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path: root/drivers/gpu/drm/i915/intel_fbc.c
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Diffstat (limited to 'drivers/gpu/drm/i915/intel_fbc.c')
-rw-r--r--drivers/gpu/drm/i915/intel_fbc.c1328
1 files changed, 1328 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/intel_fbc.c b/drivers/gpu/drm/i915/intel_fbc.c
new file mode 100644
index 000000000..728a20e1f
--- /dev/null
+++ b/drivers/gpu/drm/i915/intel_fbc.c
@@ -0,0 +1,1328 @@
+/*
+ * Copyright © 2014 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+/**
+ * DOC: Frame Buffer Compression (FBC)
+ *
+ * FBC tries to save memory bandwidth (and so power consumption) by
+ * compressing the amount of memory used by the display. It is total
+ * transparent to user space and completely handled in the kernel.
+ *
+ * The benefits of FBC are mostly visible with solid backgrounds and
+ * variation-less patterns. It comes from keeping the memory footprint small
+ * and having fewer memory pages opened and accessed for refreshing the display.
+ *
+ * i915 is responsible to reserve stolen memory for FBC and configure its
+ * offset on proper registers. The hardware takes care of all
+ * compress/decompress. However there are many known cases where we have to
+ * forcibly disable it to allow proper screen updates.
+ */
+
+#include "intel_drv.h"
+#include "i915_drv.h"
+
+static inline bool fbc_supported(struct drm_i915_private *dev_priv)
+{
+ return HAS_FBC(dev_priv);
+}
+
+static inline bool no_fbc_on_multiple_pipes(struct drm_i915_private *dev_priv)
+{
+ return INTEL_GEN(dev_priv) <= 3;
+}
+
+/*
+ * In some platforms where the CRTC's x:0/y:0 coordinates doesn't match the
+ * frontbuffer's x:0/y:0 coordinates we lie to the hardware about the plane's
+ * origin so the x and y offsets can actually fit the registers. As a
+ * consequence, the fence doesn't really start exactly at the display plane
+ * address we program because it starts at the real start of the buffer, so we
+ * have to take this into consideration here.
+ */
+static unsigned int get_crtc_fence_y_offset(struct intel_fbc *fbc)
+{
+ return fbc->state_cache.plane.y - fbc->state_cache.plane.adjusted_y;
+}
+
+/*
+ * For SKL+, the plane source size used by the hardware is based on the value we
+ * write to the PLANE_SIZE register. For BDW-, the hardware looks at the value
+ * we wrote to PIPESRC.
+ */
+static void intel_fbc_get_plane_source_size(struct intel_fbc_state_cache *cache,
+ int *width, int *height)
+{
+ if (width)
+ *width = cache->plane.src_w;
+ if (height)
+ *height = cache->plane.src_h;
+}
+
+static int intel_fbc_calculate_cfb_size(struct drm_i915_private *dev_priv,
+ struct intel_fbc_state_cache *cache)
+{
+ int lines;
+
+ intel_fbc_get_plane_source_size(cache, NULL, &lines);
+ if (INTEL_GEN(dev_priv) == 7)
+ lines = min(lines, 2048);
+ else if (INTEL_GEN(dev_priv) >= 8)
+ lines = min(lines, 2560);
+
+ /* Hardware needs the full buffer stride, not just the active area. */
+ return lines * cache->fb.stride;
+}
+
+static void i8xx_fbc_deactivate(struct drm_i915_private *dev_priv)
+{
+ u32 fbc_ctl;
+
+ /* Disable compression */
+ fbc_ctl = I915_READ(FBC_CONTROL);
+ if ((fbc_ctl & FBC_CTL_EN) == 0)
+ return;
+
+ fbc_ctl &= ~FBC_CTL_EN;
+ I915_WRITE(FBC_CONTROL, fbc_ctl);
+
+ /* Wait for compressing bit to clear */
+ if (intel_wait_for_register(dev_priv,
+ FBC_STATUS, FBC_STAT_COMPRESSING, 0,
+ 10)) {
+ DRM_DEBUG_KMS("FBC idle timed out\n");
+ return;
+ }
+}
+
+static void i8xx_fbc_activate(struct drm_i915_private *dev_priv)
+{
+ struct intel_fbc_reg_params *params = &dev_priv->fbc.params;
+ int cfb_pitch;
+ int i;
+ u32 fbc_ctl;
+
+ /* Note: fbc.threshold == 1 for i8xx */
+ cfb_pitch = params->cfb_size / FBC_LL_SIZE;
+ if (params->fb.stride < cfb_pitch)
+ cfb_pitch = params->fb.stride;
+
+ /* FBC_CTL wants 32B or 64B units */
+ if (IS_GEN2(dev_priv))
+ cfb_pitch = (cfb_pitch / 32) - 1;
+ else
+ cfb_pitch = (cfb_pitch / 64) - 1;
+
+ /* Clear old tags */
+ for (i = 0; i < (FBC_LL_SIZE / 32) + 1; i++)
+ I915_WRITE(FBC_TAG(i), 0);
+
+ if (IS_GEN4(dev_priv)) {
+ u32 fbc_ctl2;
+
+ /* Set it up... */
