drm/i915: framebuffer compression for pre-GM45
This patch adds framebuffer compression (good for about ~0.5W power
savings in the best case) support for pre-GM45 chips. GM45+ have a new,
more flexible FBC scheme that will be added in a separate patch.
FBC can't always be enabled: the compressed buffer must be physically
contiguous and reside in stolen space. So if you have a large display
and a small amount of stolen memory, you may not be able to take
advantage of FBC. In some cases, a BIOS setting controls how much
stolen space is available. Increasing this to 8 or 16M can help.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 92e0aae..cadb9ef 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -954,6 +954,174 @@
mdelay(20);
}
+/* Parameters have changed, update FBC info */
+static void i8xx_enable_fbc(struct drm_crtc *crtc, unsigned long interval)
+{
+ struct drm_device *dev = crtc->dev;
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ struct drm_framebuffer *fb = crtc->fb;
+ struct intel_framebuffer *intel_fb = to_intel_framebuffer(fb);
+ struct drm_i915_gem_object *obj_priv = intel_fb->obj->driver_private;
+ struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
+ int plane, i;
+ u32 fbc_ctl, fbc_ctl2;
+
+ dev_priv->cfb_pitch = dev_priv->cfb_size / FBC_LL_SIZE;
+
+ if (fb->pitch < dev_priv->cfb_pitch)
+ dev_priv->cfb_pitch = fb->pitch;
+
+ /* FBC_CTL wants 64B units */
+ dev_priv->cfb_pitch = (dev_priv->cfb_pitch / 64) - 1;
+ dev_priv->cfb_fence = obj_priv->fence_reg;
+ dev_priv->cfb_plane = intel_crtc->plane;
+ plane = dev_priv->cfb_plane == 0 ? FBC_CTL_PLANEA : FBC_CTL_PLANEB;
+
+ /* Clear old tags */
+ for (i = 0; i < (FBC_LL_SIZE / 32) + 1; i++)
+ I915_WRITE(FBC_TAG + (i * 4), 0);
+
+ /* Set it up... */
+ fbc_ctl2 = FBC_CTL_FENCE_DBL | FBC_CTL_IDLE_IMM | plane;
+ if (obj_priv->tiling_mode != I915_TILING_NONE)
+ fbc_ctl2 |= FBC_CTL_CPU_FENCE;
+ I915_WRITE(FBC_CONTROL2, fbc_ctl2);
+ I915_WRITE(FBC_FENCE_OFF, crtc->y);
+
+ /* enable it... */
+ fbc_ctl = FBC_CTL_EN | FBC_CTL_PERIODIC;
+ fbc_ctl |= (dev_priv->cfb_pitch & 0xff) << FBC_CTL_STRIDE_SHIFT;
+ fbc_ctl |= (interval & 0x2fff) << FBC_CTL_INTERVAL_SHIFT;
+ if (obj_priv->tiling_mode != I915_TILING_NONE)
+ fbc_ctl |= dev_priv->cfb_fence;
+ I915_WRITE(FBC_CONTROL, fbc_ctl);
+
+ DRM_DEBUG("enabled FBC, pitch %ld, yoff %d, plane %d, ",
+ dev_priv->cfb_pitch, crtc->y, dev_priv->cfb_plane);
+}
+
+void i8xx_disable_fbc(struct drm_device *dev)
+{
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ u32 fbc_ctl;
+
+ /* Disable compression */
+ fbc_ctl = I915_READ(FBC_CONTROL);
+ fbc_ctl &= ~FBC_CTL_EN;
+ I915_WRITE(FBC_CONTROL, fbc_ctl);
+
+ /* Wait for compressing bit to clear */
+ while (I915_READ(FBC_STATUS) & FBC_STAT_COMPRESSING)
+ ; /* nothing */
+
+ intel_wait_for_vblank(dev);
+
+ DRM_DEBUG("disabled FBC\n");
+}
+
+static bool i8xx_fbc_enabled(struct drm_crtc *crtc)
+{
+ struct drm_device *dev = crtc->dev;
+ struct drm_i915_private *dev_priv = dev->dev_private;
+
+ return I915_READ(FBC_CONTROL) & FBC_CTL_EN;
+}
+
+/**
+ * intel_update_fbc - enable/disable FBC as needed
+ * @crtc: CRTC to point the compressor at
+ * @mode: mode in use
+ *
+ * Set up the framebuffer compression hardware at mode set time. We
+ * enable it if possible:
+ * - plane A only (on pre-965)
+ * - no pixel mulitply/line duplication
+ * - no alpha buffer discard
+ * - no dual wide
+ * - framebuffer <= 2048 in width, 1536 in height
+ *
+ * We can't assume that any compression will take place (worst case),
+ * so the compressed buffer has to be the same size as the uncompressed
+ * one. It also must reside (along with the line length buffer) in
+ * stolen memory.
