_device *dev = dev_priv->dev;
+       struct drm_crtc *crtc;
+       struct intel_crtc *intel_crtc;
+
+       if (!i915_powersave)
+               return;
+
+       mutex_lock(&dev->struct_mutex);
+
+       /* GPU isn't processing, downclock it. */
+       if (!dev_priv->busy) {
+               intel_decrease_renderclock(dev);
+               intel_decrease_displayclock(dev);
+       }
+
+       list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
+               /* Skip inactive CRTCs */
+               if (!crtc->fb)
+                       continue;
+
+               intel_crtc = to_intel_crtc(crtc);
+               if (!intel_crtc->busy)
+                       intel_decrease_pllclock(crtc);
+       }
+
+       mutex_unlock(&dev->struct_mutex);
+}
+
+/**
+ * intel_mark_busy - mark the GPU and possibly the display busy
+ * @dev: drm device
+ * @obj: object we're operating on
+ *
+ * Callers can use this function to indicate that the GPU is busy processing
+ * commands.  If @obj matches one of the CRTC objects (i.e. it's a scanout
+ * buffer), we'll also mark the display as busy, so we know to increase its
+ * clock frequency.
+ */
+void intel_mark_busy(struct drm_device *dev, struct drm_gem_object *obj)
+{
+       drm_i915_private_t *dev_priv = dev->dev_private;
+       struct drm_crtc *crtc = NULL;
+       struct intel_framebuffer *intel_fb;
+       struct intel_crtc *intel_crtc;
+
+       dev_priv->busy = true;
+       intel_increase_renderclock(dev, true);
+
+       list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
+               if (!crtc->fb)
+                       continue;
+
+               intel_crtc = to_intel_crtc(crtc);
+               intel_fb = to_intel_framebuffer(crtc->fb);
+               if (intel_fb->obj == obj) {
+                       if (!intel_crtc->busy) {
+                               /* Non-busy -> busy, upclock */
+                               intel_increase_pllclock(crtc, true);
+                               intel_crtc->busy = true;
+                       } else {
+                               /* Busy -> busy, put off timer */
+                               mod_timer(&intel_crtc->idle_timer, jiffies +
+                                         msecs_to_jiffies(CRTC_IDLE_TIMEOUT));
+                       }
+               }
+       }
+}
+
 static void intel_crtc_destroy(struct drm_crtc *crtc)
 {
        struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
        intel_crtc->mode_set.crtc = &intel_crtc->base;
        intel_crtc->mode_set.connectors = (struct drm_connector **)(intel_crtc + 1);
        intel_crtc->mode_set.num_connectors = 0;
+       intel_crtc->busy = false;
+
+       setup_timer(&intel_crtc->idle_timer, intel_crtc_idle_timer,
+                   (unsigned long)intel_crtc);
 
        if (i915_fbpercrtc) {
 
        .fb_changed = intelfb_probe,
 };
 
+void intel_init_clock_gating(struct drm_device *dev)
+{
+       struct drm_i915_private *dev_priv = dev->dev_private;
+
+       /*
+        * Disable clock gating reported to work incorrectly according to the
+        * specs, but enable as much else as we can.
+        */
+       if (IS_G4X(dev)) {
+               uint32_t dspclk_gate;
+               I915_WRITE(RENCLK_GATE_D1, 0);
+               I915_WRITE(RENCLK_GATE_D2, VF_UNIT_CLOCK_GATE_DISABLE |
+                      GS_UNIT_CLOCK_GATE_DISABLE |
+                      CL_UNIT_CLOCK_GATE_DISABLE);
+               I915_WRITE(RAMCLK_GATE_D, 0);
+               dspclk_gate = VRHUNIT_CLOCK_GATE_DISABLE |
+                       OVRUNIT_CLOCK_GATE_DISABLE |
+                       OVCUNIT_CLOCK_GATE_DISABLE;
+               if (IS_GM45(dev))
+                       dspclk_gate |= DSSUNIT_CLOCK_GATE_DISABLE;
+               I915_WRITE(DSPCLK_GATE_D, dspclk_gate);
+       } else if (IS_I965GM(dev)) {
+               I915_WRITE(RENCLK_GATE_D1, I965_RCC_CLOCK_GATE_DISABLE);
+               I915_WRITE(RENCLK_GATE_D2, 0);
+               I915_WRITE(DSPCLK_GATE_D, 0);
+               I915_WRITE(RAMCLK_GATE_D, 0);
+               I915_WRITE16(DEUC, 0);
+       } else if (IS_I965G(dev)) {
+               I915_WRITE(RENCLK_GATE_D1, I965_RCZ_CLOCK_GATE_DISABLE |
+                      I965_RCC_CLOCK_GATE_DISABLE |
+                      I965_RCPB_CLOCK_GATE_DISABLE |
+                      I965_ISC_CLOCK_GATE_DISABLE |
+                      I965_FBC_CLOCK_GATE_DISABLE);
+               I915_WRITE(RENCLK_GATE_D2, 0);
+       } else if (IS_I9XX(dev)) {
+               u32 dstate = I915_READ(D_STATE);
+
+               dstate |= DSTATE_PLL_D3_OFF | DSTATE_GFX_CLOCK_GATING |
+                       DSTATE_DOT_CLOCK_GATING;
+               I915_WRITE(D_STATE, dstate);
+       } else if (IS_I855(dev) || IS_I865G(dev)) {
+               I915_WRITE(RENCLK_GATE_D1, SV_CLOCK_GATE_DISABLE);
+       } else if (IS_I830(dev)) {
+               I915_WRITE(DSPCLK_GATE_D, OVRUNIT_CLOCK_GATE_DISABLE);
+       }
+}
+
 void intel_modeset_init(struct drm_device *dev)
 {
+       struct drm_i915_private *dev_priv = dev->dev_private;
        int num_pipe;
        int i;
 
        DRM_DEBUG("%d display pipe%s available.\n",
                  num_pipe, num_pipe > 1 ? "s" : "");
 
+       if (IS_I85X(dev))
+               pci_read_config_word(dev->pdev, HPLLCC, &dev_priv->orig_clock);
+       else if (IS_I9XX(dev) || IS_G4X(dev))
+               pci_read_config_word(dev->pdev, GCFGC, &dev_priv->orig_clock);
+
        for (i = 0; i < num_pipe; i++) {
                intel_crtc_init(dev, i);
        }
 
        intel_setup_outputs(dev);
+
+       intel_init_clock_gating(dev);
+
+       INIT_WORK(&dev_priv->idle_work, intel_idle_update);
+       setup_timer(&dev_priv->idle_timer, intel_gpu_idle_timer,
+                   (unsigned long)dev);
 }
 
 void intel_modeset_cleanup(struct drm_device *dev)
 {
+       struct drm_i915_private *dev_priv = dev->dev_private;
+       struct drm_crtc *crtc;
+       struct intel_crtc *intel_crtc;
+
+       mutex_lock(&dev->struct_mutex);
+
+       list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
+               /* Skip inactive CRTCs */
+               if (!crtc->fb)
+                       continue;
+
+               intel_crtc = to_intel_crtc(crtc);
+               intel_increase_pllclock(crtc, false);
+               del_timer_sync(&intel_crtc->idle_timer);
+       }
+
+       intel_increase_renderclock(dev, false);
+       del_timer_sync(&dev_priv->idle_timer);
+
+       mutex_unlock(&dev->struct_mutex);
+
        drm_mode_config_cleanup(dev);
 }