+ fbc_ctl2 = FBC_CTL_FENCE_DBL | FBC_CTL_IDLE_IMM | FBC_CTL_CPU_FENCE;
+ fbc_ctl2 |= FBC_CTL_PLANE(params->crtc.i9xx_plane);
+ I915_WRITE(FBC_CONTROL2, fbc_ctl2);
+ I915_WRITE(FBC_FENCE_OFF, params->crtc.fence_y_offset);
+ }
+
+ /* enable it... */
+ fbc_ctl = I915_READ(FBC_CONTROL);
+ fbc_ctl &= 0x3fff << FBC_CTL_INTERVAL_SHIFT;
+ fbc_ctl |= FBC_CTL_EN | FBC_CTL_PERIODIC;
+ if (IS_I945GM(dev_priv))
+ fbc_ctl |= FBC_CTL_C3_IDLE; /* 945 needs special SR handling */
+ fbc_ctl |= (cfb_pitch & 0xff) << FBC_CTL_STRIDE_SHIFT;
+ fbc_ctl |= params->vma->fence->id;
+ I915_WRITE(FBC_CONTROL, fbc_ctl);
+}
+
+static bool i8xx_fbc_is_active(struct drm_i915_private *dev_priv)
+{
+ return I915_READ(FBC_CONTROL) & FBC_CTL_EN;
+}
+
+static void g4x_fbc_activate(struct drm_i915_private *dev_priv)
+{
+ struct intel_fbc_reg_params *params = &dev_priv->fbc.params;
+ u32 dpfc_ctl;
+
+ dpfc_ctl = DPFC_CTL_PLANE(params->crtc.i9xx_plane) | DPFC_SR_EN;
+ if (params->fb.format->cpp[0] == 2)
+ dpfc_ctl |= DPFC_CTL_LIMIT_2X;
+ else
+ dpfc_ctl |= DPFC_CTL_LIMIT_1X;
+
+ if (params->flags & PLANE_HAS_FENCE) {
+ dpfc_ctl |= DPFC_CTL_FENCE_EN | params->vma->fence->id;
+ I915_WRITE(DPFC_FENCE_YOFF, params->crtc.fence_y_offset);
+ } else {
+ I915_WRITE(DPFC_FENCE_YOFF, 0);
+ }
+
+ /* enable it... */
+ I915_WRITE(DPFC_CONTROL, dpfc_ctl | DPFC_CTL_EN);
+}
+
+static void g4x_fbc_deactivate(struct drm_i915_private *dev_priv)
+{
+ u32 dpfc_ctl;
+
+ /* Disable compression */
+ dpfc_ctl = I915_READ(DPFC_CONTROL);
+ if (dpfc_ctl & DPFC_CTL_EN) {
+ dpfc_ctl &= ~DPFC_CTL_EN;
+ I915_WRITE(DPFC_CONTROL, dpfc_ctl);
+ }
+}
+
+static bool g4x_fbc_is_active(struct drm_i915_private *dev_priv)
+{
+ return I915_READ(DPFC_CONTROL) & DPFC_CTL_EN;
+}
+
+/* This function forces a CFB recompression through the nuke operation. */
+static void intel_fbc_recompress(struct drm_i915_private *dev_priv)
+{
+ I915_WRITE(MSG_FBC_REND_STATE, FBC_REND_NUKE);
+ POSTING_READ(MSG_FBC_REND_STATE);
+}
+
+static void ilk_fbc_activate(struct drm_i915_private *dev_priv)
+{
+ struct intel_fbc_reg_params *params = &dev_priv->fbc.params;
+ u32 dpfc_ctl;
+ int threshold = dev_priv->fbc.threshold;
+
+ dpfc_ctl = DPFC_CTL_PLANE(params->crtc.i9xx_plane);
+ if (params->fb.format->cpp[0] == 2)
+ threshold++;
+
+ switch (threshold) {
+ case 4:
+ case 3:
+ dpfc_ctl |= DPFC_CTL_LIMIT_4X;
+ break;
+ case 2:
+ dpfc_ctl |= DPFC_CTL_LIMIT_2X;
+ break;
+ case 1:
+ dpfc_ctl |= DPFC_CTL_LIMIT_1X;
+ break;
+ }
+
+ if (params->flags & PLANE_HAS_FENCE) {
+ dpfc_ctl |= DPFC_CTL_FENCE_EN;
+ if (IS_GEN5(dev_priv))
+ dpfc_ctl |= params->vma->fence->id;
+ if (IS_GEN6(dev_priv)) {
+ I915_WRITE(SNB_DPFC_CTL_SA,
+ SNB_CPU_FENCE_ENABLE |
+ params->vma->fence->id);
+ I915_WRITE(DPFC_CPU_FENCE_OFFSET,
+ params->crtc.fence_y_offset);
+ }
+ } else {
+ if (IS_GEN6(dev_priv)) {
+ I915_WRITE(SNB_DPFC_CTL_SA, 0);
+ I915_WRITE(DPFC_CPU_FENCE_OFFSET, 0);
+ }
+ }
+
+ I915_WRITE(ILK_DPFC_FENCE_YOFF, params->crtc.fence_y_offset);
+ I915_WRITE(ILK_FBC_RT_BASE,
+ i915_ggtt_offset(params->vma) | ILK_FBC_RT_VALID);
+ /* enable it... */
+ I915_WRITE(ILK_DPFC_CONTROL, dpfc_ctl | DPFC_CTL_EN);
+
+ intel_fbc_recompress(dev_priv);
+}
+
+static void ilk_fbc_deactivate(struct drm_i915_private *dev_priv)
+{
+ u32 dpfc_ctl;
+
+ /* Disable compression */
+ dpfc_ctl = I915_READ(ILK_DPFC_CONTROL);
+ if (dpfc_ctl & DPFC_CTL_EN) {
+ dpfc_ctl &= ~DPFC_CTL_EN;
+ I915_WRITE(ILK_DPFC_CONTROL, dpfc_ctl);
+ }
+}
+
+static bool ilk_fbc_is_active(struct drm_i915_private *dev_priv)
+{
+ return I915_READ(ILK_DPFC_CONTROL) & DPFC_CTL_EN;
+}
+
+static void gen7_fbc_activate(struct drm_i915_private *dev_priv)
+{
+ struct intel_fbc_reg_params *params = &dev_priv->fbc.params;
+ u32 dpfc_ctl;
+ int threshold = dev_priv->fbc.threshold;
+
+ /* Display WA #0529: skl, kbl, bxt. */
+ if (IS_GEN9(dev_priv) && !IS_GEMINILAKE(dev_priv)) {
+ u32 val = I915_READ(CHICKEN_MISC_4);
+
+ val &= ~(FBC_STRIDE_OVERRIDE | FBC_STRIDE_MASK);
+
+ if (i915_gem_object_get_tiling(params->vma->obj) !=
+ I915_TILING_X)
+ val |= FBC_STRIDE_OVERRIDE | params->gen9_wa_cfb_stride;
+
+ I915_WRITE(CHICKEN_MISC_4, val);
+ }
+
+ dpfc_ctl = 0;
+ if (IS_IVYBRIDGE(dev_priv))
+ dpfc_ctl |= IVB_DPFC_CTL_PLANE(params->crtc.i9xx_plane);