+ *
+ * We need to enable/disable FBC on a global basis.
+ */
+static void intel_update_fbc(struct drm_crtc *crtc,
+ struct drm_display_mode *mode)
+{
+ struct drm_device *dev = crtc->dev;
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ struct drm_framebuffer *fb = crtc->fb;
+ struct intel_framebuffer *intel_fb;
+ struct drm_i915_gem_object *obj_priv;
+ struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
+ int plane = intel_crtc->plane;
+
+ if (!i915_powersave)
+ return;
+
+ if (!crtc->fb)
+ return;
+
+ intel_fb = to_intel_framebuffer(fb);
+ obj_priv = intel_fb->obj->driver_private;
+
+ /*
+ * If FBC is already on, we just have to verify that we can
+ * keep it that way...
+ * Need to disable if:
+ * - changing FBC params (stride, fence, mode)
+ * - new fb is too large to fit in compressed buffer
+ * - going to an unsupported config (interlace, pixel multiply, etc.)
+ */
+ if (intel_fb->obj->size > dev_priv->cfb_size) {
+ DRM_DEBUG("framebuffer too large, disabling compression\n");
+ goto out_disable;
+ }
+ if ((mode->flags & DRM_MODE_FLAG_INTERLACE) ||
+ (mode->flags & DRM_MODE_FLAG_DBLSCAN)) {
+ DRM_DEBUG("mode incompatible with compression, disabling\n");
+ goto out_disable;
+ }
+ if ((mode->hdisplay > 2048) ||
+ (mode->vdisplay > 1536)) {
+ DRM_DEBUG("mode too large for compression, disabling\n");
+ goto out_disable;
+ }
+ if (IS_I9XX(dev) && plane != 0) {
+ DRM_DEBUG("plane not 0, disabling compression\n");
+ goto out_disable;
+ }
+ if (obj_priv->tiling_mode != I915_TILING_X) {
+ DRM_DEBUG("framebuffer not tiled, disabling compression\n");
+ goto out_disable;
+ }
+
+ if (i8xx_fbc_enabled(crtc)) {
+ /* We can re-enable it in this case, but need to update pitch */
+ if (fb->pitch > dev_priv->cfb_pitch)
+ i8xx_disable_fbc(dev);
+ if (obj_priv->fence_reg != dev_priv->cfb_fence)
+ i8xx_disable_fbc(dev);
+ if (plane != dev_priv->cfb_plane)
+ i8xx_disable_fbc(dev);
+ }
+
+ if (!i8xx_fbc_enabled(crtc)) {
+ /* Now try to turn it back on if possible */
+ i8xx_enable_fbc(crtc, 500);
+ }
+
+ return;
+
+out_disable:
+ DRM_DEBUG("unsupported config, disabling FBC\n");
+ /* Multiple disables should be harmless */
+ if (i8xx_fbc_enabled(crtc))
+ i8xx_disable_fbc(dev);
+}
+
static int
intel_pipe_set_base(struct drm_crtc *crtc, int x, int y,
struct drm_framebuffer *old_fb)
@@ -966,12 +1134,13 @@
struct drm_i915_gem_object *obj_priv;
struct drm_gem_object *obj;
int pipe = intel_crtc->pipe;