+
+ if (params->fb.format->cpp[0] == 2)
+ threshold++;
+
+ switch (threshold) {
+ case 4:
+ case 3:
+ dpfc_ctl |= DPFC_CTL_LIMIT_4X;
+ break;
+ case 2:
+ dpfc_ctl |= DPFC_CTL_LIMIT_2X;
+ break;
+ case 1:
+ dpfc_ctl |= DPFC_CTL_LIMIT_1X;
+ break;
+ }
+
+ if (params->flags & PLANE_HAS_FENCE) {
+ dpfc_ctl |= IVB_DPFC_CTL_FENCE_EN;
+ I915_WRITE(SNB_DPFC_CTL_SA,
+ SNB_CPU_FENCE_ENABLE |
+ params->vma->fence->id);
+ I915_WRITE(DPFC_CPU_FENCE_OFFSET, params->crtc.fence_y_offset);
+ } else {
+ I915_WRITE(SNB_DPFC_CTL_SA,0);
+ I915_WRITE(DPFC_CPU_FENCE_OFFSET, 0);
+ }
+
+ if (dev_priv->fbc.false_color)
+ dpfc_ctl |= FBC_CTL_FALSE_COLOR;
+
+ if (IS_IVYBRIDGE(dev_priv)) {
+ /* WaFbcAsynchFlipDisableFbcQueue:ivb */
+ I915_WRITE(ILK_DISPLAY_CHICKEN1,
+ I915_READ(ILK_DISPLAY_CHICKEN1) |
+ ILK_FBCQ_DIS);
+ } else if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv)) {
+ /* WaFbcAsynchFlipDisableFbcQueue:hsw,bdw */
+ I915_WRITE(CHICKEN_PIPESL_1(params->crtc.pipe),
+ I915_READ(CHICKEN_PIPESL_1(params->crtc.pipe)) |
+ HSW_FBCQ_DIS);
+ }
+
+ I915_WRITE(ILK_DPFC_CONTROL, dpfc_ctl | DPFC_CTL_EN);
+
+ intel_fbc_recompress(dev_priv);
+}
+
+static bool intel_fbc_hw_is_active(struct drm_i915_private *dev_priv)
+{
+ if (INTEL_GEN(dev_priv) >= 5)
+ return ilk_fbc_is_active(dev_priv);
+ else if (IS_GM45(dev_priv))
+ return g4x_fbc_is_active(dev_priv);
+ else
+ return i8xx_fbc_is_active(dev_priv);
+}
+
+static void intel_fbc_hw_activate(struct drm_i915_private *dev_priv)
+{
+ struct intel_fbc *fbc = &dev_priv->fbc;
+
+ fbc->active = true;
+
+ if (INTEL_GEN(dev_priv) >= 7)
+ gen7_fbc_activate(dev_priv);
+ else if (INTEL_GEN(dev_priv) >= 5)
+ ilk_fbc_activate(dev_priv);
+ else if (IS_GM45(dev_priv))
+ g4x_fbc_activate(dev_priv);
+ else
+ i8xx_fbc_activate(dev_priv);
+}
+
+static void intel_fbc_hw_deactivate(struct drm_i915_private *dev_priv)
+{
+ struct intel_fbc *fbc = &dev_priv->fbc;
+
+ fbc->active = false;
+
+ if (INTEL_GEN(dev_priv) >= 5)
+ ilk_fbc_deactivate(dev_priv);
+ else if (IS_GM45(dev_priv))
+ g4x_fbc_deactivate(dev_priv);
+ else
+ i8xx_fbc_deactivate(dev_priv);
+}
+
+/**
+ * intel_fbc_is_active - Is FBC active?
+ * @dev_priv: i915 device instance
+ *
+ * This function is used to verify the current state of FBC.
+ *
+ * FIXME: This should be tracked in the plane config eventually
+ * instead of queried at runtime for most callers.
+ */
+bool intel_fbc_is_active(struct drm_i915_private *dev_priv)
+{
+ return dev_priv->fbc.active;
+}
+
+static void intel_fbc_deactivate(struct drm_i915_private *dev_priv,
+ const char *reason)
+{
+ struct intel_fbc *fbc = &dev_priv->fbc;
+
+ WARN_ON(!mutex_is_locked(&fbc->lock));
+
+ if (fbc->active)
+ intel_fbc_hw_deactivate(dev_priv);
+
+ fbc->no_fbc_reason = reason;
+}
+
+static bool multiple_pipes_ok(struct intel_crtc *crtc,
+ struct intel_plane_state *plane_state)
+{
+ struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+ struct intel_fbc *fbc = &dev_priv->fbc;
+ enum pipe pipe = crtc->pipe;
+
+ /* Don't even bother tracking anything we don't need. */
+ if (!no_fbc_on_multiple_pipes(dev_priv))
+ return true;
+
+ if (plane_state->base.visible)
+ fbc->visible_pipes_mask |= (1 << pipe);
+ else
+ fbc->visible_pipes_mask &= ~(1 << pipe);
+
+ return (fbc->visible_pipes_mask & ~(1 << pipe)) != 0;
+}
+
+static int find_compression_threshold(struct drm_i915_private *dev_priv,
+ struct drm_mm_node *node,
+ int size,
+ int fb_cpp)
+{
+ int compression_threshold = 1;
+ int ret;
+ u64 end;
+
+ /* The FBC hardware for BDW/SKL doesn't have access to the stolen
+ * reserved range size, so it always assumes the maximum (8mb) is used.
+ * If we enable FBC using a CFB on that memory range we'll get FIFO
+ * underruns, even if that range is not reserved by the BIOS. */
+ if (IS_BROADWELL(dev_priv) || IS_GEN9_BC(dev_priv))
+ end = resource_size(&dev_priv->dsm) - 8 * 1024 * 1024;
+ else
+ end = U64_MAX;
+
+ /* HACK: This code depends on what we will do in *_enable_fbc. If that
+ * code changes, this code needs to change as well.
+ *
+ * The enable_fbc code will attempt to use one of our 2 compression
+ * thresholds, therefore, in that case, we only have 1 resort.
+ */
+
+ /* Try to over-allocate to reduce reallocations and fragmentation. */
+ ret = i915_gem_stolen_insert_node_in_range(dev_priv, node, size <<= 1,
+ 4096, 0, end);
+ if (ret == 0)
+ return compression_threshold;
+
+again:
+ /* HW's ability to limit the CFB is 1:4 */
+ if (compression_threshold > 4 ||
+ (fb_cpp == 2 && compression_threshold == 2))
+ return 0;
+
+ ret = i915_gem_stolen_insert_node_in_range(dev_priv, node, size >>= 1,
+ 4096, 0, end);
+ if (ret && INTEL_GEN(dev_priv) <= 4) {
+ return 0;
+ } else if (ret) {
+ compression_threshold <<= 1;
+ goto again;
+ } else {
+ return compression_threshold;
+ }
+}
+
+static int intel_fbc_alloc_cfb(struct intel_crtc *crtc)
+{
+ struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+ struct intel_fbc *fbc = &dev_priv->fbc;
+ struct drm_mm_node *uninitialized_var(compressed_llb);
+ int size, fb_cpp, ret;
+
+ WARN_ON(drm_mm_node_allocated(&fbc->compressed_fb));
+
+ size = intel_fbc_calculate_cfb_size(dev_priv, &fbc->state_cache);
+ fb_cpp = fbc->state_cache.fb.format->cpp[0];
+
+ ret = find_compression_threshold(dev_priv, &fbc->compressed_fb,
+ size, fb_cpp);
+ if (!ret)
+ goto err_llb;
+ else if (ret > 1) {
+ DRM_INFO("Reducing the compressed framebuffer size. This may lead to less power savings than a non-reduced-size. Try to increase stolen memory size if available in BIOS.\n");
+
+ }
+
+ fbc->threshold = ret;
+
+ if (INTEL_GEN(dev_priv) >= 5)
+ I915_WRITE(ILK_DPFC_CB_BASE, fbc->compressed_fb.start);
+ else if (IS_GM45(dev_priv)) {
+ I915_WRITE(DPFC_CB_BASE, fbc->compressed_fb.start);
+ } else {
+ compressed_llb = kzalloc(sizeof(*compressed_llb), GFP_KERNEL);
+ if (!compressed_llb)
+ goto err_fb;
+
+ ret = i915_gem_stolen_insert_node(dev_priv, compressed_llb,
+ 4096, 4096);
+ if (ret)
+ goto err_fb;
+
+ fbc->compressed_llb = compressed_llb;
+
+ GEM_BUG_ON(range_overflows_t(u64, dev_priv->dsm.start,
+ fbc->compressed_fb.start,
+ U32_MAX));
+ GEM_BUG_ON(range_overflows_t(u64, dev_priv->dsm.start,
+ fbc->compressed_llb->start,
+ U32_MAX));
+ I915_WRITE(FBC_CFB_BASE,
+ dev_priv->dsm.start + fbc->compressed_fb.start);
+ I915_WRITE(FBC_LL_BASE,
+ dev_priv->dsm.start + compressed_llb->start);
+ }
+
+ DRM_DEBUG_KMS("reserved %llu bytes of contiguous stolen space for FBC, threshold: %d\n",
+ fbc->compressed_fb.size, fbc->threshold);
+
+ return 0;
+
+err_fb:
+ kfree(compressed_llb);
+ i915_gem_stolen_remove_node(dev_priv, &fbc->compressed_fb);
+err_llb:
+ if (drm_mm_initialized(&dev_priv->mm.stolen))
+ pr_info_once("drm: not enough stolen space for compressed buffer (need %d more bytes), disabling. Hint: you may be able to increase stolen memory size in the BIOS to avoid this.\n", size);
+ return -ENOSPC;
+}
+
+static void __intel_fbc_cleanup_cfb(struct drm_i915_private *dev_priv)
+{
+ struct intel_fbc *fbc = &dev_priv->fbc;
+
+ if (drm_mm_node_allocated(&fbc->compressed_fb))
+ i915_gem_stolen_remove_node(dev_priv, &fbc->compressed_fb);
+
+ if (fbc->compressed_llb) {
+ i915_gem_stolen_remove_node(dev_priv, fbc->compressed_llb);
+ kfree(fbc->compressed_llb);
+ }
+}
+
+void intel_fbc_cleanup_cfb(struct drm_i915_private *dev_priv)
+{
+ struct intel_fbc *fbc = &dev_priv->fbc;
+
+ if (!fbc_supported(dev_priv))
+ return;
+
+ mutex_lock(&fbc->lock);
+ __intel_fbc_cleanup_cfb(dev_priv);
+ mutex_unlock(&fbc->lock);
+}
+
+static bool stride_is_valid(struct drm_i915_private *dev_priv,
+ unsigned int stride)
+{
+ /* This should have been caught earlier. */
+ if (WARN_ON_ONCE((stride & (64 - 1)) != 0))
+ return false;
+
+ /* Below are the additional FBC restrictions. */
+ if (stride < 512)
+ return false;
+
+ if (IS_GEN2(dev_priv) || IS_GEN3(dev_priv))
+ return stride == 4096 || stride == 8192;
+
+ if (IS_GEN4(dev_priv) && !IS_G4X(dev_priv) && stride < 2048)
+ return false;
+
+ if (stride > 16384)
+ return false;
+
+ return true;
+}
+
+static bool pixel_format_is_valid(struct drm_i915_private *dev_priv,
+ uint32_t pixel_format)
+{
+ switch (pixel_format) {
+ case DRM_FORMAT_XRGB8888:
+ case DRM_FORMAT_XBGR8888:
+ return true;
+ case DRM_FORMAT_XRGB1555:
+ case DRM_FORMAT_RGB565:
+ /* 16bpp not supported on gen2 */
+ if (IS_GEN2(dev_priv))
+ return false;
+ /* WaFbcOnly1to1Ratio:ctg */
+ if (IS_G4X(dev_priv))
+ return false;
+ return true;
+ default:
+ return false;
+ }
+}
+
+/*
+ * For some reason, the hardware tracking starts looking at whatever we
+ * programmed as the display plane base address register. It does not look at
+ * the X and Y offset registers. That's why we look at the crtc->adjusted{x,y}
+ * variables instead of just looking at the pipe/plane size.