+ int plane = intel_crtc->plane;
unsigned long Start, Offset;
- int dspbase = (pipe == 0 ? DSPAADDR : DSPBADDR);
- int dspsurf = (pipe == 0 ? DSPASURF : DSPBSURF);
- int dspstride = (pipe == 0) ? DSPASTRIDE : DSPBSTRIDE;
- int dsptileoff = (pipe == 0 ? DSPATILEOFF : DSPBTILEOFF);
- int dspcntr_reg = (pipe == 0) ? DSPACNTR : DSPBCNTR;
+ int dspbase = (plane == 0 ? DSPAADDR : DSPBADDR);
+ int dspsurf = (plane == 0 ? DSPASURF : DSPBSURF);
+ int dspstride = (plane == 0) ? DSPASTRIDE : DSPBSTRIDE;
+ int dsptileoff = (plane == 0 ? DSPATILEOFF : DSPBTILEOFF);
+ int dspcntr_reg = (plane == 0) ? DSPACNTR : DSPBCNTR;
u32 dspcntr, alignment;
int ret;
@@ -981,12 +1150,12 @@
return 0;
}
- switch (pipe) {
+ switch (plane) {
case 0:
case 1:
break;
default:
- DRM_ERROR("Can't update pipe %d in SAREA\n", pipe);
+ DRM_ERROR("Can't update plane %d in SAREA\n", plane);
return -EINVAL;
}
@@ -1114,6 +1283,9 @@
master_priv->sarea_priv->pipeA_y = y;
}
+ if (I915_HAS_FBC(dev) && (IS_I965G(dev) || plane == 0))
+ intel_update_fbc(crtc, &crtc->mode);
+
return 0;
}
@@ -1534,9 +1706,10 @@
struct drm_i915_private *dev_priv = dev->dev_private;
struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
int pipe = intel_crtc->pipe;
+ int plane = intel_crtc->plane;
int dpll_reg = (pipe == 0) ? DPLL_A : DPLL_B;
- int dspcntr_reg = (pipe == 0) ? DSPACNTR : DSPBCNTR;
- int dspbase_reg = (pipe == 0) ? DSPAADDR : DSPBADDR;
+ int dspcntr_reg = (plane == 0) ? DSPACNTR : DSPBCNTR;
+ int dspbase_reg = (plane == 0) ? DSPAADDR : DSPBADDR;
int pipeconf_reg = (pipe == 0) ? PIPEACONF : PIPEBCONF;
u32 temp;
@@ -1579,6 +1752,9 @@
intel_crtc_load_lut(crtc);
+ if (I915_HAS_FBC(dev) && (IS_I965G(dev) || plane == 0))
+ intel_update_fbc(crtc, &crtc->mode);
+
/* Give the overlay scaler a chance to enable if it's on this pipe */
//intel_crtc_dpms_video(crtc, true); TODO
intel_update_watermarks(dev);
@@ -1588,6 +1764,9 @@
/* Give the overlay scaler a chance to disable if it's on this pipe */
//intel_crtc_dpms_video(crtc, FALSE); TODO
+ if (dev_priv->cfb_plane == plane)
+ i8xx_disable_fbc(dev);
+
/* Disable the VGA plane that we never use */
i915_disable_vga(dev);
@@ -2325,10 +2504,11 @@
struct drm_i915_private *dev_priv = dev->dev_private;
struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
int pipe = intel_crtc->pipe;
+ int plane = intel_crtc->plane;
int fp_reg = (pipe == 0) ? FPA0 : FPB0;
int dpll_reg = (pipe == 0) ? DPLL_A : DPLL_B;