+ */
+static bool intel_fbc_hw_tracking_covers_screen(struct intel_crtc *crtc)
+{
+ struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+ struct intel_fbc *fbc = &dev_priv->fbc;
+ unsigned int effective_w, effective_h, max_w, max_h;
+
+ if (INTEL_GEN(dev_priv) >= 8 || IS_HASWELL(dev_priv)) {
+ max_w = 4096;
+ max_h = 4096;
+ } else if (IS_G4X(dev_priv) || INTEL_GEN(dev_priv) >= 5) {
+ max_w = 4096;
+ max_h = 2048;
+ } else {
+ max_w = 2048;
+ max_h = 1536;
+ }
+
+ intel_fbc_get_plane_source_size(&fbc->state_cache, &effective_w,
+ &effective_h);
+ effective_w += fbc->state_cache.plane.adjusted_x;
+ effective_h += fbc->state_cache.plane.adjusted_y;
+
+ return effective_w <= max_w && effective_h <= max_h;
+}
+
+static void intel_fbc_update_state_cache(struct intel_crtc *crtc,
+ struct intel_crtc_state *crtc_state,
+ struct intel_plane_state *plane_state)
+{
+ struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+ struct intel_fbc *fbc = &dev_priv->fbc;
+ struct intel_fbc_state_cache *cache = &fbc->state_cache;
+ struct drm_framebuffer *fb = plane_state->base.fb;
+
+ cache->vma = NULL;
+ cache->flags = 0;
+
+ cache->crtc.mode_flags = crtc_state->base.adjusted_mode.flags;
+ if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv))
+ cache->crtc.hsw_bdw_pixel_rate = crtc_state->pixel_rate;
+
+ cache->plane.rotation = plane_state->base.rotation;
+ /*
+ * Src coordinates are already rotated by 270 degrees for
+ * the 90/270 degree plane rotation cases (to match the
+ * GTT mapping), hence no need to account for rotation here.
+ */
+ cache->plane.src_w = drm_rect_width(&plane_state->base.src) >> 16;
+ cache->plane.src_h = drm_rect_height(&plane_state->base.src) >> 16;
+ cache->plane.visible = plane_state->base.visible;
+ cache->plane.adjusted_x = plane_state->main.x;
+ cache->plane.adjusted_y = plane_state->main.y;
+ cache->plane.y = plane_state->base.src.y1 >> 16;
+
+ if (!cache->plane.visible)
+ return;
+
+ cache->fb.format = fb->format;
+ cache->fb.stride = fb->pitches[0];
+
+ cache->vma = plane_state->vma;
+ cache->flags = plane_state->flags;
+ if (WARN_ON(cache->flags & PLANE_HAS_FENCE && !cache->vma->fence))
+ cache->flags &= ~PLANE_HAS_FENCE;
+}
+
+static bool intel_fbc_can_activate(struct intel_crtc *crtc)
+{
+ struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+ struct intel_fbc *fbc = &dev_priv->fbc;
+ struct intel_fbc_state_cache *cache = &fbc->state_cache;
+
+ /* We don't need to use a state cache here since this information is
+ * global for all CRTC.
+ */
+ if (fbc->underrun_detected) {
+ fbc->no_fbc_reason = "underrun detected";
+ return false;
+ }
+
+ if (!cache->vma) {
+ fbc->no_fbc_reason = "primary plane not visible";
+ return false;
+ }
+
+ if (cache->crtc.mode_flags & DRM_MODE_FLAG_INTERLACE) {
+ fbc->no_fbc_reason = "incompatible mode";
+ return false;
+ }
+
+ if (!intel_fbc_hw_tracking_covers_screen(crtc)) {
+ fbc->no_fbc_reason = "mode too large for compression";
+ return false;
+ }
+
+ /* The use of a CPU fence is mandatory in order to detect writes
+ * by the CPU to the scanout and trigger updates to the FBC.
+ *
+ * Note that is possible for a tiled surface to be unmappable (and
+ * so have no fence associated with it) due to aperture constaints
+ * at the time of pinning.
+ *
+ * FIXME with 90/270 degree rotation we should use the fence on
+ * the normal GTT view (the rotated view doesn't even have a
+ * fence). Would need changes to the FBC fence Y offset as well.
+ * For now this will effecively disable FBC with 90/270 degree
+ * rotation.
+ */
+ if (!(cache->flags & PLANE_HAS_FENCE)) {
+ fbc->no_fbc_reason = "framebuffer not tiled or fenced";
+ return false;
+ }
+ if (INTEL_GEN(dev_priv) <= 4 && !IS_G4X(dev_priv) &&
+ cache->plane.rotation != DRM_MODE_ROTATE_0) {
+ fbc->no_fbc_reason = "rotation unsupported";
+ return false;
+ }
+
+ if (!stride_is_valid(dev_priv, cache->fb.stride)) {
+ fbc->no_fbc_reason = "framebuffer stride not supported";
+ return false;
+ }
+
+ if (!pixel_format_is_valid(dev_priv, cache->fb.format->format)) {
+ fbc->no_fbc_reason = "pixel format is invalid";
+ return false;
+ }
+
+ /* WaFbcExceedCdClockThreshold:hsw,bdw */
+ if ((IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv)) &&
+ cache->crtc.hsw_bdw_pixel_rate >= dev_priv->cdclk.hw.cdclk * 95 / 100) {
+ fbc->no_fbc_reason = "pixel rate is too big";
+ return false;
+ }
+
+ /* It is possible for the required CFB size change without a
+ * crtc->disable + crtc->enable since it is possible to change the
+ * stride without triggering a full modeset. Since we try to
+ * over-allocate the CFB, there's a chance we may keep FBC enabled even
+ * if this happens, but if we exceed the current CFB size we'll have to
+ * disable FBC. Notice that it would be possible to disable FBC, wait
+ * for a frame, free the stolen node, then try to reenable FBC in case
+ * we didn't get any invalidate/deactivate calls, but this would require
+ * a lot of tracking just for a specific case. If we conclude it's an
+ * important case, we can implement it later. */
+ if (intel_fbc_calculate_cfb_size(dev_priv, &fbc->state_cache) >
+ fbc->compressed_fb.size * fbc->threshold) {
+ fbc->no_fbc_reason = "CFB requirements changed";
+ return false;
+ }
+
+ /*
+ * Work around a problem on GEN9+ HW, where enabling FBC on a plane
+ * having a Y offset that isn't divisible by 4 causes FIFO underrun
+ * and screen flicker.
+ */
+ if (IS_GEN(dev_priv, 9, 10) &&
+ (fbc->state_cache.plane.adjusted_y & 3)) {
+ fbc->no_fbc_reason = "plane Y offset is misaligned";
+ return false;
+ }
+
+ return true;
+}
+
+static bool intel_fbc_can_enable(struct drm_i915_private *dev_priv)
+{
+ struct intel_fbc *fbc = &dev_priv->fbc;
+
+ if (intel_vgpu_active(dev_priv)) {
+ fbc->no_fbc_reason = "VGPU is active";
+ return false;
+ }
+
+ if (!i915_modparams.enable_fbc) {
+ fbc->no_fbc_reason = "disabled per module param or by default";
+ return false;
+ }
+
+ if (fbc->underrun_detected) {
+ fbc->no_fbc_reason = "underrun detected";
+ return false;
+ }
+
+ return true;
+}
+
+static void intel_fbc_get_reg_params(struct intel_crtc *crtc,
+ struct intel_fbc_reg_params *params)
+{
+ struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+ struct intel_fbc *fbc = &dev_priv->fbc;
+ struct intel_fbc_state_cache *cache = &fbc->state_cache;
+
+ /* Since all our fields are integer types, use memset here so the
+ * comparison function can rely on memcmp because the padding will be
+ * zero. */
+ memset(params, 0, sizeof(*params));
+
+ params->vma = cache->vma;
+ params->flags = cache->flags;
+
+ params->crtc.pipe = crtc->pipe;
+ params->crtc.i9xx_plane = to_intel_plane(crtc->base.primary)->i9xx_plane;
+ params->crtc.fence_y_offset = get_crtc_fence_y_offset(fbc);
+
+ params->fb.format = cache->fb.format;
+ params->fb.stride = cache->fb.stride;
+
+ params->cfb_size = intel_fbc_calculate_cfb_size(dev_priv, cache);
+
+ if (IS_GEN9(dev_priv) && !IS_GEMINILAKE(dev_priv))
+ params->gen9_wa_cfb_stride = DIV_ROUND_UP(cache->plane.src_w,
+ 32 * fbc->threshold) * 8;
+}
+
+void intel_fbc_pre_update(struct intel_crtc *crtc,
+ struct intel_crtc_state *crtc_state,
+ struct intel_plane_state *plane_state)
+{
+ struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+ struct intel_fbc *fbc = &dev_priv->fbc;
+ const char *reason = "update pending";
+
+ if (!fbc_supported(dev_priv))
+ return;
+
+ mutex_lock(&fbc->lock);
+
+ if (!multiple_pipes_ok(crtc, plane_state)) {
+ reason = "more than one pipe active";
+ goto deactivate;
+ }
+
+ if (!fbc->enabled || fbc->crtc != crtc)
+ goto unlock;
+
+ intel_fbc_update_state_cache(crtc, crtc_state, plane_state);
+ fbc->flip_pending = true;
+
+deactivate:
+ intel_fbc_deactivate(dev_priv, reason);
+unlock:
+ mutex_unlock(&fbc->lock);
+}
+
+/**
+ * __intel_fbc_disable - disable FBC
+ * @dev_priv: i915 device instance
+ *
+ * This is the low level function that actually disables FBC. Callers should
+ * grab the FBC lock.
+ */
+static void __intel_fbc_disable(struct drm_i915_private *dev_priv)
+{
+ struct intel_fbc *fbc = &dev_priv->fbc;
+ struct intel_crtc *crtc = fbc->crtc;
+
+ WARN_ON(!mutex_is_locked(&fbc->lock));
+ WARN_ON(!fbc->enabled);
+ WARN_ON(fbc->active);
+
+ DRM_DEBUG_KMS("Disabling FBC on pipe %c\n", pipe_name(crtc->pipe));
+
+ __intel_fbc_cleanup_cfb(dev_priv);
+
+ fbc->enabled = false;
+ fbc->crtc = NULL;
+}
+
+static void __intel_fbc_post_update(struct intel_crtc *crtc)
+{
+ struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+ struct intel_fbc *fbc = &dev_priv->fbc;
+
+ WARN_ON(!mutex_is_locked(&fbc->lock));
+
+ if (!fbc->enabled || fbc->crtc != crtc)
+ return;
+
+ fbc->flip_pending = false;
+ WARN_ON(fbc->active);
+
+ if (!i915_modparams.enable_fbc) {
+ intel_fbc_deactivate(dev_priv, "disabled at runtime per module param");
+ __intel_fbc_disable(dev_priv);
+
+ return;
+ }
+
+ intel_fbc_get_reg_params(crtc, &fbc->params);
+
+ if (!intel_fbc_can_activate(crtc))
+ return;
+
+ if (!fbc->busy_bits) {
+ intel_fbc_deactivate(dev_priv, "FBC enabled (active or scheduled)");
+ intel_fbc_hw_activate(dev_priv);
+ } else
+ intel_fbc_deactivate(dev_priv, "frontbuffer write");
+}
+
+void intel_fbc_post_update(struct intel_crtc *crtc)
+{
+ struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+ struct intel_fbc *fbc = &dev_priv->fbc;
+
+ if (!fbc_supported(dev_priv))
+ return;
+
+ mutex_lock(&fbc->lock);
+ __intel_fbc_post_update(crtc);
+ mutex_unlock(&fbc->lock);
+}
+
+static unsigned int intel_fbc_get_frontbuffer_bit(struct intel_fbc *fbc)
+{
+ if (fbc->enabled)
+ return to_intel_plane(fbc->crtc->base.primary)->frontbuffer_bit;
+ else
+ return fbc->possible_framebuffer_bits;
+}
+
+void intel_fbc_invalidate(struct drm_i915_private *dev_priv,
+ unsigned int frontbuffer_bits,
+ enum fb_op_origin origin)
+{
+ struct intel_fbc *fbc = &dev_priv->fbc;
+
+ if (!fbc_supported(dev_priv))
+ return;
+
+ if (origin == ORIGIN_GTT || origin == ORIGIN_FLIP)
+ return;
+
+ mutex_lock(&fbc->lock);
+
+ fbc->busy_bits |= intel_fbc_get_frontbuffer_bit(fbc) & frontbuffer_bits;
+
+ if (fbc->enabled && fbc->busy_bits)
+ intel_fbc_deactivate(dev_priv, "frontbuffer write");
+
+ mutex_unlock(&fbc->lock);
+}
+
+void intel_fbc_flush(struct drm_i915_private *dev_priv,
+ unsigned int frontbuffer_bits, enum fb_op_origin origin)
+{
+ struct intel_fbc *fbc = &dev_priv->fbc;
+
+ if (!fbc_supported(dev_priv))
+ return;
+
+ mutex_lock(&fbc->lock);
+
+ fbc->busy_bits &= ~frontbuffer_bits;
+
+ if (origin == ORIGIN_GTT || origin == ORIGIN_FLIP)
+ goto out;
+
+ if (!fbc->busy_bits && fbc->enabled &&
+ (frontbuffer_bits & intel_fbc_get_frontbuffer_bit(fbc))) {
+ if (fbc->active)
+ intel_fbc_recompress(dev_priv);
+ else if (!fbc->flip_pending)
+ __intel_fbc_post_update(fbc->crtc);
+ }
+
+out:
+ mutex_unlock(&fbc->lock);
+}
+
+/**
+ * intel_fbc_choose_crtc - select a CRTC to enable FBC on
+ * @dev_priv: i915 device instance
+ * @state: the atomic state structure
+ *
+ * This function looks at the proposed state for CRTCs and planes, then chooses
+ * which pipe is going to have FBC by setting intel_crtc_state->enable_fbc to
+ * true.