int dpll_md_reg = (intel_crtc->pipe == 0) ? DPLL_A_MD : DPLL_B_MD;
- int dspcntr_reg = (pipe == 0) ? DSPACNTR : DSPBCNTR;
+ int dspcntr_reg = (plane == 0) ? DSPACNTR : DSPBCNTR;
int pipeconf_reg = (pipe == 0) ? PIPEACONF : PIPEBCONF;
int htot_reg = (pipe == 0) ? HTOTAL_A : HTOTAL_B;
int hblank_reg = (pipe == 0) ? HBLANK_A : HBLANK_B;
@@ -2336,8 +2516,8 @@
int vtot_reg = (pipe == 0) ? VTOTAL_A : VTOTAL_B;
int vblank_reg = (pipe == 0) ? VBLANK_A : VBLANK_B;
int vsync_reg = (pipe == 0) ? VSYNC_A : VSYNC_B;
- int dspsize_reg = (pipe == 0) ? DSPASIZE : DSPBSIZE;
- int dsppos_reg = (pipe == 0) ? DSPAPOS : DSPBPOS;
+ int dspsize_reg = (plane == 0) ? DSPASIZE : DSPBSIZE;
+ int dsppos_reg = (plane == 0) ? DSPAPOS : DSPBPOS;
int pipesrc_reg = (pipe == 0) ? PIPEASRC : PIPEBSRC;
int refclk, num_outputs = 0;
intel_clock_t clock, reduced_clock;
@@ -2570,7 +2750,7 @@
enable color space conversion */
if (!IS_IGDNG(dev)) {
if (pipe == 0)
- dspcntr |= DISPPLANE_SEL_PIPE_A;
+ dspcntr &= ~DISPPLANE_SEL_PIPE_MASK;
else
dspcntr |= DISPPLANE_SEL_PIPE_B;
}
@@ -2739,6 +2919,8 @@
/* Flush the plane changes */
ret = intel_pipe_set_base(crtc, x, y, old_fb);
+ if (I915_HAS_FBC(dev) && (IS_I965G(dev) || plane == 0))
+ intel_update_fbc(crtc, &crtc->mode);
intel_update_watermarks(dev);
drm_vblank_post_modeset(dev, pipe);
@@ -2783,6 +2965,7 @@
struct drm_gem_object *bo;
struct drm_i915_gem_object *obj_priv;
int pipe = intel_crtc->pipe;
+ int plane = intel_crtc->plane;
uint32_t control = (pipe == 0) ? CURACNTR : CURBCNTR;
uint32_t base = (pipe == 0) ? CURABASE : CURBBASE;
uint32_t temp = I915_READ(control);
@@ -2868,6 +3051,10 @@
i915_gem_object_unpin(intel_crtc->cursor_bo);
drm_gem_object_unreference(intel_crtc->cursor_bo);
}
+
+ if (I915_HAS_FBC(dev) && (IS_I965G(dev) || plane == 0))
+ intel_update_fbc(crtc, &crtc->mode);
+
mutex_unlock(&dev->struct_mutex);
intel_crtc->cursor_addr = addr;
@@ -3549,6 +3736,14 @@
intel_crtc->lut_b[i] = i;
}
+ /* Swap pipes & planes for FBC on pre-965 */
+ intel_crtc->pipe = pipe;
+ intel_crtc->plane = pipe;
+ if (IS_MOBILE(dev) && (IS_I9XX(dev) && !IS_I965G(dev))) {
+ DRM_DEBUG("swapping pipes & planes for FBC\n");
+ intel_crtc->plane = ((pipe == 0) ? 1 : 0);
+ }
+
intel_crtc->cursor_addr = 0;
intel_crtc->dpms_mode = DRM_MODE_DPMS_OFF;
drm_crtc_helper_add(&intel_crtc->base, &intel_helper_funcs);
@@ -3909,6 +4104,7 @@
mutex_unlock(&dev->struct_mutex);
+ i8xx_disable_fbc(dev);
drm_mode_config_cleanup(dev);
}