+ *
+ * Later, intel_fbc_enable is going to look for state->enable_fbc and then maybe
+ * enable FBC for the chosen CRTC. If it does, it will set dev_priv->fbc.crtc.
+ */
+void intel_fbc_choose_crtc(struct drm_i915_private *dev_priv,
+ struct intel_atomic_state *state)
+{
+ struct intel_fbc *fbc = &dev_priv->fbc;
+ struct intel_plane *plane;
+ struct intel_plane_state *plane_state;
+ bool crtc_chosen = false;
+ int i;
+
+ mutex_lock(&fbc->lock);
+
+ /* Does this atomic commit involve the CRTC currently tied to FBC? */
+ if (fbc->crtc &&
+ !intel_atomic_get_new_crtc_state(state, fbc->crtc))
+ goto out;
+
+ if (!intel_fbc_can_enable(dev_priv))
+ goto out;
+
+ /* Simply choose the first CRTC that is compatible and has a visible
+ * plane. We could go for fancier schemes such as checking the plane
+ * size, but this would just affect the few platforms that don't tie FBC
+ * to pipe or plane A. */
+ for_each_new_intel_plane_in_state(state, plane, plane_state, i) {
+ struct intel_crtc_state *crtc_state;
+ struct intel_crtc *crtc = to_intel_crtc(plane_state->base.crtc);
+
+ if (!plane->has_fbc)
+ continue;
+
+ if (!plane_state->base.visible)
+ continue;
+
+ crtc_state = intel_atomic_get_new_crtc_state(state, crtc);
+
+ crtc_state->enable_fbc = true;
+ crtc_chosen = true;
+ break;
+ }
+
+ if (!crtc_chosen)
+ fbc->no_fbc_reason = "no suitable CRTC for FBC";
+
+out:
+ mutex_unlock(&fbc->lock);
+}
+
+/**
+ * intel_fbc_enable: tries to enable FBC on the CRTC
+ * @crtc: the CRTC
+ * @crtc_state: corresponding &drm_crtc_state for @crtc
+ * @plane_state: corresponding &drm_plane_state for the primary plane of @crtc
+ *
+ * This function checks if the given CRTC was chosen for FBC, then enables it if
+ * possible. Notice that it doesn't activate FBC. It is valid to call
+ * intel_fbc_enable multiple times for the same pipe without an
+ * intel_fbc_disable in the middle, as long as it is deactivated.
+ */
+void intel_fbc_enable(struct intel_crtc *crtc,
+ struct intel_crtc_state *crtc_state,
+ struct intel_plane_state *plane_state)
+{
+ struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+ struct intel_fbc *fbc = &dev_priv->fbc;
+
+ if (!fbc_supported(dev_priv))
+ return;
+
+ mutex_lock(&fbc->lock);
+
+ if (fbc->enabled) {
+ WARN_ON(fbc->crtc == NULL);
+ if (fbc->crtc == crtc) {
+ WARN_ON(!crtc_state->enable_fbc);
+ WARN_ON(fbc->active);
+ }
+ goto out;
+ }
+
+ if (!crtc_state->enable_fbc)
+ goto out;
+
+ WARN_ON(fbc->active);
+ WARN_ON(fbc->crtc != NULL);
+
+ intel_fbc_update_state_cache(crtc, crtc_state, plane_state);
+ if (intel_fbc_alloc_cfb(crtc)) {
+ fbc->no_fbc_reason = "not enough stolen memory";
+ goto out;
+ }
+
+ DRM_DEBUG_KMS("Enabling FBC on pipe %c\n", pipe_name(crtc->pipe));
+ fbc->no_fbc_reason = "FBC enabled but not active yet\n";
+
+ fbc->enabled = true;
+ fbc->crtc = crtc;
+out:
+ mutex_unlock(&fbc->lock);
+}
+
+/**
+ * intel_fbc_disable - disable FBC if it's associated with crtc
+ * @crtc: the CRTC
+ *
+ * This function disables FBC if it's associated with the provided CRTC.
+ */
+void intel_fbc_disable(struct intel_crtc *crtc)
+{
+ struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+ struct intel_fbc *fbc = &dev_priv->fbc;
+
+ if (!fbc_supported(dev_priv))
+ return;
+
+ WARN_ON(crtc->active);
+
+ mutex_lock(&fbc->lock);
+ if (fbc->crtc == crtc)
+ __intel_fbc_disable(dev_priv);
+ mutex_unlock(&fbc->lock);
+}
+
+/**
+ * intel_fbc_global_disable - globally disable FBC
+ * @dev_priv: i915 device instance
+ *
+ * This function disables FBC regardless of which CRTC is associated with it.
+ */
+void intel_fbc_global_disable(struct drm_i915_private *dev_priv)
+{
+ struct intel_fbc *fbc = &dev_priv->fbc;
+
+ if (!fbc_supported(dev_priv))
+ return;
+
+ mutex_lock(&fbc->lock);
+ if (fbc->enabled) {
+ WARN_ON(fbc->crtc->active);
+ __intel_fbc_disable(dev_priv);
+ }
+ mutex_unlock(&fbc->lock);
+}
+
+static void intel_fbc_underrun_work_fn(struct work_struct *work)
+{
+ struct drm_i915_private *dev_priv =
+ container_of(work, struct drm_i915_private, fbc.underrun_work);
+ struct intel_fbc *fbc = &dev_priv->fbc;
+
+ mutex_lock(&fbc->lock);
+
+ /* Maybe we were scheduled twice. */
+ if (fbc->underrun_detected || !fbc->enabled)
+ goto out;
+
+ DRM_DEBUG_KMS("Disabling FBC due to FIFO underrun.\n");
+ fbc->underrun_detected = true;
+
+ intel_fbc_deactivate(dev_priv, "FIFO underrun");
+out:
+ mutex_unlock(&fbc->lock);
+}
+
+/*
+ * intel_fbc_reset_underrun - reset FBC fifo underrun status.
+ * @dev_priv: i915 device instance
+ *
+ * See intel_fbc_handle_fifo_underrun_irq(). For automated testing we
+ * want to re-enable FBC after an underrun to increase test coverage.
+ */
+int intel_fbc_reset_underrun(struct drm_i915_private *dev_priv)
+{
+ int ret;
+
+ cancel_work_sync(&dev_priv->fbc.underrun_work);
+
+ ret = mutex_lock_interruptible(&dev_priv->fbc.lock);
+ if (ret)
+ return ret;
+
+ if (dev_priv->fbc.underrun_detected) {
+ DRM_DEBUG_KMS("Re-allowing FBC after fifo underrun\n");
+ dev_priv->fbc.no_fbc_reason = "FIFO underrun cleared";
+ }
+
+ dev_priv->fbc.underrun_detected = false;
+ mutex_unlock(&dev_priv->fbc.lock);
+
+ return 0;
+}
+
+/**
+ * intel_fbc_handle_fifo_underrun_irq - disable FBC when we get a FIFO underrun
+ * @dev_priv: i915 device instance
+ *
+ * Without FBC, most underruns are harmless and don't really cause too many
+ * problems, except for an annoying message on dmesg. With FBC, underruns can
+ * become black screens or even worse, especially when paired with bad
+ * watermarks. So in order for us to be on the safe side, completely disable FBC
+ * in case we ever detect a FIFO underrun on any pipe. An underrun on any pipe
+ * already suggests that watermarks may be bad, so try to be as safe as
+ * possible.
+ *
+ * This function is called from the IRQ handler.
+ */
+void intel_fbc_handle_fifo_underrun_irq(struct drm_i915_private *dev_priv)
+{
+ struct intel_fbc *fbc = &dev_priv->fbc;
+
+ if (!fbc_supported(dev_priv))
+ return;
+
+ /* There's no guarantee that underrun_detected won't be set to true
+ * right after this check and before the work is scheduled, but that's
+ * not a problem since we'll check it again under the work function
+ * while FBC is locked. This check here is just to prevent us from
+ * unnecessarily scheduling the work, and it relies on the fact that we
+ * never switch underrun_detect back to false after it's true. */
+ if (READ_ONCE(fbc->underrun_detected))
+ return;
+
+ schedule_work(&fbc->underrun_work);
+}
+
+/**
+ * intel_fbc_init_pipe_state - initialize FBC's CRTC visibility tracking
+ * @dev_priv: i915 device instance
+ *
+ * The FBC code needs to track CRTC visibility since the older platforms can't
+ * have FBC enabled while multiple pipes are used. This function does the
+ * initial setup at driver load to make sure FBC is matching the real hardware.
+ */
+void intel_fbc_init_pipe_state(struct drm_i915_private *dev_priv)
+{
+ struct intel_crtc *crtc;
+
+ /* Don't even bother tracking anything if we don't need. */
+ if (!no_fbc_on_multiple_pipes(dev_priv))
+ return;
+
+ for_each_intel_crtc(&dev_priv->drm, crtc)
+ if (intel_crtc_active(crtc) &&
+ crtc->base.primary->state->visible)
+ dev_priv->fbc.visible_pipes_mask |= (1 << crtc->pipe);
+}
+
+/*
+ * The DDX driver changes its behavior depending on the value it reads from
+ * i915.enable_fbc, so sanitize it by translating the default value into either
+ * 0 or 1 in order to allow it to know what's going on.
+ *
+ * Notice that this is done at driver initialization and we still allow user
+ * space to change the value during runtime without sanitizing it again. IGT
+ * relies on being able to change i915.enable_fbc at runtime.
+ */
+static int intel_sanitize_fbc_option(struct drm_i915_private *dev_priv)
+{
+ if (i915_modparams.enable_fbc >= 0)
+ return !!i915_modparams.enable_fbc;
+
+ if (!HAS_FBC(dev_priv))
+ return 0;
+
+ /* https://bugs.freedesktop.org/show_bug.cgi?id=108085 */
+ if (IS_GEMINILAKE(dev_priv))
+ return 0;
+
+ if (IS_BROADWELL(dev_priv) || INTEL_GEN(dev_priv) >= 9)
+ return 1;
+
+ return 0;
+}
+
+static bool need_fbc_vtd_wa(struct drm_i915_private *dev_priv)
+{
+ /* WaFbcTurnOffFbcWhenHyperVisorIsUsed:skl,bxt */
+ if (intel_vtd_active() &&
+ (IS_SKYLAKE(dev_priv) || IS_BROXTON(dev_priv))) {
+ DRM_INFO("Disabling framebuffer compression (FBC) to prevent screen flicker with VT-d enabled\n");
+ return true;
+ }
+
+ return false;
+}
+
+/**
+ * intel_fbc_init - Initialize FBC
+ * @dev_priv: the i915 device
+ *
+ * This function might be called during PM init process.
+ */
+void intel_fbc_init(struct drm_i915_private *dev_priv)
+{
+ struct intel_fbc *fbc = &dev_priv->fbc;
+
+ INIT_WORK(&fbc->underrun_work, intel_fbc_underrun_work_fn);
+ mutex_init(&fbc->lock);
+ fbc->enabled = false;
+ fbc->active = false;
+
+ if (need_fbc_vtd_wa(dev_priv))
+ mkwrite_device_info(dev_priv)->has_fbc = false;
+
+ i915_modparams.enable_fbc = intel_sanitize_fbc_option(dev_priv);
+ DRM_DEBUG_KMS("Sanitized enable_fbc value: %d\n",
+ i915_modparams.enable_fbc);
+
+ if (!HAS_FBC(dev_priv)) {
+ fbc->no_fbc_reason = "unsupported by this chipset";
+ return;
+ }
+
+ /* This value was pulled out of someone's hat */
+ if (INTEL_GEN(dev_priv) <= 4 && !IS_GM45(dev_priv))
+ I915_WRITE(FBC_CONTROL, 500 << FBC_CTL_INTERVAL_SHIFT);
+
+ /* We still don't have any sort of hardware state readout for FBC, so
+ * deactivate it in case the BIOS activated it to make sure software
+ * matches the hardware state. */
+ if (intel_fbc_hw_is_active(dev_priv))
+ intel_fbc_hw_deactivate(dev_priv);
+}